Clinicopathological Profile of Cutaneous Lymphoma and Distinction of Early Mycosis Fungoides from Cutaneous Lymphoid Hyperplasia—A Retrospective Experience from Quaternary Care Centre in South India

Introduction: Cutaneous lymphomas represent the second most common extra-nodal non-Hodgkin lymphoma. Mycosis fungoides (MF) is the most common primary cutaneous lymphoma. In this study, we aim to estimate the prevalence of cutaneous lymphomas and to differentiate early MF from reactive cutaneous lymphoid hyperplasia (CLH) of the skin. Materials and Methods: We retrospectively studied all biopsy and resection specimens with a high index of clinical and histomorphological suspicion for cutaneous lymphoma for 10 years. We classified all the cases according to the World Health Organisation’s (WHO) 2022 classification of haematopoietic and lymphoid neoplasms. Statistical analyses were carried out using the software SPSS Statistics v23.0. Results: Out of 33 lymphoma cases, MF was the most common, followed by subcutaneous panniculitis-like T-cell lymphoma (SPLTCL). There were 13 males (39.3%) and 20 females (60.7%). Patches were the most common skin lesion, accounting for 78.7% of the cases, and presented as multiple lesions (81.8%), with the majority affecting the extremities (33.3%). Epidermotropism and basal tagging of lymphocytes, dermal fibrosis, and convoluted nuclear membranes were significant in early MF. Spongiosis correlated negatively with MF. T-cell receptor rearrangements were observed in 12 cases of MF. Conclusion: MF, the most common cutaneous lymphoma, is increasingly common in younger people. Histological variables such as epidermotropism, basal tagging of lymphocytes, convoluted nuclear membranes, and dermal fibrosis, along with clonal T-cell receptor rearrangements, aid in correct diagnosis and early therapeutic decision-making.