Among woman cancers, endometrial cancer, ovarian cancer, and cervical cancer are the most common gynecological cancers. Cervical cancer is the only one that can be screened (Pap smear and human papillomavirus testing). While there are no effective screening tools for endometrial and ovarian cancers.

Endometrial Cancer
Endometrial cancer is usually presented with abnormal vaginal bleeding or postmenopausal bleeding. Although most cases of postmenopausal bleeding are benign causes, they could also be caused by endometrial cancer. Early examination of postmenopausal bleeding often leads to the detecting of early-stage endometrial cancer, which has a good prognosis and high cure rate. Therefore, it is important for women to seek medical attention promptly if they experience postmenopausal bleeding.

Ovarian Cancer
The ovaries are located in the pelvic cavity and are not easily palpable. Early symptoms of ovarian cancer are not obvious and often similar to gastrointestinal symptoms, hence ovarian cancer usually diagnose at late-stage in most cases. The CA-125 blood test is commonly used as ovarian tumors marker during medical check-ups, but many factors can affect CA-125 levels, and some ovarian cancers do not show elevated CA-125 levels. Therefore, middle-aged women experiencing lower abdominal discomfort, unexplained gastrointestinal symptoms, or abdominal bloating should seek gynecological evaluation for early detection and further treatment.

Cervical Cancer
The majority of cervical cancers are associated with human papillomavirus (HPV) infection. HPV is a DNA virus that infects the skin and mucous membranes of the body. HPV has over 200 types, classified into low-risk and high-risk types. HPV types 16 and 18 are the most common high-risk types associated with cervical cancer. More than 70% of cervical cancers are caused by HPV types 16 and 18. HPV types 6 and 11 are the most common low-risk types, which can cause genital warts. In Taiwan, the most common HPV types found in cervical cancer patients are 16, 18, 52, and 58.

HPV infections are usually asymptomatic and often cleared by human immune system. Persistent HPV infections can increase the risk of developing cervical cancer. HPV testing can detect high-risk HPV types. HPV vaccination can prevent over 70% of cervical cancers. It is important to encourage HPV vaccination and regular cervical cancer screenings even after vaccination.

Cervical cancer screening (Pap smear) has led to a decrease in cervical cancer incidence in Taiwan. The Ministry of Health and Welfare has implemented expanded cancer screening, including cervical cancer screening with Pap smear can begin at aged 25, starting from 2025.

Cervical Cancer Screening in Taiwan:
- Women aged 25-29: Screening every 3 years
- Women aged 30 and above: Recommended to have a Pap smear every 3 years
- HPV testing for women aged 35, 45, and 65

In conclusion, cancer screening is crucial for early detection and improved treatment outcomes. Regular cervical cancer screening can be early detection of precancerous lesions and allow for timely intervention. It is important for women of childbearing age to undergo regular cervical cancer screenings.