One topic that is rarely considered in the management of SCLC is the role of surgery. The main reason is that the vast majority of patients presenting with SCLC either have extensive disease that has spread throughout the body (2/3 of SCLC presentations) or at least already have rather bulky nodal disease that would make then a less-than-ideal candidate for surgery even if they had NSCLC; the other key component of this bias against surgery is the strong tendency for SCLC to have micrometastatic disease even early in the disease process. That’s why chemo has long been the cornerstone of treatment, even for limited/localized disease, where we have traditionally added chest radiation to chemo in order to provide local disease control.

The estimate is that approximately 5% of patients with SCLC present with “early stage” disease that doesn’t even involve mediastinal (N2) lymph nodes, in the middle of the chest and outside of the lung, but on the same side as the main tumor (abstract here). Even so, most cases of resected SCLC arise from cases in which a small “coin” lesion in the lung that wasn’t suspected to be SCLC is removed either without a preceding biopsy or after a biopsy that didn’t show SCLC – either by being non-diagnostic and suspicious for cancer or showing NSCLC on the limited biopsy but actually being a “mixed” tumor with some elements of SCLC and other elements of NSCLC. This situation of a mixed SCLC/NSCLC tumor is quite uncommon but not rare, and it is conventionally treated as SCLC. So most resected SCLC cases I’ve encountered and heard of from others have been unsuspected SCLC. But should surgery have a role for the small minority of patients with early stage SCLC?

One study that evaluated whether surgery done for responding patients after chemo for SCLC greater than T1-T2 and no lymph nodes involved showed no benefit (abstract here), but that was evaluating patients who received chemo for bulkier disease and then became candidates for possible resection of residual disease. The now defunct Lung Cancer Study Group started with 146 patients with greater than stage I, limited disease SCLC and gave 5 cycles of platinum-base combination chemo (an old standard regimen called CAV that was used primarily before cisplatin/etoposide became more standard). The patients who had a significant response after this chemo were randomized to undergo surgery followed by radiation or just radiation. There was no improvement in survival by adding surgery:

But for patients who have clinical stage I SCLC (T1 or T2, N0) after thorough staging (including CT of chest/upper abdomen, brain imaging, PET scan – I don’t think a bone scan would be clearly help, since a good PET will give you the same information), surgery is an option that is included in some guidelines. It’s important, though, to exhaustively rule out mediastinal disease, so good invasive staging with an endobronchial ultrasound or mediastinoscopy with biopsies is considered an important prerequisite, with a plan to proceed with surgery only if there is no evidence of mediastinal node involvement. If mediastinal nodes are involved, the general recommendation is to pursue chemo and chest radiation instead of surgery. If mediastinal staging is negative, though, guidelines recommend surgery followed by chemo, which can be without radiation for patients without even N1 (lymph nodes within the lung), but would usually add radiation to post-operative chemo in oder to give the best chance for long-term survival.

The long-term survival rates for SCLC that is treated surgically can be up in the 40-50% range, which is higher than we see for limited disease SCLC overall. Some surgeons point to this superior survival as a validation that surgery improves survival, but this ignores the fact that surgery is only a feasible option for a very small subset of SCLC that is unusually limited in its spread and therefore may already have a very different biology from the majority of SCLCs, which have a more typical and early pattern of spread. Nevertheless, surgery is a reasonable initial consideration for the approximately 5% of SCLC patients who present with early stage and the most limited disease, whether their diagnosis of SCLC is know before surgery or discovered incidentally after completely reviewing pathology from a completed resection.

Next, we’ll turn to the question of “consolidation” radiation for any solitary residual chest mass that remains after chemotherapy for extensive disease.