Multiple primary malignancies of six organs in a Japanese male patient: A case report.

As a result of recent advances in diagnostic techniques and treatment modalities, the number of patients diagnosed with multiple primary malignancies has been increasing. We report the case of a 79-year-old male with multiple primary malignancies of three histological types in six different organs: Stomach, prostate, colon, urinary bladder, facial skin and pancreas, in chronological order. The first malignancy was upper gastric cancer diagnosed in 1998. The second and third malignancies were prostate cancer and ascending colon cancer, which were diagnosed in 2010. The fourth malignancy was bladder cancer diagnosed in 2011. The fifth and sixth malignancies were squamous cell skin cancer of the right cheek and intraductal papillary mucinous carcinoma (IPMC), respectively, diagnosed in 2014. The gastric cancer, colon cancer, bladder cancer, skin cancer and IPMC were surgically resected. The prostate cancer was treated by anti-androgen therapy. The patient died of local recurrence of IPMC in August 2016. Although multiple primary malignancies are not uncommon, diagnosis of six primary malignancies in a single patient, as reported in the present study, is extremely rare. It is important to understand the characteristics of multiple primary malignancies in order to administer suitable treatment and determine relevant follow-up plans for patients with cancer.