Abstract

Primary cutaneous CD30-positive lymphoproliferative disorders are the second most common type of primary cutaneous T-cell lymphomas (CTCL) after mycosis fungoides (MF), accounting for approximately 30% of cases. This group of CTCL mainly includes a spectrum of entities that have lymphomatoid papulosis (LyP) at one side and primary cutaneous anaplastic large-cell lymphoma (PC-ALCL) at the other. Clinical presentation and follow-up are important; since the histopathological diagnosis is usually insufficient to distinguish between two lesions, especially in borderline cases which have the features of both. A 67-year-old male patient with a previous history of melanoma and basal cell carcinoma, presented with a dusky, red, and itchy papule on the wrist, which had been there for the past 2 weeks. The patient reported that he may have been bitten by a spider while on a trip to Arizona. A punch biopsy is performed with the differential diagnoses of arthropod assault and neutrophilic dermatosis. The biopsy of the lesion showed diffuse large atypical CD30+ lymphocytes with periadnexal and perivascular involvement. The patient is scheduled for further tests including a PET scan and clinical follow-up. Primary cutaneous CD30+ lymphoproliferative diseases demonstrate a wide spectrum of clinical and histopathological features. The patients should be followed up clinically in order to establish a definitive diagnosis and appropriate management. Furthermore, patients should be referred for further work-up in order not to miss systemic ALCL with extranodal cutaneous involvement. We report this case to underscore the importance of both clinicopathological and radiographic correlation in CD30-positive lymphoproliferative cases.