Fig. 3

a A 44-year-old man diagnosed with metastatic malignant melanoma presented with a new metastasis measured 30 × 19 mm in diameter (circle) in the upper lobe of the left lung while under the temozolomide and cisplatin treatment. b, c In the first control performed after 12 weeks initiation of immunotherapy with nivolumab (anti-PD-1 monoclonal antibody), the lesion in the left lung was almost regressed (circle), but there was a new bone metastasis measured 15 × 13 mm in diameter in the sacrum (arrow). d-f In the second control performed after 16 weeks, the lesion in the left lung was regressed entirely (circle). Many new metastases were detected in the liver, spleen, and sacrum, measured 59 × 54 mm, 29 × 21 mm, and 20 × 10 mm in diameters, respectively (arrows)