L R Prosnitz

Koo Foundation Sun Yat-Sen Cancer Center, T’ai-pei, Taipei, Taiwan

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Publications (192)935.67 Total impact

  • Lawrence B Marks, Leonard R Prosnitz
    Journal of Clinical Oncology 12/2013; · 18.04 Impact Factor
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    ABSTRACT: Multiple randomized studies have demonstrated that chemotherapy, most commonly ABVD (doxorubicin [Adriamycin], bleomycin, vinblastine, dacarbazine), followed by consolidation radiation therapy is the most effective treatment program for early-stage Hodgkin lymphoma. With a combined-modality approach, the great majority of patients are cured of their disease. It is also apparent that both chemotherapy and radiation therapy can increase the risk of complications in the decades following treatment, with second cancers and cardiac disease being the most common. Most studies,evaluating such risks primarily include patients treated in decades past with what are now considered outdated approaches, including high-dose, wide-field radiation therapy. The treatment of Hodgkin lymphoma has evolved significantly, particularly in regard to radiation therapy. In combination with chemotherapy, much lower doses and smaller fields are employed, with success equivalent to that achieved using older methods. Many studies have shown a significant decline in both the rates of second cancers and the risk of cardiac disease with low-dose radiation confined to the original extent of disease. In favorable patients, as few as 2 cycles of ABVD have been shown to be effective. The current combined-modality approach seeks to maintain high cure rates but minimize risks by optimizing both chemotherapy and radiation therapy
    Oncology (Williston Park, N.Y.) 12/2012; 26(12):1182-9, 1193. · 3.19 Impact Factor
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    ABSTRACT: PURPOSE: This study is designed to validate a previously developed locoregional recurrence risk (LRR) scoring system and further define which groups of patients with breast cancer would benefit from postmastectomy radiation therapy (PMRT). METHODS AND MATERIALS: An LRR risk scoring system was developed previously at our institution using breast cancer patients initially treated with modified radical mastectomy between 1990 and 2001. The LRR score comprised 4 factors: patient age, lymphovascular invasion, estrogen receptor negativity, and number of involved lymph nodes. We sought to validate the original study by examining a new dataset of 1545 patients treated between 2002 and 2007. RESULTS: The 1545 patients were scored according to the previously developed criteria: 920 (59.6%) were low risk (score 0-1), 493 (31.9%) intermediate risk (score 2-3), and 132 (8.5%) were high risk (score ≥4). The 5-year locoregional control rates with and without PMRT in low-risk, intermediate-risk, and high-risk groups were 98% versus 97% (P=.41), 97% versus 91% (P=.0005), and 89% versus 50% (P=.0002) respectively. CONCLUSIONS: This analysis of an additional 1545 patients treated between 2002 and 2007 validates our previously reported LRR scoring system and suggests appropriate patients for whom PMRT will be beneficial. Independent validation of this scoring system by other institutions is recommended.
    International journal of radiation oncology, biology, physics 11/2012; · 4.59 Impact Factor
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    ABSTRACT: Advanced cervical cancer is routinely treated with radiotherapy and cisplatin-containing chemotherapy. Hyperthermia has been shown to improve the results of both radiotherapy and cisplatin. The feasibility of the combination of all three modalities was demonstrated and reported in a study of 68 previously untreated cervical cancer patients in 2005. Long-term follow-up is presented here. Sixty-eight patients with advanced cervical cancer were prospectively registered in the USA, Norway and the Netherlands, and treated with a combination of radiotherapy (external beam radiotherapy and brachytherapy for a biologically effective dose of at least 86.7 Gy), chemotherapy (at least four courses of weekly cisplatin (40 mg/m(2))) and locoregional hyperthermia (four weekly sessions). Long-term follow-up was gathered and recurrence-free survival (RFS) and overall survival (OS) curves and survival estimates were obtained. Median follow-up was 81 months. Tumours in 28 patients have recurred, 21 of whom have died. Five-year RFS from the day of registration in the study is 57.5% (95%CI: 46.6-71.0) and five-year OS is 66.1% (95%CI: 55.1-79.3). Differences between countries can be explained by patient characteristics. The long-term survival results of the combination of full-dose radiotherapy, chemotherapy and hyperthermia fall well within previous reports for this patient group in randomised trials. The small trial size and lack of randomisation do not permit further interpretation.
    International Journal of Hyperthermia 07/2012; 28(6):549-53. · 2.59 Impact Factor
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    ABSTRACT: To examine the efficacy of different radiation doses after achievement of a complete response to chemotherapy in diffuse large B-cell lymphoma (DLBCL). Patients with stage I-IV DLBCL treated from 1995-2009 at Duke Cancer Institute who achieved a complete response to chemotherapy were reviewed. In-field control, event-free survival, and overall survival were calculated using the Kaplan-Meier method. Dose response was evaluated by grouping treated sites by delivered radiation dose. 105 patients were treated with RT to 214 disease sites. Chemotherapy (median 6 cycles) was R-CHOP (65%), CHOP (26%), R-CNOP (2%), or other (7%). Post-chemotherapy imaging was PET/CT (88%), gallium with CT (1%), or CT only (11%). The median RT dose was 30 Gy (range, 12-40 Gy). The median radiation dose was higher for patients with stage I-II disease compared with patients with stage III-IV disease (30 versus 24.5 Gy, p < 0.001). Five-year in-field control, event-free survival, and overall survival for all patients was 94% (95% CI: 89-99%), 84% (95% CI: 77-92%), and 91% (95% CI: 85-97%), respectively. Six patients developed an in-field recurrence at 10 sites, without a clear dose response. In-field failure was higher at sites ≥ 10 cm (14% versus 4%, p = 0.06). In-field control was excellent with a combined modality approach when a complete response was achieved after chemotherapy without a clear radiation dose response.
    Radiation Oncology 06/2012; 7:100. · 2.11 Impact Factor
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    ABSTRACT: While consolidation radiation therapy (i.e., RT administered after chemotherapy) is routine treatment for patients with early-stage diffuse large B-cell lymphoma (DLBCL), the role of consolidation RT in stage III-IV DLBCL is controversial. Cases of patients with stage III-IV DLBCL treated from 1991 to 2009 at Duke University, who achieved a complete response to chemotherapy were reviewed. Clinical outcomes were calculated using the Kaplan-Meier method and were compared between patients who did and did not receive RT, using the log-rank test. A multivariate analysis was performed using Cox proportional hazards model. Seventy-nine patients were identified. Chemotherapy (median, 6 cycles) consisted of anti-CD20 antibody rituximab combined with cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP; 65%); cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP; 22%); or other (13%). Post-chemotherapy imaging consisted of positron emission tomography (PET)/computed tomography (CT) (73%); gallium with CT (14%); or CT only (13%). Consolidation RT (median, 25 Gy) was given to involved sites of disease in 38 (48%) patients. Receipt of consolidation RT was associated with improved in-field control (92% vs. 69%, respectively, p = 0.028) and event-free survival (85% vs. 65%, respectively, p = 0.014) but no difference in overall survival (85% vs. 78%, respectively, p = 0.15) when compared to patients who did not receive consolidation RT. On multivariate analysis, no RT was predictive of increased risk of in-field failure (hazard ratio [HR], 8.01, p = 0.014) and worse event-free survival (HR, 4.3, p = 0.014). Patients with stage III-IV DLBCL who achieve negative post-chemotherapy imaging have improved in-field control and event-free survival with low-dose consolidation RT.
    International journal of radiation oncology, biology, physics 03/2012; 84(3):762-7. · 4.59 Impact Factor
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    ABSTRACT: To evaluate treatment results and prognostic factors, especially margin status and molecular subtype, in early-stage breast cancer patients treated with breast conservation therapy (BCT). The records of 1,058 Stage I or II breast cancer patients treated with BCT (surgical excision plus radiotherapy) at Duke University Medical Center, Durham, North Carolina, from 1985-2005 were retrospectively reviewed. Conventional receptor analyses were used as surrogate markers for molecular subtype classification (luminal A, luminal B, Her2 positive, and basal like). Actuarial estimates of overall survival (OS), cause-specific survival (CSS), failure-free survival, and locoregional control (LRC) were computed by use of Kaplan-Meier plots. We analyzed prognostic variables for significance using Cox proportional hazards univariate and multivariate analysis. The study was approved by the Duke University Medical Center Institutional Review Board. The median age of the patients was 56 years (range, 18-89 years). Of the patients, 80% had T1 disease and 66% N0 disease pathologically. With a median follow-up of 9.8 years, an in-breast recurrence developed in 53 patients and 10 patients had nodal failure. For all patients, the 10-year CSS rate was 94%; LRC rate, 94%; and failure-free survival rate, 88%. Luminal A patients had a CSS rate of 95% and LRC rate of 99%. Basal-type patients appeared to do worse, with regard to both CSS rate (74%) and LRC rate (76%), but the numbers were small and the difference was not statistically significant. LRC rates of patients with negative margins (widely negative, close, and extent of margin not known) were virtually identical (93%, 96%, and 94%, respectively). Those with positive margins appeared to fare slightly worse based on LRC rate (88%), but again, the numbers were small and the difference was not statistically significant. BCT remains the treatment of choice for early-stage breast cancer patients irrespective of molecular subtype. Negative margins of excision are desirable, but the width of the negative margin does not influence outcome.
    International journal of radiation oncology, biology, physics 12/2011; 83(3):814-20. · 4.59 Impact Factor
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    ABSTRACT: 2-[fluorine-18]fluoro-2-deoxy-D-glucose-positron emission tomography (PET) and gallium-67 citrate (gallium) response after chemotherapy are powerful prognostic factors in diffuse large B-cell lymphoma (DLBCL). However, clinical outcomes when consolidation radiation therapy (RT) is administered are less defined. We reviewed 99 patients diagnosed with DLBCL from 1996 to 2007 at Duke University who had a post-chemotherapy response assessment with either PET or gallium and who subsequently received consolidation RT. Clinical outcomes were estimated using the Kaplan-Meier method and compared using the log-rank test. Median follow-up was 4.4 years. Stage distribution was I-II in 70% and III-IV in 30%. Chemotherapy was R-CHOP or CHOP in 88%. Median RT dose was 30 Gy. Post-chemotherapy PET (n = 79) or gallium (n = 20) was positive in 21 of 99 patients and negative in 78 of 99 patients. Five-year in-field control was 95% with a negative PET/gallium scan versus 71% with a positive scan (P < 0.01). Five-year event-free survival (EFS; 83% versus 65%, P = 0.04) and overall survival (89% versus 73%, P = 0.04) were also significantly better when the post-chemotherapy PET/gallium was negative. A positive PET/gallium scan after chemotherapy is associated with an increased risk of local failure and death. Consolidation RT, however, still results in long-term EFS in 65% of patients.
    Annals of Oncology 02/2011; 22(2):405-10. · 7.38 Impact Factor
  • Fuel and Energy Abstracts 01/2011; 81(2).
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    ABSTRACT: Several recent series evaluating external beam accelerated partial breast irradiation (PBI) have reported adverse cosmetic outcomes, possibly related to large volumes of normal tissue receiving near-prescription doses. We hypothesized that delivery of external beam PBI in a single fraction to the preoperative tumor volume would be feasible and result in a decreased dose to the uninvolved breast compared with institutional postoperative PBI historical controls. A total of 17 patients with unifocal Stage T1 breast cancer were identified. Contrast-enhanced subtraction magnetic resonance images were loaded into an Eclipse treatment planning system and used to define the target volumes. A "virtual plan" was created using four photon beams in a noncoplanar beam arrangement and optimized to deliver 15 Gy to the planning target volume. The median breast volume was 1,713 cm(3) (range: 1,014-2,140), and the median clinical target volume was 44 cm(3) (range: 26-73). In all cases, 100% of the prescription dose covered 95% of the clinical target volume. The median conformity index was 0.86 (range: 0.70-1.12). The median percentage of the ipsilateral breast volume receiving 100% and 50% of the prescribed dose was 3.8% (range: 2.2-6.9) and 13.3% (range: 7.5-20.8) compared with 18% (range: 3-42) and 53% (range: 24-65) in the institutional historical controls treated with postoperative external beam PBI (p = .002). The median maximum skin dose was 9 Gy. The median dose to 1 and 10 cm(3) of skin was 6.7 and 4.9 Gy. The doses to the heart and ipsilateral lung were negligible. Preoperative PBI resulted in a substantial reduction in ipsilateral breast tissue dose compared with postoperative PBI. The skin dose appeared reasonable, given the small volumes. A prospective Phase I trial evaluating this technique is ongoing.
    International journal of radiation oncology, biology, physics 11/2010; 82(1):37-42. · 4.59 Impact Factor
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    ABSTRACT: Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin lymphoma in the United States. Historically, radiation therapy (RT) was the primary treatment for patients with localized disease. Several randomized trials have demonstrated that the addition of systemic therapy improves outcomes. Additional randomized trials have shown that the combination of RT and systemic therapy is superior to systemic therapy alone. The role of RT in advanced-stage DLBCL has not been firmly established, but some prospective phase III trials, as well as retrospective studies, suggest a benefit for advanced disease also. For patients with relapsed or primary refractory disease, autologous stem cell transplantation is the treatment of choice. Here too, consolidation RT appears to improve outcomes compared with autologous stem cell transplant alone. Finally, for patients with advanced DLBCL who are no longer responsive to systemic therapy, RT may provide rapid and durable palliation of local lymphoma-related symptoms.
    Oncology (Williston Park, N.Y.) 11/2010; 24(13):1204-12. · 3.19 Impact Factor
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    ABSTRACT: Chest wall recurrences of breast cancer are a therapeutic challenge and durable local control is difficult to achieve. Our objective was to determine the local progression free survival (LPFS) and toxicity of thermochemoradiotherapy (ThChRT) for chest wall recurrence. Twenty-seven patients received ThChRT for chest wall failure from 2/1995 to 6/2007 and make up this retrospective series. All received concurrent superficial hyperthermia twice weekly (median 8 sessions), chemotherapy (capecitabine in 21, vinorelbine in 2, and paclitaxel in 4), and radiation (median 45 Gy). Patients were followed up every 1.5-3 months and responses were graded with RECIST criteria and toxicities with the NCI CTC v4.0. Twenty-three (85%) patients were previously irradiated (median 60.4 Gy) and 22 (81%) patients received prior chemotherapy. Median follow-up was 11 months. Complete response (CR) was achieved in 16/20 (80%) of patients with follow-up data, and 1 year LPFS was 76%. Overall survival was 23 months for patients with CR, and 5.4 months in patients achieving a partial response (PR) (p=0.01). Twenty-two patients experienced acute grade 1/2 treatment related toxicities, primarily moist desquamation. Two patients experienced 3rd degree burns; all resolved with conservative measures. ThChRT offers durable palliation and prolonged LPFS with tolerable acute toxicity, especially if CR is achieved.
    Radiotherapy and Oncology 11/2010; 97(3):535-40. · 4.52 Impact Factor
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    ABSTRACT: We present a study of the prevalence of genetic polymorphisms and expression of genes encoding the drug-resistance proteins glutathione S-transferases (GSTs) in order to gain insights into the pattern of failure evident in mantle cell lymphoma. We note a high preponderance of genetic alterations conferring resistance to standard chemotherapy in this illness. Concurrent with this investigation, we present a series of patients who were provided dose-dense and intense chemotherapy to circumvent these drug-resistance mechanisms. High responses were noted, though durable remissions were few, indicating non-traditional chemotherapy options are important to investigate in this illness.
    Cancer Investigation 07/2010; 28(6):654-60. · 2.24 Impact Factor
  • Journal of the National Comprehensive Cancer Network: JNCCN 03/2010; 8(3):288-334. · 5.11 Impact Factor
  • Leonard R Prosnitz
    International journal of radiation oncology, biology, physics 02/2010; · 4.59 Impact Factor
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    ABSTRACT: Hyperthermia has long been used in combination with radiation for the treatment of superficial malignancies, in part due to its radiosensitising capabilities. Patients who suffer superficial recurrences of breast cancer, be it in their chest wall following mastectomy, or in their breast after breast conservation, typically have poor clinical outcomes. They often develop distant metastatic disease, but one must not overlook the problems associated with an uncontrolled local failure. Morbidity is enormous, and can significantly impair quality of life. There is no accepted standard of care in treating superficial recurrences of breast cancer, particularly in patients that have previously been irradiated. There is a substantial literature regarding the combined use of hyperthermia and radiotherapy for these superficial recurrences. Most of it is retrospective in nature, but there are several larger phase III randomised trials that show an improved rate of clinical complete response in patients treated with both modalities. In this review article, we will highlight the important prospective data that has been published regarding the combined use of hyperthermia and radiation.
    International Journal of Hyperthermia 01/2010; 26(7):612-7. · 2.59 Impact Factor
  • Fuel and Energy Abstracts 01/2010; 78(3).
  • L.B. Marks, L.R. Prosnitz
    Breast Diseases A Year Book Quarterly 01/2010; 21(2):173–175.
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    ABSTRACT: Hyperthermia (HT) has a proven benefit for treating superficial malignancies, particularly chest wall recurrences of breast cancer. There has been less research utilising HT in patients with locally advanced breast cancer (LABC), but available data are promising. HT has been combined with chemotherapy and/or radiotherapy in the neoadjuvant, definitive and adjuvant setting, albeit in series with small numbers of patients. There is only one phase III trial that examines hyperthermia in LABC, also with relatively small numbers of patients. The goal of this review is to highlight important research utilising HT in patients with LABC as well as to suggest future directions for its use.
    International Journal of Hyperthermia 01/2010; 26(7):618-24. · 2.59 Impact Factor
  • Fuel and Energy Abstracts 01/2010; 78(3).

Publication Stats

5k Citations
935.67 Total Impact Points

Institutions

  • 2006–2012
    • Koo Foundation Sun Yat-Sen Cancer Center
      T’ai-pei, Taipei, Taiwan
  • 1985–2011
    • Duke University Medical Center
      • • Division of Medical Oncology
      • • Department of Radiation Oncology
      Durham, NC, United States
  • 1999–2009
    • Duke University
      Durham, North Carolina, United States
  • 2005
    • West Virginia University
      • Department of Obstetrics and Gynecology
      Morgantown, WV, United States
  • 1993
    • Pinehurst Radiology
      North Carolina, United States
  • 1990
    • University of California, Los Angeles
      • Department of Radiation Oncology
      Los Angeles, CA, United States
  • 1975–1982
    • Yale-New Haven Hospital
      • Department of Pathology
      New Haven, Connecticut, United States
  • 1978
    • Danbury Hospital
      Danbury, Connecticut, United States