Co-incidental presentation of IgA lambda multiple myeloma and pleural involvement with IgM kappa non-Hodgkin's lymphoma.

Pleural effusions occur in approximately 6% of patients with myeloma. The aetiology is multifactorial and effusions due to pleural myelomatous involvement are rare, occurring in < 1% of cases. We report the case of a 68-year-old lady who presented with IgA myeloma and a concurrent pleural effusion due to a second IgM kappa producing B cell neoplasm. The former responded but the latter was resistant to standard myeloma therapy.