Rheumatic manifestations of primary and metastatic bone tumors and paraneoplastic bone disease.

Bone tumors can show a wide range of nonspecific rheumatic manifestations. The presence of unexplained or atypical chronic bone pain, an enlarging bone mass, neurovascular compression syndromes, or pathologic fractures should alert us to the possibility of a bone tumor causing these symptoms. These patients must undergo a complete physical examination; adequate imaging; and, if needed, a biopsy to confirm their diagnosis and offer them an opportune treatment. In addition, bone tumors and other malignancies can present remote clinical manifestations and unusual laboratory findings (eg, HOA, hypophosphatemia, hyperphosphaturia, and hypercalcemia) that may be the first and early manifestation of an occult cancer. These findings should motivate a cancer screening according to age, sex, and personal history. Cancer therapies also have a big impact on bone health, increasing the risk of osteoporosis, osteomalacia, and/or osteonecrosis. Rheumatologists should be aware of possible long-term adverse events of cancer treatment to avoid future complications.