Yu. Demidchik, M. Fridman
Childhood Thyroid Cancer in Belarus Following the Chernobyl Accident
Part 1
THYROID CANCER STATISTICS– Two etiological forms (radiogenic and sporadic)– High incidence in children within the first decade after
Chernobyl• Since 2001, only sporadic cases were diagnosed
– Prevalence of PTC• Follicular, medullary or anaplastic carcinomas are extremely
rare– Recently, about 50% of patients present micro
carcinomas at diagnosis
Crude incidence and mortality for thyroid cancer (:100 000) (1965–2013)
19651967
19691971
19731975
19771979
19811983
19851987
19891991
19931995
19971999
20012003
20052007
20092011
20130
2
4
6
8
10
12
14In total, 23795 patients were diagnosed from 1970
Mortality rates are available only since 1990
(1747 patients died within 1990-2013)
Crude incidence and mortality for thyroid cancer in males (:100 000) (1970–2013)
19701972
19741976
19781980
19821984
19861988
19901992
19941996
19982000
20022004
20062008
20102012
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
Crude incidence and mortality for thyroid cancer in females (:100 000) (1970–2013)
19701972
19741976
19781980
19821984
19861988
19901992
19941996
19982000
20022004
20062008
20102012
0
5
10
15
20
25
Incidence increased by 8 times as compared with 1986
19701973
19761979
19821985
19881991
19941997
20002003
20062009
20120
5
10
15
20
25
30
BrestVitebskGomelGrodnoMinskMogilevMinsk city
Crude incidence (: 100 000) for thyroid cancer in different regions (1970–2013)
0.00
5.00
10.00
15.00
20.00
25.00
30.00
00-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80+
Crude incidence (: 100 000) for thyroid cancer depending on age group (1970–2013)
Part 2
THYROID CANCER IN CHILDREN– 1418 cases of thyroid carcinomas (under 19 y.o.)
were diagnosed in the period from 1986 and 2010 (all histological forms).
– Of them, 1169 are available for assessment.– The individuals born after April, 1987 were
considered as non-radiogenic.
00,20,40,60,8
11,21,41,61,8
2
1986 1987 1988 1989 1990
Cru
de in
ciden
ce 1
05
years
The beginning of significant increase of incidence in exposed to 131I
0
1
2
3
4
5
6
1986 1987 1988 1989 1990 1991 1992C
rude
incid
ence
105
years
Aged under 18 Aged over 19
19701972
19741976
19781980
19821984
19861988
19901992
19941996
19982000
20022004
20062008
20102012
0.00
2.00
4.00
6.00
8.00
10.00
12.00
14.00
16.00
00-14 15-19 20-24 25-29
?
Crude incidence (: 100 000) in young age (1970–2013)
19701973
19761979
19821985
19881991
19941997
20002003
20062009
20120
2
4
6
8
10
12
14
BrestVitebskGomelGrodnoMinskMogilevMinsk city
Childhood crude incidence (: 100 000) for thyroid cancer in different regions (1970-2013)
19701973
19761979
19821985
19881991
19941997
20002003
20062009
20120
5
10
15
20
25
30
35
40
BrestVitebskGomelGrodnoMinskMogilevMinsk city
Adolescent crude incidence (: 100 000) for thyroid cancer in different regions (1970-2013)
Post Chernobyl thyroid cancer cases in children depending on place of residence at the time of Chernobyl accident (1986-2005)
Thyroid cancer in Belarus Results of Screening
Study Area Age group PeriodCases Prevalence
male female Total male female Total
IPHEKA (Scientific report, 1996) Gomel region
Children and adolescents at the time of accident
1990–1992 — — 15 — — 15/6946
2.16/1000
Sasakawa (Proceedings of the 5th Chernobyl Sasakawa Medical Cooperation Symposium, 1996)
Gomel region
Up to 9 years at the time of accident
1991–1996 12 25 37 12/9485
1.27/100025/101752.46/1000
37/196601.88/1000
Sasakawa (Proceedings of the 5th Chernobyl Sasakawa Medical Cooperation Symposium, 1996)
Mogilev region
Up to 9 years at the time of accident
1991–1996 1 1 2 1/11663
0.09/10001/12118
0.08/10002/23781
0.08/1000
Belarus screening program (Drozd V. M., 2003) Belarus
Up to 14 years at the time of accident
1990–1991 — — 7 — —
7/11006.36/1000
Belarus screening program (Krysenko N. A., 2003)
Gomel region
Up to 14 years at the time of accident
2002
— — 0 — —0/254460/1000
15–18 years at the time of accident
— — 2 — —2/12129
0.17/1000
1999 2000 2001
n 151015 150381 144765
NODULES542 495 393
0.36% 0.33% 0.27%
OF THEM CANCER
10 9 3
1.85% 1.82% 0.76%
CHILDREN (under 15)
17
1999 2000 2001
n 44859 49064 57068
NODULES513 547 655
1.14% 1.11% 1.15%
OF THEM CANCER
6 11 21
1.17% 2.01% 3.21%
ADOLESCENTS (15–18 yo)
1999 2000 2001
n 96928 100169 80541
NODULES7405 7635 7195
7.64% 7.62% 8.93%
OF THEM CANCER
299 298 237
4.01% 3.92% 3.29%
ADULTS (19+ yo)
POST CHERNOBYL (RADIOGENIC) PATIENTS-1
Total number of cases: 936 (non-PTC cases and irradiated previously for other malignancies excluding)
– Females: 600 (64.1%)– Males: 336 (35.9%)– Ratio: 1.8:1
Age: 4.2 – 18.99 (13.6)– Under 10 y.o.: 157 (16.8%)– 11-14 y.o.: 364 (38.9%)– 15-18 y.o.: 415 (44.3%)
POST CHERNOBYL (RADIOGENIC) PATIENTS-2
• Tumor size– Average: 14.4 mm (range 1-124 mm)
• From 1 to 5 mm: 84 cases• From 6 to 10 mm: 302 • Above 11 mm: 550 (58.8%)
• Involved lymph nodes– N0 :246 (26.3%)– N1a:309 (33.0%)– N1b:381 (40.7%)
(41.2%)
(73.7%)
POST CHERNOBYL (RADIOGENIC) PATIENTS-3
• Distant metastases at primary diagnostics — 104 (11.1%).
• Extrathyroidal extent – 387 (41.3%). !Note!
In 262 (28.0%), the capsular involvement is not assessed.
• Multifocality – 60 (6.4%)
POST CHERNOBYL (RADIOGENIC) PATIENTS-4
• Pathological features– Classical PTC – 360 (38.5%)– Follicular variant – 292 (31.2%)– Diffuse sclerosing variant – 73 (7.8%)– Tall cell – 65 (6.9%)– Clear cell – 10 (1.1%)– Solid – 136 (14.5%)
• Involved blood vessels – 176 (18.8%)• Involved lymphatic vessels – 790 (84.4%)
POST CHERNOBYL (RADIOGENIC) PATIENTS-5
• Thyroid background – 148 (15.8%), including– Autoimmune thyroiditis – 72– Follicular adenoma – 20– Nodular goiter – 56
• Dominant architectonics – Papillary – 300 (32.1%)– Follicular – 453 (48.4%)– Solid – 183 (19.6%)
CONCLUSION#1
Post Chernobyl (radiogenic) PTC is frequently extrathyroidal. The tumor size in largest measurement is usually small but associated with high frequency of neck lymph nodes involvement (73.7%) and distant metastases (11.1%)
TOTAL THYROIDECTOMY+
BILATERAL SELECTIVE NECK DISSECTION (LEVELS VI, II-IV)
RADIOIODINE UPTAKE I-131
RADIOIODINETHERAPY
L-T4SUPRESSIVE THERAPY
Multivariate analysis of local or regional recurrence
Variables β p-value RR 95% CI
Age at surgery 0.5855 0.1041 1.80 0.88-3.64
Multifocal carcinomas 1.0762 0.0049 2.93 1.39-6.21
N1b 0.5920 0.0361 1.81 1.04-3.14
Involved blood vessels 0.4734 0.0976 1.61 0.92-2.81
Involved lymphatic vessels 1.2845 0.0900 3.61 0.82-15.95
Thyroid background -1.0669 0.1461 0.34 0.08-1.45
Intrathyroidal dissemination 0.6483 0.0309 1.91 1.06-3.45
Thyroid lobectomy 1.8122 <0.0001 6.12 3.38-11.11
The risk of recurrence
CONCLUSION#2
• Local or regional recurrence after thyroidectomy is likely for 5 years and distant metastases can spread for 6 years.
• In cases of surgery other than thyroidectomy, the probability of local or regional recurrence is high in any terms of follow-up.
• Distant metastases can be detected within 10 years after partial thyroid resections.
Fine Grey regression model for distant metastases
Variables β p-value RR 95% CI
Childhood age at surgery 6.13 0.0150 6.13 1.43 – 26.3
Involved blood vessels 2.16 0.0002 8.68 2.75 – 27.4
No RIT 2.23 0.0003 9.26 2.74 – 31.2
CONCLUSION#3
• To avoid local or regional recurrence in children and adolescents with PTC, primary surgery has to be based on total thyroidectomy followed by radioiodine therapy depending on indications
• Despite this strategy, distant metastases can appear 5-6 years after surgery being associated with tumor peculiarities: involved blood vessels, patients’ age and refusal from radioiodine
Part 3
SPORADIC THYROID CANCER IN CHILDREN
No clear evidence of geographical factor in sporadic cases (n=210; 1986–2010)
Differences between sporadic and radiogenic cancer
Sporadic carcinomas were significantly more common on abnormal thyroid background.
In sporadic cases, lung metastases are significantly less common as compared with radiogenic carcinomas (2 cases; 1.4%).
Crude incidence in different periods and age groups
Age groupRadiogenic Sporadic
1990–1995 1996–2001 2002–2005 2005–2010
0–18 2.72 3.22 1.29 1.16
0–14 2.88 2.24 0 0.62
15–18 2.09 6.24 4.48 2.54
Observed survival (96.9%)
0 2 4 6 8 10 12 14 16 18 20 22 24 26 280
10
20
30
40
50
60
70
80
90
100
p=0.8763
Годы
ОВ
, [%
]
Causes of death in 26 pts
• Cause specific death: 2• Acute leukemia: 2• Gastric cancer: 1 (totally 10 pts have second cancer)• Accidents and traumatic lesions: 6• Suicide: 7• Surgical complications: 1• Lung fibrosis: 1 • Liver cirrhosis: 1• Cardiac failure: 1 +2 sporadic• Mixedema: 1 • Brain infarction: 1
CONCLUSION#4
The prognosis in childhood and adolescent thyroid cancer is favorable.
Acknowledgment
• Dr. Yu. Averkin • Prof. D. Williams• Prof. K. W. Schmid• Prof. C. Reiners• Dr. M. Fridman• O. Krasko
THANK YOU
FOR ATTENTION!