Analysis of Granulomatous inflammatory lesions diagnosed on Cytology

Introduction

Granulomatous inflammation is defined in cytology as aggregates of epithelioid cells forming granuloma with or without necrosis and multinucleate giant cells.¹ Based on the aetiology, they are classified as non-infectious and infectious. Non-infectious causes are like sarcoidosis. Infectious conditions include tuberculosis, toxoplasma, cat scratch disease etc¹. Other way of classifying granuloma is based on morphology of granuloma such as classical, necrobiotic, foreign body, suppurative, naked, which is difficult on cytology.

FNAC of any palpable swelling is an excellent first line of investigation to determine the nature of the lesion. It is quick, safe and minimally invasive procedure. It involves aspirating cells and fluid with narrow bore needle followed by cytological examination. It is applicable to easily palpable superficial lesions such as tumors of skin and subcutis, thyroid, breast, salivary glands and lymph nodes. By using imaging techniques even, the aspirates from lung, abdominal and retroperitoneal organs can be obtained for cytological diagnosis.²

FNAC plays an important role in diagnosing granulomatous inflammatory lesions, thereby preventing unnecessary surgical intervention. The present study aims to analyse the data viz age, gender and site of granulomatous lesions diagnosed on cytology.

Material and methods

This is a retrospective study and data for the analysis was obtained from cytology records of Department of Pathology, at a tertiary care center.  All the FNAC samples with a cytological diagnosis of granulomatous inflammatory lesion diagnosed over a period of 2 years from January 2016 to December 2017 were included.  Relevant information related to age, gender and site of the lesion were retrieved from the records, tabulated and analyzed.

Results

Total number of cases diagnosed as granulomatous lesions on cytology during this period were 43. Age of the patients varied from 4 to 80 years with mean age of 41, Majority 55.8%(n=24) in 3rd and 4th ‘decade (21.40 years of age. ( Table 1)

Females were affected (67%) more than males, with a M:F of 1:2.1. Ziehl Neilson stain for demonstration of Acid fast bacilli was done in all the smears. Acid fast bacilli were demonstrated in only 5 (12%) aspirates. Lymph nodes of the neck constituted the major lesional site of aspiration(n=35). Two granulomatous lesions were from breast and one from thyroid.

Discussion

FNAC is a very valuable procedure for identifying diseases underlying any palpable mass as it is simple, safe, cost effective and time saving . Diagnosis of benign conditions by FNAC prevents unnecessary burden of surgeries on the patients. Granulomatous lesions can be easily diagnosed by the fine needle aspiration as it shows variable presence of characteristic aggregates of  epithelioid cells, giant cells and caseation necrosis.

In certain parts of the World, where tuberculosis is. endemic, fine needle aspiration of extrapulmonary sites such as lymph nodes forms a very useful and reliable test.

In the present study , Females were commonly affected (67%) which was in concordance with other studies.^1,3

Majority of the cases belonged to the age group of 21-50 years which was similar to studies done by Natraj et al4,’Rajaskaran et al⁵ and Purohit et al⁶

Cervical lymph nodes were the most common site of granulomatous lesions, similar to observation done by Hirchand et at⁷. Khajuria et al 8. and Chandwale et al¹.

Acid fast staining was performed on all the aspirations obtained from lymph nodes, but only 5 cases showed presence of acid-fast bacilli. AFB positivity on lymph node aspirates is variable. Reasons for the same being presence of very few organisms or patients on antitubercular treatment.

Granulomatous mastitis is an uncommon breast lesion which mimics carcinoma both clinically as well as radiologically. It may be associated with lactational change or postpartum period. Two cases of granulomatous mastitis were diagnosed in our study, in females and age 25 and 40 yrs. Majority of studies conducted show that granulomatous mastitis is common in reproductive age group^9,10.

One aspirate from chest wall showed structures resembling fungal hyphae and giant cells. All the granulomatous lesions were advised further investigation like histopathology for confirmation of cytological findings and other tests to confirm or rule out tuberculous infection.

Conclusion

From the study, it was found that, females were affected commonly. Granulomatous lesions affected 3rd and 4th decade. The most common organ involved was cervical group of lymph nodes.