To summarize the clinicopathological features of nine patients with double primary breast and ovarian cancer, and explore the possible causes and prevention and treatment measures.

The clinical records of nine patients with double primary breast and ovarian cancer in the Second Affiliated Hospital of Chongqing Medical University and the Central Hospital of Mianyang from January 2010 to December 2016 were retrospectively analyzed. They were followed up for 24-312 months, median 120 months.

Among these patients, six patients firstly had breast cancer, two patients firstly had ovarian cancer and one patient had synchronal breast and ovarian cancer. Two patients received the detection of BRCA genes, including one with BRCA1 gene mutation. The first clinical symptom of the breast was mass in nine cases. The first clinical symptom of the ovary was abdominal distension in six cases, unusual vaginal bleeding in two cases and the mass in one case. Five patients with immunohistochemical results were ER negative, including four patients with triple-negative breast cancer. All patients underwent radical mastectomy for breast cancer and chemotherapy, three patients received postoperative radiotherapy, one patient had endocrine therapy of tamoxifen after surgery and none received anti-HER-2 therapy. Except one patient who refused ovarian surgery, the other eight patients underwent the staging surgery of ovarian cancer. All patients received intravenous chemotherapy, three patients received intraperitoneal infusion chemotherapy and none received radiotherapy. The median age of onset in nine patients was 46 years old(range: 36-51 years). The median interval of the two cancers was 93 months(range: 0-300 months) and the median progression-free survival after the diagnosis of the second cancer was 19 months(range: 7-22 months). Seven patients had the recurrence or metastasis of ovarian cancer, and three patients died in the follow-up. The median interval of the two cancers in six patients without family breast/ovarian cancer history was 122 months while three patients with family history had a median interval of 21 months. Three patients who were diagnosed with the first cancer at the age<45 years had a median interval of 258 months between the onsets of two cancers; six patients who were diagnosed with the first cancer at the age≥45 years had a median interval of 36 months.

Patients with double primary breast and ovarian cancer have a young age of onset. Most patients have obvious clinical symptoms and advanced stage when they are diagnosed with ovarian cancer. The patients with family history tend to have a short median interval between the onsets of two cancers. These patients are mainly treated by surgery and chemotherapy.