Ovarian Cancer: Causes, Symptoms, Treatment and Prognosis — Overview, Diagnosis & Treatment Options | MyMedicPlus

Ovarian cancer arises from three main tissue types: the surface epithelium (epithelial ovarian carcinoma, accounting for approximately 90%), germ cells (germ cell tumors, predominantly in young women), and stromal tissue (sex cord-stromal tumors). Globally, approximately 314,000 new cases of ovarian cancer are diagnosed each year, making it the fifth leading cause of cancer death in women in developed nations. Epithelial ovarian carcinoma (EOC) is the most lethal gynecologic malignancy due to its characteristic late presentation — approximately 75% of patients are diagnosed at advanced FIGO Stage III or IV because early-stage disease produces no specific symptoms. The most common histological subtype is high-grade serous ovarian carcinoma (HGSC), which is characterized by TP53 mutations, frequent BRCA1/2 alterations, and homologous recombination deficiency (HRD). Other subtypes include low-grade serous, endometrioid, clear cell, and mucinous carcinomas, each with distinct biology and chemosensitivity profiles.

Germline BRCA1 mutations confer a 36-46% lifetime risk of ovarian cancer, and BRCA2 mutations confer 10-27% lifetime risk; together they account for approximately 15% of all EOC cases. Lynch syndrome (MLH1, MSH2, MSH6, PMS2 germline mutations) increases ovarian cancer risk by 10-14%. Other hereditary risk conditions include BRIP1, RAD51C, and RAD51D mutations. Non-genetic risk factors include nulliparity (never having been pregnant), early menarche, late menopause, personal or family history of ovarian or breast cancer, endometriosis (linked to endometrioid and clear cell EOC), and polycystic ovary syndrome (PCOS). Protective factors include oral contraceptive use (each year of use reduces risk by approximately 5%), breastfeeding, and tubal ligation. Risk-reducing bilateral salpingo-oophorectomy in BRCA1/2 carriers reduces ovarian cancer risk by more than 80% and is recommended typically between ages 35-45 after childbearing is complete.

Ovarian cancer has been misleadingly described as a 'silent killer,' but clinical studies demonstrate that most patients do experience symptoms — the problem is that these symptoms are non-specific and overlap with common benign conditions including irritable bowel syndrome and gastrointestinal disorders. The Ovarian Cancer Symptom Index identifies four key symptoms that are more frequently and persistently reported by ovarian cancer patients: bloating or abdominal distension, pelvic or abdominal pain, difficulty eating or early satiety, and urinary urgency or frequency. Additional symptoms include back pain, fatigue, and changes in bowel habits. Symptoms that are new in onset, more frequent than 12 days per month, or more severe than usual, and are present for less than 1 year in a woman over 50, should prompt gynecological evaluation. The majority of patients are asymptomatic with Stage I disease, explaining why over 75% of cases are diagnosed at advanced stage.

Initial evaluation includes serum CA-125 (elevated in approximately 80% of HGSC but less reliably in other subtypes), serum HE4 (human epididymis protein 4), and transvaginal ultrasound. The ROMA (Risk of Ovarian Malignancy Algorithm) and ADNEX model combine these markers for risk stratification. CT of the chest, abdomen, and pelvis is performed for staging and surgical planning. FIGO surgical staging (Stage I through IV) is established at the time of primary cytoreductive surgery. Preoperative germline BRCA1/2 testing and HRD (homologous recombination deficiency) testing by genomic scar assays (Myriad MyChoice, Foundation One CDx) are standard, as results guide PARP inhibitor maintenance eligibility. Somatic molecular profiling of the tumor assesses BRCA1/2, HRD, TP53, and other mutations.

The cornerstone of advanced EOC treatment is the combination of maximum cytoreductive surgery (debulking to no gross residual disease) followed by platinum-taxane chemotherapy, typically carboplatin (AUC 5-6) plus paclitaxel (175 mg/m²) administered every three weeks for six cycles, with or without bevacizumab (anti-VEGF). Interval debulking surgery (IDS) after three cycles of neoadjuvant chemotherapy is an alternative for patients who are not immediately surgically operable. First-line PARP inhibitor maintenance therapy has dramatically changed the treatment landscape: olaparib (as monotherapy or combined with bevacizumab) is approved in BRCA-mutated patients; niraparib is approved for all advanced EOC regardless of BRCA or HRD status after complete or partial response to platinum. Veliparib plus chemotherapy followed by veliparib maintenance is an additional regimen. Rucaparib maintenance is used for BRCA-mutated or HRD-positive patients. For recurrent platinum-sensitive disease, retreatment with platinum-based combination chemotherapy plus PARP inhibitor maintenance achieves further remissions. Immunotherapy has limited activity in unselected EOC.

For BRCA1 and BRCA2 germline mutation carriers, risk-reducing bilateral salpingo-oophorectomy (RRBSO) — removal of both ovaries and fallopian tubes — is the most effective prevention, reducing ovarian cancer risk by more than 80% and is recommended after childbearing is complete (typically by age 35-40 for BRCA1 and age 40-45 for BRCA2 carriers). Combined oral contraceptive use for at least five years reduces lifetime ovarian cancer risk by approximately 50%, though this benefit must be weighed against the slight increased breast cancer risk in BRCA carriers. Tubal ligation and full-term pregnancy also reduce risk. Because current screening tests (CA-125 plus transvaginal ultrasound) have not demonstrated a mortality benefit in the UKCTOCS trial, population-level screening is not recommended. Genetic testing for BRCA1/2 and Lynch syndrome should be offered to all women with a personal or family history suggesting hereditary gynecologic cancer risk.

Women who experience persistent and frequent abdominal bloating, pelvic or abdominal pain, difficulty eating or feeling full quickly, or increased urinary urgency — particularly if these symptoms occur more than 12 days per month and are new within the past year — should see a gynecologist or general practitioner promptly. Post-menopausal women with any new pelvic symptoms or an adnexal mass identified on imaging require urgent gynecologic oncology referral. A woman with a strong family history of ovarian, breast, or other BRCA-related cancers should seek genetic counseling to discuss testing, even in the absence of symptoms. Any woman known to carry BRCA1/2 or Lynch syndrome mutations should be established with a gynecologic oncologist for ongoing surveillance and planning of risk-reducing interventions. A new ovarian cyst or adnexal mass in a post-menopausal woman should be evaluated urgently to exclude malignancy.

Stage I: 5-year survival approximately 90%. Stage II: approximately 70%. Stage III: 30-40%. Stage IV: 15-20%. BRCA-mutated patients respond better to platinum-based chemotherapy and PARP inhibitors with improved survival. Optimal cytoreduction (no gross residual disease) is the strongest modifiable prognostic factor. PARP inhibitor maintenance has significantly extended progression-free survival in molecularly selected patients. The prognosis for Ovarian Cancer: Causes, Symptoms, Treatment and Prognosis varies depending on severity at diagnosis, the patient's overall health, and how promptly treatment is initiated. With early diagnosis and appropriate management, many patients achieve good outcomes and maintain quality of life. Regular follow-up with healthcare providers is essential to monitor progress, adjust treatment as needed, and detect any complications early. Adherence to prescribed treatments and lifestyle modifications significantly improves long-term prognosis.