MINISTRY OF EDUCATION MINISTRY OF

AND TRAINING NATIONAL DEFENCE

VIETNAM MILITARY MEDICAL UNIVERSITY

TRINH VAN THONG

STUDY THE ROLE OF BONE SCINTIGRAPHY  AND EVALUATE THE RESULTS  OF TREATMENT OF OSTEOSARCOMA

Specialty: Surgery

Code:  9720104

PH.D. THESIS SUMMARY

HANOI ­ 2019

THE RESEARCH WAS FINISHED AT VIETNAM MILITARY MEDICAL UNIVERSITY

Supervisors:

1. Assoc.Prof. Ph.D. Tran Dinh Chien 2. Assoc.Prof. Ph.D. Nguyen Dai Binh

Judge 1: Assoc.Prof. Ph.D. Tran Trung Dung

Judge 2: Assoc.Prof. Ph.D. Le Ngoc Ha

Judge 3: Assoc.Prof. Ph.D. Nguyen Manh Khanh

The thesis will be defended before the Thesis Assessment Council at

Institute level

At: Vietnam military medical university

Date        month        year

The thesis can be found at: ­ National library

­ Vietnam military medical university library

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INTRODUCTION

1. Regarding the current situation, necessity, scientific and practical

significance of the dissertation topic

Osteosarcoma   is   the   most   common   primary   bone   cancer   and

accounts  for about 35%  of  all primary bone cancers. In the years

before 1980, the only treatment was amputation and even with early

surgery, the overall survival rate after 5 years was not more than 20%

and the main cause of death is due to lung metastasis.

From the 1980s onwards, the combination of chemotherapy  and

then surgery has significantly improved the survival rate for patients.

When chemotherapy is combined, the problem is how to assess the

level   of   histomorphological   response   to   the   drug.   Evaluation

measures   through   tissue   necrosis   have   many   limitations   due   to

surgical intervention and depending on method of taking samples,

reading test results…

Bone   scintigraphy   allows   assessment   of   preoperative

chemotherapy   respond   through   TBR   index   changes   in   the   tumor,

allows detection of recurrence of local lesions and more complete

distant   metastasis   than   other   diagnostic   imaging   methods   such   as

conventional X­rays, CT scans and MRI. Whereby, chemotherapy is

indicated,   especially   supplementation   of   treatment   when   relapsing

and metastasis is performed timely and effectively.

The dissertation topic: “Study the role of bone scintigraphy and

evaluate   the   results   of   treatment   of   osteosarcoma”   with   following

research objectives:

(1) Studying the role of bone scintigraphy in stage diagnosis and

the process of monitoring osteosarcoma treatment.

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(2)   Evaluating   the   effects   of   osteosarcoma   treatment   at   K

hospital in Ha Noi.

2.New contributions

The dissertation is the result of bone scintigraphy research at 4

times, assessing the role of bone scintigraphy in the stage diagnosis

through the early detection of micrometastases. The appropriateness

between changing AR  index before  and after  chemotherapy  in  57

patients with biopsy results assessing the degree of tumors necrosis

has shown that bone scintigraphy can be used to evaluation the tumor

response to  chemotherapy in osteosarcoma patients instead of tumor

conventional   biopsy   methods   applied   previously.   The   results   also

showed that bone scintigraphy is very valuable in monitoring early

detection of relapse and distant metastasis.

The thesis shows results of treatment, survival rate, survival

rate,   disease­free   survival   rate,   function   of   preserved   limbs,   and

factors   affecting   survival   rate.   This   is   a   valuable   reference   for

osteosarcoma treatment.

3. The dissertation structure

The dissertation consists of 129 pages, including: Introduction (2

pages),   Overview   (33   pages),   Subjects   and   method   (18   pages),

Results (29 pages), Discussions (47 pages), Conclusions (2 pages).

References   have   118   documents   including   14   Vietnamese

documents,   104   English   documents.   The   number   of   documents

published from 2009 onwards has 47/118 accounting for 39,8% (4

Vietnamese and 43 English).

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CHAPTER 1: OVERVIEW

1.1. Bone scintigraphy in diagnosis of osteosarcoma

Bone  scintigraphy  has a very high sensitivity, giving a general

picture of the whole bone system, helping to detect bone lesion if

any.   The   presence   of   one   or   more   regions   increasing   uptake   of

radionuclide   called   "hot   zones".   Such   lesions   may   include

osteomyelitis,   a   recent   fracture,   benign   bone   tumors   or   malignant

lesions.   For   differential   diagnosis   of   benign   or   malignant   bone

lesions,   Otto   Sneppen   conducted   simultaneously   anatomical

investigation and bone scintigraphy in patients with different lesions.

With   bone  scintigraphy,   the   author   measured   count   values  at   the

lesion area compared to the opposite bone area in the body (TBR).

After   comparing   the   result,   the   author   found   high   TBR   index   in

patients   with   malignant   lesions   and   lower   in   benign   lesions.

According   to   the   author,   the   threshold   of   TBR   index:   1.5   is

considered as the threshold that distinguishes benign and malignant

lesions on bone scintigraphy.

The presence of secondary lesion (metastasis) of bone changes

the stage of the tumor to stage III (Enniking) from any stage and

therefore,   the   treatment   strategy   also   changes.   In   osteosarcoma,

micrometastasis is present in about 20% of patients before starting

treatment.   This   explains   why   prior   to   the   development   of

chemotherapy, although the decision of amputations was extensive

for cases of osteosarcoma, the rate of early relapse after treatment

was also high.

Bone   scintigraphy,   in   addition   to   the   role   of   primary   tumor

monitoring   through   stages   in   which   the   patient   is   at   risk   of

developing  bone  metastases,   is   also  used  to  detect   possible  tumor

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mass after chemotherapy. The change in radiation uptake (reduction

or   disappearance)   after   treatment   shows   tumor   cell   necrosis.   The

changes TBR index before and after treatment shows the grade of

respond to treatment.

1.2. Histopathological Diagnosis

The   histopathological   results   are   the   criteria   in   diagnosing

osteosarcoma. Biopsy play an important role to accurately diagnose

of tumor malignancy before treatment.

In   osteosarcoma,   the   Hematocylin   Eosine   (HE)   stain   results

mainly   determine   whether   the   tumor   composition   can   have   three

forms: osteoblast cells, osteoclast cells and fibrous­forming cells.

In most cases, just relying on histopathology examination helps to

make   the   diagnosis   be   accurate.   However,   some   cases   of

histopathology   have   not   been   clearly   distinguished.   Immuno­

histochemistry   is   used   to   distinguish   the   primary   bone   cancer.

Immunohistochemistry   analysis   proves   tissue   origin   and   is   an

absolute reliable method.

1.3. Diagnose the osteosarcoma stage

Enneking stage system with bone sarcoma

Metastasis Stage Malignancy (G) Primary tumor (T) (M)

IA Low malignancy (G1) Inside cavity (T1) M0

IB Low malignancy (G1) Outside cavity (T2) M0

IIA High malignancy (G2) Inside cavity (T1) M0

IIB High malignancy (G2) Outside cavity (T2) M0

III Gx Tx M1

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CHAPTER 2: SUBJECTS AND METHODS

2.1 Subjects

Research is performed on 70 patients with osteosarcoma who are

treated in Hanoi K Hospital from January 2008 to June 2014.

2.1.1. Patient’s selection criteria

The patient selected must meet the following criteria:

­ Histopathological diagnosis are osteosarcoma.

­   Get   bone   scintigraphy   according   to   the   process:   Before   and

after  the   patient   has   3   cycles   of   preoperative   chemotherapy,   after

discharge and after leaving hospital for 3­6 months.

­ The tumors were located in the upper and lower limbs.

­ Surgical treatment combined chemotherapy with EOI regimen.

­ Patients agreed to participate in research.

2.1.2. Exclusion criteria

­ The patient had pulmonary metastases before treatment.

­ Patients with accompanying kidney and heart diseases.

­ Patients only treat surgery or chemicals alone.

­ Treatment combined with other regimens from the beginning.

­ Do not follow the full course of treatment.

2.2. Methods

Non­control prospective   clinical study, cross­sectional

description with follow­up monitoring.

2.2.1. Histopathological diagnosis

Locate   tumor   on   the   limbs   based   on   clinical   symptoms,

radiograph images, CT scans.

Biopsy samples taken in areas of the tumor do not have necrosis

or bleeding. The minimum size of biopsy sample is 1cm.

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Biopsy will be stained by HE and the results will be read by a

doctor   in   Department   of   Cellular   Disease   Surgery   at   K   Hospital

under microscope with magnification 400. The diagnosis results of

histopathological osteosarcoma based on criterion:

­ Cellular component of  osteosarcoma: polymorphic, diverse,

multi­size cells with abnormal cell division (multiple nuclei), dark

alkaline­colored nucleus.

­   Substrates   with   bone,   cartilage,   and   fiber   substances,   in

which bone subtances always exists.

Osteosarcoma   classification   is   made   according   to   the

classification table of WHO, 2002.

Before surgery, remove the tumor or amputate, perform a biopsy

at least twice:

+ The first time was implemented immediately after the patient

was   admitted   to   the   hospital   for   a   definitive   diagnosis   of

histopathology as osteosarcoma.

+ The second time: after the patient has 3 cycles of preoperative

chemotherapy   to   evaluate   the   histplogical   effect   of   treatment

according to 4 Huvos’s grades.

Grade IV:     100% necrosis (Complete response).

Grade III:     90 ­ 100% necrosis (Good response).

2.2.2. Bone scintigraphy

Grade II:      50­89% necrosis (Partial response). Grade I:       < 50% necrosis(No response).

Whole body bone scintigraphy is performed on SPECT (Single  Photon Emission Computed Tomography). 740 MBq 99mTc­MDP was

administered intravenously, and scintigraphic images were obtained

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after   3   hours.   Each   patient   with   osteosarcoma   was   taken   bone

scintigraphy at the following times:

First time: Immediately after diagnosis of osteosarcoma.  2nd time: after the end of 3 preoperative chemotherapy  according

to EOI regimen with the aim of comparing with pretreatment bone

scintigraphy, to detect new bone metastatic lesions, cell necrosis and

evaluate the Grade of respond to   chemotherapy, make comparision

of the suitability of two methods to assess preoperative chemotherapy

response.

­ Based on the grade of tumor cell necrosis through the biopsy

tissue.

­   Based   on   AR   (Alteration   Ratio)   value   through  bone

scintigraphy.

Evaluate the change in radiation uptake expressed by the TBR of  bone   scintigraphy  before   and   after   treatment.   The   TBR   is  determined as folows: TBR = (T­BG) /BG, in which: T is the count

of   radioactivity   at   the   tumor   and   BG   is   the   count   at   the   position

which is opposite to the tumor on the body (Background). Compared

pretreatment TBR (TBR1) with post­treatment TBR (TBR2), and the

change   was   defined   as   Alteration   Ratio   (AR).   AR(%)   =   (TBR1­

TBR2) /TBR1. The results of the alteration ratio were divided into

the   following   levels:   good   scintigraphic   respond   as     AR   ≥   60%;

partially respond AR 20 – 60% and not respond AR < 20%.

Comparing the results of assessing the treatment respond on bone

scintigraphy   with   the   assessment   effects   of   treatment   respond   by

assessing   tumor   cell   necrosis   through   biopsy   tissue   samples

according to Huvos.

­ Result:

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+   Normal   bone   scintigraphy:   Distribution   of   radioactive

pharmaceutical density according to physiological characteristics, not

detected   abnormally   on   bone   scintigraphy.   According   to   Otto

Sneppen,   TBR   >   1,5   which   is   diagnostic   threshold   of   malignant

lesion. Images on bone scintigraphy may be encountered:

+ "Hot zone" is the area of increased radiation uptake.

+ "Cold zone" is the area that reduces or loses radiation uptake.

+   Mixture:   Have   defects   in   central   area,   also   increasing

radioactivity in edging area.

+   Micrometastases   are   small   lesions   that   increase   radiation

uptake with TBR > 1,5.

2.2.3. Surgical treatment

­ Indication to amputation surgery.

+ No response to preoperative chemotherapy: AR index <20%, tissue

necrosis after chemotherapy < 50%.

+ The main invasive nerve vascular injury of the limb.

+ Biopsy causes the tumor cell to spread into a healthy tissue.

+  Amputation   surgery   also   indicates   that   there   are   too   many

lesions spreading to the soft tissue.

+   The   disease   is   more   advanced   before   chemotherapy:   Tumor

size increases, AR <20%, tissue necrosis after chemotherapy < 50%.

+ Relative indication: For patients who < 12 years old.

­ Indication surgery to remove the tumor: +  Response to chemothrapy: AR <20%, tissue necrosis after

chemotherapy ≥ 50%.

+ Do not invasive the main nerve and vascularity of the limb.

+ Enough soft tissue to ensure the minimum function of the limb.

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2.2.4. Chemotherapy

Chemotherapy before   surgery with EOI  regimen.   A  total   of   6

cycles (3 cycles before surgery and 3 cycles after surgery), each cycle

3 weeks apart.

After 3 cycles, a reassessment will be conducted, if:

­ AR ≥20%, tissue necrosis ≥ 50%, Follow­up with EOI regimen.

­   AR   <20%,   tissue   necrosis   <50%,   move   on   to   the   next   IE  regimen.   IE:   Ifosfamide   regimen   3000mg   /m2  skin   and   Etoposide  75mg/m2 skin intravenously injected from 1­4 days, 3­4 week cycle.

Surgery   are   performed   after   assessing   the   level   of   respond   to

chemotherapy. Surgery is done on the 9th week of treatment.

2.2.5. Treatment results

­ Early results: evaluated based on clinical indicators for 3 weeks

after surgery.

­ Late results: all research patients were allowed to have regular

re­examination according to the following:

+ First year: every 3 months.  + 2nd and 3rd year: every 6 months.

+ From the fourth year forwards: Once a year.

Information is recorded through follow­up examination:

+ Health status: good all over situation, non­recurring systemic

conditions, local and pulmonary X­rays, bone scintigraphy, CT scans

of the lungs to detect lung metastases.

+ Recurrency: there is an on­site lesion identified by X­rays, CT,

MRI, bone scintigraphy and pathological examination.

+   Detection   of   metastases:   by   X   ­rays,   CT,   MRI   and   bone

scintigraphy.

+ Relapse and metastasis status.

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+  Death:   reason  cause  of   death  related   to  osteosarcoma   (bone

metastasis, lung metastasis, brain metastasis).

+ Functional results of limbs

+ Evaluate the results of survival rate at different times: after 12

months, 24 months, 36 months. Overal survival rate: Patients with or

without relapse or metastasis.

The overal survival rate and survival rate without disease after 3

years, 5 years. Analysis of the relationship between overal survival

rate   by   single   factor   analysis:   invasion   level,   position   of   primary

tumor, X­ray lesion image, micrometastatic lesion before treatment...

Multi­factor analysis independently affects on survival rate: age,

gender,   tumor   size,   X­ray   lesions,   tissue   invasive   levels,

micrometastasis,   preoperative   alkaline   phosphatase   level   and   the

extent of tissue necrosis after preoperative chemotherapy.

2.2.6. Data Analysis

Using   SPSS   16.0   software   to   import   and   analyze   data.

Calculating   the   survival   results   according   to   Kaplan­Meier's   event

method. Using Log Rank test to calculate p value and factor analysis

affect   survival   rate;   Cox   regression   equation   to   calculate   p   value

when multi­factor analysis affects survival rate.

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CHAPTER 3: RESULTS

3.1. Clinical and subclinical characteristics of research patients         Table 3.1. Distribution of patients by age and gender (n=70)

Male Female Patients Rate (%) Age

≤ 10 2 3 5 7,1

11­20 28 17 45 64,3

21­30 9 5 14 20,0

> 30 2 4 6 8,6

Total 41 29 70 100

Osteosarcoma patients are more likely to be aged between 11 and

30  (84.3%).   The   youngest   patients   are  8  years   old  and  the  oldest

patients are 39 years old. Male/female rates were 1.42.

Table 3.3.Position of tumor (n = 70)

On the bone Rate Total Bone Meta­ (%)

Position of tumor

Diaphyse ends physes

21 8 5 48,6 34 Femur

11 0 5 22,9 16 Tibia

7 1 0 11,4 8 Fibula

5 3 0 11,4 8 Humerus

Other bones

1 3 0 5,7 4 (spinning bones,

pillars, slugs)

45 15 10 70 100 Total

The   femur   and   tibia   are   the   most   common   sites   having

osteosarcoma (48.6% and 22.9%, respectively).

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3.2. Image characteristics and the role of bone scintigraphy  3.2.1. Results of bone scintigraphy before treatment Table 3.10. Characteristics of lesions on bone  scintigraphy  before  treatment (n=70)

N Lesion in bone scintigraphy

Increase radiation uptake (hot spot) 69

Mixture 1

98.6%   of   patients   with   osteosarcoma   on   bone   scintigraphy

increase concentration of radioactive substances.

Results of bone scintigraphy before treatment of 16/70 patients

have detected with “leaping lesions”­micrometastases, (22.5%).

Table 3.11. Diagnose the stage according to Enneking (n = 70)

Stage diagnosis after bone scintigraphy Stage diagnosis before bone scintigraphy

Number of Stage IB IIA IIB III stage

IB 1 1

16 IIA 6 3

IIB 63 50

Leaping lesions has changed the stage: 16/70 of patients

Before bone scintigraphy, the clinical diagnosis combined with

CT scans and MRI have identified 1 patient with stage 1B, 6 patients

with stage IIA and 63 patients with stage IIB.

After  bone  scintigraphy, 16/70 (22.5%) patients with finding  "leap" lesions: 3 patients at stage IIA according to Ennecking and 13

patients at stage IIB into stage III.

3.2.2. Results of  bone  scintigraphy  evaluating the response

to preoperative chemotherapy

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Table   3.12.   Agreement   between   results   of   assessment   of

chemotherapy response through tissue necrosis according to Huvos   and AR index on bone scintigraphy (n = 57)

AR   change Tissue necrosis after chemotherapy Total

index ≥ 90% 50 – 90% < 50%

2 ≥ 60% 24 0 26

15 20­60% 3 3 21

0 < 20% 0 10 10

Total 27 13 57

17 χ2 = 72.8, Kappa = 0.779

The Kappa coefficient of these two evaluation is 0.779, ie there is

a close match between the two diagnostic methods.

Table 3.13. Response to chemotherapy on bone scintigraphy (n = 57)

Response to treatment n Ratio (%)

Good response (AR ≥ 60%) 26 45.6

Partial response and no response (AR < 60%) 31 54.4

Total 57 100.0

26 patients had an AR index of 0.6 (60%), corresponding to post­

treatment   tissue   necrosis   ≥   90%.   31   patients   (AR<0.6)   partially

responded and did not respond to preoperative chemotherapy.

3.2.3. Results of  bone scintigraphy  during the follow­up period

after chemotherapy

40  patients   took  bone  scintigraphy  (3rd  time),   conventional   X­ rays, CT scans and MRI before discharge and after 3 ­ 6 months (4 th  time) for follow­up of replase and metastasis.

Table 3.14. Finding relapse and metastasis on bone scintigraphy

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n = 40 Rate (%) Result of bone scintigraphy

24 Not change 60

12 Detecting relapse of lesions 30

3 Detecting metastasis 7,5

1 Recurrence + metastasis 2,5

40 Total 100

The   results   of   bone   scintigraphy   showed   that   there   were   12

patients with recurrence in the tumor, 3 patients with new metastases,

a patient had relapsed and metastasized. Meanwhile, by clinical, X

rays, CT and MRI only detected 8 recurring patients and 1 patient

with metastases.

3.3.4.   Treatment   results   and   factors   affecting   the   treatment

results

3.4.2.The rate of relapse and metastasis

Table 3.19. Relapse and metastasis (n = 70)

ỷ ệ n Results after treatment T  l (%)

17 Relapse 24,3

12 Metastasis 17,1

41 No relapse or metastasis 58,6

17   patients   with   osteosarcoma   and   early   recurrence   within   6

months   after   treatment   accounted  for   24.3%.   12  patients   appeared

metastasis (17,1%).

3.4.3. Results of limb function (at the end of the research)

15/46   patients   undergoing   conservative   surgery   were   local

recurrence,   including:   12   were   amputated,   3   patients   continued

surgical   treatment   preserved   by   removing   the   recurrence   of   the

tumor. With the remaining 34 patients, at the last visit of research,

17

there were only 24 patients still alive ­ The results of the evaluation

function were as follows:

Table 3.20. Results of limb function (n = 24)

Results of limb function n Rate %

Very good 6 25,0

Good 9 37,5

Average 6 25,0

Poor 3 12,5

62,5% of function of limb is good and very good.

3.4.4. Survival rate

The shortest survival rate is 8 months; the longest follow­up time

is 72 months. By Kaplan­Meier method show that the 1­year overal

survival   rate   is   94.3%,   2­years   overal   survival   rate   is   83.1%,   the  overall survival rate remains unchanged from the 4th year.

3.4.5.7. Multi­variable analysis of the relationship between extra  life and related factors

Stand

errors

of

Variables

Degree

Coeff  β

Risk  ratio

Confidence  interval 95%

Bậ c tự  do

Wald  test (X2  test)

coeff  β

Low

High

0,67

Sex

1,034

2,368

0,124

0,356

0,095

1,327

1

2

0,59

Children/  Aldult

0,025

0,002

0,967

0,975

0,301

3,157

1

9

0,66

Tumor size

0,721

1,184

0,277

2,057

0,561

7,539

1

3

0,125

,512

0,059

0,808

0,883

0,324

2,406

1

0,64

0,310

0,229

0,632

1,363

0,383

4,856

1

8

0,57

Bone  resorption or  bone  formation  The level of  soft tissue  invasion Leap  metastasis

1,805

9,902

0,002

6,077

1,975

18,699

1

3

0,42

0,200

0223

0,637

0,819

0,357

1,877

1

Photphataza  alkaline

3

0,55

0,329

0,354

0,552

1,390

0,469

4,117

1

4

Cancer tissue  necrosis after  chemotherap y

18

The bad prognostic factors related to the survival rate of patients

is leap lesion­micrometastases before treatment.

19

CHAPTER 4. DISCUSSIONS

4.1. Clinical and subclinical characteristics of research patients

Primary   bone   cancer   osteosarcoma   is   the   most   common

malignant   disease   in   adolescence.   Patients   in   this   reasearch   were

aged between 11 and 20 years and ther are more men than women.

Research   made   by  a  number   of   domestic   authors   such  as   Le   Chi

Dung (69.3%), Tran Van Cong (60%) and Vo Tien Minh (59.1%) is

the proportion of cases in the age of 10­20.

The most common age in this research group is 11­30 years old

(accounting for 84.3%). This result is also consistent with studies of

domestic and foreign authors.

The   age   of   the   patient   is   also   significant   in   the   prognosis.

According to Emilios P. et al., the older the patient is, the overal

survival rate is reduced (increased risk of mortality rate of 7% for

patients with age difference of more than 10 years).

4.2.The bone scintigraphy in diagnosis, treatment and monitoring

of osteosarcoma treatment

4.2.1. Bone scintigraphy detected metastases before treatment

Among 70 patients in our research, bone scintigraphy was taken

before treatment. Results found that 16/70 patients (22.5%) had 1­2

lesions   of   over­joint   leap   lesion.   These   micrometastatic   lesions

changed the stage diagnosis of 16 patients from stage II to stage III.

In 1990, Wuisman and Enneking found 23 osteosarcoma patients

with micrometastasis and 224 patients who did not metastasis. The

authors considered classifying the case of micrometastasis to distant

metastases because there is a significant difference in follow­up after

surgical   and   chemotherapy.   22/23   patients   have   leaping

20

micrometastatic had local recurrence, distant metastasis  and death,

leaving only 1 patient has not relapsed for 38 months.

In 2006, Kager . et al. studied 1,765 patients with high malignant  osteosarcoma and found 24 patients with micrometastasis, accounting

for   1.4%.   The   authors   noted   that   bone  scintigraphy  is   a   valuable

method for early detection of leap metastases, detecting discordant

metastatic lesions which are difficult to be detected by CT/ MRI.

4.2.2. The role of bone scintigraphy in assessing chemotherapy

response

57 cases of osteosarcoma treated with chemotherapy for 3 cycles

EOI + surgery + after chemotherapy  for 3 cycles. After 3 cycles of

EOI, patients were evaluated for the withdrawal of cancer due by two

objective measures such as tumor biopsy assessing tumor necrosis

grade according to HUVOS and the AR index of  bone scintigraphy.

Among 28 patients (tab. 3.8) with necrotic cancer cells due to

chemotherapy  ≥ 90%, 24 patients has an AR index > 60% while only

4 patients have an AR index  <60%. In contrast, among 29 patients

with chemotherapy   necrotic cancer <90%, 2 patients had an AR  ≥

index of 60% while up to 27 patients had an AR index  <60%. There

is a clear similarity, match through the assessment of necrotic cancer

cells by HUVOS on pathology and AR index on bone scintigraphy.

In 1990, Knop at all used bone scintigraphy of  99mTc­MDP to

evaluate the effectiveness of preoperative chemotherapy  response for

30 patients with osteosarcoma and found that there was an 88% fit

between   good   response   on   bone   scintigraphy   and   grade   of   cell

necrosis ≥ 90% and 96% fit for poor response on bone scintigraphy

with tumor necrosis grade <90%.

21

In   1998,   Kobayashi   reported   the   results   of   bone   scintigraphy

analysis   of   34   patients   with   osteosarcoma.   Cancer   tissue   necrosis

after preoperative chemotherapy  is divided into 4 grade according to

Huvos. Patients with AR  ≥ 60% respond well. Among 17 patients

with good histological response, 13 patients showed a good response

to bone scintigraphy. The average AR of these 17 patients is 68%.

The   AR   index   of   17   patients   was   positively   correlated   with

histological effect. 17 patients did not respond with an average AR

index   of   ­9.9%.   The   author   found   that   the   AR   change   of   bone

scintigraphy   is   closely   related   to   cancer   cell   necrosis   after

chemotherapy.

Another  advantage  of  bone scintigraphy is that,  in addition to

assessing   the   tumor's   local   therapeutic   response   via   TBR,   bone  scintigraphy is also able to detect metastasis and relapse early if any.

4.3. Treatment results

4.3.1. Results of survival rate

Results of follow­up of survival rate of 70 patients at the end of

research, 53 patients were still alive and 17 patients died. Among 53

alive patients, 17 patients lived ≥ 60 months, 10 patients lived ≥ 48

months, 14 patients lived ≥ 36 months, 8 patients lived ≥ 24 months,

4 patients lived<24 months. Among 17 patients with reported death:

4 patients died in the first year, 8 patients died in the second year, 5

patients died in the third year after treatment. Causes of death of 17

patients: 11 patients died due to relapse, 4 patients died of metastasis

without relapse, 2BN died due to relapse and metastasis. The overal

one­year   survival   rate   of   research   group   is   94.3%;   overal   2­year

survival rate of research group is 82.8%. Have not detected patients

22

died from the 36th months onwards since the beginning of treatment

intervention.

Vo Tien Minh, with a simple surgical treatment of osteosarcoma,

results in a total survival of only 1 year of 32%, 2 years of 29.9%,

after 3 years and 5 years of 19.9%. Research of Tran Van Cong at

Hospital K for 95 patients with osteosarcoma, treatment of surgery

combined with chemotherapy of doxorubicin and cisplatin with the

overall 3­year survival rate was 69.2%, for 5 years was 62,6%.

Bacci   G.   and   his   colleagues   followed   46   patients   with

osteosarcoma,   34   patients   who   had   preserved   surgery   and

amputation, 12 patients combine with chemotherapy   achieved a 5­

year  survival  rate  of  59%.  Cai  Y.  treated  170  patients:  Combined

chemotherapy before and after surgery for 104 patients, 66 patients

having surgery only. The 5­year and 10­year survival rates were 61%

and 53%, respectively, in the combined treatment group, while those

in the surgical only group were only 28% and 26%.

Goorin   et   al.   (1996)   compared   the   regimen   of   high­dose

methotrexate,   leucovorine,   doxorubicin,   cisplatin,   bleomycin,

cyclophosphamide   and   dactinomycin   to   the   treatment   of

osteosarcoma   in   un­metastatic   children.   Group   1   has   45   pre­

chemotherapy   patients, group 2 had 55 patients who had surgery

first. The result of 5­year disease­free survival in group 2 is 65%, that

of group 1 is 61% with p = 0.8.  4.3.2. Relapse and metastasis after treatment

17   patients   were   recurrent   locally,   accounting   for   24.9%.

Recurrence occurred early, within 6 months, reached the remaining

20%   and   about   4%   was   later   recurrence.   Of   which   15   patients

relapsed after limb­sparing surgery.

23

12   patients   did   not   have   recurrence   in   place   but   had   distant

metastasis,   mainly   lung   metastases   (88.3%),   bone   metastases   (2

patients), especially 2 patients who have both bone metastases and

lung metastases. Mostly metastases appear within 12 months.

In 1996, Wirtz from 1978 to 1992 treated and monitored patients

with osteosarcoma, results: 28 patients relapsed, of which 7 patients

relapsed   locally   and   21   patients   relapse   with   distant   metastases,

mainly lung metastases. Most relapses occur in the first 4 years of

follow­up.

Frassica et al, with bone cement filling application, found that the

mechanical   strength   of   bone   defects   has   been   demonstrated   to

recover  up to  98%.  In  addition,  the heat  generated  during cement

hardening creates a thermal effect around the lesion and reduces the

recurrence rate. In the study of Kivioja and colleagues, recurrence

rate of 147 patients with tumors cleaning out and cement filling was

22%, 47 patients with tumors cleaning out and bone cement filling

application have recurrence rate of 52%.

4.4. Factors affecting treatment results

Using COX regression analysis method, variables such as sex,

age   of   children   or   adults,   tumor   size,   bone   resorption   or   bone

formation on X­ray film, level of soft tissue invasion, leap metastasis,

alkaline   phosphatase   assay,   classification   of   tumor   tissue   necrosis

after chemotherapy...The analytical results show that only the leap

metastasis factor is statistically significant with p <0.05.

In   2002,   Bielack   and   colleagues,   study   1,702   osteosarcoma

patients with surgical and chemotherapy. It showed that the overall

10­year survival rate were 59.8% and survival rate without disease

for 10 year is 48.9%. Survival rate of having metastasis is 26.7%,

24

Survival   rate   without   having   metastasis   is   64.4%.   By   multi­factor

analysis,   the   author   found   that   the   independent   prognostic   factor

which   adversely   affected   survival   rate   was   tumor   position   and

metastasis.

In  2006,   Bacci   et   al.   Studied  789   patients   with   osteosarcoma.

Multifactorial   analysis   showed   independent   prognostic   factors

adversely affecting survival of age <14, tumor size  ≥ 200ml, poor

response of histology.

By   single   analysis   of   the   effect   of   additional   survival   results

allowed   to   get   2   prognostic   factors   having   statistical   significance

with p <0,05 is the leap metastasis and the disease stage.

By taking multi­variable analysis according to the regression of

COX,   we   found   that   the   changable   factor   metastasis   is   an

independent prognostic factor affecting survival for 3 years having

statistical significance with p <0.05.

25

CONCLUSIONS

1/   Bone  scintigraphy  plays   a   role   in   diagnosing   leap

metastases, assessing the preoperative chemotherapy response

­   The   bone  scintigraphy  detected   16/70   osteosarcoma   patients

with   micrometastasis,   accounting   for   22.8%.   The   finding   of   leap

metastasis helps to classify the stage of disease more accurately: 16

patients with stage II when detecting the leapmetastasis are changed

into stage III according to Enneking's classification.

­   Bone  scintigraphy   of  57   osteosarcoma   patients   with   EOI

preoperative   chemotherapy   to   assess   cancer   response.   26   patients

corresponds   well   to   chemotherapy   with   AR   index   of   bone

scintigraphy ≥ 60%, accounting for 45.6%; 31 patients  corresponds

to   chemotherapy   with   AR   index   of   bone  scintigraphy<60%,

accounting   for   54.4%.   Comparing   with   HUVOS   classification   for

cancer   necrosis   due   to   ≥   90%   and   <90%,   it   shows   that   bone

scintigraphy  is   matching   for   HUVOS   classification   and   cancer

responds   well   to   chemotherapy   when   radiation   uptake   is   much

reduced, and vice versa, cancer response not well with chemotherapy,

radiation   uptake   is   reduced   less.   The   agreement   between   the   AR

index and HUVOS necrosis on the biopsy cancer after chemotherapy

is consensus, having statistical significance with p <0.05.

2/ Evaluation the results of combined surgical treatment with

osteosarcoma

70   Patients   with   osteosarcoma   were   treated   with   surgical

combination with chemotherapy EOI regimen: For 24 patients having

amputation   and   46   patients   undergoing   preservation   surgery,   the

results are as follows:

­ A 3 years survival rate based on Kaplan­Meier is 75.7%.

26

­   The   survival   rate  of   3  years   without   disease  (non­relapsing)

according to Kaplan­Meier is 48.5%.

­   The   rate   of   recurrence   within   3   years   according   to   Kaplan­

Meier is 24.9%. Relapses usually occur within 6 months to 1 year,

less relapse from 2 to 3 years.

­   The   rate   of   distant   metastasis   within   3   years   according   to

Kaplan­Meier is 19.4%. Metastasis occurred not much within 1 year,

but scattered in the second and third years after treatment.

­ One variable analysis affecting Kaplan­Meier's 3­year survival

time showed the leap metastasis factor. Patients with osteosarcoma

having   leap   metastasis,   3   years   of   survival   rate   are   50.8%   while

patients   without   osteosarcoma   having   leap     metastasis   3   years   of

survival rate are 79.7% (p<0.05). Patients with stage III osteosarcoma

and 3 years of survival rate are 50.8% while patients with stage III

osteosarcoma and 3 years of survival rate are 79.4%. (p <0.05).

­   Multi­variable   analysis   affecting   the   3­year   survival   rate

according to COX regression showed that the leap metastasis factor

is an independent prognostic factor affecting the 3­year survival rate

and having statistically significant with p <0.05.

27

LIST OF WORKS RELATED TO THE THESIS HAS BEEN PUBLISHED

1. (2015)  Trinh Van Thong, Nguyen Danh Thanh, Pham  Đang  Ninh.  The   role   of   bone   scintigraphy   in   diagnosis   and   treatment  osteosarcoma.Vietnam Medical Journal, June (2), pp. 32­36.

2.(2016)  Trinh Van Thong, Nguyen Đai Binh. Prognosis factors  and treatment outcome of  osteosarcoma: An analysis of 70 patients.

Journal of Military Pharmaco­medicine, (3), pp. 149­154.