8;14 chromosome translocation in a negative bone marrow aspirate from a patient with Burkitt's lymphoma

Chromosomal abnormalities in adult non-endemic Burkitt's lymphoma and leukemia: 22 new reports and a review of 148 cases from the literature

Tumour cell karyotypes from patients with Burkitt lymphoma (BL) or Burkitt's type leukemia (ALL3) were studied for correlation with survival, bone marrow and cerebral spinal fluid involvement (CSF), human immunodeficiency virus (HIV) serology, and for recurrent cytogenetic abnormalities. The records of 22 patients with BL from our institution and of 148 cases of BL and ALL3 reported in the literature with karyotypes were evaluated for clinical and cytological features. Overall survival was only 28 per cent and 88 per cent of deaths occurred within the first nine months after diagnosis. Those who survived at least 18 months were unlikely to relapse. Age and gender did not significantly affect survival. Patients presenting with advanced Ann Arbor stage, bone marrow or CSF involvement had lower survival rates. The association of translocations involving chromosome band 8q24 with this disease is confirmed. Sixty-two per cent of karyotypes had t(8;14)(q24;q32) translocations; the recognized variant translocations t(8;22)(q24;q11) and t(2;8)(p12;q24) affected 12 per cent and 9 per cent respectively. Seventeen per cent had abnormal karyotypes but no classic translocation. Patients with variant translocations had the poorest survival rates, and those with the classic t(8;14)(q24;q32) did the best. Despite a small sample size, the variant translocation t(8;22)(q24;q11) appeared to occur at an increased frequency in the patients with AIDS. In the entire group, recurrent involvement of chromosome regions 1q2, 6q11-14 and 17p1 suggests that alteration of genes at these loci, B Cell Growth Factor (BCGF) at 1q2 and p53 on 17p, may contribute to the development and progression of this tumour. Similarly, the frequent trisomies of chromosomes 7, 8, 12 and 18 may indicate an effect on tumour cell growth due to increased gene dosage. Trisomy 12 was found in eight tumours, five from patients with AIDS, suggesting that chromosome 12 has a site or gene whose allelic dosage is selected for in AIDS related lymphoma cells. Cytogenetic studies of adult Burkitt lymphoma and leukemia suggest several likely loci for gene alterations that in conjunction with myc translocations can lead to tumorigenesis.

An immunocytochemical study of lymphocyte and macrophage populations in the bone marrow of patients with non-Hodgkin's lymphoma

Pairs of bone marrow trephine samples from 67 patients with known or suspected non-Hodgkin's lymphoma (NHL) were collected. One sample was processed for morphological examination, the other for frozen section immunohistology, using a panel of monoclonal antibodies (MAB) reacting with lymphocyte and macrophage determinants, detected by the immuno-alkaline-phosphatase (APAAP) method. Forty-one cases showed definite (36) or suspected (5) involvement of the marrow by NHL. Most were examples of lymphocytic or centroblastic/centrocytic NHL. The pattern of immunostaining confirmed the presence of NHL in these cases: the phenotype of the neoplastic cells was broadly consistent with nodal histology, where available. In ten cases, the marrow showed no evidence of involvement by NHL, and in 15, the eventual diagnosis was an abnormality of the myeloid series. These two groups of marrows not involved by NHL both showed a 'reactive' pattern of immunostaining, comprising polyclonal B-cells, T-helper and suppressor/cytotoxic cells and macrophages. We conclude that immunohistological examination of the bone marrow is useful in cases where the specimen shows morphological evidence of NHL, including those that are only 'suspect', but does not detect lymphoma where there is no morphological evidence of involvement.

Preferential in-vitro growth and expansion of leukemic T lymphoblasts

An in-vitro culture system was used to selectively grow malignant cells from the bone marrow of a patient with acute T-lymphoblastic leukemia. Molecular analysis of DNA extracted from the bone marrow cells before culture showed the presence of both rearranged and germ line patterns for the T-cell beta receptor (CTB) gene, and chromosomal analysis revealed the presence of a major and a minor abnormal clone. The cells were cultured in RPMI medium supplemented with 20% fetal calf serum, 2% lymphocyte conditioned medium, L-glutamine and antibiotics. The presence of malignant cells in the cultured population was confirmed by morphologic, molecular probing and cytogenetic analysis. After four weeks in culture, DNA extracted from the cultured cells showed only the rearranged pattern for the CTB gene. Chromosomal analysis of the same cultured sample revealed only the presence of the initially predominant abnormal clone. Shortly thereafter, analysis of fresh uncultured bone marrow cells from the patient in relapse revealed that the same chromosomally abnormal clone also predominated in vivo. Thus, our results demonstrate the selective nature of this culture system and its ability to amplify leukemic T-lymphoblasts. This culture system is also useful for detecting occult malignant cells in histologically normal bone marrow.

Cytogenetic evaluation of bone marrow involvement in Burkitt's lymphoma

Twenty-six bone marrow samples from 21 patients with Burkitt's lymphoma were examined cytogenetically after short-term culture. Clonal chromosomal changes were detected in one of 18 samples from morphologically normal marrows, and in three out of six samples with verified tumor invasion. Three patients had the translocation (8;14)(q24;q32) and one had t(2;8)(p12;q24). Two samples with suspect tumor involvement (less than 5% putative tumor cells) showed no clonal abnormalities. In two samples without morphologic bone marrow infiltration and with only normal metaphases in short-term cultures, clones with t(8;14)(q24;q32) were revealed after a longer time (3-12 weeks) spent in vitro.