Bone marrow trephine biopsy involvement by lymphoma: pattern of involvement and concordance with flow cytometry, in 10 years from a single institution.

PURPOSE: To evaluate the features of bone marrow (BM) biopsy involvement by lymphoma, pattern of infiltration, morphological analysis and flow cytometry were reviewed at all lymphoma patients over a period of 10 years.

METHODS/PATIENTS: 413 cases were included in the study if BM biopsy slides were available. Only 356 patients had both BM trephine biopsy and flow cytometry.

RESULTS

The most frequent subtype was diffuse large B cell (31.2%), followed by follicular lymphoma (18.9%). The predominant pattern was mixed (nodular-interstitial) (9.2%). Morphological marrow infiltration was found in 138 cases, and flow cytometry identified 117 cases with BM involvement. A concordance between the two methods was detected in 305 cases (85.7%). There was discordance in 51 cases (14.3%): morphology positive/FC negative in 33 cases and morphology negative/FC positive in 18.

CONCLUSIONS

Flow cytometry is slightly more useful in detecting involvement when the BM is affected, but this finding is not conclusive.