Utilization of a human tumor cloning system to monitor for bone marrow involvement in children with non-hodgkin's lymphoma.

The objective of this study was to evaluate the sensitivity of two methods for determining bone marrow involvement with non-Hodgkin's lymphoma. These methods were histologic review of bone marrow aspirates, and clot sections versus in vitro growth of lymphoma colonies on soft agar. Forty-two bone marrow aspirates were studied from 14 children who were without bone marrow involvement at diagnosis. There were seven bone marrow aspirates (from five patients) that had histologic evidence of metastatic lymphoma. Six of these seven specimens formed colonies in vitro. Twenty-nine of 35 histologically negative specimens showed no lymphoma colony growth. However, six histologically negative specimens (from three patients) formed lymphoma colonies. Both the Fisher's exact test and the K statistic were significant, indicating not only an association between histology and in vitro culture results, but also a close agreement. In addition, growth of lymphoma colonies in vitro was associated statistically with both a short duration of complete remission and a short duration of survival.