MET-mutated lung cancer: testing savolitinib before surgery — Case 2

What happened, in summary

A 66-year-old woman developed a cough with bloody sputum. CT showed a 5.4 x 3.0 cm mass in the right upper lung. Needle biopsy confirmed lung adenocarcinoma. Testing found a MET exon 14 skipping mutation and high PD-L1 expression of 75%.

The cancer was Stage IIIA, cT3N1M0. She first received 2 cycles of nedaplatin and pemetrexed, but the tumor did not shrink enough to make surgery straightforward.

Treatment changed to savolitinib 600 mg once daily. She developed dizziness and vomiting. Brain imaging did not show metastases, and the symptoms resolved after the savolitinib dose was reduced to 400 mg daily.

After 7 months of savolitinib, the lung tumor had shrunk by about 72% and the response remained stable. She then underwent video-assisted right upper lobectomy with systematic lymph-node dissection. Pathology showed that about 30% of the tumor remained viable, while all sampled lymph nodes were negative. The postoperative stage was ypT1bN0M0, Stage IA2.

She recovered without surgical complications and left hospital on postoperative day 5. Savolitinib 400 mg daily continued after surgery, without a new severe adverse effect.

Savolitinib created an opportunity for surgery after 2 chemotherapy cycles had produced little shrinkage. Reducing the dose controlled dizziness and vomiting without losing the tumor response. Pathology showed no involved lymph nodes and a much smaller residual primary tumor. She remained in postoperative follow-up while continuing savolitinib 400 mg daily, without a new severe adverse effect.