RKRichard J. Klasa

Richard J. Klasa

*This is an algorithmically generated author record based on publicly available information.

Current Organizations / Institutes

The organizations/institutes from the scholar's latest article


Richard J. Klasa has a total of 36 co-authors. Here are the top co-authors by number of shared publications:

  • R D Gascoyne

    4 shared publications
  • J M Connors

    3 shared publications
  • W Y Au

    3 shared publications
  • D E Horsman

    2 shared publications
  • D S Viswanatha

    2 shared publications
  • Andrew Maksymiuk

    From the Division of Medical Oncology, British Columbia Cancer Agency, Vancouver, British Columbia; Hamilton Regional Cancer Center, Hamilton, London Regional Cancer Centre, London, and St Catherine’s Clinic, St Catherine’s, Ontario; McGill Oncology Group, Hopital Saint-Luc, and Berlex Canada, Montreal, Quebec; Toronto-Sunnybrook Regional Cancer Centre, Toronto; Saskatoon Cancer Centre, Saskatoon, Saskatchewan; and Cancercare Manitoba, Winnipeg, Manitoba, Canada

    1 shared publication

Latest Publications

  • The use of FDG-PET to guide consolidative radiotherapy in patients with advanced-stage Hodgkin lymphoma with residual abnormalities on CT scan following ABVD chemotherapy.

    by K. J. Savage, J. M. Connors, R. J. Klasa, P. Hoskins, T. N. Shenkier, R. D. Gascoyne, S. Bhimji, T. Pickles, F. Benard, D. Wilson, et al.

    8034 Background: Consolidative radiotherapy (RT) is frequently administered following chemotherapy (CHT) for advanced stage Hodgkin lymphoma (HL) patients who have bulky disease at diagnosis and/or residual abnormalities on post-CHT CT imaging. The GHSG HD15 trial has recently shown that RT can be omitted in cases that have residual disease on CT imaging following BEACOPP-based CHT but are FDG-PET-negative (PET-neg). However, it is unknown whether this also applies to patients treated with ABVD CHT and to those with initial bulky disease. Further, the effectiveness of RT for cases that are PET positive (PET-pos) following ABVD CHT remains unclear. Methods: Since July 2005, adult (> 16 y) patients in British Columbia (BC) with advanced stage HL (stage III /IV and/or the presence B symptoms and/or bulky disease [> 10cm]) have been recommended to undergo FDG-PET imaging if residual abnormalities > 2 cm are seen on the post CHT CT scan. If the PET scan was negative, patients were observed, regardless of initial disease bulk. If the PET scan was positive RT was administered, if feasible. Results: In total, 163 patients responding patients have had a PET scan following curative intent ABVD or equivalent CHT: PET-neg 80% (n=130); PET-pos 19% (n=31); PET-indeterminate 1% (n=2). Patient characteristics include: M:F 1:1.04; median age, 31 y (17-76 y); stage II, 52%; bulky disease, 50%; B symptoms, 68%; IPFP Prognostic score > 3, 15%. With a median follow-up of 34 months, patients with a PET-neg scan post CHT have a far superior 3-year TTP compared to those with a PET-pos scan (89% vs 55%, p= .00001). In the PET-neg patients, there was no difference in the 3-year TTP in those with bulky vs non-bulky disease at diagnosis (86% vs 91%, p=.71). In the PET-pos group, 25 (81%) received the planned RT and of these, 10 (40%) have relapsed. Conclusions: Advanced stage HL patients with a negative PET scan following ABVD CHT are at low risk of relapse and do not routinely require additional consolidative RT thus avoiding potential long-term side effects. Although some patients with a positive PET-scan remain disease free after consolidative RT, a high proportion ultimately relapse.


    • 1 November 2004
      • Vol. 18, 25-31

    Targeting the proapoptotic factor Bcl-2 in non-Hodgkin's lymphoma.

    by Richard J Klasa

    Bcl-2 functions as a key survival factor for lymphocytes and is highly expressed in a majority of non-Hodgkin's lymphomas. The ability of oblimersen sodium (Genasense, previously known as G3139) to target bcl-2 messenger RNA and decrease Bcl-2 protein levels has the potential to enhance the activity of cytotoxic chemotherapy. Pretreatment with oblimersen followed by cyclophosphamide (Cytoxan, Neosar) markedly improved survival relative to single-agent cyclophosphamide in a murine xenograft model. Oblimersen has also enhanced the cytotoxicity of a variety of other agents against non-Hodgkin's lymphoma, including etoposide, rituximab (Rituxan), and alemtuzumab (Campath). An initial phase I study of oblimersen in non-Hodgkin's lymphoma demonstrated modest single-agent activity. Recent reports suggest that oblimersen may add to the activity of R-CHOP (rituximab-cyclophosphamide/doxorubicin/vincristine/prednisone) in previously untreated mantle cell lymphoma and to rituximab alone in a variety of subtypes of relapsed non-Hodgkin's lymphoma. Additional studies in both treatment-naive and relapsed patients will define the role of oblimersen in the treatment of non-Hodgkin's lymphoma.


  • Randomized Phase III Study of Fludarabine Phosphate Versus Cyclophosphamide, Vincristine, and Prednisone in Patients With Recurrent Low-Grade Non-Hodgkin’s Lymphoma Previously Treated With an Alkylating Agent or Alkylator-Containing Regimen

    by Richard J. Klasa, Ralph M. Meyer, Chaim Shustik, Carol A. Sawka, Anne Smith, Raymond Guévin, Andrew Maksymiuk, Morel Rubinger, Martin Samosh, Suzanne Laplante, et al.

    PURPOSE: To compare in a phase III study the safety and efficacy of fludarabine to that of cyclophosphamide, vincristine, and prednisone (CVP) in recurrent, low-grade, non-Hodgkin’s lymphoma after previous response to systemic treatment. PATIENTS AND METHODS: Patients were randomized to fludarabine (25 mg/m2 intravenously on days 1 to 5, every 28 days) or CVP (cyclophosphamide 750 mg/m2 and vincristine 1.2 mg/m2 both intravenously on day 1 and prednisone 40 mg/m2 orally on days 1 to 5, every 21 days). The primary outcome assessed was progression-free survival (PFS); secondary outcomes included treatment-free survival (TFS), overall survival (OS), treatment-related toxicity, and quality of life (QoL) according to the European Organization for Research and Treatment of Cancer’s Quality of Life Questionnaire C-30 version 1.0 instrument. RESULTS: Ninety-one patients were randomized, 47 to fludarabine and 44 to CVP. There was no difference in response rates, with 64% (complete response [CR], 9%) for fludarabine versus 52% (CR, 7%) for CVP (P = .72). With a median follow-up of 42 months, median PFS (11 months v 9.1 months; P = .03) and TFS (15 months v 11 months; P = .02) were superior in patients receiving fludarabine. No difference in median overall survival was detected (57 months for fludarabine v 44 months for CVP; P = .95). Three patients receiving fludarabine died of treatment-related toxicity compared with none of the patients receiving CVP. Peripheral neuropathy and alopecia were more common with CVP. Patients receiving fludarabine had higher scores for social function (P = .008); no other differences in QoL were detected. CONCLUSION: In recurrent low-grade lymphoma, fludarabine improves PFS, TFS, and social function scores in comparison with CVP but does not improve OS.


  • Bcl-3/IgH translocation (14;19)(q32;q13) in Non-Hodgkin's Lymphomas

    by W.Y. Au, D.E. Horsman, H. Ohno, R.J. Klasa, R.D. Gascoyne

    The recurrent cytogenetic (CG) abnormality t(14;19)(q32;q13) involving the oncogene BCL3 is described in patients with atypical chronic lymphocytic leukemia (CLL). We report four patients with non-Hodgkin's lymphoma (NHL) bearing t(14;19). All cases were female and their age ranged from 62 to 91. Histologically, there were two cases of small lymphocytic lymphoma (SLL), both CD11c positive with atypical morphology, one case of Burkitt like lymphoma (BLL), and one case of diffuse large cell lymphoma (DLC-L). One SLL patient showed t(14;19) as the sole abnormality and experienced a benign course for 8 years. The other three cases showed secondary CG progression, including tetraploidy, del(6q), t(8;22) and del(13q). These cases were aggressive in clinical behavior, including an SLL case which transformed to DLC lymphoma in 4 months. Southern analysis and long distance PCR confirmed BCL3/IgH C α translocation in one case. We propose that NHLs with t(14;19) may have evolved from the same spectrum of disease as atypical CLL. The poor prognosis of t(14;19) disease is associated with the occurrence of recurrent secondary CG changes, commonly found in B cell lymphoproliferative diseases.


    • 1 November 2000
      • Vol. 85  (11) , 1225-7

    8q24 translocations in blastic transformation of mantle cell lymphoma.

    by W Y Au, D E Horsman, D S Viswanatha, J M Connors, R J Klasa, R D Gascoyne


    • 1 June 2000
      • Vol. 6  (6) , 2492-500

    Eradication of human non-Hodgkin's lymphoma in SCID mice by BCL-2 antisense oligonucleotides combined with low-dose cyclophosphamide.

    by R J Klasa, M B Bally, R Ng, J H Goldie, R D Gascoyne, F M Wong

    Cancers overexpressing Bcl-2 protein, which prevents programmed cell death (apoptosis), are less sensitive to stresses that produce cellular damage, including chemotherapy. If the level of Bcl-2 protein can be reduced sufficiently using antisense oligonucleotides (ASOs) targeting the gene message, then cytotoxic agents may be rendered more effective in eliminating disease and increasing cure rate. Preclinical studies in SCID mice bearing Bcl-2 overexpressing systemic human B-cell lymphoma (DoHH2) were undertaken to support development of a clinical trial. These data confirm that a combination of an ASO (5 mg/kg) targeting bcl-2 and a low dose of cyclophosphamide (35 mg/kg) was an effective strategy, leading to the eradication of the DoHH2 cells in vivo and cure of the animals. When mice deficient in natural killer cell activity were treated with an ASO, similar results were observed, suggesting that ASO stimulation of the host immune system was not a significant factor in elimination of lymphoma cells. These studies indicate that therapeutic strategies involving the use of an ASO targeting bcl-2 in combination with a cytotoxic agent may improve clinical outcomes.


    • 1 May 1999
      • Vol. 105  (2) , 437-40

    Concurrent chromosomal alterations at 3q27, 8q24 and 18q21 in B-cell lymphomas.

    by W Y Au, R D Gascoyne, D S Viswanatha, B F Skinnider, J M Connors, R J Klasa, D E Horsman

    Recurrent chromosomal translocations in malignant lymphomas most commonly involve 18q21(bcl-2), 8q24 (c-myc) and 3q27 (bcl-6), with an incidence of 27%, 11% and 6%, respectively. Individual cases concurrently harbouring two of these three rearrangements have been previously reported. This report describes four patients with cytogenetic alterations affecting all three loci, which was confirmed by molecular analysis in one case. Clinically, each patient had aggressive B-cell lymphoma with disseminated disease often involving the central nervous system, poor response to chemotherapy and short survival. Activation of c-myc in association with deregulation of bcl-2, bcl-6 or both confers high-grade disease with a poor prognosis.


    • 15 August 1998
      • Vol. 92  (4) , 1160-4

    Second malignancies in patients with hairy cell leukemia in british columbia: a 20-year experience.

    by W Y Au, R J Klasa, R Gallagher, N Le, R D Gascoyne, J M Connors

    The purpose of this study was to compare the relative risk of second malignancies in a cohort of patients with hairy cell leukemia (HCL) against the normal population. Potential effects of type of treatment and duration of follow-up and the site distribution of cancer were also examined. Between 1976 and 1996, 117 patients were diagnosed with HCL in British Columbia who were referred to the British Columbia Cancer Agency (BCCA) for treatment. All additional malignancies were traced using a provincial population-based cancer registry and follow-up records from the BCCA. There were 90 men and 27 women. Median age at diagnosis was 53 years. The median follow-up time was 68 months. Twenty-three patients underwent primary splenectomy, 65 received interferon alpha, 24 deoxycoformycin, and 67 cladribine (2-chlorodeoxyadenosine). Thirty-six patients had an additional malignancy (30.7%) with a total of 44 tumors. Six patients (5.1%) had two or more malignancies. Twenty-five patients had malignancies diagnosed after HCL (21.3%), three concurrent with HCL (2.6%), and 12 preceding HCL (10.2%). Second tumors (n = 28 tumors) occurred at a median of 40 months after HCL (range, 3 to 167). The relative rate (RR) of second malignancy among men and women was 2.91 (P < .001) and 1.65 (P = .23), respectively, compared with age and secular trend-matched controls. There were eight prostate cancers, nine nonmelanoma skin cancers, two lung cancers, and four gastrointestinal adenocarcinomas. The RR (90% confidence interval [CI]) in the various treatment groups were: splenectomy (RR = 0.21 to 3.81), purine analogues (RR = 0.60 to 5.69), interferon then purine analogues (RR = 1.60 to 4.31), interferon alone (RR = 1. 57 to 8.40). Cancer risk peaked at 2 years after HCL (RR = 4.13) and fell steadily afterwards, reaching a RR of 1.82 at 6 years. Twenty patients died, six due to HCL, 10 due to second malignancies, and four of unrelated causes. HCL patients appear to be inherently prone to malignancies. This appears to be more related to HCL tumor burden than to genetic predisposition or treatment effect. RR tends to fall with time after effective treatment. However, close monitoring for and vigorous prevention of cancer in HCL patients is advisable.