Response and survival in African American (AA) patients (pts) with non-small cell lung cancer (NSCLC) treated with erlotinib (E)

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Background: Pts who respond to the EGFR- tyrosine kinase inhibitors (TKI's) frequently have activating mutations in the kinase domain of EGFR or EGFR overexpression. EGFR activating mutations correlate with adenocarcinoma histology, non-smoking history, female gender, and Asian ethnicity. The presence of EGFR kinase domain mutations is predictive of response but, the relationship is not always concordant. Furthermore, mutations may not predict survival benefit with TKI therapy and other factors are likely involved. It has also been determined that EGFR and met can crosstalk, and serve as potential mechanism of resistance in NSCLC. Most data collected to date on response and overall survival with EGFR-TKI's have been in the Caucasian or Asian community. Hence we collected data specific to the AA pt as they tend to have worse outcomes stage for stage. The purpose of this study is to report the response rate, overall survival, progression free survival (PFS) and clinical characteristics of AA pts with NSCLC treated with an EGFR-TKI. We will correlate these data with EGFR mutation and c-Met expression/mutations/amplifications for markers of NSCLC. Methods: We have listed patients with NSCLC receiving E therapy over the past 5 years. We then retrospectively collected demographic data (age, race, sex, and tobacco history), tumor histology, response rates, survival data and duration of response from AA pts treated with E as single agent. The response to E was correlated with outcome. Results: Data from 44 AA pts (27 women, 17 men) on erlotinib were reviewed. Mean age was 67.1 years (range 48–89 yrs), tobacco use (37 positive, 3 negative, and 4 not recorded). Histology included NSCLC not specified-14, squamous cell- 16, adenocarcinoma-11, large cell-1 and 2 not available. Overall response rate of 13.6% (6-PR, 16-SD, 18-progessive disease, and 4 patients lost to follow up). The PFS was 4.0 months; 95% CI: (2.5–6.6 mos) and overall survival 8.6 mos; 95% CI: (7.2–30.9 mos). EGFR mutations and c-Met analysis will be provided by ASCO meeting in May 2009. Conclusions: AA survival and response rates appear similar to previous data seen with all NSCLC patients receiving treatment with EGFR-TKI's. More data and relationship to biomarkers is needed in this population.

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Randomized trial of filgrastim versus chemotherapy and filgrastim mobilization of hematopoietic progenitor cells for rescue in autologous transplantation

Peripheral blood cell (PBC) rescue has become the mainstay for autologous transplantation in patients with lymphoma, multiple myeloma, and solid tumors. Different methods of hematopoietic progenitor cell (HPC) mobilization are in use without an established standard. Forty-seven patients with relapsed or refractory lymphoma received salvage chemotherapy and were randomized to have HPC mobilization using filgrastim [granulocyte-colony-stimulating factor (G-CSF)] alone for 4 days at 10 microg/kg per day (arm A) or cyclophosphamide (5 g/m(2)) and G-CSF at 10 microg/kg per day until hematologic recovery (arm B). Engraftment and ease of PBC collection were primary outcomes. All patients underwent the same high-dose chemotherapy followed by reinfusion of PBCs. There were no differences in median time to neutrophil engraftment (11 days in both arms; P =.5) or platelet engraftment (14 days in arm A, 13 days in arm B; P =.35). Combined chemotherapy and G-CSF resulted in higher CD34(+) cell collection than G-CSF alone (median, 7.2 vs 2.5 x 10(6) cells/kg; P =.004), but this did not impact engraftment. No differences were found in other PBC harvest outcomes or resource utilization measures. A high degree of tumor contamination, as studied by consensus CDR3 polymerase chain reaction of the mobilized PBCs, was present in both arms (92% in arm A vs 90% in arm B; P = 1). No differences were found in overall survival or progression-free survival at a median follow-up of 21 months. This randomized trial provides clinical evidence that the use of G-CSF alone is adequate for HPC mobilization, even in heavily pretreated patients with relapsed lymphoma.

Randomized trial of peripheral blood progenitor cell vs bone marrow as hematopoietic support for high-dose chemotherapy in patients with non-Hodgkin's lymphoma and Hodgkin's disease: a clinical and molecular analysis

Filgrastim (r-metHuG-CSF)-mobilized peripheral blood progenitor cells (PBPC) and unstimulated bone marrow (BM) were evaluated and compared for reconstitution after high-dose chemotherapy in patients with relapsed Hodgkin's disease (HD) or non-Hodgkin's lymphoma (NHL) with respect to engraftment, overall and relapse-free survival, and contamination by lymphoma cells using molecular analysis of immunoglobulin gene rearrangements. Forty-four patients with either NHL or HD underwent autologous transplantation after high-dose chemotherapy. Patients were randomized to receive either Filgrastim-mobilized PBPC (n = 15) or unstimulated BM (n = 14). An additional 15 patients received PBPC without randomization because of a recent history of marrow involvement by lymphoma. Use of PBPC was associated with faster neutrophil engraftment than BM (11 vs 14 days to an absolute neutrophil count >0.5 x 10(9)/l, P = 0.04), but without any difference in platelet engraftment, infectious complications, or overall or event-free survival. Both BM (65%) and PBPC (73%) were frequently contaminated by tumor cells as assessed by CDR3 analysis. Patients with negative polymerase chain reaction analysis of a BM sample during the study had a trend towards an improved survival; however, BM involvement by disease had no impact on the ability to mobilize or collect PBPC. We conclude that PBPC are as effective as BM in reconstituting hematopoiesis after high-dose chemotherapy and that both products are frequently contaminated by sequences marking the malignant clone.

High degree of occult tumor contamination in bone marrow and peripheral blood stem cells of patients undergoing autologous transplantation for non-Hodgkin's lymphoma

Twenty patients with non-Hodgkin's lymphoma (NHL), primarily intermediate-and high-grade, were evaluated for evidence of bone marrow (BM) or peripheral blood stem cell (PBSC) lymphoma contamination using tumor-specific oligonucleotide-polymerase chain reaction (TSO-PCR). Patients were enrolled in a single-institution study comparing PBSC and bone marrow transplantation (BMT) for relapsed NHL. A molecular marker (CDR3 rearrangement, T cell beta receptor [TC beta R] rearrangement, or BCL-2/IgH rearrangement) was identified from analysis of the diagnostic tissue in 17 of 20 patients. Prior to undergoing BMT, 14 of 17 patients had PCR evidence of lymphoma involvement of either BM (11/17) or PBSCs (9/11). No decrease was found in the frequency of contamination of PBSCs compared with BM. In one patient, quantitative competitive PCR (C-PCR) identified a three- to tenfold greater quantity of contamination in the BM compared with PBSC. All evaluated patients (6/6) with contamination prior to BMT had persistence of marrow contamination following BMT. Our data demonstrate that TSO-PCR can generate a molecular marker for the majority of patients with intermediate- and high-grade NHL. In addition, we identified a high rate of occult lymphoma involvement in both BM and PBSC. As demonstrated by C-PCR, however, quantitative differences may exist in contamination of BM and PBSCs.