Fallopian tube cancer

ALSO KNOWN AS: Fallopian tube adenocarcinoma, Fallopian tube sarcoma, Fallopian tube mixed mesodermal tumor, broad ligament tumor

RELATED CONDITIONS: Cancer of the uterus, cancer of the ovary, peritoneal carcinomatosis

DEFINITION: Fallopian tube cancer is a rare cancer in one of the Fallopian tubes, which lie on both sides of the top of the uterus (womb). These tubes serve as the site of fertilization for oocytes (eggs) released from the ovary and sperm ascending from the vagina, and then as passageways by which the zygote (fertilized egg) returns to the uterus to implant and where the fetus grows and develops. Cancer of the Fallopian tube is primary (originating in the Fallopian tube) in 10 to 20 percent of cases. Most Fallopian tube cancers are metastatic from the ovary, uterus, or gastrointestinal tract (stomach and intestines).

Risk factors: Major risk factors for Fallopian tube cancer include chronic inflammation in the form of endometriosis or pelvic infections, a history of infertility, and low parity (fewer than two children). The average age at diagnosis is fifty-nine. Most diagnoses occur in North America in individuals between twenty-six and eighty-five. Oral contraceptive use and pregnancy may reduce a woman’s risk of Fallopian tube cancer.

Individuals of Northern European or Ashkenazi Hewish descent are at an increased risk of developing this cancer. Additionally, a family history of breast, ovarian, or fallopian tube cancer or the presence of inherited conditions like Lynch syndrome and Peutz-Jeghers syndrome increases the risk of fallopian tube cancer.

Etiology and the disease process: Based on molecular studies, cancer of the Fallopian tube and ovary share abnormalities of the genes TP53 and ERBB-2, suggesting similar genetic risks and environmental factors. Mutations in the BRCA1 and BRCA2 genes have also been linked with Fallopian tube cancer risk. Mutations in breast cancer 1, early onset gene (BRCA1), and mutations in one copy of breast cancer 2, early onset gene (BRCA2) are associated with increased risk of Fallopian tube cancer.

Incidence: Fallopian tube cancer is the rarest cancer involving the female genital tract, accounting for approximately 1 percent of all gynecologic cancers are Fallopian tube cancers, but because they are closely associated with ovarian cancer, they may have a higher actual incidence. The incidence of Fallopian tube cancer in the United States is 3.6 cases per million women per year, with approximately three to four hundred cases diagnosed each year. Symptoms associated with cancer of the Fallopian tube include an abnormal, watery vaginal discharge or excessive bleeding. Such symptoms occur in approximately 50 percent of those with Fallopian tube cancer. Pain and a palpable pelvic mass are infrequently associated with Fallopian tube cancer. Occasionally, the pain associated with Fallopian tube cancer mimics appendicitis.

Screening and diagnosis: No routine screening exists for Fallopian tube cancer. Usually, the diagnosis of Fallopian tube cancer is made at the time of exploratory surgery to evaluate the patient’s symptoms, such as pelvic pain or a mass. Aside from nonspecific symptoms and the triad of symptoms in postmenopausal women (pelvic pain, a pelvic mass, and vaginal bleeding or discharge), the diagnosis should be suspected when cancer cells show up on microscopic evaluation of vaginal discharge with a negative Pap smear and biopsy of the uterus. An abdominal mass can be further evaluated with a pelvic ultrasound, computed tomography (CT) scan, magnetic resonance imaging (MRI), or a laparoscopic examination of the pelvis (outpatient surgery performed through the belly button with a small, lighted instrument). Definitive diagnosis of primary Fallopian tube cancer, as opposed to metastatic cancer, requires that the tumor be contained within the cavity of the Fallopian tube (lumen), the lining of the Fallopian tube (mucosa) be involved with the tumor, and a transition be demonstrated between the portion of the tube involved and that not involved with cancer. Cancer of the Fallopian tube is based on the International Federation of Gynecology and Obstetrics (FIGO) staging guidelines. Stage 0 is cancer limited to the lining of the Fallopian tube (mucosa). Stage I is cancer limited to one tube with extension into the muscular layer of the tube but not to the external surface of the tube. Stage II cancer involves one or both tubes with extension beyond the Fallopian tube. Stage III cancer involves one or both tubes with spread beyond the pelvic cavity. Stage IV cancer involves one or both Fallopian tubes with distant metastases (for example, the lungs). Unlike ovarian cancer, which is usually advanced at the time of diagnosis, approximately 50 percent of Fallopian tube cancers are Stage I or II at the time of diagnosis, and 50 percent are Stage III or IV.

Treatment and therapy: Because Fallopian tube cancer is generally diagnosed during surgery, staging is performed at that time to determine the extent of the disease and optimal treatment. Treatment includes a hysterectomy (removal of the uterus), a bilateral salpingo-oophorectomy (removal of both Fallopian tubes and ovaries), inspection of the surfaces of the lining of the abdominal cavity (the peritoneum) for cancer cells, sampling of lymph nodes, and removal of the omentum (a fatty layer covering the intestines).

For Stage I disease, surgery alone is recommended unless the peritoneum is positive. In that case, postoperative radiation or chemotherapy is offered. For Stages II through IV, postoperative chemotherapy is the standard treatment. A second laparoscopy is often performed after chemotherapy or radiation therapy is completed to confirm the disease's control. The cancer antigen 125 (CA 125) blood test can help monitor disease recurrence.

Prognosis, prevention, and outcomes: The five-year survival rate for all stages of Fallopian tube cancer is approximately 55 percent.

Patients diagnosed with Stage I Fallopian tube cancer have five-year survival rates of 65 percent; those with Stage II, 50 to 60 percent; and those with Stages III and IV, 10 to 20 percent. Patients diagnosed with the earliest stage of Fallopian tube cancer, in which the cancer is limited to the tube lining, have five-year survival rates of 95 percent. Patients whose cancers have spread to the tube walls have five-year survival rates of 53 percent. The five-year survival rate drops to 45 percent if the cancer has spread beyond the Fallopian tube.

Bibliography

Berek, Jonathan S., et al. "Cancer of the Ovary, Fallopian Tube, and Peritoneum: 2021 Update." International Journal of Gynecology & Obstetrics, vol. 155, 2021, pp. 61-85. doi.org/10.1002/ijgo.13878.

"BRCA1 Gene." MedlinePlus, medlineplus.gov/genetics/gene/brca1. Accessed 20 July 2024.

"BRCA2 Gene." MedlinePlus, medlineplus.gov/genetics/gene/brca2. Accessed 20 July 2024.

"BRCA Gene Mutations: Cancer Risk and Genetic Testing." National Cancer Institute, www.cancer.gov/about-cancer/causes-prevention/genetics/brca-fact-sheet. Accessed 20 July 2024.

Carlson, Joseph W. Tumors of the Ovary and Fallopian Tube. American Registry of Pathology, 2023.

"Fallopian Tube Cancer." City of Hope Cancer Center, 9 May 2022, www.cancercenter.com/cancer-types/ovarian-cancer/types/fallopian-tube-cancer. Accessed 20 July 2024.

"Fallopian Tube Cancer." Cleveland Clinic, 10 May 2024, my.clevelandclinic.org/health/diseases/21540-fallopian-tube-cancer. Accessed 20 July 2024.

Stasenko, Marina, et al. "Fallopian Tube Carcinoma." Journal of Oncology Practice, vol. 15, 2019, pp. 375-382. doi.org/10.1200/JOP.18.00662.