Gastrointestinal carcinomas occurring in breast cancer patients.

Breast cancer patients are reported to have a higher rate of second primary malignancies. We retrospectively reviewed the coexistence of breast and gastrointestinal (GI) tumors in the same patients and the characteristics of the tumors. The charts of all patients more than 35 years of age who were diagnosed with breast cancer and hospitalized for various reasons between 1985 and 2003 were reviewed and those who also had a diagnosis of GI malignancy were then selected. Age and tumor characteristics were evaluated. Out of all the patients, 2,650 had a diagnosis of breast cancer, while 40 (1.5%) also had GI malignancies. Among a comparable group of 70,784 consecutive female patients without breast cancer, 1,292 patients (1.8%) had a diagnosis of GI malignancy. The location of GI tumors in patients with both tumors was as follows: stomach, 6 (15%); right colon, 8 (20%); left colon, 7 (17.5%); sigma, 9 (22.5%); and rectum, 10 (25%). Seventeen of the patients (51.5%) had Dukes C and D tumors, 14 (42.5%) Dukes B, and 2 (6%) Dukes A or in situ. The stage of the others was not identified. The mean age at diagnosis of breast cancer was 68.5 years (range 48-88 years). In 23 (57.5%), GI cancer was diagnosed after breast cancer, in 7 (17.5%) it was diagnosed within 3 months of diagnosing breast cancer, and in 8 (20%) it was diagnosed prior to the diagnosis of breast cancer. Five patients suffered from an additional primary cancer: three endometrial, one lung, one esophageal, and one patient had two additional tumors in the endometrium and thyroid. We conclude that the rate of GI malignancies in breast cancer patients is slightly lower than in comparable patients without breast cancer. GI malignancies tend to be diagnosed later and are found more often in the distal colon.