RESUMEN
Since 2000, we have investigated 67 consecutive patients with stage I/II follicular lymphoma (FL) for the presence of BCL2/IGH rearrangements by polymerase chain reaction (PCR), real time quantitative PCR (RQ-PCR) and digital droplet PCR (ddPCR). All patients were treated with involved-field radiotherapy (IF-RT) (24-30 Gy). From 2005, patients with minimal residual disease (MRD) after IF-RT received rituximab (R) (375 mg/m2 , 4 weekly administrations). The median follow-up is 82 months (17-196). At diagnosis, 72% of patients were BCL2/IGH+. Progression-free survival (PFS) was significantly better in patients with undetectable/low levels (<10-5 ) of circulating BCL2/IGH+ cells at diagnosis and in those who were persistently MRD- during follow-up (P = 0·0038). IF-RT induced an MRD- status in 50% of cases; 16/19 (84%) MRD+ patients after IF-RT became MRD- after R treatment. A significantly longer PFS was observed in MRD+ patients treated with R compared to untreated MRD+ patients (P = 0·049). In early stage FL, both circulating levels of BCL2/IGH+ cells at diagnosis and MRD status during follow-up bear prognostic implications. Standard IF-RT fails to induce an MRD-negative status in half of patients. Most patients become MRD- following treatment with R and this is associated with a significantly better PFS.
Asunto(s)
Linfoma Folicular/complicaciones , Neoplasia Residual/etiología , Rituximab/uso terapéutico , Femenino , Humanos , Linfoma Folicular/radioterapia , Masculino , Estadificación de Neoplasias , Neoplasia Residual/patología , Rituximab/farmacologíaRESUMEN
In chronic lymphocytic leukaemia (CLL), caution is warranted regarding the clinical implications of immunoglobulin variable heavy chain region (IGHV) rearrangements with a 'borderline' (BL) percentage of mutations (i.e. 97-97·9% IGHV identity). We analysed the IGHV mutational status in 759 untreated CLL patients (cohort 1). BL-CLL (n = 36, 5%) showed a time to first treatment (TFT) similar to that of M-CLL (n = 338) and significantly longer than that of UM-CLL (n = 385), despite the enrichment in subset #2 cases. In fact, CLLs belonging to subset #2 (n = 15/759, 2%) were significantly more frequent among BL-CLLs (n = 5/36, 14%), with a brief TFT. TFT of BL-CLL remained comparable to that of M-CLL also considering the 327 CLL patients evaluated at diagnosis. These findings were then validated in an independent cohort 2 of 759 newly diagnosed CLL patients (BL-CLL: n = 11, 1·4%) and in all newly diagnosed patients from cohorts 1 and 2 (n = 1 086, 84% stage A; BL-CLL: n = 47, 4·3%). BL-CLL at diagnosis showed a biological profile comparable to that of M-CLL with a low frequency of unfavourable prognostic markers, except for a significant enrichment in subset #2. Our data suggest that the prognosis of BL-CLL is good and similar to that of M-CLL, with the exception of subset #2 cases.
Asunto(s)
Reordenamiento Génico de Cadena Pesada de Linfocito B , Genes de las Cadenas Pesadas de las Inmunoglobulinas , Cadenas Pesadas de Inmunoglobulina/genética , Región Variable de Inmunoglobulina , Leucemia Linfocítica Crónica de Células B/mortalidad , Hipermutación Somática de Inmunoglobulina , ADP-Ribosil Ciclasa 1/análisis , Adulto , Anciano , Anciano de 80 o más Años , Antígenos de Neoplasias/análisis , Femenino , Humanos , Región Variable de Inmunoglobulina/genética , Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/terapia , Masculino , Glicoproteínas de Membrana/análisis , Persona de Mediana Edad , Mutación , Pronóstico , Estudios Retrospectivos , Tiempo de TratamientoAsunto(s)
Proteína 3 que Contiene Repeticiones IAP de Baculovirus/genética , Cromosomas Humanos Par 11/ultraestructura , Leucemia Linfocítica Crónica de Células B/genética , Eliminación de Secuencia , Adulto , Anciano , Anciano de 80 o más Años , Alelos , Aberraciones Cromosómicas , Cromosomas Humanos Par 11/genética , Análisis Mutacional de ADN , Femenino , Estudios de Seguimiento , Humanos , Hibridación Fluorescente in Situ , Leucemia Linfocítica Crónica de Células B/mortalidad , Masculino , Persona de Mediana Edad , PronósticoRESUMEN
Digital droplet PCR (ddPCR) is an implementation of conventional PCR, with the potential of overcoming some limitations of real-time quantitative PCR (RQ-PCR). To evaluate if ddPCR may improve the quantification of disease levels and refine patients' risk stratification, 116 samples at four time points from 44 (35 B-lineage and 9 T-lineage) adult Philadelphia-negative acute lymphoblastic leukemia patients enrolled in the GIMEMA LAL1913 protocol were analyzed by RQ-PCR and ddPCR. A concordance rate between RQ-PCR and ddPCR of 79% (P < 0.0001) was observed; discordances were identified in 21% of samples, with the majority being RQ-PCR-negative (NEG) or positive not quantifiable (PNQ). ddPCR significantly reduced the proportion of PNQ samples-2.6% versus 14% (P = 0.003)-and allowed disease quantifiability in 6.6% of RQ-PCR-NEG, increasing minimal residual disease quantification in 14% of samples. Forty-seven samples were also investigated by next-generation sequencing, which confirmed the ddPCR results in samples classified as RQ-PCR-PNQ or NEG. By reclassifying samples on the basis of the ddPCR results, a better event-free survival stratification of patients was observed compared to RQ-PCR; indeed, ddPCR captured more true-quantifiable samples, with five relapses occurring in three patients who resulted RQ-PCR-PNQ/NEG but proved ddPCR positive quantifiable. At variance, no relapses were recorded in patients whose follow-up samples were RQ-PCR-PNQ but reclassified as ddPCR-NEG. A broader application of ddPCR in acute lymphoblastic leukemia clinical trials will help to improve patients' stratification.