A Rare Occurrence of Three Primary Malignancies of the Rectum, Breast, and Kidney in the Same Patient: A Case Report and Review of the Literature.

An increasing number of patients with multiple primary cancers are encountered due to improved cancer detection, widespread cancer screening, and better cancer treatment. Here, we report such a patient without a family history of malignancies or a known genetic predisposition developing three primary malignancies of the rectum, breast, and kidney. A 63-year-old female who underwent an anterior resection for rectal cancer was detected to have an elevated carcinoembryonic antigen (CEA) level during a routine follow-up, 8 years after the initial surgery. Clinical examination revealed a left breast lump which was confirmed as invasive ductal carcinoma (pT3 pN0 cM0). Imaging and colonoscopy excluded a local recurrence. However, a right renal lesion suggestive of a renal cell carcinoma was detected (pT1a). She underwent left mastectomy with a sentinel lymph node biopsy and a right partial nephrectomy with a curative intent. Postoperatively, CEA levels declined to normal limits. Management of multiple primary malignancies poses a major challenge. A multidisciplinary approach and tailored decision-making for the individual patient help with the optimum outcome.