I would like to ask a question about my mums progressions to make sure that my reasoning about my mother’s progression is OK :
My mother (73) was diagnosed with NSCLC IV.stage in April 2016 extensive tumor in both lungs (main tumour and many small/tiny lesions) and mediastinum, without distant methastases, only in lymph nodes) - EGFR positive –mutation exon 18- G719X - more info here : https://www.inspire.com/m/daxys/
She was for 21 months on Afatinib (40% tumour reduction), which was stopped after only slight and slow progression (only three lung metastases grew by 1-2,5 mm). Then she had 3 infusions of pemetrexed within 2 months and after that she was for 1,5 month without any treatment for lungs. In these 3,5 months (pemetrexed and no treatment) she had 50% growth of the tumor (main tumor grew from 32x17 to 40x23 mm).
After that she was on osimertinib for almost 2 months – CT showed that everything was stable after 2 months on osimertinib except for 2 lesions in lungs (which grew from 6 to 10 mm and 11 to 15 mm). Despite the fact that osimertinib stopped overall progression, the oncologist stopped it and started carboplatin monotherapy. After 3 weeks of no treatment and 3 weeks with one infusion of Carboplatin a major overall progression was shown on an X-Ray scan (some lesions by 100%).
To me it seems obvious that the original mutation ex.18-G719X was and still is responsible for the most of the growth we have had. G719X was detected in the liquid biopsy in June 2018 (the only mutation detected). The overall growth always happened when we stopped blocking it by afatinib and later by osimertinib (osimertinib was tried despite T790M was not detected and she is probably T790M negative). The progression on osimertinib was limited and happened in different lesions than the progression on Ist line afatinib. I also think that our time on osimertinib was quite short for other progression mechanisms to develop.
Could I please ask someone whether there is anything wrong about my explanation of my mums progression and ex.18-G719X being responsible for the most of it ?