Paraneoplastic multisystem autoimmune syndrome associated with renal adenocarcinoma

Abstract

Preneoplastic autoimmune multisystemic syndrome is a rare entity in which systemic autoimmune disorders present as preneoplastic manifestations of malignant tumors. We report the case of a 62-year-old male adult with skin lesions and urinary tract abnormalities of several years of evolution, who was diagnosed with left kidney adenocarcinoma. Initially, he received symptomatic treatment without significant improvement. Given the persistence of symptoms and the appearance of systemic signs, a comprehensive evaluation was performed, including skin biopsies, immunological studies, and imaging tests. The results led to the finding of a kidney adenocarcinoma as the probable origin of the clinical picture. The patient underwent radical nephrectomy, after which a 90% remission of skin lesions and a significant improvement in urinary symptoms were observed, suggesting a preneoplastic mechanism in the genesis of the autoimmune multisystemic syndrome. Subsequent follow-up confirmed the absence of tumor recurrence and sustained recovery from autoimmune manifestations. Preneoplastic autoimmune multisystemic syndrome is a rare entity, as it may go unnoticed due to low clinical suspicion. Treatment includes topical and systemic therapy for skin lesions, as well as left radical nephrectomy to resolve the renal adenocarcinoma and, consequently, the resolution of skin lesions. This case highlights the importance of considering preneoplastic autoimmune manifestations in the evaluation of patients with dermatologic and systemic symptoms without an apparent cause.