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Dive into the research topics where Cynthia G. Leichman is active.

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Featured researches published by Cynthia G. Leichman.


Journal of Clinical Oncology | 1997

Quantitation of intratumoral thymidylate synthase expression predicts for disseminated colorectal cancer response and resistance to protracted-infusion fluorouracil and weekly leucovorin.

Cynthia G. Leichman; Heinz-Josef Lenz; Lawrence Leichman; Kathleen D. Danenberg; Joaquina Baranda; Susan Groshen; William D. Boswell; Ralf Metzger; Matthew Tan; Peter V. Danenberg

PURPOSE Response rates to fluorouracil (5-FU)-based therapy remain low. As new, active agents are being tested, information regarding specific intratumoral genetic determinants of chemotherapy sensitivity or resistance can be used to plan therapy rationally. Intratumoral thymidylate synthase (TS) quantitation may be among the most important determinants of sensitivity or resistance to 5-FU. MATERIALS AND METHODS Forty-six disseminated colorectal cancer patients had measurable tumor biopsies for polymerase chain reaction (PCR)-based determination of TS mRNA pretreatment. Protracted infusion of 5-FU 200 mg/m2/d for 21 days with weekly intravenous leucovorin 20 mg/m2 each cycle was given. After two cycles, responses were evaluated. Response data were correlated with independently determined intratumoral ratios of TS/beta-actin mRNA for each patient. RESULTS TS/beta-actin ratios were successfully obtained for 42 patients (91%). TS/beta-actin ratios ranged from 0.3 x 10(-3) to 18.2 x 10(-3) (median, 3.5 x 10[-3]). Twelve patients (26%) responded to treatment (median TS/beta-actin ratio, 1.7 x 10[+3]). Thirty-four patients did not respond (median TS/beta-actin ratio, 5.6 x 10[-3]). No patient with a TS mRNA level greater than 4.1 x 10(-3) responded. The median TS/beta-actin ratio (3.5 x 10[-3]) significantly segregated responders from nonresponders (P = .001). Median survival for patients with TS/beta-actin ratios < or = 3.5 x 10(-3) was 13.6 months; for patients with TS/beta-actin ratios greater than 3.5 x 10(-3), it was 8.2 months (P = .02). CONCLUSION For this cohort, the intratumoral TS/beta-actin ratio had a statistically significant association with response and survival. This relationship for other 5-FU schedules remains unknown. Confirmation of these data in a larger patient population could lead to determination of therapy for disseminated colorectal cancer based on a specific intratumoral molecular parameter.


Journal of Clinical Oncology | 1998

ERCC1 mRNA levels complement thymidylate synthase mRNA levels in predicting response and survival for gastric cancer patients receiving combination cisplatin and fluorouracil chemotherapy.

Ralf Metzger; Cynthia G. Leichman; Kathleen D. Danenberg; Peter V. Danenberg; Heinz-Josef Lenz; Kazuhiko Hayashi; Susan Groshen; Dennis Salonga; Hartley Cohen; Loren Laine; Peter F. Crookes; Howard Silberman; Joaquina Baranda; Brahma Konda; Lawrence Leichman

PURPOSE We have previously shown that relative thymidylate synthase (TS) mRNA levels in primary gastric adenocarcinomas treated with fluorouracil (5-FU) and cisplatin are inversely associated with response and survival. This is a presumed function of TS as a target for 5-FU activity. We now test the hypotheses that the relative mRNA level of the excision repair cross-complementing (ERCC1) gene is inversely associated with response and survival as an independent function of cisplatin efficacy. PATIENTS AND METHODS Patients had intact, untreated, primary gastric adenocarcinoma cancer and were evaluated for eligibility on a preoperative cisplatin infusion-5-FU protocol. cDNA, derived from primary gastric tumors before chemotherapy, was used to determine ERCC1 mRNA levels, expressed as the ratio of polymerase chain reaction (PCR) product of the ERCC1 gene and the beta-actin gene. RESULTS The median ERCC1 mRNA level from 38 primary gastric cancers (33 assessable for response) was 5.8 x 10(-3) (range, 1.8 x 10(-3) to 19.5 x 10(-3)). Of 17 responding patients, 13 (76%) were less than or equal to 5.8 x 10(-3) and four were greater than 5.8 x 10(-3) (P = .003). The median survival for patients with ERCC1 mRNA levels less than or equal to 5.8 x 10(-3) has not been reached, whereas for those greater than 5.8 x 10(-3) it was 5.4 months (P = .034). The median TS mRNA level, 3.7 x 10(-3) (range, 0.9 to 18.9) also segregated responsive versus resistant tumors (P = .024). With both ERCC1 and TS mRNA levels below their medians, 11 of 13 patients (85%) responded; with both ERCC1 and TS mRNA levels above their medians, two of 10 patients (20%) responded (P = .003). CONCLUSION Considered separately, either ERCC1 or TS mRNA levels in a primary gastric adenocarcinoma has a statistically significant relationship to response. ERCC1 mRNA levels have a statistically significant association with survival; in this cohort TS mRNA levels did not reach statistically significant association with survival as in our previous publication. Whether these molecular parameters are independent of each other as predictors of outcome remains to be determined.


Journal of Clinical Oncology | 1996

Thymidylate synthase mRNA level in adenocarcinoma of the stomach: a predictor for primary tumor response and overall survival.

Heinz-Josef Lenz; Cynthia G. Leichman; Kathleen D. Danenberg; Peter V. Danenberg; Susan Groshen; Hartley Cohen; Loren Laine; Peter F. Crookes; Howard Silberman; Joaquina Baranda; Yolee Garcia; James Li; Lawrence Leichman

PURPOSE We tested the hypothesis that polymerase chain reaction (PCR) quantitation of the enzyme thymidylate synthase (TS) within a primary adenocarcinoma of the stomach, has an inverse relationship to response and survival for patients who receive fluorouracil (5FU)-based chemotherapy. PATIENTS AND METHODS Before systemic chemotherapy, the genetic expression of TS (TSmRNA level) was determined using a PCR method. Gene expression was calculated by determining the ratio between the amount of radiolabeled PCR product with the linear amplification range of the TS gene and the beta-actin gene. Chemotherapy consisted of two cycles of protracted infusion (PI) 5FU 200 mg/m2/d administered for 3 weeks with leucovorin 20 mg/m2/w. Cisplatin 100 mg/m2 was administered on day 1. RESULTS Sixty-five patients with primary gastric cancer had a median TS mRNA level of 4.6 x 10(-3) (range, 0.9 to 20.1 x 10(-3)). Thirty-five percent of patients had measurable responses in their primary tumors. The mean gastric cancer TSmRNA level in responding and resistant patients is statistically significant (P < .001). The median survival time was 43+ months for treated patients with TSmRNA levels less than the median and 6 months for those with TS m-RNA levels greater than the median (P = .003). CONCLUSION The genetic expression of TS (TSmRNA level) influences response to 5FU-based chemotherapy and survival for a cohort of patients with primary gastric cancer. Confirmation of these data could lead to therapeutic decisions based on specific molecular properties within a tumor.


Journal of Clinical Oncology | 2008

Randomized Phase II Trial of a Toll-Like Receptor 9 Agonist Oligodeoxynucleotide, PF-3512676, in Combination With First-Line Taxane Plus Platinum Chemotherapy for Advanced-Stage Non–Small-Cell Lung Cancer

Christian Manegold; Donald Gravenor; Donald Woytowitz; J. Mezger; Vera Hirsh; Gary Albert; Mohammed Al-Adhami; David Robert John Readett; Arthur M. Krieg; Cynthia G. Leichman

PURPOSE This study assessed the efficacy of the combination of standard taxane plus platinum chemotherapy with the synthetic Toll-like receptor 9-activating oligodeoxynucleotide PF-3512676 in patients with non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS Chemotherapy-naive patients with stage IIIB to IV NSCLC were randomly assigned (one to two ratio) to receive four to six cycles of taxane/platinum chemotherapy alone or with 0.2 mg/kg of subcutaneous PF-3512676 on days 8 and 15 of each 3-week cycle. The primary end point was objective response rate (ORR). RESULTS Baseline demographics were similar between treatment arms, although significantly more patients in the PF-3512676 arm had stage IV disease (85% compared with 62% in the chemotherapy-alone arm). The modified intent-to-treat analysis (n = 111) demonstrated a 38% ORR (confirmed and unconfirmed) in the PF-3512676 arm (n = 74) and 19% in the chemotherapy-alone arm (n = 37) by investigator evaluation. Blinded, independent radiologic review for 90 patients showed a similar trend in confirmed response rate (19% and 11%, respectively). Median survival was 12.3 months in the PF-3512676 arm and 6.8 months in the chemotherapy-alone arm, and 1-year survival was 50% and 33%, respectively. Mild to moderate local injection site reactions and flu-like symptoms were the most common PF-3512676-related adverse events, but grade 3/4 neutropenia, thrombocytopenia, and anemia were all reported more commonly for patients in the PF-3512676 arm. CONCLUSION The addition of PF-3512676 to taxane plus platinum chemotherapy for first-line treatment of NSCLC improves objective response and may improve survival. Confirmatory phase III trials are ongoing.


Journal of Clinical Oncology | 2006

Phase III Trial of Fluorouracil-Based Chemotherapy Regimens Plus Radiotherapy in Postoperative Adjuvant Rectal Cancer: GI INT 0144

Stephen R. Smalley; Jacqueline Benedetti; Stephen K. Williamson; John M. Robertson; Norman C. Estes; Tracy Maher; Barbara Fisher; Tyvin A. Rich; James A. Martenson; John W. Kugler; Al B. Benson; Daniel G. Haller; Robert J. Mayer; James N. Atkins; Christine Cripps; J. Pedersen; Phillip O. Periman; Michael Tanaka; Cynthia G. Leichman; John S. Macdonald

PURPOSE Adjuvant chemoradiotherapy after or before resection of high-risk rectal cancer improves overall survival (OS) and pelvic control. We studied three postoperative fluorouracil (FU) radiochemotherapy regimens. PATIENTS AND METHODS After resection of T3-4, N0, M0 or T1-4, N1, 2M0 rectal adenocarcinoma, 1,917 patients were randomly assigned to arm 1, with bolus FU in two 5-day cycles every 28 days before and after radiotherapy (XRT) plus FU via protracted venous infusion (PVI) 225 mg/m2/d during XRT; arm 2 (PVI-only arm), with PVI 42 days before and 56 days after XRT + PVI; or arm 3 (bolus-only arm), with bolus FU + leucovorin (LV) in two 5-day cycles before and after XRT, plus bolus FU + LV (levamisole was administered each cycle before and after XRT). Patients were stratified by operation type, T and N stage, and time from surgery. RESULTS Median follow-up was 5.7 years. Lethal toxicity was less than 1%, with grade 3 to 4 hematologic toxicity in 49% to 55% of the bolus arms versus 4% in the PVI arm. No disease-free survival (DFS) or OS difference was detected (3-year DFS, 67% to 69% and 3-year OS, 81% to 83% in all arms). Locoregional failure (LRF) at first relapse was 8% in arm 1, 4.6% in arm 2, and 7% in arm 3. LRF in T1-2, N1-2, and T3, N0-2 primaries who received low anterior resection (those most suitable for primary resection) was 5% in arm 1, 3% in arm 2, and 5% in arm 3. CONCLUSION All arms provide similar relapse-free survival and OS, with different toxicity profiles and central catheter requirements. LRF with postoperative therapy is low, justifying initial resection for T1-2, N0-2 and T3, and N0-2 anterior resection candidates.


Journal of Clinical Oncology | 2002

Oxaliplatin in Combination With Protracted-Infusion Fluorouracil and Radiation: Report of a Clinical Trial for Patients With Esophageal Cancer

Nikhil I. Khushalani; Cynthia G. Leichman; Gary M. Proulx; Hector R. Nava; Lisa M. Bodnar; Donald L. Klippenstein; Alan Litwin; Judy L. Smith; Enriqueta Nava; Lakshmi Pendyala; Patrick F. Smith; William R. Greco; Joanne Berdzik; Harold O. Douglass; Lawrence Leichman

PURPOSE To identify a dose and schedule of oxaliplatin (OXP) to be safely administered in combination with protracted-infusion (PI) fluorouracil (5-FU) and external-beam radiation therapy (XRT) for patients with primary esophageal carcinoma (EC). PATIENTS AND METHODS Eligibility included therapeutically naïve EC patients with clinical disease stages II, III, or IV. Initial doses and schedules for cycle 1 consisted of OXP 85 mg/m(2) on days 1, 15, and 29; PI 5-FU 180 mg/m(2) for 24 hours for 35 days; and XRT 1.8 Gy in 28 fractions starting on day 8. At completion of cycle 1, eligible patients could undergo an operation or begin cycle 2 without XRT. Postoperative patients were eligible for cycle 2. Stage IV patients were allowed three cycles in the absence of disease progression. OXP and 5-FU increases were based on dose-limiting toxicity (DLT) encountered in cohorts of three consecutive patients. RESULTS Thirty-eight eligible patients received therapy: 22 noninvasively staged as IV and 16 noninvasively staged as II and III. Thirty-six patients completed cycle 1, 29 patients started cycle 2, and 24 patients completed cycle 2. The combined-modality therapy was well tolerated, but DLT prevented OXP and 5-FU escalation. No grade 4 hematologic toxicity was noted. Eleven grade 3 and two grade 4 clinical toxicities were noted in eight patients. After cycle 1, 29 patients (81%) had no cancer in the esophageal mucosa. Thirteen patients underwent an operation with intent to resect the esophagus; five patients (38%) exhibited pathologic complete responses. CONCLUSION OXP 85 mg/m(2) on days 1, 15, and 29 administered with PI 5-FU and XRT is safe, tolerable, and seems effective against primary EC. The role of OXP in multimodality regimens against EC deserves further evaluation.


Oncologist | 2013

Neoadjuvant Doxorubicin/Cyclophosphamide Followed by Ixabepilone or Paclitaxel in Early Stage Breast Cancer and Evaluation of βIII-Tubulin Expression as a Predictive Marker

Cristina Saura; Ling Ming Tseng; Stephen Chan; Raju Titus Chacko; Mario Campone; Alexy Manikhas; Shona Nag; Cynthia G. Leichman; Lokanatha Dasappa; Peter A. Fasching; Fernando Hurtado de Mendoza; W. Fraser Symmans; David Liu; Pralay Mukhopadhyay; Christine Horak; Guan Xing; Lajos Pusztai

BACKGROUND This randomized phase II trial was designed to compare the rate of pathologic complete response (pCR) induced by neoadjuvant cyclophosphamide plus doxorubicin (AC) followed by ixabepilone or paclitaxel in women with early stage breast cancer (BC). Expression of βIII-tubulin as a predictive marker was also evaluated. PATIENTS AND METHODS Women with untreated, histologically confirmed primary invasive breast adenocarcinoma received four cycles of AC followed by 1:1 randomization to either ixabepilone 40 mg/m2 (3-hour infusion) every 3 weeks for four cycles (n = 148) or weekly paclitaxel 80 mg/m2 (1-hour infusion) for 12 weeks (n = 147). All patients underwent a core needle biopsy of the primary cancer for molecular marker analysis prior to chemotherapy. βIII-Tubulin expression was assessed using immunohistochemistry. RESULTS There was no significant difference in the rate of pCR in the ixabepilone treatment arm (24.3%; 90% confidence interval [CI], 18.6-30.8) and the paclitaxel treatment arm (25.2%; 90% CI, 19.4-31.7). βIII-Tubulin-positive patients obtained higher pCR rates compared with βIII-tubulin-negative patients in both treatment arms; however, βIII-tubulin expression was not significantly associated with a differential response to ixabepilone or paclitaxel. The safety profiles of both regimens were generally similar, although neutropenia occurred more frequently in the ixabepilone arm (grade 3/4: 41.3% vs. 8.4%). The most common nonhematologic toxicity was peripheral neuropathy. CONCLUSIONS Neoadjuvant treatment of early stage BC with AC followed by ixabepilone every 3 weeks or weekly paclitaxel was well tolerated with no significant difference in efficacy. Higher response rates were observed among βIII-tubulin-positive patients.


Cancer Journal | 2002

Effect of concurrent radiation therapy and chemotherapy on pulmonary function in patients with esophageal cancer: dose-volume histogram analysis.

Thomas Gergel; Lawrence Leichman; Hector R. Nava; Leslie E. Blumenson; Gregory M. Loewen; John F. Gibbs; Nikhil I. Khushalani; Cynthia G. Leichman; Lisa M. Bodnar; Harold O. Douglass; Judy L. Smith; Michael Kuettel; Gary M. Proulx

PURPOSEThe pulmonary effects of concurrent radiation therapy and chemotherapy were studied in patients enrolled in a phase I trial for esophageal cancer. MATERIALS AND METHODSPulmonary function tests were performed prospectively before and after combined-modality therapy (oxaliplatin, 5-fluorouracil, and radiation therapy) in 20 patients with esophageal cancer. Cumulative and differential lung DVH analysis from 0 to 5400 cGy in 25-cGy intervals was performed for the last 15 patients. Correlation between radiation exposure in various dose ranges and percent reduction in pulmonary function tests was calculated as an exploratory analysis. RESULTSSignificant reductions in carbon monoxide diffusion capacity corrected for hemoglobin (12. 3%) and total lung capacity (2. 5%) were evident at a median of 15. 5 days after radiation therapy. DVH analysis revealed that the single dose of maximum correlation between lung volume radiation exposure and lung function reduction was less than 1000 cGy for all pulmonary functions. The percent lung volume that received a total dose between 700 and 1000 cGy maximally correlated with the percent reductions in total lung capacity and vital capacity, and the absolute lung volume that received a total dose between 700 and 1000 cGy maximally correlated with the percent reductions in total lung capacity, vital capacity, and carbon monoxide diffusion capacity. DISCUSSIONSignificant declines in carbon monoxide diffusion capacity and total lung capacity are evident immediately after the administration of conformal radiation therapy, oxaliplatin, and 5-fluorouracil for esophageal cancer. Other lung functions remain statistically unchanged. The percent or absolute lung volume that received a total dose between 700 and 1000 cGy may be significantly correlated with the percent decline of carbon monoxide diffusion capacity, total lung capacity, and vital capacity. These associations will be evaluated further in a follow-up study


Journal of Chemotherapy | 2006

Expression of Genes Related to Activity of Oxaliplatin and 5-Fluorouracil in Endoscopic Biopsies of Primary Esophageal Cancer in Patients Receiving Oxaliplatin, 5-Flourouracil and Radiation: Characterization and Exploratory Analysis with Survival

Lawrence Leichman; D. Lawrence; Cynthia G. Leichman; Hector R. Nava; Enriqueta Nava; Gary M. Proulx; K. Clark; Nikhil I. Khushalani; Joanne Berdzik; William R. Greco; P. Smith; P.J. Creaven; J.L. Kepner; M.M. Javle; Lakshmi Pendyala

Abstract With a goal of identifying relations between gene expression and response (mucosal or pathological) or survival in esophageal cancer patients (stages II to IV) receiving oxaliplatin, 5-fluorouracil (5FU) and radiation, we measured in endoscopic primary tumor biopsies from 38 patients, the expression of seven genes (γGCS, γGT, MRP-2, ERCC-1, XPA, TS and DPD) prior to treatment, 1 week following oxaliplatin alone and at the end of the combined radio-chemotherapy cycle using real time QRT-PCR. A higher pretreatment level of XPA was related to shorter survival with a hazard ratio of 2.43 (90% confidence interval 1.09 to 5.43) using Cox regression modeling. However, multivariate analysis with a Cox model indicated low expression of XPA or TS and combined stages II and III had a higher probability of survival (for XPA: hazard ratio 3.0 and 90% C.I. of 1.3 to 6.9, with adjustment for stage included; for TS: hazard ratio is 1.98 with 90% C.I. of 0.94 to 4.20. The expression of TS, γGCS, ERCC-1 and MRP-2 declined from D 1 to the end of the cycle (p<0.05, sign test). A validation and further understanding of the findings need to be carried out in a larger study with a more homogeneous population of patients. Abbreviations used: 5FU, 5-fluorouracil; γGCS, γglutamylcysteine synthetase; γGT, gglutamyltranspeptidase; MRP-2, multidrug resistance protein 2; ERCC-1, excision- repair cross-complementing gene1; XPA, xeroderma pigmentosum A; TS, thymidylate synthase; DPD, dihydropyrimidine dehydrogenase; GST-π, glutathione S-transferase π; P-gp, P-glycoprotein; GSH, glutathione; 5FU, 5-fluorouracil; D, day; QC, quality control; CV, coefficient of variation; XRT, radiation therapy; PFS, Progression-free Survival; HR, Hazard Ratio; QRT-PCR, quantitative reverse transcriptase polymerase chain reaction; C.I. Confidence interval.


Diseases of The Colon & Rectum | 2015

HIV Infection Is Associated With Poor Outcomes for Patients With Anal Cancer in the Highly Active Antiretroviral Therapy Era.

David Grew; Danielle S. Bitterman; Cynthia G. Leichman; Lawrence Leichman; Nicholas Sanfilippo; Harvey G. Moore; K.L. Du

BACKGROUND: HIV status may affect outcomes after definitive chemoradiotherapy for anal cancer. OBJECTIVE: Here, we report a large series in the highly active antiretroviral therapy era comparing outcomes between HIV-positive and HIV-negative patients with anal cancer. DESIGN: This was a retrospective chart review. SETTINGS: The study was conducted at an outpatient oncology clinic at large academic center. PATIENTS: A total of 107 patients were reviewed, 39 HIV positive and 68 HIV negative. All of the patients underwent definitive chemoradiation for anal cancer. MAIN OUTCOME MEASURES: Data on patient characteristics, treatment, toxicity, and outcomes were collected. Overall survival, colostomy-free survival, local recurrence-free survival, and distant metastasis-free survival were analyzed. RESULTS: Median follow-up was 15 months. HIV-positive patients were younger (median, 52 vs 64 years; p < 0.001) and predominantly men (82% men vs 49% men; p = 0.001). There were no significant differences in T, N, or stage groups. HIV-positive patients had a significantly longer duration from biopsy to start of chemoradiation (mean number of days, 82 vs 54; p = 0.042). There were no differences in rates of acute toxicities including diarrhea, fatigue, or dermatitis. HIV-positive patients had significantly higher rates of hospitalization (33% vs 15%; p = 0.024). The 3-year overall survival rate was 42% in HIV-positive and 76% in HIV-negative patients (p = 0.037; HR, 2.335 (95% CI, 1.032–5.283)). Three-year colostomy-free survival was 67% in HIV-positive and 88% in HIV-negative patients (p = 0.036; HR, 3.231 (95% CI, 1.014–10.299)). Differences in overall survival rates were not significant on multivariate analysis. LIMITATIONS: This study was limited by its retrospective design and small patient numbers. CONCLUSIONS: In this cohort, HIV-positive patients had significantly worse overall and colostomy-free survival rates than HIV-negative patients. However, differences in survival were not significant on multivariate analysis. Additional studies are necessary to establish the etiology of this difference.

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Lawrence Leichman

University of Southern California

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Heinz-Josef Lenz

University of Southern California

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Susan Groshen

University of Southern California

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Kathleen D. Danenberg

University of Southern California

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Peter V. Danenberg

University of Southern California

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