Endometrial cancer, also known as uterine cancer, has increased fivefold over the past 25 years, making it the most common type of gynecological cancer. This cancer develops in the lining of the uterus.
Despite the surge in new cases, uterine cancer is still relatively overlooked compared to other types of cancers, both in terms of diagnosis and treatment. Experts emphasize the importance of increased disease awareness and improvements in the treatment environment.
June is recognized as Uterine Cancer Month to raise awareness about the severity of the disease, which has been on the rise over the last twenty years. The Korean Society of Gynecologic Oncology initiated this observance last year to underscore the gravity of the disease and promote awareness.
Uterine cancer, commonly referred to as cancer in developed countries, is the most common cancer in women in Western countries. Twenty-five years ago, the annual number of new patients in Korea was 728, making it the least common among the three major gynecological cancers: uterine cancer, cervical cancer, and ovarian cancer. However, by 2021, the number of new patients increased fivefold to 3,749, making it the most common of the three cancers.
However, uterine cancer continues to be neglected compared to other cancers, both in terms of diagnosis and treatment. National health screenings typically do not cover it, prompting women to seek advice from gynecologists when they experience symptoms such as heavy or irregular menstrual cycles, or vaginal bleeding after menopause.
Uterine cancer can advance and spread without noticeable symptoms, making early detection difficult. If detected early, the five-year relative survival rate is 95%. However, if cancer cells have spread to distant organs, known as distant metastasis, it drops sharply to 18%.
Moreover, the stagnation of treatment options for the past 50 years has exacerbated the marginalization of uterine cancer. While other cancers rapidly develop new treatments, the only treatments for uterine cancer have been surgery, radiation therapy, and chemotherapy, which can have side effects.
Professor Kim Jae Won of Seoul National University Hospital who serves as the President of the Korean Society of Gynecologic Oncology said, “Prolonged chemotherapy treatment can cause various side effects, reducing the quality of life and causing long-term discomfort. Given the comparatively lower awareness of uterine cancer compared to other gynecological cancers, there’s a pressing need to improve disease awareness and the treatment environment.”
Uterine cancer has historically faced challenges in finding effective treatments. Given that approximately 75% of all uterine cancer patients relapse within 2-3 years after diagnosis, it is important to determine an effective treatment direction to maintain a healthy life.
Recently, an immunotherapy drug was approved as a new treatment for uterine cancer patients. Keytruda (pembrolizumab), an anti-PD-1 immunotherapy drug, is now considered a viable treatment for uterine cancer patients, regardless of whether they have mismatch repair protein defects.
Cancer cells possess an immune evasion substance called PD-1, enabling them to evade the immune system and thrive unchecked. When the PD-1 of cancer cells binds with the PD-1 of cytotoxic T cells, the T cells lose function and die.
However, when the administered PD-1 antibody binds to PD-1 before PD-1 does, it interrupts the immune evasion signal. Consequently, T cells are no longer influenced by this signal and proceed to eliminate cancer cells.
Uterine cancer patients require a biomarker test to determine eligibility for immunotherapy drugs, with Mismatch repair (MMR) serving as a key biomarker for this purpose. The National Comprehensive Cancer Network (NCCN) guidelines advocate MMR testing for all uterine cancer patients.
Kim advises, “The MMR test is an important means to help me find the appropriate treatment option for patients and for them to receive effective treatment. Treatment options for uterine cancer have expanded with the latest emerging treatments. I hope that patients will not give up on treatment and will continue to the end.”