Purists have considered mediastinoscopy, which is invasive staging of the mediastinum through a small incision just at the base of the neck to get down behind the sternum, or breastbone, to be the “gold standard” for determining whether lymph nodes in the mediastinum, or middle of the chest, is involved with a cancer. The procedure is as shown:
(Click on image to enlarge)
As noted in an earlier post, these lymph nodes are very important in initial staging and also repeat staging after induction therapy; specifically, results after surgery appear to be far superior for patients who have no evidence of residual tumor in the mediastinal nodes after induction therapy, whether chemo or chemo and radiation together. Some thoracic surgeons have a patient undergo mediastinoscopy for initial staging followed by a repeat mediastinoscopy after induction therapy in order to assess response. In fact, that is probably the most definitive way to clarify staging before and after induction treatment. However, mediastinoscopies are not only an invasive procedure but are more complicated when done a second time, and they are also potentially more complicated after treatment, especially if radiation is included. One other potential option for reassessing the mediastinum after surgery is to use imaging, with particular attention to the value of PET scans for determining whether there was a response of the mediastinal lymph nodes. Continue reading
It’s only been in the past few years that we have begun to appreciate that there may be many different subgroups of patients who fit within the broader lung cancer population. We now have begun to see differences in the safety and/or activity of certain drugs in never-smokers vs. smokers, patients with adenocarcinomas (and especially bronchioloalveolar carcinoma, or BAC)vs. squamous cell carcinomas or other subtypes, and even in women compared with men. This work has been primarily involved looking back retrospectively at how patients with different clinical characteristics did on various treatments. But we are also starting to move into a new era of collecting tumor tissue and blood on patients with different characteristics in order to learn about the molecular epidemiology (study of various factors in disease) to learn about the different genes and proteins that may define new subgroups of lung cancer, and how they may relate to gender, smoking status, and other factors we already recognize. SWOG trial 0424 is an important new type of research that we hope will move the field forward. Continue reading
For patients with locally advanced NSCLC, the question of whether to pursue a surgical or a non-surgical approach has a great deal to do with the extent of mediastinal (middle of the chest) lymph node involvement. The mediastinal nodes are shown here:
First, at the time of initial staging, patients with bulky (>3 cm) disease in the mediastinum, or those with disease involvement more than one nodal station, are less appropriate candidates for surgery than those with non-bulky and single-station disease. In fact, a French retrospective review of over 700 patients with N2 disease who underwent surgery at any of six centers (Andre abstract here) demonstrated that there are quite varied long-term outcomes for different patients that all fall under the same stage of IIIA with N2 disease, and that the patients with a single-station and microscopic involvement (as opposed to clinical enlargement that is visible as abnormal on CT (greater than 1 cm in diameter):
That was in a group of patients who underwent surgery, and just a view of how patients did after the fact. Continue reading