Kristie L. Kahl: To start, can you discuss what the difference is between a small cell and a non-small cell lung cancer diagnosis?
Wade T. Iams, MD: Those are the 2 major types of lung cancer, and the difference is the cell type within the lung from which the cancer started. Small cell lung cancer begins in neuroendocrine tumors within the lung, whereas non-small cell lung cancer begins in a different set of cells, either in the central lung or out in the periphery. They are the 2 main subtypes differentiated both by site – typically small cell lung cancer in the mid chest and non-small cell often out at the periphery, but can also be in the mid chest – and then treatment modalities.
Kristie L. Kahl: Can you discuss what the non-genomic factors are that are associated with small cell lung cancer?
Wade T. Iams, MD: The biggest association of a non-genomic factors with small cell lung cancer is smoking and cigarette smoking. In particular, heavy cigarette smoking is strongly associated with the development of small cell lung cancer.
Kristie L. Kahl: Can you also explain how this can be a fast-growing disease?
Wade T. Iams, MD: Small cell lung cancer can grow, and typically does, grow more rapidly than non-small cell lung cancer, such that tumor size can double. In aggressive instances, even on the order of days, the tumor grows very rapidly. It's typically not present in a person's body for a prolonged period of time before symptoms develop. And that is very typical of small cell lung cancer.
Kristie L. Kahl: How does the fact that it's fast-growing affect treatment options or treatment decisions?
Wade T. Iams, MD: The fact that small cell lung cancer is so fast growing affects the timeline that we like to start treatment, usually within a week or 2 of making the diagnosis. But it also increases the likelihood that typical chemotherapy will be able to shrink the cancer. And that's what we see in small cell lung cancer, where it grows rapidly. We like to treat it quickly. And our standard chemotherapy options, because of the rapid growth rate, chemotherapy is actually more effective than a non-small cell lung cancer initially.
Kristie L. Kahl: When it comes to the treatment approach, how does a multidisciplinary team come into play with a small cell lung cancer diagnosis and its treatment?
Wade T. Iams, MD: When somebody is diagnosed with small cell lung cancer, the key differentiation is whether that individual is able to be approached with a goal of curing them of their cancer or if our treatment goals are to prolong life and try to maintain quality of life. And the multidisciplinary discussion essentially makes that determination.
Specifically, if the individual has small cell lung cancer within the body, typically within the lung or lymph nodes next to the lung where it started, then chemotherapy plus radiation may be an option and cure would be the goal of that therapy. In rare circumstances, surgeons can also be involved, particularly if there's just 1 spot of small cell lung cancer, then we would rapidly get the surgeons involved and think about doing surgery to remove that. But because of the aggressiveness, we would always follow up surgery with chemotherapy in case there are tiny, small cell lung cancer cells that we haven't yet seen on scans.