Histomorphological Study of Thyroidectomy Specimens in Tertiary Care Hospital -A Retrospective Study

Abstract

Thyroid disorders are the most common endocrine disorder affecting the general population. Diseases of the thyroid glands present with either an alteration of hormone secretion or as an enlargement of the thyroid gland. They vary from non-neoplastic to neoplastic lesions. The prevalence and pattern of these disorders depend on the factors like age, sex and geographic patterns. The aim of the study is to determine the histomorphological features of thyroid lesions in thyroidectomy specimens in patients who underwent thyroidectomy in tertiary care hospital. This is a retrospective study, conducted in tertiary care centre attached to government hospital. All thyroidectomy specimens received in the Department of Pathology, from January 2021 to January 2023 were included in the study. The patients who underwent thyroidectomy in view of thyroid swelling, over a period of 2 years, were selected. Data was collected from histopathological examinations done on the thyroidectomy specimens. Different histomorphological patterns were observed on microscopy. The thyroid lesions were classified into Neoplastic and Non-neoplastic based on histomorphological features and the data was segregated according to this and analysed. There was a total of 194 specimens, of which 175 were from female and 19 were from male patients. Maximum number of thyroid lesions were seen in the age group of 30–50 years. Among 194 patients, 52 (26.8%) were found to have neoplastic lesions, of whom, 25 (12.8%) patients had benign and 27(14%) patients had malignant lesion. 141(72.7%) patients had non neoplastic conditions. One patient had lymphoproliferative disorder (0.5%). In Neoplastic lesions, Among Benign lesions, Follicular adenoma was found be present in 25 patients. In malignant lesions, Papillary carcinoma was the most commonly found lesion (25 cases, 12.9%). 141(73%) patients had Non neoplastic conditions. Most commonly occurring Non neoplastic lesions were Nodular goiter (50 cases, 25.8%) followed by Colloid goiter (34cases, 17.5%), Multinodular goiter (33 cases, 17%), Hashimoto’s thyroiditis (5 cases, 2.6%). Followed by Chronic lymphocytic thyroiditis (4 cases, 2.1%). The frequency of carcinoma is more common in females amongst the total thyroid lesions. Papillary carcinoma was the most frequent malignancy (12.9%) among the thyroidectomy specimens. Papillary carcinoma was the commonest malignant lesion with female preponderance whereas, nodular goiter and colloid goiter were the commonest non neoplastic lesions with female preponderance.

Introduction

Thyroid gland is one of the important endocrine organs with significant role in physiology of body. The thyroid hormones affect all body organs and are responsible for maintenance of body integrity and hemostasis [10]. Thyroid disorders are being increasingly diagnosed with greater awareness and is one of the chronic non-communicable diseases affecting women more than men. Among all endocrine disorders, thyroid disorders are the most common in India [11].

It is the largest gland of all endocrine organs which plays vital physiological role in the body which can be affected by a variety of diseases ranging from functional, immunologically mediated enlargements, to neoplastic conditions [12, 13]. Thyroid gland lesions vary in incidence in relation to age, sex, geographical area dietary and environmental factors [14].

Most of the thyroid swellings are benign while 10–20% of the thyroid swellings are malignant [13]. Histological classification of thyroid lesions especially neoplastic conditions is essential for further treatment and prognosis [15].

Diagnosis of a thyroid disease includes a thorough history, clinical examination with assessment of the hormone secretion activities of the gland and its morphology [16]. Routinely, various modalities like USG neck, thyroid scan, thyroid function tests, FNAC and histopathology are used for evaluation of thyroid nodules. In those investigations FNAC is inexpensive, sensitive and accurate procedure for dividing patients into operative and non-operative category but histopathology of thyroidectomy specimen is gold standard as it gives a definitive diagnosis in surgically removed thyroid [17, 18].

Indications for thyroidectomy include: patients with symptomatic goiters e.g., with pressure symptom, or cosmetic problem.

Methodology

Source of data

Patients of either sex who underwent thyroidectomy in two tertiary care hospitals, Chigateri district hospital and Bapuji hospital, teaching hospitals attached to J.J.M. Medical College, Davanagere, were selected for the study and biopsy specimen were examined and analysed by Pathology department in JJM Medical college.

Study of Design

Retrospective study.

Study Duration

January 2021 to January 2023.

Sample Size ( 1.5.6)

Sample size calculation was done based on the previous studies. In one of the Indian studies, Thyroidectomy specimens were observed retrospectively and found that the most common thyroid disorders were non-neoplastic lesions (82%). Considering 82% Prevalence of Non-neoplastic lesions with 6% margin of error minimum sample needed to conduct this study was found to be 158 cases.

Sample Size =	Zα2	P (1-P)
		d2
Zα2 = Std normal variate 1.96
P = Expected proportion from population
d = Absolute error

The study material consists of total of 194 thyroidectomy specimens that encompass lobectomy, nodule excision, hemithyroidectomy, subtotal thyroidectomy, and total thyroidectomy specimens received from the Departments of General Surgery and Ear, Nose, and Throat (ENT).

After pathological diagnosis, the data and final report were systematically entered into the register and system. The biopsy registers were reviewed and different lesions were categorized. Age and sex-wise variations of the lesions were noted. And statistical analysis was done and following results were found.

Inclusion Criteria

1. Patients who underwent thyroidectomy surgery from January 2021 to January 2023 were included in the study.

Results

A total of 194 thyroidectomies were performed during the 2 years study period.

The surgeries include Nodule excision, Hemithyroidectomy, Total thyroidectomy.

Amongst the total specimens examined, 175 (90.2%) specimens were from females and 19 (9.8%) from males with a ratio of 9.2:1. (Table 1)

Table 1.

sex distribution

Gender	No of Cases	Percent	Ratio
Male	19	9.8	9.2 : 1
Female	175	90.2
Total	194	100.0

Inference- There were 175 (90.2%) females and 19 (9.8%) males with the ratio of 9.2:1

Maximum number of thyroid lesions were seen in the age group 30–39 years, consisting of 63 patients (32.5%), followed by 40–49 years, around 48 patients (24%) and 20–29 years, about 44 patients (22.7%). Minimum number was seen in age group of 10–19 years of age (3.1%) and > 60years (5.7%). (Table 2)

Table 2.

Age distribution

Age	No of Cases	Percent
10–19	6	3.1
20–29	44	22.7
30–39	63	32.5
40–49	48	24.7
50–59	22	11.3
≥ 60	11	5.7
Total	194	100.0

Inference- Maximum number of thyroid lesions were seen in the age group 30–39 years 63 cases, (32.5%), followed by 40–49 years around 48 cases(24%) and 20–29 years 44 cases(22.7%). Minimum number was seen in age group of 10–19 years of age (3.1%) and > 60years (5.7%) of cases

Among 194 patients, 52 (26.8%) were found to have neoplastic lesions, of whom, 25 (12.8%) patients had benign and 27(14%) patients had malignant lesion. 141(72.7%) patients had non neoplastic conditions. One patient had lymphoproliferative disorder (0.5%).

In Neoplastic lesions, Among Benign lesions, Follicular adenoma was found be present in 25 patients.

In malignant lesions, Papillary carcinoma was the most commonly found lesion (25 cases, 12.9%).

Most commonly occurring Non neoplastic lesions were Nodular goiter (50 cases, 25.8%) followed by Colloid goiter (34cases, 17.5%), Multinodular goiter (33 cases, 17%), Hashimoto’s thyroiditis (5 cases, 2.6%). Followed by Chronic lymphocytic thyroiditis (4 cases, 2.1%). Table 3. graph 1.

Table 3.

Neoplastic vs. Non neoplastic lesions

Diagnosis	No of Cases	%
Neoplastic
Benign
Follicular adenoma	25	12.9
Malignant
Follicular carcinoma	2	1
Papillary carcinoma	25	12.9
Non neoplastic
Adenomatous nodule	15	7.7
Colloid goiter	34	17.5
MNG	33	17
Nodular goiter	50	25.8
Chronic lymphocytic thyroiditis	4	2.1
Hashimotos thyroiditis	5	2.6
Other
Lymphoproliferative disorders	1	0.5
Total	194	100

Inference - Among 194 patients, 52 (26.8%) were found to have neoplastic lesions, of whom, 25 (12.8%) patients had benign and 27(14%) patients had malignant lesion. 141(72.7%) patients had non neoplastic conditions. One patient had lymphoproliferative disorder (0.5%)

In Neoplastic lesions, Among Benign lesions, Follicular adenoma was found be present in 25 patients

In malignant lesions, Papillary carcinoma was the most commonly found lesion (25 cases, 12.9%)

Most commonly occurring Non neoplastic lesions were Nodular goiter (50 cases, 25.8%) followed by Colloid goiter (34cases, 17.5%), Multinodular goiter (33 cases, 17%), Hashimoto’s thyroiditis (5 cases, 2.6%). Followed by Chronic lymphocytic thyroiditis (4 cases, 2.1%)

Graph 1.

Neoplastic Vs Non neoplastic lesions. Inference - Among 194 patients, 52 (26.8%) were found to have neoplastic lesions, of whom, 25 (12.8%) patients had benign and 27(14%) patients had malignant lesion. 141(72.7%) patients had non neoplastic conditions. One patient had lymphoproliferative disorder (0.5%). In Neoplastic lesions, Among Benign lesions, Follicular adenoma was found be present in 25 patients. In malignant lesions, Papillary carcinoma was the most commonly found lesion (25 cases, 12.9%). Most commonly occurring Non neoplastic lesions were Nodular goiter (50 cases, 25.8%) followed by Colloid goiter (34cases, 17.5%), Multinodular goiter (33 cases, 17%), Hashimoto’s thyroiditis (5 cases, 2.6%). Followed by Chronic lymphocytic thyroiditis (4 cases, 2.1%).

Among 18 thyroidectomy specimens in male sex, 11 were Non neoplastic (8%) and 7 were Neoplastic (13.5%).

Out of 175 thyroidectomy specimens in females, 130 were Non neoplastic (92%) followed by 45 Neoplastic lesions (86.5%).

Table 4 graph 2.

Table 4.

Incidence of lesion

Gender	Non neoplastic		Neoplastic		Total
	Count	%	Count	%	Count	%
Male	11	8	7	13.5	18	9.3
Female	130	92	45	86.5	175	90.7
Total	141	100	53	100	194	100.0

Inference - Among 18 thyroidectomy specimens in male sex, 11 were Non neoplastic (8%) and 7 were Neoplastic (13.5%)

Out of 175 thyroidectomy specimens in females, 130 were Non neoplastic (92%) followed by 45 Neoplastic lesions (86.5%)

Graph 2.

Incidence of lesions. Inference - Among 18 thyroidectomy specimens in male sex, 11 were Non neoplastic (8%) and 7 were Neoplastic (13.5%). Out of 175 thyroidectomy specimens in females, 130 were Non neoplastic (92%) followed by 45 Neoplastic lesions (86.5%).

Discussion

According to WHO, 7% of the world population is suffering from clinically apparent goiter.

Thyroid enlargement may be in the form of multinodular, solitary nodule or diffuse goiter.[16] Thyroid diseases are generally more prevalent in females [19]. Benign neoplasms out number thyroid carcinomas by a ratio of nearly 10:1 [20].

Sreedevi A R et al [1]. performed a record based retrospective study, conducted in a tertiary care teaching centre over a period of 2 years, from November 2014 to October 2016. 620 thyroidectomy specimens were observed. Amongst them, most common thyroid disorders were found to be non-neoplastic lesions, constituting 82% of lesions and neoplastic lesions constituting 18%, with female preponderance. Most common age group is 40–50 years. In accordance with this study, in our study there was female preponderance with most commonly found lesions being benign lesions.

Sadia alam et al [2]. conducted a 5 years study from 2012 to 2017 and included 67 patients showing varied patterns of histomorphological spectrum of surgical specimens of thyroid with a most frequent lesion being multinodular goiter. Non- neoplastic cases were (86%) and neoplastic cases were (13%). Follicular adenoma was the commonest benign lesion, while most frequent thyroid carcinoma was found to be papillary variant. Similarly, in our study, we found that colloid goiter was the most common benign and papillary carcinoma was the most common malignant lesion.

Haque WS et al [3]. performed a retrospective study from 1st January 2018 to 30th June 2019. Study included 377 specimens. Prevalent form of thyroid diseases was found to be nodular goiter that mostly affected females. Papillary carcinoma was the commonest malignancy of thyroid gland and was seen to predominantly affect females. In our study, we also found colloid goiter and nodular goiter to be the most common benign lesions and papillary carcinoma was the most common malignant lesion.

Elizabeth Joseph et al [4]. conducted a 6 years retrospective study (January 2010 to December 2015), of around 801 patients, between age group of 41 to 50 years. It showed that Multinodular goiter was the most common thyroid lesion in the study. The percentage of malignant thyroid tumours was high compared to other studies. Papillary carcinoma was the most common malignant neoplasm. The micropapillary variant comprised 50% of the papillary carcinoma. In our study we found that benign lesions were most common compared to malignant lesions.

Rahman MA et al [5]. conducted a histomorphological evaluation of thyroid lesions in relation to age and sex of the patients, which included 108 thyroidectomy specimens from January 2006 to June 2012. The study found that non neoplastic lesions were more common, like, colloid goiter, including diffuse and nodular goiter around 92.05%. Papillary carcinoma was the commonest malignant lesion followed by follicular carcinoma and anaplastic carcinoma. In our study we found papillary carcinoma of thyroid was the most commonly found lesion in both male and female sex.

Ambreen Beigh et al [6]. showed that Thyroid cancer was a relatively rare malignancy, but it was the commonest endocrine cancer accounting for 92% of all endocrine malignancies. It is both retrospective and prospective study done over a period of five years from January 2013 to February 2018 and included 282 thyroid patients. It reported that Papillary carcinoma was the commonest malignant lesion while as follicular adenoma was the commonest benign lesion. In accordance to this, in our study, papillary carcinoma was the most common malignant lesion.

Dilasma Ghartimagar et al [7]. conducted a descriptive cross-sectional study at Manipal Teaching Hospital, from Jan 2005 to Jan 2020, involving 345 thyroidectomy specimens. It showed Colloid goiter and papillary carcinoma was the most commonly encountered non-neoplastic and neoplastic lesion respectively, with a female predominance. Rare tumours like anaplastic carcinoma, papillary carcinoma, and follicular carcinoma with anaplastic transformation were also encountered. Similar to this study, in our study also we found female preponderance in both benign and malignant lesions.

Abdulla H. Darwish et al [8]. conducted a study from January 2000 to December 2004, 110 cases of thyroidectomy specimens were examined. Thyroid malignancy accounted for 24% of patients with thyroid swelling who underwent surgery.

V Taşova et al [9]. showed a study of 443 patients, including those with benign multinodular goitre (BMNG) or toxic adenoma or toxic multinodular goitre. Papillary cancer was also the most common type of thyroid cancer between genders. As compared to gender, there was no statistically significant difference found in this study. In our study we found out nodular goiter is the most common benign lesion followed by colloid and multinodular goiter.

Conclusion

Among Non neoplastic conditions in 141(73%) patients, Most commonly occurring Non neoplastic lesions were Nodular goiter (50 cases, 25.8%) followed by Colloid goiter (34cases, 17.5%), Multinodular goiter (33 cases, 17%), Hashimoto’s thyroiditis (5 cases, 2.6%). Followed by Chronic lymphocytic thyroiditis (4 cases, 2.1%). In Neoplastic lesions, Benign lesions, Follicular adenoma was found be present in 25 patients. In Malignant lesions, Papillary carcinoma was the most commonly found lesion (25 cases, 12.9%). With most common preponderance in female population as compared to male. This study gains significance in concluding the histomorphological pattern in developing countries.

Limitations

As, this is a single tertiary care hospital based study, this may not necessarily represent the entire population.

Funding

The authors have no relevant financial or non-financial interest to disclose.

Data Availability

The data used in this study was not used/published in any other publications.

Code Availability

IBM SPSS Version 22 for windows will be used for analysing the data.

Declarations

Conflict of Interest

The Authors declare that there is no conflict of interest.

Consent for Publication

All authors have reviewed the manuscript and approved the version to be published.

Ethics Approval

The study was done after approval of the Institutional Ethics committee from JJM Medical College, Davangere, Karnataka, India in accordance with ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

Consent to Participate

Written informed consent was taken from all the patients.