This is week #9 on clinical study, as I received my infusion of M7824 yesterday as planned. All of my pre-therapy vitals and bloodwork came back fine, which meant the treatment was a go. As with previous infusions, there were no issues during or after. Everything went just fine.
It was unfortunately a later night than expected, as Lorie and I just missed our 7:30pm train and had to catch one leaving the next hour. So, we ended up walking in the door at home around midnight. Could always be worse!
Following the discussion in my past few blog posts, I’ve been learning more about the concept of “pseudoprogression,” or the apparent growth of a tumor followed by sustained regression, which is common following treatment with checkpoint inhibitors. For example, I came across the video clip below by OncLiveTV that contains a discussion of “Pseudoprogression With Checkpoint Inhibitors in Non-Small Cell Lung Cancer,” where panelists explore the implications of this phenomenon for patients with NSCLC. While I do not have NSCLC, the overall concept of pseudoprogression with checkpoint inhibitors is relevant to my treatment and latest scan results – whereby the tumor growth exhibited could be from inflammation due to an ongoing positive immune response, or from an actual increase in the tumor that continues until the body’s immune system overpowers the cancer. It could also be a combination of the aforementioned. In any event, I think that pseudoprogression is an important concept for patients receiving some immunotherapies to better understand – especially when getting imaging results following treatment.
PS – anyone who knows me, knows that I’m a big Chicago Cubs baseball fan (having grown up in Chicago)…so I’d be remiss if I didn’t ask you to keep voting for retired catcher David Ross on this season’s ‘Dancing with the Stars’. In case you missed his debut performance, here’s a clip where he danced to Steve Goodman’s “Go Cubs Go” – while wearing Cubs gear.
As evidenced by the extensive discussions following my biopsy from last Friday, a tumor is indeed a very complex structure. It comprises cancer cells and stromal cells, tumor infiltrating cells—both cells of the immune system and cells not by convention being of the immune system, as well as an extracellular matrix mainly of proteins and carbohydrates.
Following my recent CT scan, the hope from obtaining core biopsies from one of my lung nodules was to get a better sense of the cancer at a cellular level, which may help shed some light on whether or not treatment with M7824, a completely novel, first-in-class, bispecific fusion protein is working (see prior posts for more details).
In particular, the presence of immune system cells (T cells, or T lymphocytes) in tumor biopsies and their potential impact on prognosis have been studied for decades. T cells are a type of white blood cell that circulate around our bodies, scanning for cellular abnormalities and infections. Broadly speaking they can be divided into two different types, “killer” CD8-positive T-cells and “helper” CD4-positive T-cells. CD8-positive T cells are critical mediators of adaptive immunity. They include cytotoxic T cells, which are important for killing cancerous or virally infected cells, and CD8-positive suppressor T cells, which restrain certain types of immune response.
Despite contributions by other immune cell subsets, CD8-positive T cells have emerged as the predominant effector in most cancer immunotherapy settings¹. Accordingly, many immunotherapeutic strategies (including checkpoint inhibitors, such as anti-CTLA4, PD1, and PD-L1 antibodies) are dedicated to stimulating, enhancing and maintaining responses by tumor-reactive CD8-positive T-cells.
Favorable outcomes have been demonstrated in patients where high numbers of CD8-positive cells were found at the tumor site in patients with head and neck cancer, breast, colorectal cancer and also for others solid cancers. In one study, head and neck cancer patients whose tumors were densely infiltrated by CD3-positive and CD8-positive T cells had a significantly longer overall survival (OS) and progression-free survival (PFS) compared with patients whose tumors were poorly infiltrated².
While there seems to be a consensus that CD8 infiltration is a good prognostic marker in most malignancies analyzed, however, the impact of CD8-positive T cells on clinical outcome may differ and is difficult to quantify. Not only is the type of T cell important, but also its location, and moreover the specific phenotype and function of those cells in the particular environment.
Nonetheless, based on the preliminary results from my recent tumor biopsy and other factors, it appears that there is sufficient evidence of immune system activation in the vicinity of the tumor to indicate that the experimental agent M7824 may indeed be performing as we hoped. Accordingly, I am in 100% agreement with my doctor’s recommendation to continue on the therapy and will receive my next infusion this coming Tuesday at NIH. After a few more cycles of therapy, another CT scan will be taken in the future with the hope of demonstrating that the recent tumor growth was from treatment effect “pseudo-progression” rather than true disease progression, which has been previously described with immune checkpoint inhibitors like M7824.
¹ Targeting CD8+ T-cell tolerance for cancer immunotherapy. Stephanie R Jackson, Jinyun Yuan, and Ryan M Teague. Immunotherapy. 2014 Jul; 6(7): 833–852.
² Tumour-infiltrating lymphocytes predict response to definitive chemoradiotherapy in head and neck cancer. P Balermpas, Y Michel, J Wagenblast, O Seitz, C Weiss, F Rödel, C Rödel and E Fokas. British Journal of Cancer (2014) 110, 501–509. doi:10.1038/bjc.2013.640
Following Tuesday’s news that several of the tumors in my lungs actually increased in size and a new spot appeared on my spleen, Lorie and I headed back to the NIH on Thursday for more tests to help better guide subsequent treatment decisions.
The first test was a CT image of my brain taken Thursday mid-afternoon, which would be used to rule out the spread of cancer to that particular organ. Patients with brain metastases are often excluded from clinical trials due to historically dismal survival and concerns about blood brain barrier drug penetration. Fortunately, we learned the next morning that this test came back negative for cancer progression to the brain.
The second test on Friday was an image-guided biopsy of a single lung nodule to help guide between cancer progression and inflammation as the reason for the increase in size seen on the recent CT scan on the lungs. In my case, a core needle biopsy was performed, which is less invasive than surgical biopsy and doesn’t require general anesthesia.
Early Friday morning, Dr. Elliot Levy, an interventional radiologists at NIH trained in radiology and minimally invasive procedures, met with us first to discuss the procedure. He pulled up a cross sectional image of my lungs, which showed several of the suspicious nodules.
One in particular was located in the pleural cavity – normally a thin membrane that lines the surface of the lungs and the inside of the chest wall outside the lungs. In the bottom of my left lung, however, fluid built up in the pleural cavity where one of the nodules was located. Dr. Levy explained to us how this nodule could be biopsied without puncturing the lung lobe, which can result in a longer hospital stay.
Sometimes, a collapsed lung (pneumothorax) occurs after a lung biopsy. As a precaution, a chest x-ray is taken after the procedure to check for this before sending the patient home.
After meeting with Dr. Levy, I was escorted back to the biopsy procedure room and placed on my right side on a table. I was consciously sedated, produced by the administration of two medications: a single dose of fentanyl given intravenously that can produce good analgesia for 20-45 minutes, and midazolam, which has a fast-acting, short-lived sedative effect when given intravenously, achieving sedation within one to five minutes and peaking within 30 minutes. The combination produces an altered level of consciousness that still allows a patient to respond to physical stimulation and verbal commands, and to maintain an unassisted airway. Midazolam is a primary choice for conscious sedation because it causes patients to have no recollection of the medical procedure.
Dr. Levy worked out of sight behind me to perform the biopsy, as he went through my back side. I was fairly nervous going into the procedure, but everything went extremely well with absolutely no pain or unexpected events due to the sedation.
After recovery, a subsequent chest x-ray confirmed that the lungs were indeed fine after the biopsy and we left NIH shortly thereafter to head back home to Pennsylvania.
The preliminary results from the biopsy should be available early this week. If the biopsy shows ample evidence of immune stimulation, an argument could be made to stay on the current drug and that the “pseudoprogression,” or the initial radiologic appearance of an increase in tumor burden, might actually be inflammation and followed by tumor regression. A remote possibility in my type of cancer, but worth confirming.
Should the biopsy results instead demonstrate increased tumor burden, then we could consider switching to another investigational agent or even chemotherapy to shrink the tumors before proceeding again with one of the immunotherapy clinical trials.
Determined to stay positive, Lorie and I took advantage of the warm spring day on Thursday to stop outside NIH and snap a picture in front of some cherry blossoms. Unfortunately, snow and cold returned on Friday for the commute home.
The results of today’s CT imaging procedure were not as we had hoped. Ideally, the dozen or so tumors in my lungs would have shown signs of shrinkage – indicating that the investigational drug was having a positive effect on the cancer. Instead, several of the tumors actually increased in size and a new spot even appeared in my spleen.
One of the hallmarks of immunotherapy, such as the checkpoint inhibitors, is the potential for a “delayed” response, which is not routinely seen with chemotherapy or other cytotoxic agents. Another biologic phenomenon unique to immunotherapy is “pseudoprogression,” or the initial radiologic appearance of an increase in tumor burden subsequently followed by tumor regression¹.
The CT imaging study cannot distinguish between cancer progression or inflammation as the reason for the increase in tumor size, so there is a chance that it’s due to inflammation and subsequent imaging tests in a month could demonstrate a reversal. However, it is also possible that the cancer isn’t responding to the investigational treatment.
To get more details, I’m undergoing a biopsy this Friday so that one of the lung tumors can be sampled. The preliminary information from that biopsy, which should be available next week, will help guide between cancer progression and inflammation. Decisions regarding how to proceed will depend on that outcome.
Needless to say, everyone’s hope was to have seen some sign of cancer regression on today’s CT scan and many teardrops were shed. The chances for a favorable outcome have diminished and must be acknowledged, but for now I’m persevering and will evaluate next steps following the biopsy results.
Sincere thanks to everyone who has offered their positive thoughts, prayers, and support. It is difficult to respond to each and every communication, but please know that I read “everything” and your time and effort is greatly appreciated. Special thanks to everyone at NIH for being so wonderful — even when faced with delivering bad news.
Now, more than ever, please keep all those positive vibes coming my way.
¹ Amidst the excitement: A cautionary tale of immunotherapy, pseudoprogression and head and neck squamous cell carcinoma. Baxi SS, Dunn LA, Burtness BA.
Oral Oncol. 2016 Nov;62:147-148. doi: 10.1016/j.oraloncology.2016.10.007. Epub 2016 Oct 21.