Collision Tumor of the Kidney: Renal Cell Carcinoma Hidden in a Giant Angiomyolipoma in a Patient With Tuberous Sclerosis Complex.

Background: A renal angiomyolipoma is a mixed mesenchymal benign tumor composed of smooth muscle, adipose tissue, and blood vessels. Malignant transformation of angiomyolipomas is anecdotal. To our knowledge, only 6 cases have been reported, and 4 of the patients had tuberous sclerosis complex diagnosed. Case Report: We present the case of a 29-year-old male with tuberous sclerosis complex who arrived at the emergency room with gross hematuria and a painful right-sided abdominal mass. Imaging studies revealed active bleeding from a giant angiomyolipoma. An emergency nephrectomy was performed. Histopathology evaluation revealed an angiomyolipoma with a focal lesion and clear cell renal carcinoma within the tumor. Conclusion: Limited evidence is available to dictate management of collision tumors of the kidney in the scenario of tuberous sclerosis complex, so a multidisciplinary approach that includes urology, oncology, genetics, and nephrology intervention needs to be considered. No standardized follow-up modality has been established for angiomyolipomas, so patients should be placed under active surveillance, similar to that carried out in cases of renal cell carcinoma.

Gouty Tophus in the Scrotum: An Unusual Extra-Articular Manifestation of Gout.

Background: Gout is a chronic disorder caused by the deposition of monosodium urate crystals in soft tissues. Tophi are granulomatous inflammatory responses to the deposited crystals and manifest as subcutaneous nodules, typically in the first metatarsophalangeal joint but also in the olecranon bursa, Achilles tendon, ears, and finger pulps. Case Report: A 56-year-old male presented to an outpatient clinic with an 8-month history of an expanding scrotal lesion. The patient had no significant family history but had a history of high blood pressure and gout, diagnosed at age 24 years, without current treatment. Excisional biopsy from the ulcerated area of the scrotum was performed for confirmatory diagnosis, and pathology reported gouty tophus. Conclusion: To our knowledge, this case is the first report of a scrotal manifestation of gouty tophus and the second of genital involvement. Awareness of the possibility of genital manifestations of this disease is important because although gouty tophi are rare, they can present in patients with long-term uncontrolled gout.