Paraneoplastic disorders usually arise from a tumor secreting hormones, peptides, or cytokines affecting other tissue sites .
It can affect diverse organ systems, most notably the endocrine, neurologic, dermatologic, rheumatologic, and hematologic systems. The most common malignancy to be found includes small cell lung cancer
, breast cancer
, and hematologic malignancies. Treatments includes removal of the primary tumor and immunosuppression
for neurologic, dermatologic, and rheumatologic syndromes.