SEER is an authoratitive source of information on cancer incidence and survival in the United States. SEER currently collects and publishes cancer incidence and survival data from population-based cancer registries covering approximately 28 percent of the U.S. population.
Plasma cell myeloma is a bone marrow-based multifocal plasma cell neoplasm. The disease spans a clinical spectrum from asymptomatic to aggressive forms, plus disorders caused by the deposition of abnormal immunoglobulin chains in tissue.
Plasma cell myeloma is a type of cancer of the plasma cells which are immune cells in bone marrow that produce antibodies.
The criterion for diagnosing plasma cell myeloma is usually equal to or greater than 10% of plasma cells in the bone marrow, but some symptomatic patients have a lower percentage. The registrar does not code plasma cell myeloma based on the percentage of plasma cells. There must be a diagnosis PCM.
A clinical diagnosis (no bone marrow biopsy done or unknown if bone marrow biopsy done) of PCM may be based on amyloidosis with associated renal impairment, anemia, and/or hypercalcemia supported by radiologic evidence of multiple lytic bone lesions.
Any case, including DCO's, listed as myeloma, multiple myeloma or PCM may be coded to 9732/3.
Multiple bone marrow biopsies may be done. Only one of the biopsies needs to be positive.
Plasma cell myeloma (PCM) usually has generalized bone marrow involvement. Lytic bone lesions and bone tumor masses of plasma cells also occur.
There are three clinical variants of plasma cell myeloma, all of which are coded to 9732/3.
Asymptomatic (smoldering or inactive) PCM: Bone marrow involvement, but no related organ or tissue impairment. Similar to MGUS in its lack of symptoms, but more likely to progress to symptomatic PCM. About 8% of patients are initially asymptomatic.
Non-secretory myeloma occurs when there is absence of an M protein on immunofixation electrophoresis; there is impaired (or not) secretion of immunoglobulin into the blood or urine. A bout 3% of PCM cases are non-secretory.
Plasma cell leukemia (PCL) occurs when the number of plasma cells in the peripheral blood is 20% of the leukocyte differential count. Other areas of involvement include spleen, liver, pleural effusions, ascites, and cerrebrospinal fluid. PCL may be present at diagnosis or occur as a late feature of PCM (secondary PCL); 2-5% of myeloma cases are primary PCL. Clinical features overall are similar to PCM. Lymphadenopathy, organomegaly and renal failure are often present in PCL. PCL is an aggressive disease with short survival.
Definitive Diagnostic Methods
Bone marrow aspiration
Bone marrow biopsy
Five major oncogenes involved in 14q32 translocation: cyclin D1, C-MAF, FGFR3/MMSET, cyclin D3, and MAFB
High load of IGHV gene somatic hypermutation
Immunoglobulin heavy and light chain genes are clonally rearranged
Whole or partial chromosome deletions or translocations