The early clinical symptoms of ovarian cancer primarily include the following aspects: 1. Discomfort and dull pain in the lower abdomen, with some patients experiencing a sensation of heaviness in the pelvis. Alongside this, patients may also experience poor appetite, nausea, belching, and a feeling of bloating in the stomach. 2. A sensation of abdominal fullness is a clinical manifestation that can appear early in ovarian cancer patients, often caused by cancerous ascites due to the disease. 3. In very few cases, early-stage ovarian cancer patients may feel a mass in the abdomen, typically in leaner patients. 4. Some early-stage patients may experience mild abdominal pain, which generally occurs intermittently and can resolve on its own without the need for medication. 5. Patients may exhibit menstrual irregularities and some endocrine symptoms, such as vaginal bleeding.