Rationale:
Malignant melanoma with indiscoverable skin manifestations is unusual and refractory hypercalcemia with high metabolic signal of the rectum as initial manifestation is very rare.
Patient concerns:
We present a case that presented with paresis, nausea, and vomiting.
Diagnoses:
Malignant melanoma with spinal metastasis.
Interventions and outcomes:
The patient underwent posterior decompression, partial tumor resection, bone cement reconstruction, and internal fixation. The patient's hypercalcemia was controlled and muscle strength was partially recovered. The immunohistochemical stainings showed Melan-A (+), HMB45 (+), s-100 (+), Vimentin (+), and AE1/AE3 (−).
Lessons:
We emphasize the necessity of screening potential existence of neoplasms for the patients with hypercalcemia. Surgical treatment is still necessary for patients with spinal metastasis.