I’m very proud to have teamed up with Dr. Ross Camidge from the University of Colorado in writing an editorial piece for the current issue of the Journal of Thoracic Oncology called “Have Mutation, Will Travel: Utilizing Online Patient Communities and New Trial Strategies to Optimize Clinical Research in the Era of Molecularly Diverse Oncology”. This commentary was based on our observation that the world of lung cancer, and oncology in general, is changing quickly, that our longstanding practices for research are poorly equipped to meet the demands of a new world of “molecular oncology”, and that we can overcome these challenges by having clinical researchers collaborate far more actively with online patient communities and by revising some of our rather sclerotic (if not ossified) methods for conducting clinical research.
If you’re wondering why there are now a bunch of links that seem very similar in their description listed on the right side bar of the lung cancer subject area, it’s because we’re trying to determine the format that works best for people. One labeled Recent Lung/Thoracic Forum Activity shows a list just of recent threads in lung cancer, a nice table that has the ability to move from page to page from the bottom. It has the shortcoming of only showing one forum at a time, so you can’t see recent forum activity for other areas like Radiation or General Cancer Questions, etc.
On the other hand, the Lung Forums Recent Activity (beta) link takes you to a different page that shows scrollable lists of multiple forums all from one page; in this case, the lung cancer forum is at the top, followed by all of the general cancer forums after that. The formatting isn’t quite as nice, at least not yet, but it has the convenience of putting forum activity from many areas all on one page. There’s also a last link labeled All GRACE Forums Recent Activity that even includes the links to other cancer-specific forums like breast, pancreatic, and head/neck in the scrollable format on one page… though we anticipate that relatively few people participating in discussions about lung cancer will also be avidly following discussions in breast cancer or other cancers.
As I mentioned in my post about the transition into March, I recently participated in a Medscape program on “A Multidisciplinary Approach to Incorporating Genotyping in NSCLC“. It requires people to register on Medscape, and it’s a program with docs as the target audience, but I think it would be of potential interest to some of the GRACE members.
I’m just now returning from the International Association for the Study of Lung Cancer’s “12th Annual Targeted Therapies in Lung Cancer Conference”, which consisted of about 170 very brief talks about several classes of agents, as I described in my last post. Some of these are likely to emerge as viable, truly beneficial therapies for patients; many others will fall by the wayside. Because it’s really not feasible to discuss such a broad range of agents that we only get a snapshot view of, I thought I’d try to convey what emerged as five core takeaway points from the 2012 iteration of this important meeting.
Many of you already participating on the lung cancer section of the GRACE site have seen the first few responses by Dr. Aggarwal, though they have preceded my proper introduction of her. Apologies — we had talked a few months ago about having her start sometime around now, though I hadn’t anticipated her laudable enthusiasm and courage to jump right in. So let me now provide a little background.
Dr. Charu Aggarwal is an Assistant Professor in the Hematology/Oncology Division at the University of Pennsylvania, where she has a particular focus on lung cancer. She started her medical training at the Lady Hardinge Medical College in New Delhi, then came to the US and did a Master’s in Public Health at the University of Alabama, Birmingham. She then did her internship and residency training in internal medicine at the State University of New York, Buffalo before moving to Philadelphia to do her medical oncology fellowship training at the Fox Chase Cancer Center. Last year she moved to the University of Pennsylvania to join their faculty.
In my thoracic oncology tumor board today, we discussed a situation that comes up fairly often: a patient has a collapsed lung lobe from a tumor near the middle of the chest, with some regional lymph nodes involved, and the surgeon thinks he’s likely to need the whole lung removed because the location of the tumor is nestled in just the wrong place. The patient has enough lung function to undergo surgery, but losing an entire lung (pneumonectomy) is a big loss, and he’s already only a debatable candidate to be able to undergo surgery safely. So the question emerges, “Can we give pre-operative chemotherapy specifically with the intent of shrinking a cancer enough to enable a less extensive surgery than would be needed if no pre-operative therapy is done?”
It’s a question that doesn’t have a clear answer. The concept of “downstaging” a cancer with neoadjuvant (pre-operative) chemotherapy or chemo/radiation is an appealing potential appeal of the strategy, but there isn’t clear evidence that it really works. In the ChEST trial that has been recently published that compared pre-operative cisplatin/gemcitabine chemotherapy followed by surgery to surgery alone, the recipients of neoadjuvant therapy were less likely to have undergone a pneumonectomy (17% vs. 25%) and more likely to have received a lobectomy (70% vs. 60%) . On the other hand, the SouthWest Oncology Group (SWOG) ran a similar neoadjuvant chemotherapy trial and found that there were no differences in the pneumonectomy rates with or without pre-op chemo — 17% in both arms. What gives? Continue reading
One of the very common themes that emerges in the questions from the GRACE community is whether a “local therapy” such as focal radiation or surgery could be useful for advanced NSCLC. There’s an FAQ question and answer about the general concept of why treatment directed to a specific area (i.e., a “local therapy”, as opposed to a systemic therapy that works throughout the body) isn’t typically recommended for metastatic cancer, but local therapies are still often discussed and may have a role for patients who have more advanced NSCLC. Very often, I’m coming down against the concept of local therapy when people here ask, but there are some settings in which local therapies are very appropriate, in addition to others where we might strongly consider it. I work very closely with my radiation oncologists, my thoracic surgeons, and my interventional pulmonologist — who all provide local therapies — and we are all part of a team that share patients depending on their case needs. But I do feel that local therapies are all too often misapplied, whether because of financial motivations of the practitioners or the misguided, unclear rationale for doing it (“magical thinking“), which I see as creating a fundamental disconnect between a patient’s expectation and the reality of what such an intervention can deliver.
The clearest role for local treatments in metastatic lung cancer is to improve QOL and reduce symptoms. Indeed, that’s exactly the place where they have a clear role. Radiation, for instance, is appropriate in metastatic disease in four basic circumstances:
1) brain metastases, which cause symptoms from local growth and swelling, or usually will very soon after detection, if not treated effectively
2) hemoptysis (coughing up blood), where radiation can treat local bleeding from erosion of the cancer into adjacent blood vessels quite effectively
3) local pain, such as from a bone or soft tissue lesion, in which case radiation-induced shrinkage can reduce that and improve pain effectively
4) airway compression, in which case radiation-induced response can lead to better air movement
Radiation isn’t the only form of local therapy. Mechanical ones like surgery (removing a single brain metastasis, treating a collapsed vertebra with kyphoplasty) or interventional pulmonology techniques (removing tumor from within an airway or placing a stent in an airway compressed from outside of it), may also be helpful in many cases. Other common local therapies are a pleurodesis or placement of a PleuRx catheter to control shortness of breath and the cough that can accompany a recurrent large pleural effusion. These interventions are all extremely appropriate and offer quality of life benefits/symptomatic benefits first and foremost, though they may also improve survival. Continue reading
The idea is simple enough: we want to identify the patients with a resected early stage NSCLC that has a high risk of recurrence, so that we can give them additional therapy, usually in the form of post-operative (adjuvant) chemotherapy, while sparing this additional challenging and even potentially dangerous therapy for the people who have a more favorable prognosis. Right now, the system we generally use to identify patients at higher vs. lower risk of recurrence is based on lung cancer staging, which is based on the size of the tumor, whether the cancer invades nearby structures, the extent of lymph node involvement, and whether there is spread to distant parts of the body. That staging system works reasonably well, but we also know that there are many patients with early stage disease who fall below the general threshold for adjuvant chemotherapy but will still recur, while many people who receive chemotherapy were already cured from the surgery alone. This leads us to the question, “Can we refine our prognostic ability by looking at the molecular characteristics of the cancer?”. We keep learning that molecular features of a cancer are becoming less opaque and are very important, and we also know that some tumors of the same stage respond much more aggressively than others.
We’ve looked at molecular markers (one or a few distinct variables that may be particularly important) and genetic signatures (an overall pattern of the genetic activity level of an often complex collection of genes) for a few years. For instance, ERCC-1 is an enzyme that was shown in a retrospective analysis of a single trial was prognostic for survival and predictive of the benefit or lack of benefit from adjuvant cisplatin based chemo, and an analysis of a different adjuvant chemotherapy trial demonstrated that a molecular signature was also prognostic of better or worse survival and predictive of which patients benefit from chemotherapy. But these methods have had limitations and detractors. Markers that are called positive or negative, high or low by immunohistochemistry (IHC), which is essentially the intensity and frequency of a protein on the surface of cancer cells, is a subjective interpretation. And work on molecular signatures has generally required “snap frozen” tissue, which requires special preparation right at the time of the surgery, and this is a technical challenge that is not widely feasible. Continue reading
One of the lung cancer surgeons I work closely with sent me and a couple of the radiation oncologists at my center a report that just came out from a group in Kyoto highlighting that they have a seen a notable proportion of their patients develop late recurrences, even well beyond five years, among their patients who underwent stereotactic body radiation therapy (SBRT) for node-negative early stage NSCLC many years earlier (see Dr. Loiselle’s great summary of SBRT for a review of the topic). Many Japanese centers have been pioneers in SBRT, doing it for more than a decade, but over the past 3-5 years the strategy has become far more widely practiced, based on very encouraging local control and outcomes going out several years, which lead to the question of whether SBRT might be an effective and alternative to surgery (hence the keen interest among thoracic surgeons about whether newer radiation techniques will lead to reduced demand for their services). The authors of this report, who are radiation oncologists, highlight that it’s possible we’ll see late recurrences beyond the time when we’d be inclined to declare a victory for SBRT. In general, if we see patients doing well 3-5 years after diagnosis and the start of treatment, we begin to think we’re getting out of the woods.
The longer-term outcomes for a total of 66 patients who had undergone SBRT for node negative NSCLC between 1999 and 2005 were reviewed, though the median follow-up was only three years. Given the fact that these treatments were done 6-12 years ago, this median reflects that many people were lost to follow-up or died in the first few years. As is typical for retrospective reviews of patients who underwent radiation for potentially resectable NSCLC, many of the patients who died (14 of 39) had other significant medical problems had no evidence of active cancer at the time of their death. Sixteen patients remained alive and without evidence of disease beyond five years from the time of SBRT, and the authors noted that four of them (25%) had recurrences beyond that point — in fact, three of the four had recurrences more than eight years after treatment. In three of the four cases, the recurrences were local (one patient had both local and distant recurrence in another part of the body). Past history with surgery for early stage NSCLC has generally shown that the risk of recurrence beyond 5 years is in the range of 5-7%.
This isn’t a large series of patients, and it’s the experience from just a single (well experienced) center. They also note that the dose used (48 Gray (Gy) over 4 treatments is less than the 60 Gy over three fractions that is often used in some places now, so results could be different with these different techniques. Of course, no local treatment — neither excellent surgery nor the best radiation therapy — will cure disease that is destined to recur distantly from micrometastatic disease outside of the local area visible on scans. But the promise of SBRT, of providing comparable long-term local disease control and perhaps working as effectively as the historical gold standard of surgery, still awaits a test of time to really clarify whether it looks very favorable beyond the first few years.
A few months ago, I had a patient in my clinic who is a lifelong never-smoker with an adenocarcinoma. I had her tumor checked for molecular markers, which revealed that she had both an activating EGFR mutation (exon 19 deletion) and a T790M mutation associated with resistance (see Dr. Pennell’s excellent summary for an introduction to EGFR mutations). Not sure what to expect from an EGFR tyrosine kinase inhibitor like Tarceva (erlotinib), I started her on chemo first, which she responded to for a while, and then put her on a Tarceva-based trial for second line. Though her cancer-related symptoms of cough and non-exertional chest pain improved significantly within just a few weeks, her scan actually showed a mixed response: dramatic improvement of her chest disease, but modest progression with new bone lesions.
We now have a little more information to help guide our expectations in this setting. A new publication in the Journal of Clinical Oncology from Su and colleagues from Taiwan provides several valuable new insights on T790M, the mutation that has been identified as the most common cause of acquired resistance to an EGFR tyrosine kinase inhibitor (TKI) after an initial good response in patients with an EGFR activating mutation The investigators looked for both activating mutations and T790M mutations in Taiwanese patients, predominantly (about 75%) never-smokers and >90% with an adenocarcinoma, both before (107 patients) and after EGFR TKI therapy (87 patients) using three different methods: typical DNA sequencing, MALDI-TOF, and next generation sequencing. For those who are really curious, extremely scientifically gifted, or very bored, this last link provides a good explanation of sequencing techniques, but this is really getting outside of the scope of what we need to know here; basically, direct gene sequencing is the usual mutation detection technique, MALDI-TOF is a less commonly used novel approach, and next generation sequencing is the “gold standard” that really clarifies who has what. Continue reading