Name

Extraosseous plasmacytoma

ICD-O-1 Morphology

9731/3: Solitary plasmactyoma of bone
Effective 1978 - 1991

ICD-O-2 Morphology

9731/3: Solitary plasmactyoma of bone
Effective 1992 - 2000

ICD-O-3 Morphology

Effective 2001 and later

Reportable

for cases diagnosed 1978 and later

Primary Site(s)

See Module 7
Primary site cannot be bone (C400-419). Most common sites of involvement: upper respiratory tract (80%), oropharynx, nasopharynx, sinuses, larynx, gastrointestinal tract, lymph nodes, bladder, CNS, breast, thyroid, testis, parotid gland, and skin

Abstractor Notes

This is a localized solitary tumor in sites other than the bone consisting of monoclonal plasma cells. Complete skeletal radiographs (preferably MRI) show no other lesions. If additional lesions are found on MRI or CT (or other radiological surveys), this is diagnostic of plasma cell myeloma (see 9732/3).

Do not code primary site to C40._ or C41._. These category codes should only be used with histology 9731/3.

FISH and immunophenotyping help to differentiate these lesions from MALT and Marginal zone lymphomas.

Diagnostic Confirmation

This histology can be determined by positive histology (including peripheral blood) with or without genetics and/or immunophenotyping. Review the Definitive Diagnostic Methods, Immunophenotyping and Genetics Data sections below, and the instructions in the Hematopoietic Manual for further guidance on assigning Diagnostic confirmation.

Grade

Not Applicable

Module Rule

Module 2: PH2

Alternate Names

EMP
Plasmacytoma, extramedullary
Plasmacytoma, NOS (occurring outside of bone)
Solitary plasmacytoma (occurring outside of bone)

Definition

Solitary plasmacytomas are single localized tumors consisting of monoclonal plasma cells with no clinical features of plasma cell myeloma (PCM)(see 9732/3) and no physical or radiological evidence of additional plasma cell tumors.

Extraosseous (extramedullary) plasmacytomas are localized plasma cell neoplasms that arise in tissues other than bone. They occur most commonly in the mucous membranes of the upper air passages, but they can also occur in numerous other sites, including the gastrointestinal tract, lymph nodes, bladder, breasts, thyroid, testes, parotid glands, skin and CNS.

Plasmacytomas of the upper respiratory tract spread to cervical lymph nodes in about 15% of cases.

Definitive Diagnostic Methods

FISH
Genetic testing
Histologic confirmation
Immunophenotyping

Genetics Data

t(11;14)(q13;q32) (IGH.CCNDI) lacking

Immunophenotyping

C19+ (expression/positive)
CD20+ (expression/positive)
CD45+ (expression/positive)
CD56+ (expression/positive)
Cyclin DI (usually lacking)

Treatments

Chemotherapy
Radiation therapy
Surgery

Transformations to

Transformations from

None

Same Primaries

Corresponding ICD-9 Codes

203.8 Other immunoproliferative neoplasms
238.6 Plasma cells

Corresponding ICD-10 Codes

C90.2 Plasmacytoma, extramedullary

Corresponding ICD-10-CM Codes (U.S. only)

C90.2 Extramedullary plasmacytoma (effective October 01, 2015)

Signs and Symptoms

Epistaxis
Presence of M-protein, most commonly IgA (~20% of patients)
Rhinorrhea

Diagnostic Exams

Blood and urine immunoglobulin studies
Blood chemistry studies
Cytogenetic analysis
Skeletal survey
Tissue biopsy
Twenty-four-hour urine test

Progression and Transformation

Regional recurrences occur in ~25% of patients
Occasionally metastasis to distant extraosseous sites
Transformation to plasma cell myeloma occurs in ~15% of cases

Epidemiology and Mortality

Age: 55 years median age
Incidence: 3-5% of plasma cell neoplasms
Sex: male predominance
Survival: ~70% of patients remain disease free at 10 years

Sources

Swerdlow SH, Campo E, Harris NL, Jaffe ES, Pileri SA, Stein H, Thiele J (Eds):
WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues (Revised 4th edition)
IARC: Lyon 2017
Section: Mature B-cell neoplasms
Pages: 251-253

International Classification of Diseases for Oncology, Third Edition, Second Revision. Geneva: World Health Organization, 2020.
Section: ICD-O-3.2 (2020) Morphological Codes
Pages: http://www.iacr.com.fr/index.php?option=com_content&view=category&layout=blog&id=100&Itemid=577

National Cancer Institute
Section: General Information About Plasma Cell Neoplasms
Pages: https://www.cancer.gov/types/myeloma/hp/myeloma-treatment-pdq
Glossary