Non-Hodgkin lymphoma involving the parotid gland: CT and MR imaging findings.

OBJECTIVES

As an uncommon neoplasm, parotid non-Hodgkin lymphoma (NHL) comprises mucosa-associated lymphoid tissue (MALT) and non-MALT lymphomas. Both types of lymphoma vary in prognosis and treatment. The aim of this study was to explore CT and MRI characteristics of these two types of lymphoma.

METHODS

61 cases of parotid NHL, 34 MALT and 27 non-MALT lymphomas with histopathological confirmation were examined with routine CT and MR scans prior to treatment, and retrospectively reviewed.

RESULTS

On CT and MRI, 34 MALT lymphomas presented with 11 solid and 23 solid-cystic forms, whereas 27 non-MALT lymphomas presented with 25 solid and 2 solid-cystic forms (p < 0.01).

CONCLUSIONS

Parotid MALT lymphoma is characterized mainly by the solid-cystic form, whereas non-MALT lymphoma is characterized mainly by the solid form. The differences on CT and MRI can offer helpful information for differentiation of both types of parotid NHL.