What happened, in summary

An 89-year-old woman was diagnosed with Stage I adenocarcinoma of the left upper lung carrying an EGFR exon 19 deletion and underwent left upper lobectomy. About 1 year later, pleural biopsy confirmed recurrence and she started gefitinib. Three years later, an enlarged left axillary lymph node showed recurrent adenocarcinoma with the original EGFR alteration plus an acquired T790M mutation. She switched to osimertinib and achieved a partial response, although treatment required dose adjustment for thrombocytopenia. Recurrent organizing pneumonia also required corticosteroids and several treatment interruptions and restarts. About 3 years after starting osimertinib, she developed pulmonary tuberculosis. Because stopping targeted therapy raised concern for cancer progression, osimertinib was continued while tuberculosis was treated for 9 months. Her sputum cultures became negative, and imaging showed no progression of the axillary lesion or new abdominal or brain disease. Osimertinib continued to maintain a partial response. By the end of tuberculosis treatment, she was more than 7 years from her original lung-cancer diagnosis.