Abdominal carcinomatosis in women with a history of breast cancer.

Objectives: The goals of this study were to: (1) characterize the etiology of abdominal carcinomatosis, (2) identify clinical features predictive of primary ovarian/peritoneal cancer, and (3) evaluate the survival impact of cytoreductive surgery among patients with advanced ovarian/peritoneal cancer and a history of breast cancer.

Methods: Patients with a history of prior breast cancer undergoing surgical exploration for abdominal carcinomatosis between 1/1/88 and 12/31/02 were retrospectively identified from tumor registry databases. Logistic regression analysis was used to explore clinical characteristics predictive of primary ovarian/peritoneal cancer versus recurrent breast cancer. Survival analyses and comparisons were performed using the Kaplan-Meier and Cox proportional hazard models.

Results: Seventy-nine patients underwent surgery for abdominal carcinomatosis a median of 5.39 years after initial breast cancer diagnosis. Abdominal carcinomatosis was due to primary ovarian/primary peritoneal cancer in 74.7% of cases. A history of Stage I breast cancer [OR = 10.73, 95%CI = 2.6-43.7, P < 0.001] and the lack of a prior breast cancer recurrence [OR = 10.60, 95%CI = 2.5-45.2, P < 0.001] were independently predictive of primary ovarian/peritoneal cancer. Among patients with primary ovarian/peritoneal cancer, optimal (< or =1 cm) cytoreductive surgery was associated with a median survival of 44.0 months compared to 18.0 months for patients with suboptimal residual disease [HR = 6.81, 95%CI = 3.37-13.77, P < 0.0001]. Recurrent breast cancer was associated with a median survival time of 6.4 months.

Conclusions: Among patients with prior breast cancer presenting with abdominal carcinomatosis, early-stage disease and the absence of a prior recurrence were predictive of primary ovarian/peritoneal cancer. Optimal cytoreductive surgery was associated with a significant survival advantage for patients with primary ovarian/peritoneal cancer.