ABSTRACT
BACKGROUND: Granuloma annulare (GA) is a granulomatous skin eruption rarely associated with cancer. We report seven cases of paraneoplastic GA in association with solid organ malignancy. OBJECTIVE: To compare the clinical and histopathological features of paraneoplastic GA to case-matched controls of classic GA. METHODS: Retrospective chart and histopathological review of 7 individuals and 13 age- and sex-matched controls. Paraneoplastic GA was defined as GA occurring within 6 months of the diagnosis of solid organ malignancy and/or persistent GA that resolved with cancer treatment. RESULTS: Most cases of paraneoplastic GA were associated with lung cancer (4/7). The clinical and histopathological features of paraneoplastic and classic GA were similar. Compared to classic GA, paraneoplastic GA cases were more often generalized disease (6/7 vs 6/13), refractory to treatment, and had a perivascular inflammatory cell infiltrate (5/7 vs 2/13). All cases of paraneoplastic GA that underwent definitive treatment of their cancer improved. LIMITATIONS: Single-institution, retrospective review with a small sample size. CONCLUSION: Paraneoplastic GA is rare, similar to classic GA, and refractory to treatment. We advocate for age-appropriate screening in individuals with GA that is nonresponsive to multiple lines of systemic treatment and evaluating patients with concerning signs or symptoms for an underlying neoplasm.
Subject(s)
Cell Transformation, Neoplastic/pathology , Granuloma Annulare/epidemiology , Granuloma Annulare/pathology , Lung Neoplasms/epidemiology , Paraneoplastic Syndromes/pathology , Aged , Brain Neoplasms/epidemiology , Brain Neoplasms/pathology , Breast Neoplasms/epidemiology , Breast Neoplasms/pathology , Case-Control Studies , Female , Glioblastoma/epidemiology , Glioblastoma/pathology , Glioblastoma/therapy , Humans , Incidence , Lung Neoplasms/pathology , Male , Melanoma/epidemiology , Melanoma/pathology , Melanoma/therapy , Middle Aged , Paraneoplastic Syndromes/epidemiology , Prognosis , Risk Assessment , Skin Neoplasms/epidemiology , Skin Neoplasms/pathology , Treatment OutcomeABSTRACT
Despite well-defined clinical and histopathological features of melanoma, atypical presentations mimicking other skin disorders can result in a delayed diagnosis or misdiagnosis and subsequent inappropriate treatment. Rosai-Dorfman disease (RDD) is a rare histiocytic disorder with unique clinical and histopathological features. We report a case of melanoma treated with cryotherapy that mimicked RDD both clinically and histopathologically. We compare this RDD-like melanoma to classic RDD, outlining the importance of clinicopathological correlation prior to treatment, as well as the potential pitfalls in diagnosis after cryotherapy of pigmented lesions.
