Radiation Therapy

In my last post I covered much of the controversy about whether patients with stage IIIA, N2-node positive NSCLC should be treated with induction therapy (chemotherapy or chemo/radiation) followed by surgery, or an alternative approach of chemo along with radiation delivered at a definitive dose (curative, not just the supplemental, lower doses used in induction therapy).

It's over, and I won (did you doubt me?).

I'm heading off today to Hawaii (Maui), which I must hasten to add is for a conference, the Eighth International Lung Cancer Congress, not just a vacation, although working in Hawaii often seems better than time off at home. The meeting not only includes a lot of good lectures and debates, but it gives us the opportunity to actually discuss the importance and implications of the trials that were just presented a few weeks before at ASCO.

As I described in prior post, prophylactic cranial irradiation (PCI) is established as a treatment approach for patients with LD-SCLC who have had a complete or "good partial" response to chemo and radiation. Some physicians also recommend PCI for patients with ED-SCLC who have experienced a very good response, since about 10% of the patients on the PCI trials that led to our current recommendations had ED-SCLC.

One of the more common approaches to treating stage IIIA NSCLC with N2 lymph nodes (mediastinal, or mid-chest, on the same side as the primary tumor) is chemotherapy or chemoradiation before surgery. For those who recommend induction therapy (treatment before planned resection), there is a pretty even split between those who recommend chemotherapy alone and those who recommend chemo with concurrent radiation. So how do knowledgeable people come to different conclusions, and who is right?

A novel agent called motexafin gadolinium (MGd), with a marketed name of Xcytrin, has been studied as a potential neuroprotectant as well as radiosensitizer that may allow patients with brain metastases to do better when it as added to whole brain radiation therapy (WBRT) than they would with WBRT alone.

We'll cover the general management principles for the more typical situation of patients with multiple brain metastases from lung cancer soon, but today we’ll cover the special situation of the patient who has a brain metastasis identified as the ONLY area of metastatic disease (generally referring to NSCLC, since SCLC has such a high tendency to spread distantly early in its history). Recall that metastatic, or stage IV, lung cancer, is treated with a palliative approach, due to the inability to achieve prolonged survival except in very rare cases.

There is still plenty of active debate about whether patients with stage III NSCLC who have mediastinal lymph nodes, the ones in the middle of the chest between the lungs but on the same side as the main tumor, should receive surgery in some circumstances or not.

I recently wrote a post about combining chemo and radiation after surgery for unsuspected stage IIIA N2 node-positive NSCLC (if discovered prior to surgery, it is more common to administer chemo and/or radiation before surgery). In the comments that followed it, Carlos brought to my attention a study that I neglected to mention a recently published trial.

Adjuvant chemo has become increasingly established as having a survival advantage, at least for the general population of stage II and IIIA patients, and potentially for some with earlier stage disease (see adjuvant chemo post). However, post-operative radiation therapy, or PORT, does not have an established role.