CT in malignancy grading and prognostic prediction of non-Hodgkin's lymphoma.

PURPOSE

The presence of tumor inhomogeneities in MR images of non-Hodgkin's lymphoma (NHL) provides information about malignancy grade and prognosis. The aim of this study was to determine whether CT images are also informative in these respects.

MATERIAL AND METHODS

Sixty-three CT examinations in patients with NHL (32 high-grade and 31 low-grade tumors) were reviewed retrospectively by two senior radiologists. The tumor patterns were classified subjectively as homogeneous, slightly inhomogeneous or severely inhomogeneous and their relations to malignancy grade, clinical characteristics and prognosis were determined.

RESULTS

Sixteen out of 17 patients with a severely inhomogeneous tumor pattern had high-grade NHL tumors while 21 out of 29 patients with a homogeneous tumor appearance had low-grade NHL tumors. Among chemotherapy-treated patients, those with the highest degree of inhomogeneity had a significantly worse prognosis (9 out of 11 patients died). This relationship was not found in patients treated with radiotherapy.

CONCLUSION

A severely inhomogeneous tumor pattern on CT images was found to be associated with a high malignancy grade in NHL. This CT pattern was also compatible with a poor prognosis in patients treated with chemotherapy.