Ovarian cancer is unique in that there are no early detection tests available. By the time it is discovered, over 70% of cases are stage 3 or 4. Consequently, it has the highest mortality rate among the three major women's cancers (ovarian cancer, cervical cancer, and breast cancer). Ovarian cancer, once synonymous with a death sentence, has transformed into a treatable disease. This miracle is due to genetic testing and targeted therapies.
On the 22nd of last month, obstetrician Professor Kim Jae-hoon, met at Gangnam Severance Hospital in Seoul said, “In the past, we would give up on treating ovarian cancer, but now it has changed.” He noted, “With advancements in genetic analysis technology, more patients can use targeted therapies,” adding, “As a result, the five-year survival rate has increased from 40% to near 70%.” Targeted therapies kill only cancer cells.
Professor Kim is a 30-year expert in the field of gynecological cancer treatment, currently serving as the director of the Ovarian Cancer Center at Yonsei University Gangnam Severance Hospital. He mentioned, “Previously, only ovarian cancer patients with specific genetic mutations could use targeted therapies, but recently it has been revealed that other patients with different genetic characteristics also show high treatment efficacy.” He also stated that analysis tests for selecting these patients have been introduced, providing treatment opportunities for over half of ovarian cancer patients.
The ovaries are female reproductive organs that produce eggs and secrete female hormones, roughly the size of almonds. However, it is difficult to detect cancer in this area. Symptoms such as abdominal bloating, indigestion, and abdominal pain can easily be overlooked.
Professor Kim said, “While ovarian cancer can be somewhat suspected through transvaginal ultrasound or CT (computed tomography) scans, a biopsy is essential for a definitive diagnosis,” and added, “Due to its location within the abdominal cavity, the cancer tissue must be removed through open surgery.” Thus, surgery is unavoidable for diagnosis.
If diagnosed with ovarian cancer, various treatments are carried out. These include surgery to remove the cancer cells from the ovaries, chemotherapy that aims to kill the cancer cells using anticancer drugs, immunotherapy, and targeted therapies. The standard chemotherapy regimen combines the anticancer drugs carboplatin and paclitaxel, but recently, the targeted therapy known as “PARP inhibitor” has gained attention for its high treatment efficacy and lower side effects.
Targeted therapies selectively kill only cancer cells without affecting normal cells. This results in fewer side effects and greater treatment effects. However, not all patients can use targeted therapies. Among ovarian cancer patients, 22% have mutations in the BRCA (Breast Cancer gene) that produces tumor suppressor proteins, making them susceptible to cancer. Thus far, only patients with BRCA mutations have been eligible for targeted therapies.
Recently, another 'target' of targeted therapies beyond BRCA was discovered. This genetic trait involves a failure to repair DNA double-strand breaks (HRD). Some BRCA mutation patients also possess HRD. The good news is that HRD encompasses half of all ovarian cancer patients. Now, the eligibility for targeted therapy prescriptions has expanded from 22% to 50%.
Professor Kim noted, “Thanks to the broadened target therapy eligibility, the five-year survival rate for stage 3 and 4 patients has increased from around 30-40% to nearly 70% recently,” and remarked, “The insurance coverage for the PARP inhibitor, which applies to both BRCA mutations and HRD, has also played a significant role.”
For patients diagnosed with ovarian cancer to receive targeted therapy prescriptions, they must undergo genetic testing to determine the presence of BRCA mutations and HRD. While BRCA mutation status can be determined via a blood test, HRD diagnosis has been challenging.
Recently, next-generation sequencing (NGS) technology, which rapidly decodes massive genetic information, has been applied to HRD testing. Since 2020, it has become an essential test for ovarian cancer patients. Now, both BRCA mutations and HRD information can be obtained simultaneously. Professor Kim stated, “The introduction of HRD testing and the expansion of targeted therapy qualifications significantly enhanced the five-year survival rate for ovarian cancer.”
The issue lies in the testing expenses. HRD testing does not yet have health insurance coverage, making it a significant financial burden. Currently, the cost for a single test exceeds 2 million won. Professor Kim said, “Ovarian cancer has a high recurrence rate and ranks among the highest for lifetime healthcare expenditures among cancers,” adding, “If more patients could benefit from insurance coverage, the survival rate for ovarian cancer would increase even further.”
Professor Kim is contributing not only to patient care but also to the research of diagnosis and treatments. He currently serves as the head of the Korean Gynecological Cancer Bank (KGCB). Having realized the necessity of a biobank during his training at Harvard Medical School in the early 2000s, he pursued establishment through a government project upon returning home and opened the KGCB in 2012. The biobank is a biorepository that preserves human specimens.
The Korean Gynecological Cancer Bank stores over 60,000 human specimens related to gynecological cancers, including tissues, blood, and cells. These specimens are provided free of charge for research by universities, research institutions, and pharmaceutical companies. Professor Kim is also currently researching new ovarian cancer diagnostic methods using the specimens from this bank.
Professor Kim stated, “Ovarian cancer has a low incidence rate and has attracted less attention compared to other cancers,” and added, “As nearly half of the patients are still excluded from treatment targets, I will focus on both treatment and research.”