Histomorphological Spectrum and Diagnostic Challenges in Thymic Epithelial Neoplasms with their Prognostic Significance: A Case Series of 33 Cases at a Regional Cancer Center in Western India

 

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Abstract

Objective Pathological diagnosis of thymic epithelial neoplasms is challenging due to multiple subtypes, tumor heterogeneity, and variations in inter-observer reproducibility. Very few studies are available on their spectrum in the Indian subcontinent. In this study, we aimed to explore the morphological spectrum and diagnostic difficulties in the classification and subtyping of thymic epithelial neoplasms along with their prognostic significance in the Indian population.

Material and Methods Retrospectively, all surgically resected thymectomy specimens operated at our institute as well as outside review cases during the period were included. Histomorphology and immunohistochemistry (IHC) slides were reviewed and correlated with clinicopathological variables.

Statistical Analysis Microsoft Excel 2019 and SPSS version 20 were used for data analysis.

Results Among the 33 thymic epithelial neoplasms operated during the study period, the commonest subtype was thymoma B2 type followed by AB, B1, A, and B3 types. A single case each of micronodular thymoma, microscopic thymoma, and thymic carcinoma were identified. Six cases of thymomas with more than one pattern (other than ‘A’) were noted. The male:female ratio was 2:1. Stage I in Modified Masaoka staging and pT1a in TNM staging were most common. Seven cases had metastasis, four during initial presentation and three during subsequent follow-up.

Discussion and Conclusion Thymic epithelial neoplasms show morphological overlapping of features. Thorough sampling, morphology, and IHC for exact subtyping of thymoma and diligent search and documenting of lymphovascular invasion (LVI) are vital as both are separate risk factors for metastasis/recurrence and help the clinician in a better follow-up of patients.

Authors' Contributions

Design: Jahnavi Gandhi, Sonali Timaniya

Acquisition of Data: Karthik Dhandapani, Sonali Timaniya, Krutika Joshi

Analysis of Data: Jahnavi Gandhi, Sonali Timaniya, Karthik Dhandapani, Krutika Joshi

Drafting of manuscript: Jahnavi Gandhi, Sonali Timaniya, Karthik Dhandapani, Krutika Joshi

Critical Revision of Manuscript: Jahnavi Gandhi, Amisha Gami, Ashini Shah, Priti Trivedi

Statistical Analysis: Karthik Dhandapani

Technical Supervision: Jahnavi Gandhi, Amisha Gami, Ashini Shah, Priti Trivedi.

Availability of Data and Material

Available.

Ethics Approval

Waiver of consent.

Publication History

Article published online:
02 December 2022

© 2022. MedIntel Services Pvt Ltd. This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/)

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