Hi, I've been reading Cancer Grace for some time, but this is my first post. I would be grateful for any thoughts about this (my oncologist is away at the moment and any interpretations or comparisons much appreciated)!
(My question first; my history below)
Question: I have just had a CT scan which shows that my main lung cancer tumor has shrunk following the first two sessions of chemotherapy (from 2.5 x 2.4 cm to 2.1 x 1.4cm). However, bone metastases, particularly in lumbar region, seem to have progressed further. What does this mixed result likely mean? Would you say the chemotherapy is working or not really?
History: diagnosed with metastatic lung cancer in early October 2012; adenocarcinoma, KRAS mutation; 38-yr old female, never-smoker; treated with paliative radiation to cervical vertebrae where there was pain, followed by chemotherapy (carboplatin and permetrexed) and I have now completed 2 of 4-6 planned sessions of chemotherapy.
Reply # - December 26, 2012, 04:13 PM
Reply To: mixed result
Bone lesions are notoriously unreliable to read for progression vs. improvement, and that's why they aren't considered measurable disease on clinical trials. I strongly favor weighing the more measurable lesions as the key component and would only consider bone lesions as convincing for progression if [i]new[/i] ones appear.
There are certainly some situations in which we do see a truly mixed response of several lesions shrinking but others growing or a new lesion or two appearing. There's no rules for how to approach this situation. I favor making a judgment about which is the more dominant process, while also factoring in how well a person is tolerating the treatment and what further options remain, then making a decision of whether to continue with the present treatment or make a change. If you've just found out that the patient has an EGFR mutation and started with chemo, I'd favor a quick switch to EGFR inhibitor therapy at the first sign of progression; on the other hand, if you're seeing a mixed response to third line treatment and the person is tolerating the therapy very well, I would be far, far less inclined to discard that treatment.
Good luck.
-Dr. West
Reply # - December 26, 2012, 06:00 PM
Reply To: mixed result
Thanks very much, Dr. West.