Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where L. Portelance is active.

Publication


Featured researches published by L. Portelance.


Cancer | 1999

The importance of hemoglobin levels during radiotherapy for carcinoma of the cervix

Michelle Grogan; Gillian Thomas; Iris Melamed; Frances Wong; R. Pearcey; Paul K. Joseph; L. Portelance; Juanita Crook; Keith D. Jones

It is unclear whether blood transfusion can overcome the negative impact of anemia before or during radiotherapy (RT) in patients with carcinoma of the cervix. The objective of this retrospective study was to examine the impact of anemia and blood transfusion on 605 patients with carcinoma of the cervix treated with radical RT at 7 centers across Canada in 1989, 1990, and 1992.


International Journal of Radiation Oncology Biology Physics | 2011

Consensus Guidelines for Delineation of Clinical Target Volume for Intensity-Modulated Pelvic Radiotherapy for the Definitive Treatment of Cervix Cancer

Karen Lim; William Small; L. Portelance; Carien L. Creutzberg; Ina M. Jürgenliemk-Schulz; Arno J. Mundt; Loren K. Mell; Nina A. Mayr; Akila N. Viswanathan; Anuja Jhingran; Beth Erickson; Jennifer F. De Los Santos; David K. Gaffney; Catheryn M. Yashar; Sushil Beriwal; Aaron H. Wolfson; Alexandra Taylor; Walter R. Bosch; Issam El Naqa; Anthony Fyles

PURPOSE Accurate target definition is vitally important for definitive treatment of cervix cancer with intensity-modulated radiotherapy (IMRT), yet a definition of clinical target volume (CTV) remains variable within the literature. The aim of this study was to develop a consensus CTV definition in preparation for a Phase 2 clinical trial being planned by the Radiation Therapy Oncology Group. METHODS AND MATERIALS A guidelines consensus working group meeting was convened in June 2008 for the purposes of developing target definition guidelines for IMRT for the intact cervix. A draft document of recommendations for CTV definition was created and used to aid in contouring a clinical case. The clinical case was then analyzed for consistency and clarity of target delineation using an expectation maximization algorithm for simultaneous truth and performance level estimation (STAPLE), with kappa statistics as a measure of agreement between participants. RESULTS Nineteen experts in gynecological radiation oncology generated contours on axial magnetic resonance images of the pelvis. Substantial STAPLE agreement sensitivity and specificity values were seen for gross tumor volume (GTV) delineation (0.84 and 0.96, respectively) with a kappa statistic of 0.68 (p < 0.0001). Agreement for delineation of cervix, uterus, vagina, and parametria was moderate. CONCLUSIONS This report provides guidelines for CTV definition in the definitive cervix cancer setting for the purposes of IMRT, building on previously published guidelines for IMRT in the postoperative setting.


International Journal of Radiation Oncology Biology Physics | 2012

Pelvic Normal Tissue Contouring Guidelines for Radiation Therapy: A Radiation Therapy Oncology Group Consensus Panel Atlas

H. Joseph Barthold; Elizabeth O'Meara; Walter R. Bosch; Issam El Naqa; Rawan Al-Lozi; Seth A. Rosenthal; Colleen A. Lawton; W. Robert Lee; Howard M. Sandler; Anthony L. Zietman; Robert J. Myerson; Laura A. Dawson; Christopher G. Willett; Lisa A. Kachnic; Anuja Jhingran; L. Portelance; Janice Ryu; William Small; David K. Gaffney; Akila N. Viswanathan; Jeff M. Michalski

PURPOSE To define a male and female pelvic normal tissue contouring atlas for Radiation Therapy Oncology Group (RTOG) trials. METHODS AND MATERIALS One male pelvis computed tomography (CT) data set and one female pelvis CT data set were shared via the Image-Guided Therapy QA Center. A total of 16 radiation oncologists participated. The following organs at risk were contoured in both CT sets: anus, anorectum, rectum (gastrointestinal and genitourinary definitions), bowel NOS (not otherwise specified), small bowel, large bowel, and proximal femurs. The following were contoured in the male set only: bladder, prostate, seminal vesicles, and penile bulb. The following were contoured in the female set only: uterus, cervix, and ovaries. A computer program used the binomial distribution to generate 95% group consensus contours. These contours and definitions were then reviewed by the group and modified. RESULTS The panel achieved consensus definitions for pelvic normal tissue contouring in RTOG trials with these standardized names: Rectum, AnoRectum, SmallBowel, Colon, BowelBag, Bladder, UteroCervix, Adnexa_R, Adnexa_L, Prostate, SeminalVesc, PenileBulb, Femur_R, and Femur_L. Two additional normal structures whose purpose is to serve as targets in anal and rectal cancer were defined: AnoRectumSig and Mesorectum. Detailed target volume contouring guidelines and images are discussed. CONCLUSIONS Consensus guidelines for pelvic normal tissue contouring were reached and are available as a CT image atlas on the RTOG Web site. This will allow uniformity in defining normal tissues for clinical trials delivering pelvic radiation and will facilitate future normal tissue complication research.


BMC Cancer | 2012

A retrospective study of neoadjuvant FOLFIRINOX in unresectable or borderline-resectable locally advanced pancreatic adenocarcinoma

Peter J. Hosein; J. Macintyre; Carolina Kawamura; Jennifer Cudris Maldonado; Vinicius Ernani; Arturo Loaiza-Bonilla; Govindarajan Narayanan; Afonso Ribeiro; L. Portelance; Jaime R. Merchan; Joe U. Levi; Caio Rocha-Lima

Background5-fluorouracil, leucovorin, irinotecan and oxaliplatin (FOLFIRINOX) is superior to gemcitabine in patients with metastatic pancreatic cancer who have a good performance status. We investigated this combination as neoadjuvant therapy for locally advanced pancreatic cancer (LAPC).MethodsIn this retrospective series, we included patients with unresectable LAPC who received neoadjuvant FOLFIRINOX with growth factor support. The primary analysis endpoint was R0 resection rate.ResultsEighteen treatment-naïve patients with unresectable or borderline resectable LAPC were treated with neoadjuvant FOLFIRINOX. The median age was 57.5 years and all had ECOG PS of 0 or 1. Eleven (61 %) had tumors in the head of the pancreas and 9 (50 %) had biliary stents placed prior to chemotherapy. A total of 146 cycles were administered with a median of 8 cycles (range 3-17) per patient. At maximum response or tolerability, 7 (39 %) were converted to resectability by radiological criteria; 5 had R0 resections, 1 had an R1 resection, and 1 had unresectable disease. Among the 11 patients who remained unresectable after FOLFIRINOX, 3 went on to have R0 resections after combined chemoradiotherapy, giving an overall R0 resection rate of 44 % (95 % CI 22–69 %). After a median follow-up of 13.4 months, the 1-year progression-free survival was 83 % (95 % CI 59-96 %) and the 1-year overall survival was 100 % (95 % CI 85-100 %). Grade 3/4 chemotherapy-related toxicities were neutropenia (22 %), neutropenic fever (17 %), thrombocytopenia (11 %), fatigue (11 %), and diarrhea (11 %). Common grade 1/2 toxicities were neutropenia (33 %), anemia (72 %), thrombocytopenia (44 %), fatigue (78 %), nausea (50 %), diarrhea (33 %) and neuropathy (33 %).ConclusionsFOLFIRINOX followed by chemoradiotherapy is feasible as neoadjuvant therapy in patients with unresectable LAPC. The R0 resection rate of 44 % in this population is promising. Further studies are warranted.


International Journal of Radiation Oncology Biology Physics | 2013

Hematologic Toxicity in RTOG 0418: A Phase 2 Study of Postoperative IMRT for Gynecologic Cancer

Ann H. Klopp; Jennifer Moughan; L. Portelance; Brigitte Miller; Mohammad Salehpour; Evangeline Hildebrandt; Jenny Nuanjing; David D'Souza; Luis Souhami; William Small; Rakesh Gaur; Anuja Jhingran

PURPOSE Intensity modulated radiation therapy (IMRT), compared with conventional 4-field treatment, can reduce the volume of bone marrow irradiated. Pelvic bone marrow sparing has produced a clinically significant reduction in hematologic toxicity (HT). This analysis investigated HT in Radiation Therapy Oncology Group (RTOG) 0418, a prospective study to test the feasibility of delivering postoperative IMRT for cervical and endometrial cancer in a multiinstitutional setting. METHODS AND MATERIALS Patients in the RTOG 0418 study were treated with postoperative IMRT to 50.4 Gy to the pelvic lymphatics and vagina. Endometrial cancer patients received IMRT alone, whereas patients with cervical cancer received IMRT and weekly cisplatin (40 mg/m(2)). Pelvic bone marrow was defined within the treatment field by using a computed tomography density-based autocontouring algorithm. The volume of bone marrow receiving 10, 20, 30, and 40 Gy and the median dose to bone marrow were correlated with HT, graded by Common Terminology Criteria for Adverse Events, version 3.0, criteria. RESULTS Eighty-three patients were eligible for analysis (43 with endometrial cancer and 40 with cervical cancer). Patients with cervical cancer treated with weekly cisplatin and pelvic IMRT had grades 1-5 HT (23%, 33%, 25%, 0%, and 0% of patients, respectively). Among patients with cervical cancer, 83% received 5 or more cycles of cisplatin, and 90% received at least 4 cycles of cisplatin. The median percentage volume of bone marrow receiving 10, 20, 30, and 40 Gy in all 83 patients, respectively, was 96%, 84%, 61%, and 37%. Among cervical cancer patients with a V40 >37%, 75% had grade 2 or higher HT compared with 40% of patients with a V40 less than or equal to 37% (P =.025). Cervical cancer patients with a median bone marrow dose of >34.2 Gy also had higher rates of grade ≥ 2 HT than did those with a dose of ≤ 34.2 Gy (74% vs 43%, P=.049). CONCLUSIONS Pelvic IMRT with weekly cisplatin is associated with low rates of HT and high rates of weekly cisplatin use. The volume of bone marrow receiving 40 Gy and the median dose to bone marrow correlated with higher rates of grade ≥ 2 toxicity among patients receiving weekly cisplatin (cervical cancer patients). Evaluation and limitation of the volume of bone marrow treated with pelvic IMRT is warranted in patients receiving concurrent chemotherapy.


International Journal of Radiation Oncology Biology Physics | 2014

Comparison and consensus guidelines for delineation of clinical target volume for CT- and MR-based brachytherapy in locally advanced cervical cancer

Akila N. Viswanathan; Beth Erickson; David K. Gaffney; Sushil Beriwal; Sudershan K. Bhatia; O. Burnett; David D'Souza; Nikhilesh Patil; Michael G. Haddock; Anuja Jhingran; Ellen L. Jones; Charles A. Kunos; Larissa J. Lee; Lilie L. Lin; Nina A. Mayr; Ivy A. Petersen; Primoz Petric; L. Portelance; William Small; Jonathan B. Strauss; Kanokpis Townamchai; Aaron H. Wolfson; Catheryn M. Yashar; Walter R. Bosch

OBJECTIVE To create and compare consensus clinical target volume (CTV) contours for computed tomography (CT) and 3-Tesla (3-T) magnetic resonance (MR) image-based cervical-cancer brachytherapy. METHODS AND MATERIALS Twenty-three experts in gynecologic radiation oncology contoured the same 3 cervical cancer brachytherapy cases: 1 stage IIB near-complete response (CR) case with a tandem and ovoid, 1 stage IIB partial response (PR) case with tandem and ovoid with needles, and 1 stage IB2 CR case with a tandem and ring applicator. The CT contours were completed before the MRI contours. These were analyzed for consistency and clarity of target delineation using an expectation maximization algorithm for simultaneous truth and performance level estimation (STAPLE), with κ statistics as a measure of agreement between participants. The conformity index was calculated for each of the 6 data sets. Dice coefficients were generated to compare the CT and MR contours of the same case. RESULTS For all 3 cases, the mean tumor volume was smaller on MR than on CT (P<.001). The κ and conformity index estimates were slightly higher for CT, indicating a higher level of agreement on CT. The Dice coefficients were 89% for the stage IB2 case with a CR, 74% for the stage IIB case with a PR, and 57% for the stage IIB case with a CR. CONCLUSION In a comparison of MR-contoured with CT-contoured CTV volumes, the higher level of agreement on CT may be due to the more distinct contrast medium visible on the images at the time of brachytherapy. MR at the time of brachytherapy may be of greatest benefit in patients with large tumors with parametrial extension that have a partial or complete response to external beam. On the basis of these results, a 95% consensus volume was generated for CT and for MR. Online contouring atlases are available for instruction at http://www.nrgoncology.org/Resources/ContouringAtlases/GYNCervicalBrachytherapy.aspx.


International Journal of Radiation Oncology Biology Physics | 2012

A Phase II Study of Intensity Modulated Radiation Therapy to the Pelvis for Postoperative Patients With Endometrial Carcinoma: Radiation Therapy Oncology Group Trial 0418

Anuja Jhingran; Kathryn Winter; L. Portelance; Brigitte Miller; Mohammad Salehpour; Rakesh Gaur; Luis Souhami; William Small; Lawrence Berk; David K. Gaffney

PURPOSE To determine the feasibility of pelvic intensity modulated radiation therapy (IMRT) for patients with endometrial cancer in a multi-institutional setting and to determine whether this treatment is associated with fewer short-term bowel adverse events than standard radiation therapy. METHODS Patients with adenocarcinoma of the endometrium treated with pelvic radiation therapy alone were eligible. Guidelines for target definition and delineation, dose prescription, and dose-volume constraints for the targets and critical normal structures were detailed in the study protocol and a web-based atlas. RESULTS Fifty-eight patients were accrued by 25 institutions; 43 were eligible for analysis. Forty-two patients (98%) had an acceptable IMRT plan; 1 had an unacceptable variation from the prescribed dose to the nodal planning target volume. The proportions of cases in which doses to critical normal structures exceeded protocol criteria were as follows: bladder, 67%; rectum, 76%; bowel, 17%; and femoral heads, 33%. Twelve patients (28%) developed grade ≥2 short-term bowel adverse events. CONCLUSIONS Pelvic IMRT for endometrial cancer is feasible across multiple institutions with use of a detailed protocol and centralized quality assurance (QA). For future trials, contouring of vaginal and nodal tissue will need continued monitoring with good QA and better definitions will be needed for organs at risk.


Brachytherapy | 2011

Image-guided brachytherapy for cervical cancer: a Canadian Brachytherapy Group survey.

Simon Pavamani; David D’Souza; L. Portelance; Peter S. Craighead; Andrew Pearce; Laurel Traptow; Corinne M. Doll

PURPOSE To survey the current use and future plans for image-guided brachytherapy (BT) for cervical cancer by radiation oncologists in Canada. METHODS AND MATERIALS Canadian radiation oncologists treating gynecologic malignancies were identified in January 2009. A 29-item questionnaire (English and French) querying the current practice in the use of imaging in BT planning, and plans for transition to three-dimensional (3D) image guidance for BT for cervical cancer (curative intent, intact cervix), was electronically circulated. Questionnaire responses were tabulated and analyzed by respondent and by center. RESULTS Response rate was 62% (36 of 58 radiation oncologists), representing 71% (22 of 31) of Canadian radiation oncology centers with a gynecologic BT facility. Most of the centers were using high-dose-rate BT (68%), followed by low-dose-rate BT (23%) and pulsed dose-rate BT (10%). Main imaging used for treatment planning by center was plain X-ray (50%), computerized tomography (CT) (45%), and magnetic resonance imaging (MRI) (5%). For respondents using CT or MRI for planning, point A was the most common dose prescription point (50%), followed by gross tumor volume/clinical target volume as per Groupe Européen de Curiethérapie and the European Society for Therapeutic Radiology and Oncology guidelines (44%). For centers using plain X-rays for planning, 73% planned to transition to a 3D image-based approach, with the majority to adopt CT imaging. Eighty percent of respondents agreed that 3D image-guided BT should become standard of care for treatment of cervical cancer in Canada, and additionally support the development of national guidelines. CONCLUSIONS Most of the Canadian radiation oncologists surveyed and Canadian cancer centers are either using 3D imaging and planning or transitioning to a 3D image-based approach within the next year. Point A remained a commonly documented prescription point. Access to MRI was very low. These results may lead to national treatment guidelines.


Pancreatology | 2015

Full dose neoadjuvant FOLFIRINOX is associated with prolonged survival in patients with locally advanced pancreatic adenocarcinoma

Moh'd M. Khushman; Naomi Dempsey; Jennifer Cudris Maldonado; Arturo Loaiza-Bonilla; Michel Velez; Lauren Carcas; Daniel Dammrich; Jorge Hurtado-Cordovi; Ritesh Parajuli; Terri Pollack; Ana Paula P. Harwood; J. Macintyre; Ching Wei D. Tzeng; Jaime R. Merchan; Maria H. Restrepo; Ikechukwu Immanuel Akunyili; Afonso Ribeiro; Govindarajan Narayanan; L. Portelance; Danny Sleeman; Joe U. Levi; Caio Max S. Rocha Lima; Peter J. Hosein

BACKGROUND The efficacy of FOLFIRINOX for metastatic pancreatic cancer has led to its use in patients with earlier stages of disease. This study retrospectively analyzed a cohort of patients with locally-advanced pancreatic cancer (LAPC) treated with FOLFIRINOX. METHODS Between 2008 and 2013, 51 treatment-naïve patients with LAPC at a single institution received first-line FOLFIRINOX with neoadjuvant intent, at the full dose as described in the PRODIGE 4/ACCORD 11 study. Combined chemoradiation was administered for those who remained unresectable after maximum response to chemotherapy. The primary outcome measure was overall survival (OS), and secondary outcomes were progression-free survival (PFS) and margin-negative (R0) resection rate, and toxicity profile. RESULTS A total of 429 cycles of FOLFIRINOX were given with a median of 8 cycles (range 2-29) per patient; 66% of cycles were full dose. After chemotherapy, 27 (53%) received chemoradiation. The median OS was 35.4 months (95% CI 25.8-45). Ten (4 borderline resectable and 6 unresectable) patients had successful R0 resections; those who had R0 resections had a significantly longer survival than those who did not (3-year OS rate 67% versus 21%, log rank p = 0.042). Increasing number of full-dose cycles was significantly associated with increased survival. The toxicity profile was similar to previous reports of this regimen. CONCLUSIONS FOLFIRINOX is feasible as neoadjuvant therapy for LAPC. Although the R0 resection rate was only 20%, the median OS of almost 3 years appears promising. Dose intensity and duration were associated with increased survival in this study, arguing against dose attenuated versions of this regimen.


Radiation Oncology | 2006

Absence of toxicity with hypofractionated 3-dimensional radiation therapy for inoperable, early stage non-small cell lung cancer.

S. Faria; Luis Souhami; L. Portelance; Marie Duclos; Té Vuong; David Small; Carolyn R. Freeman

PurposeHypofractionated radiotherapy may overcome repopulation in rapidly proliferating tumors such as lung cancer. It is more convenient for the patients and reduces health care costs. This study reports our results on patients with medically inoperable, early stage, non-small cell lung cancer (NSCLC) treated with hypofractionation.Materials and methodsStage T1-2N0 NSCLC patients were treated with hypofractionation alone, 52.5 Gy/15 fractions, in 3 weeks, with 3-dimensional conformal planning. T1-2N1 patients with the hilar lymphnode close to the primary tumor were also eligible for this treatment. We did not use any approach to reduce respiratory motion, but it was monitored in all patients. Elective nodal radiotherapy was not performed. Routine follow up included assessment for acute and late toxicity and radiological tumor response. Median follow up time was 29 months for the surviving patients.ResultsThirty-two patients with a median age of 76 years, T1 = 15 and T2 = 17, were treated. Median planning target volume (PTV) volume was 150cc and median V16 of both lungs was 13%. The most important finding of this study is that toxicity was minimal. Two patients had grade ≤ 2 acute pneumonitis and 3 had mild (grade 1) acute esophagitis. There was no late toxicity. Actuarial 1 and 2-year overall survival rates are 78% and 56%, cancer specific survival rates (CSS) are 90% and 74%, and local relapse free survival rates are 93% and 76% respectively.Conclusion3-D planning, involved field hypofractionation at a dose of 52.5 Gy in 15 daily fractions is safe, well tolerated and easy radiation treatment for medically inoperable lung cancer patients. It shortens by half the traditional treatment. Results compare favorably with previously published studies. Further studies are needed to compare similar technique with other treatments such as surgery and stereotactic radiotherapy.

Collaboration


Dive into the L. Portelance's collaboration.

Top Co-Authors

Avatar

Luis Souhami

McGill University Health Centre

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Anuja Jhingran

University of Texas MD Anderson Cancer Center

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

William Small

Loyola University Chicago

View shared research outputs
Top Co-Authors

Avatar

Beth Erickson

Medical College of Wisconsin

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Walter R. Bosch

Washington University in St. Louis

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge