Field cancerization: Treatment.

The goal of field cancerization treatment is to reduce the risk of developing keratinocyte carcinoma. Selecting the appropriate therapy depends on the degree of field cancerization and the number of invasive cutaneous squamous cell carcinomas. Other considerations include treatment efficacy, cost, side effects, and patient preference. Field therapies are preferred because they address clinically visible disease and subclinical atypia. However, lesion-directed therapies are useful for lesions that are more difficult to treat or those where a histologic diagnosis is required. Patients with extensive field cancerization benefit from a combination of field-directed and lesion-directed treatments. The second article in this continuing medical education series provides a framework to guide evidence-based decision making for field cancerization treatment.

Field cancerization: Definition, epidemiology, risk factors, and outcomes.

Field cancerization was first described in 1953 when pathologic atypia was identified in clinically normal tissue surrounding oropharyngeal carcinomas. The discovery of mutated fields surrounding primary tumors raised the question of whether the development of subsequent tumors within the field represented recurrences or additional primary tumors. Since this initial study, field cancerization has been applied to numerous other epithelial tissues, including the skin. Cutaneous field cancerization occurs in areas exposed to chronic ultraviolet radiation, which leads to clonal proliferations of p53-mutated fields and is characterized by multifocal actinic keratoses, squamous cell carcinomas in situ, and cutaneous squamous cell carcinomas. In the first article in this continuing medical education series, we define field cancerization, review the available grading systems, and discuss the epidemiology, risk factors, and outcomes associated with this disease.

Immune checkpoint inhibitors and the development of granulomatous reactions.

Immune checkpoint inhibitors (ICPIs) have emerged as a frontline treatment for a growing list of malignancies. Disruption of the negative regulatory immune checkpoints by ICPIs has been associated with many immune-related adverse events. Granulomatous reactions, such as sarcoidosis-like reactions, granulomatous panniculitis, granuloma annulare, and granulomatous dermatitis, are uncommon but increasingly recognized immune-related adverse events seen in patients treated with ICPIs. The frequency and significance of these eruptions, including whether they portend responsiveness to treatment, remain unclear. Additionally, understanding the role of immune checkpoint blockade in these reactions may provide mechanistic insight into the relevant signaling pathways involved in sarcoidosis and other granulomatous disorders.

Atypical manifestations of graft-versus-host disease.

BACKGROUND: Cutaneous graft-versus-host disease (GVHD) is classically described as morbilliform when acute and lichen planus-like or sclerotic when chronic. In addition to these well-known clinical forms, there are many other presentations of GVHD that are important to recognize. As the number of patients undergoing stem cell transplantation increases and the survival after transplantation improves, the prevalence of GVHD is expected to rise, and its various presentations will be increasingly encountered in clinical practice. OBJECTIVE: We sought to report unusual manifestations of skin GVHD and provide a summary of typical and atypical presentations of GVHD reported in the literature. METHODS: Patients with stem cell transplantation who developed unusual eruptions after transplantation had biopsy specimens taken to evaluate for histopathologic evidence of GVHD. RESULTS: Six patients presented with unusual cases of biopsy-proven GVHD, including follicular hyperkeratosis, thick-appearing white tongue, inverse pityriasis rosea-like, and eczema craquelé-like GVHD. LIMITATIONS: This study is limited by case number. CONCLUSIONS: Because of the high rate of cutaneous involvement with GVHD, the accessibility of the skin for diagnosis, and the morbidity associated with severe or long-standing skin involvement, it is important for dermatologists to recognize and accurately diagnose cutaneous GVHD in all its protean manifestations.

Low-dose radiotherapy for primary cutaneous anaplastic large-cell lymphoma while on low-dose methotrexate.

Primary cutaneous anaplastic large-cell lymphoma (pcALCL) is part of a spectrum of CD30+ primary cutaneous lymphoproliferative disorders (pcLPDs) that also includes lymphomatoid papulosis (LyP). Localized radiotherapy at doses of 34 to 44 Gy is first-line treatment of pcALCL, but the use of low-dose radiotherapy for pcALCL has not been reported. We present the case of a patient with a history of pcALCL/LyP who was treated with low-dose radiotherapy while on oral low-dose methotrexate (MTX) once weekly. This report suggests that low-dose radiotherapy can be an effective palliative treatment of pcALCL. Low-dose radiotherapy may offer certain advantages over traditional radiotherapy, such as a more economical and efficient treatment for patients, potentially fewer short-term and long-term side effects, and the potential for concomitant use with low-dose MTX.