March 21, 2019 by John Fernandez
Small Cell Lung Cancer: Early Detection Still A Big Challenge
Usually lacking early-stage symptoms, small cell lung cancer, also known as oat cell cancer, often develops the most aggressive lung tumors. About 10 to 15 percent of lung cancers are small cell lung cancer, and tobacco smoking is the leading cause of the disease. While the cells are small, they grow very quickly and create large tumors.
“It’s unusual for someone who has never smoked to be diagnosed with small cell lung cancer,” said renowned oncology researcher Miguel Villalona-Calero, M.D., deputy director and chief scientific officer at Miami Cancer Institute. People who smoke can decrease their risk of lung cancer by quitting, say experts at the National Cancer Institute.
Additional Risk Factors
In atypical cases, small cell lung cancer can be caused by exposure to radon, secondhand smoke, air pollution, asbestos, diesel exhaust and radiation therapy to the chest to treat other cancers. Age is an uncontrollable risk factor for lung cancer, says Dr. Villalona-Calero. About two out of three people diagnosed with the disease are 65 or older.
Stages of the Disease
For treatment purposes, small cell lung cancer is divided into two stages: Limited stage and extensive stage. “In limited stage, the cancer is confined to one hemithorax since it is dependent on a field of radiation to be able to treat all of the disease,” explained Dr. Villalona Calero. “Extensive stage indicates that the cancer has spread to the other side of the chest or more distant locations in the body, such as the liver, adrenal glands, bones or brain.”
Detecting the Cancer
Small cell lung cancer is difficult to detect early because it typically does not cause symptoms until it is at an advanced stage. “Symptoms usually are related to the spread of the disease,” Dr. Villalona-Calero said. “For example, seizures may indicate the cancer has metastasized to the brain, and bone pain may occur if it has spread to the bones.”
Sometimes, paraneoplastic syndromes may be the first symptoms of lung cancer, Dr. Villalona-Calero adds. These symptoms occur when a hormone-like substance emitted from the lung cancer enters the bloodstream and causes problems with distant tissues and organs, even though the cancer has not spread to those areas.
Patients with a smoking history should talk to their doctor about getting screened for lung cancer. Baptist Health offers a Lung Screening Program to patients at high risk for developing the disease. The low-dose CT screening may detect lung cancer in its early stages – before there are any symptoms – when survival rates are best.
Although small cell lung cancer is an aggressive disease, it responds well to initial chemotherapy and radiation in its limited stage. “Six out of 10 patients will experience a shrinkage in the tumor,” Dr. Villalona-Calero said. Patients with extensive-stage small cell lung cancer also can be treated with chemotherapy. The goals of treatment are to relieve symptoms, maintain quality of life and prolong patient survival with chemotherapy.
Patients diagnosed with small cell lung cancer will discuss their cancer stage and treatment options with a care team comprised of a medical oncologist, radiation oncologist, pulmonologist and palliative care physician. Other oncology specialists involved in the plan of care include physician assistants, nurse practitioners and nurses, respiratory therapists, nutrition specialists and social workers.
Outlook: Clinical Trials Offer Hope
Small cell lung cancer is a recalcitrant cancer – a cancer with a low five-year survival rate. The Recalcitrant Cancer Act, passed by Congress in 2012, acknowledges that more dedicated resources need to be allocated to find a cure for small cell lung cancer.
“We’ve made less progress with this disease in the past 30 years compared to other diseases,” said Dr. Villalona-Calero, who is recognized for his research work in lung cancer, particularly in developmental therapeutics – the development of new and more effective drugs for the treatment of cancer. “Clinical trials in such areas as immunotherapy will help identify new and improved treatments for small cell lung cancer.”