The most common cancers diagnosed in women worldwide are a significant public health concern, with millions of new cases identified annually. Understanding cancer prevalence requires a distinction between cancer incidence (the rate of new diagnoses) and mortality (the rate of death from the disease). Globally, a few specific cancer types account for over half of all new cancer diagnoses in women. Awareness of their characteristics and symptoms is an important part of health maintenance.
Breast Cancer: The Most Diagnosed
Breast cancer is the most frequently diagnosed cancer in women globally, excluding non-melanoma skin cancer. It accounts for nearly one-third of all new cancer cases in women in the United States. About one in eight women will develop invasive breast cancer during her lifetime.
The disease can present with several physical changes that should prompt a medical consultation. The most recognizable symptom is a new lump or mass in the breast or armpit area, which may be hard, fixed, and irregular in shape. Other signs include swelling of the breast, skin irritation, or dimpling, sometimes referred to as an “orange peel” texture. Nipple changes, such as pain, redness, inversion, or any discharge other than breast milk, are also associated with the disease.
The development of breast cancer is linked to a combination of risk factors, including genetics and hormonal exposure. Inherited genetic mutations, such as those in the BRCA1 and BRCA2 genes, significantly increase risk. Hormonal factors are influential, as a woman’s lifetime exposure to estrogen plays a role. This includes early onset of menstruation, late menopause, late age at first full-term pregnancy, or not having children. Other factors, like obesity and heavy alcohol consumption, can also elevate risk.
Secondary Highly Prevalent Cancers
Following breast cancer, the next two most common cancers by incidence in women are lung and colorectal cancer. These cancers are not specific to women but rank highly in female populations. In the United States, lung cancer is the second most common diagnosis and the leading cause of cancer death among women.
The primary risk factor for lung cancer remains tobacco use, including direct smoking and long-term exposure to secondhand smoke. However, an increasing number of cases occur in never-smokers. Symptoms are often vague and can mimic other respiratory conditions, such as a persistent cough, chest pain, and shortness of breath. The high mortality rate stems from its tendency to be diagnosed at an advanced stage when symptoms become pronounced.
Colorectal cancer (CRC), which affects the colon or rectum, is the third most common cancer diagnosis for women. This cancer often begins as non-cancerous growths called polyps, which develop slowly over many years. Key symptoms that indicate a need for evaluation include a persistent change in bowel habits (such as diarrhea or constipation) and rectal bleeding or blood in the stool. Modifiable risk factors for CRC include a sedentary lifestyle, obesity, and a diet high in processed or red meats.
Gynecological Cancers
A group of cancers originates in the female reproductive system, commonly referred to as gynecological cancers, which include uterine (endometrial), ovarian, and cervical cancers. Uterine cancer is the most common of this group, and while its incidence is rising, it often presents with an early, noticeable symptom. Abnormal vaginal bleeding, particularly postmenopausal bleeding, is a frequent sign, allowing for earlier detection and a favorable prognosis.
Ovarian cancer is less common but carries a higher risk of mortality because it is often diagnosed late. This is largely due to its nonspecific and subtle early symptoms, which include bloating, pelvic or abdominal pain, difficulty eating or feeling full quickly, and urinary urgency. Ovarian cancer’s survival rate is significantly lower than that of uterine or cervical cancer, as only about 20% of cases are found in the early, localized stages.
Cervical cancer is the least prevalent of the three in developed countries, primarily due to effective screening and the success of the human papillomavirus (HPV) vaccine. The majority of cases are caused by a persistent infection with high-risk types of HPV. Early stages may not cause any symptoms, but later signs include abnormal vaginal bleeding (such as bleeding after intercourse) or unusual discharge.
The Importance of Early Detection Strategies
Proactive screening is a powerful tool for reducing cancer mortality, as it can detect cancers before symptoms appear or in their earliest, most treatable stages. For breast cancer, average-risk women should discuss starting annual mammography screening between the ages of 40 and 44, and begin yearly screening at age 45. Women aged 55 and older can transition to screening every two years or continue annual screening.
Cervical cancer screening is accomplished through the Pap test (which looks for precancerous cell changes) and the HPV test (which detects the virus that causes the cancer). Screening typically begins at age 25, with a primary HPV test recommended every five years, or co-testing (HPV and Pap test) every five years. For colorectal cancer, regular screening is recommended to begin at age 45 for individuals at average risk. Screening can be performed using stool-based tests or visual exams like a colonoscopy, which is typically done every ten years. Open communication with a healthcare provider is important to tailor these guidelines to individual risk factors and family history.