There is a low papillary to follicular ratio in iodine deficient areas. A study of malignant thyroid tumors done over a period of 4 years in Goa shows that the ratio of papillary to follicular carcinoma in Goa conforms to a iodine deficient status of the population

Arora, Dr Raman

Dias, Dr Avril

English

CogPrints Cognitive Sciences Eprint Archive

Iodine and Thyroid Cancer in Goa

Raman Arora

Avril Dias

Directory of Open Access Journals

Cognitive Sciences ePrint Archive

OJHAS  Vol 5 Issue 4(3) -   Arora R, Dias A. Iodine and Thyroid Cancer in Goa
Published Quarterly
Mangalore, South India
ISSN 0972-5997
Volume 5, Issue 4; Oct -Dec 2006
Iodine and Thyroid Cancer in Goa 
Authors
Raman Arora
Junior Resident, Goa Medical College, Bambolim, Goa
Avril Dias
Associate Professor, Department of Pathology, Goa Medical College, Bambolim, Goa  
Address For Correspondence
Dr. Raman Arora 
House No 305, Chandgi ram block,
Asiad village complex, Delhi-110049, INDIA
E-mail: drramanaiims@gmail.com
Citation
Arora R, Dias A. Iodine and thyroid cancer in Goa Online J Health Allied Scs.2006;4:3 
URL
http://www.ojhas.org/issue20/2006-4-3.htm
Open Access Archives
http://cogprints.ecs.soton.ac.uk/view/subjects/OJHAS.html
http://openmed.nic.in
1
Submitted: Feb 8, 2007; Suggested Revisions: Feb 14, 2007; Revised: Mar 9, 2007; 
Suggested Revisions: Mar 20, 2007; Revised: Mar 24, 2007;  Accepted: Mar 26, 2007 
Short Article
OJHAS  Vol 5 Issue 4(3) -   Arora R, Dias A. Iodine and Thyroid Cancer in Goa
Abstract:
There  is  a  low  papillary  to  follicular 
ratio in iodine deficient areas. A study 
of malignant thyroid tumors done over 
a period of 4 years in Goa shows that 
the  ratio  of  papillary  to  follicular 
carcinoma in Goa conforms to a iodine 
deficient  status  of  the  population.
Key  Words:  Iodine,  Thyroid 
carcinoma, Papillary, Follicular  
Introduction:
The  most  frequent  endocrine 
malignancies  are  thyroid  carcinomas 
accounting  for  approximately  0.5–10 
cases per  100,000 population.(1)  The 
overall incidence of thyroid carcinoma 
is  generally  not  considered  to  be 
influenced  by  iodine  intake  of  a 
population  whereas  distribution  of 
types  of  differentiated  thyroid 
carcinoma may be related to intake of 
iodine.(2) In areas of iodine deficiency, 
relative  frequency  of  follicular 
carcinoma  is  high,  but  overall, 
papillary  carcinoma  remains  higher 
and there is a low papillary to follicular 
ratio in iodine deficient areas.
Materials  and  Methods:
The study of malignant thyroid tumors 
was  done  over  a  period  of  4  years 
(2000-2003).  All  thyroid  tumors  were 
derived  from  unselected  surgical 
material  sent  to  the  department  of 
Pathology,  Goa  medical  college, 
Bambolim,  Goa  from the  department 
of  Surgery  and  various  private 
surgeons.  The  thyroids  of  surgical 
material were grossed and histological 
sections  were  prepared  from  every 
macroscopic  lesion  suspected  to  be 
malignant.  As  necessary,  additional 
sections  of  available  material  were 
prepared and special stains employed, 
in  particular  congo  red  to  identify 
medullary  carcinoma.  Histological 
diagnosis  was  made  on  light 
microscopic  examination.  WHO 
international  classification  was 
followed  for  typing  the  thyroid 
malignant thyroid tumors. 
Results 
Among  31815  specimens  received 
over  a  period  of  4  years,  620  were 
thyroid specimen and among them we 
found  66  malignant  thyroid  tumors. 
Papillary carcinoma was most common 
(54.55%)  of  all  classified  malignant 
thyroid  tumors  exceeding  follicular 
(36.37%)  and  medullary  (6.06%) 
lymphoma  (1.51%)  and  anaplastic 
carcinoma  (1.51%).  The  papillary  to 
follicular carcinoma ratio was 1.5:1.
Table 1: Histological classification 
of malignant thyroid lesions
Histological  
Type
Number of 
malignant 
thyroid 
tumors
% of total 
thyroid  
malignancies
Papillary 
carcinoma
36 54.55%
Follicular 
carcinoma
24 36.37%
Medullary  
carcinoma
4 6.06%
Lymphoma 1 1.51%
Anaplastic  
carcinoma
1 1.51%
Total 66 100%
Discussion:
Findings of the present study revealed 
low  papillary  to  follicular  carcinoma 
ratio and relative higher  incidence of 
follicular  carcinoma.  Various  studies 
like Ezaki Haruo et al 1992 (papillary-
78.4%, follicular  -  17.2%,  papillary to 
follicular ratio 4.6)(3), Segovia Gomez 
et  al  (Papillary  –76%,  follicular  –18%, 
papillary  to  follicular  ratio  –4.2)(4), 
Harach  et  al  (papillary  to  follicular 
ratio-6.2)(5)  revealed  relative  lower 
follicular  carcinoma  and  higher 
papillary  to  follicular  carcinoma ratio. 
Williams  et  al  (6)  found  a  relatively 
higher  frequency  of  follicular 
carcinoma in Cali and Manddoza goiter 
endemic  areas,  with  papillary  to 
follicular  carcinoma ratio  being 1.3:1, 
and  0.9:1  respectively.  In  Northeast 
Scotland  and  Iceland  (iodine  rich 
areas)  the  ratio  is  3.6:1  and  6.5:1 
respectively.(6)
2
OJHAS  Vol 5 Issue 4(3) -   Arora R, Dias A. Iodine and Thyroid Cancer in Goa
The  histological  pattern  of  malignant 
thyroid tumors in our study in Goa is 
following  the  histological  pattern  of 
iodine  deficient  places.  Goa  is  a 
coastal  area  and  people  consume 
seafood  rich  in  iodine.  But  a  survey 
conducted  by  National  Goitre  Control 
Survey Team (NGST) in Goa reported 
total  goiter  rate  (TGR)  of  34.9% 
in1993.(7)  A  study  by  Kapil  et  al 
conducted  in  Tiswadi  block  of  Goa 
found total goiter rate of 16.6%.(8) The 
median urinary iodine was 5.5 mcg per 
100  ml  indicating  moderate  iodine 
deficiency  amongst  the  population 
studied.(8)  They  also  surveyed  salt 
sample and found that  48.9% of  salt 
sample did not have any iodine.(8,9) A 
possibility  of  goitrogens  present  in 
food of coastal places like Panaji  was 
also suggested by Kapil et al 
From  our  own  work  and  parallel 
evidence  already  quoted  we  would 
conclude that a low dietary intake of 
iodine  is  associated  with  a  low 
papillary  to  follicular  carcinoma ratio. 
We would also like to conclude that the 
histological  pattern  of  thyroid 
carcinoma in Goa is compares with the 
histological  pattern in iodine deficient 
area,  supporting the findings of  Kapli 
et  al.(8)  The  authors  want  to  stress 
that Goa needs an urgent and detailed 
study  of  iodine  deficiency  disorders 
and iodisation status.
Conclusions:
Our  study  shows  that  the  ratio  of 
papillary to follicular carcinoma in Goa 
conforms to a iodine deficient status. 
Further  investigations  are  needed  to 
assess  the  overall  iodine  status  of 
population in Goa and need for urgent 
iodine prophylaxis.
References:
1. Chan KC,  John.  Tumors of  thy-
roid  and  parathyroid  gland.  In 
Fletcher CDM Editor. Diagnostic 
histopathology  of  tumors.  2nd 
edition.  London:  Churchill  Liv-
ingstone. 2000.
2. Rasmussen-Ulla  Feldt.  Iodine 
and  cancer.  Thyroid 
2001:11;483-486. 
3. Ezaki Haruo, Ebihara Satoshi et 
al.  Analysis  of  thyroid  carcino-
ma  based  on  material  regis-
tered  in  Japan  during  1977-
1986 with special  reference to 
predominance of papillary type. 
Cancer 1992:70; 808-814. 
4. Segovia Gomez I, Gallowitsch HJ 
et al.  Descriptive epidemiology 
of  thyroid  carcinoma  in  Car-
rinthia,  Austria:  1984-2001. 
Histopathologic features and tu-
mor classification of 734 cases 
under  elevated general  iodina-
tion  of  table  salt  since  1990: 
Population based age stratified 
analysis  on  thyroid  carcinoma 
incidence.  Thyroid 2004:4;277-
286. 
5. Harach HR,  Williams ED.  Glan-
dular  (tubular  and  follicular) 
variants  of  medullary  carcino-
ma of the thyroid. Histopatholo-
gy 1983:7;83-97. 
6. Williams et al. Thyroid cancer in 
an  iodine  rich  area.  A 
histopathological study.  Cancer 
1977;39:215-222. 
7. The National Goitre control pro-
gramme. A blue print for its In-
tensification.  Nutrition  founda-
tion  of  India  scientific  report. 
New Delhi 1983 pp36-38 
8. Kapil  et  al.  Assessment  of  io-
dine deficiency in Tiswadi block, 
Goa Indian practitioner vol XLIX 
no 9, 749-750.   
9. Kapil U. Current status of iodine 
deficiency disorders.  Indian Pe-
diatr 1998;35:831-836 
3


Tumors of thyroid and parathyroid gland. In Fletcher CDM Editor. Diagnostic histopathology of tumors. 2nd edition.

http://doaj.org/search?source=%7B%22query%22%3A%7B%22bool%22%3A%7B%22must%22%3A%5B%7B%22term%22%3A%7B%22id%22%3A%2235b26f58670e426a92ba43f2634ce3b8%22%7D%7D%5D%7D%7D%7D

Iodine and Thyroid Cancer in Goa

Abstract

Similar works

Full text

Available Versions

CogPrints Cognitive Sciences Eprint Archive

Directory of Open Access Journals

Cognitive Sciences ePrint Archive