Endometrial serous carcinoma (ESC) is a distinct and less common form of uterine cancer, originating in the lining of the uterus, known as the endometrium. While endometrial cancer is the most common gynecological malignancy, ESC represents a smaller proportion of cases, accounting for less than 10% of all endometrial cancers. Despite its rarity, this subtype is aggressive and has a higher propensity for spread compared to more prevalent forms.
Understanding Endometrial Serous Carcinoma
Endometrial serous carcinoma is characterized by its aggressive behavior and tendency for early metastasis, meaning it can spread beyond the uterus even in its early stages. This differentiates it from endometrioid adenocarcinoma, the most common type of endometrial cancer, which typically behaves less aggressively. ESC is categorized as a “Type II” endometrial cancer, a classification that includes other aggressive subtypes like clear cell carcinoma and undifferentiated carcinoma.
Type II endometrial cancers are associated with poor differentiation of cells and a higher grade. These tumors frequently show specific genetic alterations, such as mutations in the P53 gene and overexpression of HER2/NEU. Distinct histological features of serous differentiation, including marked nuclear atypia, are also present.
Symptoms and Diagnosis
Symptoms of endometrial serous carcinoma often resemble those of more common gynecological conditions. Abnormal vaginal bleeding is the most frequent symptom, manifesting as postmenopausal bleeding, irregular bleeding between periods, or unusual vaginal discharge. Some individuals may also experience pelvic pain, bloating, or a feeling of pressure in the pelvis, particularly as the disease progresses.
Diagnosis begins with a physical examination, including a pelvic exam. Imaging studies such as transvaginal ultrasound, CT scans, and MRI scans are used to visualize the uterus and assess for abnormalities in the endometrial lining. A definitive diagnosis is established through tissue sampling, usually via an endometrial biopsy or dilation and curettage (D&C), where tissue from the uterine lining is collected and examined under a microscope.
Once cancer is confirmed, surgical staging determines the extent of the disease. This procedure typically involves a total hysterectomy (removal of the uterus), bilateral salpingo-oophorectomy (removal of both fallopian tubes and ovaries), and lymph node dissection in the pelvis and around the aorta. An omentectomy (removal of the omentum, a fatty apron-like tissue in the abdomen) and peritoneal washings may also be performed to check for microscopic spread, as ESC has a high risk of spreading to these areas.
Treatment Approaches
Treatment for endometrial serous carcinoma involves a multimodal approach. Surgical intervention is the primary step for almost all patients. This comprehensive surgery typically includes a total hysterectomy, bilateral salpingo-oophorectomy, and extensive lymph node dissection, often including both pelvic and para-aortic lymph nodes.
Following surgery, adjuvant therapies are used to target any remaining cancer cells and reduce the risk of recurrence. Chemotherapy, often a combination of carboplatin and paclitaxel, is a standard adjuvant treatment, particularly for patients with advanced stages or those with positive peritoneal washings. Radiation therapy, including external beam radiation therapy (EBRT) to the pelvis and vaginal brachytherapy, may also be recommended to reduce the risk of local recurrence.
For advanced or recurrent cases, targeted therapy and immunotherapy are also used. Targeted therapies focus on specific molecular pathways involved in cancer growth, such as HER2/NEU overexpression, found in a significant number of ESCs. Immunotherapy, particularly agents like pembrolizumab and dostarlimab, may be used for stage III or IV endometrial carcinoma, especially in cases with specific molecular profiles like mismatch repair deficient (MMRd) tumors.
Outlook and Ongoing Care
The outlook for individuals diagnosed with endometrial serous carcinoma varies, largely depending on the stage at which the cancer is diagnosed and how well it responds to treatment. Despite aggressive treatment, ESC has a relatively high recurrence rate, estimated to be between 31% and 80% even in early stages. The median overall survival for advanced-stage disease has been reported around 32.1 months.
Regular follow-up appointments are crucial to monitor for any signs of recurrence. These appointments typically include physical examinations, and for those with higher stage or grade cancers, routine CT scans of the chest, abdomen, and pelvis are recommended every 6 months for the first 3 years, then every 6 to 12 months for at least the next 2 years. Patients may also benefit from psychological support, as facing a cancer diagnosis and ongoing monitoring can be emotionally challenging.