Spontaneous regression of small cell lung cancer combined with cancer associated retinopathy

• SR was observed in SCLC combined with cancer associated retinopathy (CAR).
• Recoverin antigen on the tumor cells and anti-recoverin antibody in the patient's serum was present.
• Activation of recoverin-specific CTL was found.
• SCLC was considered to reduce spontaneously by the immunologic reaction.
• This is the first report of SR in SCLC combined with CAR.

Spontaneous regression (SR) is defined as the complete or partial disappearance of disease without anticancer treatments. We report a case of SR of small cell lung cancer (SCLC) combined with cancer associated retinopathy (CAR). A 65-year-old woman was admitted to our hospital to examine abnormal shadows of the lung with visual loss. She was diagnosed with SCLC associated with CAR. Subsequent chest X-ray and CT scan showed partial regression of both primary tumor and lymph node metastasis without anticancer treatment. Recoverin antigen was present on the tumor cells and anti-recoverin antibody was observed in the patient's serum. Activation of recoverin-specific antitumor cytotoxic T lymphocyte (CTL) was observed in this patient. SCLC was considered to reduce spontaneously by the activation of recoverin-specific antitumor CTL. To the best of our knowledge, this is the first report of SR in SCLC combined with CAR.