Resolution of Bullous Pemphigoid Following Lung Cancer Resection: A Case of Paraneoplastic Pemphigoid.

Bullous pemphigoid (BP) is a chronic autoimmune disorder characterized by subepidermal blister formation, primarily affecting elderly individuals. While BP has been associated with malignancies, the exact nature of this relationship remains unclear. We report the case of a 72-year-old man who presented with pruritic cutaneous lesions, including tense vesicles and bullae and was diagnosed with BP. Despite treatment with doxycycline, nicotinamide, and topical clobetasol, his symptoms persisted. A routine chest X-ray, conducted as part of his diagnostic workup, incidentally, revealed a large mass in the right upper lung, which was subsequently diagnosed as squamous cell carcinoma. Remarkably, after the surgical resection of the tumor, the patient's BP lesions completely resolved within seven weeks, without alterations to his dermatologic treatment. This case emphasizes the importance of malignancy screening in patients with persistent BP and suggests a possible link between BP and underlying cancer, particularly when standard therapies prove ineffective. Further investigation into the mechanisms connecting these conditions is warranted.