Metastatic Melanoma to Bone: A Clinicopathological Study of 236 Cases
David L Stockman, Alexandar J Lazar, Wei-Lien Wang. MD Anderson Cancer Center, Houston, TX
Background: Metastatic melanoma to bone is uncommon. It can be a source of diagnostic confusion in the differential of poorly differentiated malignant bone tumors. The 10-year experience of metastatic melanoma involving bone at a major cancer center was examined.
Design: The pathology files were reviewed from 2002-2012 for metastatic melanoma involving bone in center where over 9060 patients with primary melanomas was seen. Cases of direct extension originating in the skin and soft tissue were excluded. Clinical and radiological studies were reviewed.
Results: Two hundred thirty six cases were identified. The median age was 53 (range, 24 to 83) yrs with a male to female ratio of 141:95. Sites of involvement include the vertebrae 27%(64/236), pelvis 21%(49/236), femur 17%(40/236), sacrum 14%(34/236), humerus 9%(20/236), rib 5%(11/236), fibula 4%(10/236), and skull 3%(8/236). In 97%(229/236) of cases, patients had multiple metastasis and 89%(194/217) were radiographic lytic lesions. The mean time from primary tumor diagnosis to bone metastasis was 148(range, 0-320)mo. Location of primary melanomas included head and neck 29%(68/236), back 25%(59/236), shoulder 16%(38/236), mucosal 5%(12/236), thigh 4%(10/236), upper extremity 4%(10/236), abdomen 2%(5/236), elbow 0.4%(1/236), and unknown 14%(33/236). Primary melanoma types included nodular melanoma 54%(128/236), superficial spreading 31%(74/236), lentigo maligna 7%(18/236) acral lentiginous 3.4% (8/236), and mucosal 3.4% (8/236). Clinical outcome was available in 230/236 patients(median, 49 mo, range:1-1364 mo): 148/230 (64%) died of disease, 82/230 (36%) were alive with disease and six patients were lost to follow up. The median time to death after diagnosis was 81 (range:7-1364) mo, after first metastasis 28 (range:1-134)mo, and after first bone metastasis was 12(range:1-40) mo. Significant differences in outcome survival were identified based on general metastatic location (best to worst OS, long bones, vertebrae, pelvis, thoracic, skull, p<0.001). No significant difference was observed among primary melanoma subtypes (p=0.124).
Conclusions: This is the largest series of metastatic melanoma to bone. Metastatic melanoma to the bone is uncommon (3%) and can be the first site of metastases for patients. Bone metastases herald a poor prognosis and site may be prognostically significant. Nodular melanoma was the most common histologic subtype with the back being the most common location of primary origin.
Category: Bone & Soft Tissue
Tuesday, March 5, 2013 1:00 PM
Poster Session IV # 15, Tuesday Afternoon