Cutaneous amyloidosis mimicking basal cell carcinoma: a case series and literature review

Amyloidosis is characterized by extracellular amyloid protein deposition. When amyloidosis intersects with basal cell carcinoma (BCC), it introduces complex diagnostic challenges. This study explored the overlap between primary localized cutaneous amyloidosis (PLCA) and BCC, examining amyloid deposits in BCC, systemic amyloidosis risk in PLCA, and various treatment methods.

Two case studies were discussed, followed by a literature review, in which PubMed, Web of Science, EMBASE, and the Cochrane Library databases were utilized. The search, covering studies from infinity up to January 2024, focused on "cutaneous amyloidosis," "basal cell carcinoma," and related terms. Articles in English detailing the clinical presentation, diagnostic methods, treatment, and outcomes of cutaneous amyloidosis mimicking BCC were included. Data extraction and synthesis were performed by two independent reviewers.

This study highlighted two cases exemplifying the complexity of diagnosing BCC and PLCA. The first case (a 64-year-old with a nodule on the cheek) and the second (a 67-year-old with a nodular lesion on the upper lip cheek) were initially suspected as BCC and were later identified as PLCA upon histopathological examination.

The diagnosis of amyloidosis within BCC nodules remains a diagnostic challenge. Although their coexistence is relatively prevalent, their local recurrence rates remain debatable. Various diagnostic and therapeutic approaches have been suggested, such as topical creams and phototherapy. However, none have garnered conclusive and consistent evidence to establish reliable clinical application.

The findings emphasized the importance of considering alternative pathologies in differential diagnoses. Future research should focus on understanding systemic amyloidosis risks and optimizing care for both conditions.