Rapidly progressive squamous cell lung cancer with MET exon 14 skipping mutation metastasized to atypical bone sites - a case report.

BACKGROUND

The mesenchymal-epithelial transition factor (MET) exon 14 skipping mutation has recently emerged as a driver gene in non-small cell lung cancer (NSCLC) in clinical practice. Clinical trials of several MET inhibitors have shown the effectiveness of MET inhibitors in NSCLC patients with MET exon 14 skipping mutation. To the best of our knowledge, however, there was no patient with sole MET exon 14 skipping mutation who progressed rapidly and had a poor prognosis.

CASE: A 61-year-old man presented with pain in the dorsum of the left foot and in the left elbow. Chest CT revealed a mass in the right lower lobe of the lung, and FDG-PET showed metastases in the ribs, thoracic vertebra, left elbow, and left metacarpal bone. Corrected calcium level was elevated up to 14.1mg/dL. The histopathology of the transbronchial bio-psy specimen was morphologically consistent with squamous cell carcinoma. MET exon 14 skipping mutation was positive in Oncomine Dx Target Test Multi-CDx system. Within a few weeks of admission, the patients respiratory condition rapidly deteriorated carcinomatous lymphangiosis and died of acute respiratory failure one month after admission. In this patient, bone metastases to atypical sites and hypercalcemia were also observed.

CONCLUSION

Chest physicians should be noted that there might be rapidly progressive fatal patients among those with MET exon 14 skipping mutations.