A 64-year-old woman underwent a screening colonoscopy at the direction of her primary care physician. The colonoscopy revealed an infiltrative, polypoid, and ulcerated large non-obstructing mass in the mid ascending colon that was biopsy-proven to be a well to moderately differentiated invasive adenocarcinoma.
She underwent staging cross sectional imaging that revealed an incidentally diagnosed 16 cm calcified cystic mass (Bosniak IV) arising from the anterior aspect of an atrophic right kidney abutting the right colon and no evidence of metastatic disease.
On physical examination, she had a palpable mobile right upper quadrant. She elected to proceed with concurrent right open radical nephrectomy and a right hemicolectomy for definitive management. Pathologic evaluation revealed Stage III, pT3N1bMx, G2 colonic adenocarcinoma. Examination of the excised renal mass revealed a cystic hypernephroma of low malignant potential.