Thyroid nodules are common clinical findings. Fine-needle aspiration (FNA) of the thyroid gland has proven to be an important and widely accepted, cost-effective, simple, safe, and accurate method of triaging patients with thyroid nodules.

“The Bethesda System for Reporting Thyroid Cytopathology” (TBSRTC) provides standardization definitions, diagnostic/morphologic criteria, explanatory notes, and a concise management plan for each diagnostic category.

Aims and objectives:

To study the cytomorphology of thyroid lesions and classify them as per TBSRTC. Determine the distribution of various thyroid lesions in our tertiary care hospital. Correlation of cytopathology with histopathological diagnosis.

Type of study: Prospective Study (Study of total 110 cases).

Duration of Study: 6 months (February 2024 to July 2024) in the Department of Pathology, P.D.U medical college and civil hospital, Rajkot.

Inclusion criteria: All patients with thyroid lesions, regardless of age or gender, who were admitted to wards or referred from the ENT and Surgery OPD to the Department of Pathology at PDU medical college Rajkot. Cytological examinations were included.

Exclusion criteria:

Patients who are unwilling participate.

Patients with hypothyroidism.

Informed consent was obtained from the patients.

Thyroid swellings were aspirated using (23/24) gauge disposable needles using standard procedures. The aspirated contents of the needle were expelled onto glass slides. Four slide smears were made for each case and immediately fixed in 95% ethyl alcohol for about 30 min. All the slides were stained with Hematoxylin and eosin stain. Diagnosis of cytological smears was done according to standard criteria.

We categorized our results into insufficient for diagnosis, benign, atypical follicular lesion of undetermined significance, follicular neoplasm, suspicious for malignancy, and malignant sampling according to the recent Bethesda classification [8]. Aspirates with insufficient cellularity or poor-quality smear due to delayed or inadequate fixation or aspirate containing cyst fluid were considered ‘‘unsatisfactory’’. FNAC results were then compared with the definitive histological diagnosis in our study histopathological diagnosis of 30 cases available.

Table I: shows age group wise distribution (n=110).

Table II: Shows Gender wise distribution of thyroid lesion

Table III: Shows categorization of cytopathological diagnosis according to Bethesda system (n=110)

Table IV: Shows cytomorphological and Histopathological correlation of thyroid lesions (n=110)

As shown in table, Out of 21 cases available from cat II, 19 cases are benign and 2 cases were malignant, 05 cases from cat III, 03 cases are benign and 02 cases were malignant, 01 case from cat IV and 01 case from cat V was malignant, cat IV( Follicular carcinoma), cat V(Papillary carcinoma of thyroid).

The use of FNAC is justified owing to the procedure being inexpensive, minimally invasive, with minimal complications, and for giving an early preoperative diagnosis for most of the thyroid lesions.  Comparative study of our study's age distribution with other studies. In our study, the age of patients ranged from 10 to 80 years with most of patients from 31-40 years. Similar age was seen in other studies by Naz et al. [2], Gupta et al. [3], Bhat et al. [4], Dhamecha et al. [5] , and Khatib et al. [6]. Thyroid lesions are more prevalent in females, in our study, the female to male ratio was 6.3:1 Similar ratio was seen in studies by Melo-Uribe et al. [7] (7.9:1) and Handa et al. [8] (5.3:1).  In the present study, the percentage of cases in each category of TBSRTC was in accordance with the studies of Khatib et al. [6] and Mondal et al. [9].

The FNAC is an extremely useful, competent, and cost-effective method of investigation for thyroid lesions. Hence it can be used as a first line of pathological investigation which can help in identifying patients who will require non-invasive or invasive management.

The Bethesda system is very useful six-tiered standardized system of reporting thyroid cytopathology by decreasing the diagnostic discrepancies and facilitating diagnostic correlation with the histopathological excisions.

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