Favorable Survival of Multiple Myeloma Patients with t(11;14)(q13;q32) Plus Normal Chromosome 13q.

Previous studies have shown that specific chromosomal abnormalities are of major prognostic significance in patients with multiple myeloma (MM). It has been recently suggested that a t(11;14)(q13;q32) may be an indicator of favorable outcome in MM. In this investigation, we analyzed 163 patients with newly diagnosed MM (53% treated by high-dose therapy) to address the question whether or not the simultaneous occurrence of a t(11;14) and a deletion 13q [del(13q)], an established negative prognostic factor in MM, has any impact on prognosis. DNA-specific probes for IgH (14q32) and cyclin-D1 (11q13) were used for interphase FISH analysis of clonal plasma cells (cytoplasmic Ig positive). A t(11;14) by FISH was shown in 27 of the 163 MM patients (16.6%); the abnormality was present in the majority (median, 89%) of clonal plasma cells. Immunohistochemical analysis of CYCLIN-D1 expression was carried out in 72 patients, of whom 11 had a t(11;14) by FISH; all 11 patients had evidence for CYCLIN-D1 protein expression. Presence of a t(11;14) did not show significant correlations with standard laboratory and clinical MM features including type of the paraprotein, hemoglobin, creatinine, LDH, albumine, calcium, CRP, and beta-2-microglobulin (b2M). In contrast to a recent report, there was also no association with CD20 expression by MM cells. With respect to survival, presence of any 14q-translocation (52% of patients) was associated with similar overall survival times (OS) compared to patients lacking a t(14q), whereas patients with a t(11;14) experienced prolonged OS (median, 70+ months vs. 59.8 months among patients without t(11;14); P = .071). This survival advantage was even greater among the 16 patients with t(11;14) who were also normal for 13q (P = .02); however, occurrence of a del(13q) concomitantly with a t(11;14) was indicative for shortened progression-free survial (17.7 months vs. 31.6 months; P = .17) and OS (P = .07). A survival benefit of MM patients with a t(11;14) was particularly evident for the population receiving standard-dose chemotherapy (median OS not yet reached; P = .02). By multivariate Cox regression analysis, low serum b2M at diagnosis (P = .001), absence of a del(13q) (P = .004), high-dose therapy (P = .034), and presence of t(11;14)/no del(13q) (P = .069) emerged as independent favorable parameters for OS. Thus, according to the cytogenetic pattern, three prognostic groups of patients could be discriminated (P < .001): patients with good [t(11;14), no del(13q)], intermediate [no t(11;14), no del(13q)], and poor prognosis [no t(11;14), del(13q)]. We conclude that MM with t(11;14) represents a heterogenous entity, and only the cytogenetic pattern t(11;14)/no del(13q) characterizes the most favorable prognostic group of MM, with sensitive disease to multiple lines of anti-MM therapy.