Rheumatic manifestations in malignancy

The association between malignancy and rheumatic diseases is complex and many factors contribute to it. Malignancies may lead to rheumatic manifestations either directly by invasion or metastases, or indirectly by remote para-neoplastic effects. Chemotherapeutic agents and bone marrow stimulatory biologic agents such as G-CSF and GM-CSF used in the treatment of malignant diseases may also result in rheumatic symptoms. While many of these rheumatic symptoms occur during the course of the malignant disease, often these rheumatic manifestations are the initial presenting features of a hidden malignancy or sometimes occur as late complications of them. Most of the cancer associated rheumatic disorders have no distinguishing features. As well, it is generally held that an extensive search for occult malignancy, beyond routine age-appropriate cancer screening, is not cost efficient and is not recommended unless accompanied by symptoms and signs suggestive of cancer. In this review, we identify rheumatic manifestations associated with malignancy and call attention to possible features that may suggest the presence of an occult malignancy. Awareness of these features may permit earlier diagnosis of the malignancy or its relapse.