What factors should be considered in determining treatment for a patient with cancer?
How do the outcomes of cancer clinical trials influence treatment decision making?
What treatment modalities exist and under what formats are these provided?
What are the main classes of systemic and radiation therapy?
Cancer is a heterogeneous disease affecting all age groups, nationalities, and socioeconomic classes. Cancer patients, along with their families and friends, experience enormous social, emotional, and economic effects. In the United States, the National Cancer Institute (NCI) collects cancer-related statistics and produces the Surveillance, Epidemiology, and End Results (SEER) database (seer.cancer.gov).
It is estimated that in 2010 in the United States, 1,529,560 people will be diagnosed with and 569,490 will die of cancer. The lifetime risk of developing cancer is 1 in 2. In the United States in 2007, cancer was second to heart disease as the leading cause of death (23.2% versus 25.4%). Compared with death rates from 1975, the percentage of deaths from cardiac causes has decreased while cancer-related deaths have increased. Allowing for this, the absolute death rate among those diagnosed with cancer continues to decline. In North America, the most frequent incident cancers among men are prostate, lung, and colon and among women are breast, lung, and colon. Lung cancer is the leading cause of cancer-related deaths for both men and women. The second commonest cause of cancer deaths are prostate (males) and breast (females). Colon cancer is the third leading cause of cancer death for both sexes.
A 64-year-old woman was admitted with bowel obstruction due to metastatic rectal cancer. She has undergone many previous therapies. Some were attempts to cure the disease, and others were given with palliative intent. She was diagnosed eight years previously with stage III rectal cancer after presenting with rectal bleeding and was initially treated with curative intent consisting of 5-flurouracil and concurrent radiation therapy followed by surgery consisting of a total mesorectal resection. She then received additional chemotherapy. Three years later, her cancer recurred in the right lobe of the liver. She underwent a right hepatic lobectomy followed by further chemotherapy. She was free of disease for two years, but has recently been discovered to have peritoneal carcinomatosis and retroperitoneal lymphadenopathy. She was given radiation therapy to the lymph nodes to treat pain and followed by chemotherapy.
This case demonstrates the continuum of cancer therapy intent. At initial presentation, the goal of treatment was to cure the disease. With subsequent cancer recurrences, the goals evolved. With the first recurrence, the intent was to potentially cure the patient given the isolated liver disease. Although not cured, the surgery prolonged a disease-free state and improved quality of life. Later recurrences were associated with strategies to palliate symptoms and transition to end-of-life care. This case demonstrates use of multiple treatment modalities (systemic, radiation, and surgical) used according to different principles (neoadjuvant, adjuvant, ...