Fallopian tube cancer occurs when cells in the fallopian tubes multiply out of control and form a tumor.

 The fallopian tubes are the passageways that connect the ovaries and the uterus.

As this tumor grows, it can eventually press against the inside of the fallopian tube, stretching the tube and causing pelvic pain. Over time, the tumor can eventually spread throughout the pelvis and abdomen.

Fallopian tube cancer is very rare. It accounts for less than 1% of all cancers of the female reproductive organs. Only 1,500 to 2,000 cases have been reported worldwide, primarily in postmenopausal women. It is more common for cancer to spread to a fallopian tube from elsewhere in the body (usually the ovary, breast or endometrium) than for a new cancer to develop in the fallopian tube.

Scientists don't know whether any environmental or lifestyle factors increase the risk of this cancer. Researchers are looking at the possibility that there might be some inherited (genetic) tendency to develop the illness. There is some evidence that women who inherit a mutation in the BRCA1 gene, a gene already linked to breast and ovarian cancer, seem to have an increased risk of developing fallopian tube cancer. Recent research has confirmed this. In one recent analysis of several hundred women who were carriers of the BRCA1 gene mutation, the incidence of fallopian tube cancer was increased more than 100-fold. Likewise, a substantial proportion of women with the diagnosis of fallopian tube cancer test positively for either the BRCA 1 or BRCA2 gene mutation. Recent recommendations suggest that any woman with a diagnosis of fallopian tube cancer be tested for the BRCA mutations.

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