Salivary gland lesions encompass a wide range of non-neoplastic and neoplastic entities with diverse histomorphological features. Accurate preoperative diagnosis is crucial for planning the appropriate surgical approach and management. Fine Needle Aspiration Cytology (FNAC) has become the preferred initial diagnostic procedure for evaluating salivary gland swellings due to its simplicity, minimal invasiveness, and rapid turnaround time¹.

However, diagnostic terminology and reporting criteria have historically varied across institutions, resulting in inconsistent interpretations and reporting². To address this, the Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) was introduced, providing a standardized reporting structure with defined diagnostic categories and associated risk of malignancy (ROM).

This study aims to evaluate the cytomorphological features of salivary gland lesions according to the MSRSGC, and to correlate cytological diagnoses with histopathological findings wherever available

Study Design and Duration

A prospective observational study was conducted in the Cytopathology and Histopathology Laboratory, Department of Pathology, P.D.U Medical College and Hospital, Rajkot, Gujarat over a period of one year, involving 94 patients presenting with salivary gland swellings. All the cases referred to the department of Pathology from the Department of Surgery, ENT, and Dental Surgery for evaluation of salivary gland lesions were included in the study.

Procedure

FNAC was performed using a 22–24 gauge needle, with 10 mL syringe. Both air-dried and alcohol-fixed smears were prepared and stained using:

• Hematoxylin and Eosin (H&E)
• May-Grünwald Giemsa (MGG)
• Papanicolaou (PAP)

Categorization

Each case was classified according to the Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) into one of the following categories:

1. Category I: Non-diagnostic / Unsatisfactory
2. Category II: Non-neoplastic
3. Category III: Atypia of undetermined significance (AUS)
4. Category IVa: Benign neoplasm
5. Category IVb: Salivary gland neoplasm of uncertain malignant potential (SUMP)
6. Category V: Suspicious for malignancy
7. Category VI: Malignant

Histopathological Correlation

Surgical excision or biopsy specimens were available for 36 cases, which were compared with their corresponding cytological diagnosis to determine diagnostic accuracy.

Statistical Analysis

Sensitivity, specificity, and diagnostic accuracy were calculated using standard formulas

Distribution of cases according to sex, age, and site of involvement of the lesion.

Table 1: - SEX DISTRIBUTION OF PATIENTS

A male predominance was observed (male-to-female ratio 1.8:1), consistent with previous studies⁴⁻⁶.

Table 2: - AGE WISE DISTRIBUTION OF SALIVARY GLAND LESION

In our study we had male predominance and most of the cases were seen in the age group of 21-35 years.

Table 3: - SITE DISTRIBUTION OF SALIVARY GLAND LESION

Patients had presented with lesions in all the major and minor salivary glands-parotid, submandibular and sublingual. The parotid gland was the most commonly affected site, aligning with findings in prior studies⁷⁻⁹.

Table 4: - CYTOLOGICAL EVALUTION WAS DONE ACCORDING TO THE MILAN SYSTEM.

Overall, 26 (27%) cases were non-neoplastic, and 68 (73%) were neoplastic. Pleomorphic adenoma was the most common lesion, followed by Warthin’s tumor.

Histopathological Correlation (n = 36)

Out of the 36 cases available for histopathology:

The findings of this study reaffirm that FNAC is a highly specific, minimally invasive, and cost-effective diagnostic tool for evaluating salivary gland lesions¹⁰⁻¹². The age and site distribution pattern observed aligns with previous studies, showing a predominance of parotid involvement and peak incidence in young to middle-aged adults.

The distribution of lesions in this study parallels prior research, with parotid involvement being the most common and pleomorphic adenoma the predominant benign tumor⁴,⁶,⁸. The observed sensitivity (75%) and specificity (100%) correspond with results reported by Manju et al., Sheetal et al., and Yogambal et al.¹³⁻¹⁵. Although certain low-grade or cystic malignancies may yield false-negative results, false positives are rare, confirming FNAC’s reliability for surgical decision-making.

The Milan System standardizes salivary gland cytology reporting and bridges the diagnostic gap between cytopathologists and clinicians³,¹⁶. Its category-wise ROM assists in management planning, as summarized below:

• Category II: Conservative management
• Category IVa: Simple excision
• Category VI: Radical surgery or oncological therapy

Overall, the present findings closely align with previous Indian and international studies, demonstrating the effectiveness of MSRSGC in routine reporting and its clinical utility in guiding management.

Comparison of Risk of Malignancy (ROM) with Other Studies

The ROM values in the present study are largely consistent with the established Milan System benchmarks. The slightly lower ROM in the SUMP and Suspicious for malignancy categories may be attributed to the smaller number of histologically correlated cases.

FNAC of salivary gland lesions, when interpreted using the Milan System for Reporting Salivary Gland Cytopathology, is an effective and reliable diagnostic modality with high specificity and good sensitivity.
The system enhances diagnostic clarity, risk stratification, and clinical decision-making. Histopathological correlation further validates the diagnostic reliability of FNAC, especially in differentiating benign from malignant lesions

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