An identical chromosome abnormality: der(6)t(6;7)(q13;p13) in two patients with peripheral T-cell lymphoma

A recurrent nonrandom translocation (3;7)(q27;p12) associated with BCL-6 gene rearrangement in B-cell diffuse large cell lymphoma

Two cases of B-cell diffuse large cell lymphoma associated with the t(3;7)(q27;p12) and BCL-6 rearrangement are described. Cytogenetic studies revealed [case 1] 47,XY,t(3;7)(q27;p12),+12 and [case 2] 45,X,-Y,t(3;7)(q27;p12),del(6)(q21q25),+16,-21. The translocation of each case had a non-random chromosomal change involving a 3q27 locus associated with BCL-6 gene rearrangement identified by Southern blot analysis. Both cases involved multiple lymph nodes and extranodal regions, such as stomach and peritoneal cavity in case 1, extranodal retroperitoneal space, subcutis, probable liver, and colon in case 2. Chemotherapy provided only short survival after onset: 17 and 16 months, respectively. Altered expression of adhesion molecules CD44, CD54 (case 1) and CD11a and CD18 (case 2) may help to explain the poor outcome of these patients.

Recurrent chromosome abnormalities in peripheral T-cell lymphomas

Cytogenetic findings in 45 cases of peripheral T-cell lymphomas (PTL) diagnosed according to the updated Kiel classification are reported. Recurrent numerical chromosome aberrations comprised -X, -Y, -13, +X, +3, +5 and +7. Recurrent structural aberrations included t/del(1)(p31-32), t(2;5)(p23;q35), dup(5)(q23q31-32), t/dup(6q), t/del(6q), trisomy 7q, and trisomy 8q, mostly due to i(8)(q10), and changes in 14q11 and 14q32.1, mostly due to inv(14)(q11q32.1), t/del(13)(q14), t(6;7)(q13;q13), and t(13;17)(q11-13;p11). All deletions in 6q involved band 6q21 and all partial trisomies of 7q led to an amplification of band 7q21. Further studies are needed to ascertain whether these cytogenetic findings in PTL are of clinical and prognostic significance.