Solitary acrometastasis of the phalanx as initial presentation of an oligometastatic Kirsten rat sarcoma viral oncogene homolog-mutated lung adenocarcinoma: a case report

Background Acrometastasis is an uncommon finding in non-small cell lung cancer and is usually a sign of multimetastatic disease.

Few case reports have suggested solitary digital metastasis as the single secondary lesion of oligometastatic non-small cell lung cancer.

Case presentation This case report describes an unusual presentation of a Kirsten rat sarcoma viral oncogene homolog-mutated lung adenocarcinoma with a solitary bone metastasis in the fourth finger medial phalanx, which was also the first sign of the disease, in a 63-year-old Caucasian female patient.

Digital surgical amputation was performed.

After histopathological confirmation and radiological exclusion of other secondary lesions, chemoimmunotherapy in a first-line setting was initiated.

A partial metabolic response in the primary lung lesion was observed after four cycles.

Maintenance therapy is currently being continued.

Conclusion Solitary digital metastasis is a rare finding in non-small cell lung cancer.

Further studies are needed to investigate the mechanisms behind this particular dissemination process.