# Scalp Involvement in Primary Cutaneous Lymphomas—An Update on Clinical Presentation, Diagnostics, and Management

## TL;DR

This paper reviews how primary cutaneous lymphomas affect the scalp, focusing on their clinical features, diagnosis, and treatment.

## Contribution

The study provides an updated analysis of scalp involvement in primary cutaneous lymphomas, highlighting diagnostic and clinical patterns.

## Key findings

- Primary cutaneous follicle center lymphoma is the most common B-cell lymphoma on the scalp.
- Mycosis fungoides is the most frequent T-cell lymphoma affecting the scalp.
- Alopecia was observed in 69% of patients with scalp lymphomas.

## Abstract

Primary cutaneous lymphomas are a group of rare diseases. It is uncommon for these diseases to affect the scalp. The goal of this study was to understand how this disease looks, how it is diagnosed, and how it is treated in patients with primary cutaneous lymphoma of the scalp. A thorough review of the existing literature was performed using the PubMed database. The search terms included “scalp” and “cutaneous lymphoma”, “folliculotropic mycosis fungoides” and “scalp”, “trichoscopy” and “lymphoma”, and “dermoscopy” and “scalp” and “lymphoma.” The research found 1482 patients with skin problems caused by primary cutaneous lymphoma. Of the total number of cases, 1096 were diagnosed with B-cell primary cutaneous lymphoma, 384 with T-cell primary cutaneous lymphoma, and two cases lacked a precise diagnosis. Primary cutaneous follicle center lymphoma was the most commonly reported type of B-cell lymphoma on the scalp, while mycosis fungoides was the most common type of T-cell lymphoma. Hair loss was seen in 69.0% of the patients in this study. Some lymphomas affecting the scalp are more aggressive. Therefore, it is important to remember that primary cutaneous lymphomas may affect this area.

Primary cutaneous lymphomas (PCLs) constitute a heterogeneous group of rare diseases. Previously, few studies have focused on the aspect of scalp involvement by PCLs. The objective of this study was to analyze the clinical presentation, diagnostic pathways, and treatment methods in patients diagnosed with scalp PCLs. A comprehensive literature review was conducted using the PubMed database, with the search terms “scalp” AND “cutaneous lymphoma”, “folliculotropic mycosis fungoides” AND “scalp”, “trichoscopy” AND “lymphoma”, and “dermoscopy” AND “scalp” AND “lymphoma.” The search was limited to articles published from database inception to May 2, 2024. Based on the title and abstract analysis, we included articles on PCLs involving the scalp. After a thorough review of the full manuscripts, several were excluded due to irrelevance, the absence of essential clinical data, discrepancies in patient age, gender, and diagnosis, and a lack of information pertinent to scalp PCLs. The literature search identified 1482 patients with scalp involvement in PCLs. Of the total number of cases, 1096 were diagnosed with B-cell PCLs, 384 with T-cell PCLs, and two cases lacked a precise PCL diagnosis. Primary cutaneous follicle center lymphoma was the most frequently reported B-cell PCL of the scalp, while mycosis fungoides was the most common T-cell PCL. Alopecia was observed in 69.0% of the patients analyzed, with the most prevalent form being non-scarring focal alopecia. It is imperative to consider the scalp in patients with PCLs, particularly in light of the knowledge that some lymphomas affecting the scalp exhibit a higher degree of aggressiveness.