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Featured researches published by Francisco Perera.


The New England Journal of Medicine | 2010

Long-Term Results of Hypofractionated Radiation Therapy for Breast Cancer

Timothy J. Whelan; Jean-Philippe Pignol; Mark N. Levine; Jim A. Julian; Robert MacKenzie; Sameer Parpia; Wendy Shelley; Laval Grimard; Julie Bowen; Francisco Perera; Anthony Fyles; Ken Schneider; Sunil P.P. Gulavita; Carolyn R. Freeman

BACKGROUNDnThe optimal fractionation schedule for whole-breast irradiation after breast-conserving surgery is unknown.nnnMETHODSnWe conducted a study to determine whether a hypofractionated 3-week schedule of whole-breast irradiation is as effective as a 5-week schedule. Women with invasive breast cancer who had undergone breast-conserving surgery and in whom resection margins were clear and axillary lymph nodes were negative were randomly assigned to receive whole-breast irradiation either at a standard dose of 50.0 Gy in 25 fractions over a period of 35 days (the control group) or at a dose of 42.5 Gy in 16 fractions over a period of 22 days (the hypofractionated-radiation group).nnnRESULTSnThe risk of local recurrence at 10 years was 6.7% among the 612 women assigned to standard irradiation as compared with 6.2% among the 622 women assigned to the hypofractionated regimen (absolute difference, 0.5 percentage points; 95% confidence interval [CI], -2.5 to 3.5). At 10 years, 71.3% of women in the control group as compared with 69.8% of the women in the hypofractionated-radiation group had a good or excellent cosmetic outcome (absolute difference, 1.5 percentage points; 95% CI, -6.9 to 9.8).nnnCONCLUSIONSnTen years after treatment, accelerated, hypofractionated whole-breast irradiation was not inferior to standard radiation treatment in women who had undergone breast-conserving surgery for invasive breast cancer with clear surgical margins and negative axillary nodes. (ClinicalTrials.gov number, NCT00156052.)


Journal of Clinical Oncology | 2013

Interim Cosmetic and Toxicity Results From RAPID: A Randomized Trial of Accelerated Partial Breast Irradiation Using Three-Dimensional Conformal External Beam Radiation Therapy

Ivo A. Olivotto; Timothy J. Whelan; Sameer Parpia; Do-Hoon Kim; Tanya Berrang; Pauline T. Truong; Iwa Kong; Brandy Cochrane; Alan Nichol; Isabelle Roy; Isabelle Germain; Mohamed Akra; Melanie Reed; Anthony Fyles; Theresa Trotter; Francisco Perera; W. Beckham; Mark N. Levine; Jim A. Julian

PURPOSEnTo report interim cosmetic and toxicity results of a multicenter randomized trial comparing accelerated partial-breast irradiation (APBI) using three-dimensional conformal external beam radiation therapy (3D-CRT) with whole-breast irradiation (WBI).nnnPATIENTS AND METHODSnWomen age > 40 years with invasive or in situ breast cancer ≤ 3 cm were randomly assigned after breast-conserving surgery to 3D-CRT APBI (38.5 Gy in 10 fractions twice daily) or WBI (42.5 Gy in 16 or 50 Gy in 25 daily fractions ± boost irradiation). The primary outcome was ipsilateral breast tumor recurrence (IBTR). Secondary outcomes were cosmesis and toxicity. Adverse cosmesis was defined as a fair or poor global cosmetic score. After a planned interim cosmetic analysis, the data, safety, and monitoring committee recommended release of results. There have been too few IBTR events to trigger an efficacy analysis.nnnRESULTSnBetween 2006 and 2011, 2,135 women were randomly assigned to 3D-CRT APBI or WBI. Median follow-up was 36 months. Adverse cosmesis at 3 years was increased among those treated with APBI compared with WBI as assessed by trained nurses (29% v 17%; P < .001), by patients (26% v 18%; P = .0022), and by physicians reviewing digital photographs (35% v 17%; P < .001). Grade 3 toxicities were rare in both treatment arms (1.4% v 0%), but grade 1 and 2 toxicities were increased among those who received APBI compared with WBI (P < .001).nnnCONCLUSIONn3D-CRT APBI increased rates of adverse cosmesis and late radiation toxicity compared with standard WBI. Clinicians and patients are cautioned against the use of 3D-CRT APBI outside the context of a controlled trial.


Clinical Cancer Research | 2006

Serial Plasma Osteopontin Levels Have Prognostic Value in Metastatic Breast Cancer

Vivien Bramwell; Gordon S. Doig; Alan B. Tuck; Sylvia M. Wilson; Katia Tonkin; Anna Tomiak; Francisco Perera; Theodore A. Vandenberg; Ann F. Chambers

Purpose: Osteopontin is a malignancy-associated protein measurable in blood and tumor tissue. To evaluate its prognostic value in advanced disease, we conducted a prospective clinical study measuring serial osteopontin plasma levels in women with metastatic breast cancer throughout the course of their disease. Experimental Design: One hundred fifty-eight women with newly diagnosed metastatic breast cancer were enrolled in the study. Plasma osteopontin was measured using our validated ELISA, at baseline and every 3 to 12 weeks during and after therapy until death. Multivariate time-dependent survival analyses were conducted using models that right censored patient outcomes 3, 6, and 12 months after the last known osteopontin measurement. Results: Osteopontin was measured in 1,378 samples (median, 9 per patient). Ninety-nine patients had elevated baseline osteopontin (median, 177 ng/mL; range, 1-2,648 ng/mL). In univariate analysis, elevated baseline osteopontin was associated with short survival (P = 0.02). In a multivariate model incorporating standard prognostic factors, baseline osteopontin was significantly associated with survival duration (relative risk, 1.001; P = 0.038). Metastasis-free interval, visceral metastases, and Eastern Cooperative Oncology Group status 2 to 4 also retained significance. In a multivariate model incorporating standard prognostic factors and changes in sequential osteopontin levels, an osteopontin increase of >250 ng/mL at any time was the variable with the most prognostic value for poor survival (relative risk, 3.26; P = 0.0003), and poor Eastern Cooperative Oncology Group status also retained significance. Conclusions: This is the first study to show that in women with metastatic breast cancer, increases in osteopontin levels over time are strongly associated with poor survival. Sequential monitoring of osteopontin may have use in making treatment decisions for these patients.


Journal of Surgical Oncology | 1997

Local resection and brachytherapy confined to the lumpectomy site for early breast cancer: A pilot study

Francisco Perera; Jay Engel; Ronald Holliday; Leslie Scott; Murray Girotti; David Girvan; Frank Chisela; Varagur Venkatesan

The commonest site of local breast recurrence after breast conservation surgery is the primary tumor bed. We have tested the feasibility of outpatient high dose rate brachytherapy to the primary tumor bed as the only radiation. Our technique relies on the placement of surgical clips to mark the tumor bed.


International Journal of Radiation Oncology Biology Physics | 2003

Patterns of Breast Recurrence in a Pilot Study of Brachytherapy Confined to the Lumpectomy Site for Early Breast Cancer with Six Years' Minimum Follow-up

Francisco Perera; Edward Yu; Jay Engel; Ronald Holliday; Leslie Scott; Frank Chisela; Varagur Venkatesan

PURPOSEnIn this pilot study of high-dose-rate brachytherapy to the lumpectomy site as the sole radiation, ipsilateral and contralateral breast recurrences are documented with specific attention to the location of recurrence relative to the lumpectomy site.nnnMETHODSnBetween March 1992 and January 1996, 39 patients with T1 (32 patients) and T2 breast cancers received 37.2 Gy in 10 fractions (b.i.d.) over 1 week prescribed to a volume encompassing the surgical clips. Thirteen received adjuvant tamoxifen, and 4 received chemotherapy. Follow-up included annual bilateral mammograms and clinical breast examination every 3 to 6 months. Whereas 13 patients had intraoperative implantation of the lumpectomy site, 26 had postoperative implantation. The latter group and 7 of the former group had surgical clips marking the lumpectomy site, which allowed estimates of the distance of any ipsilateral breast recurrence from the lumpectomy site, using the mediolateral and cranio-caudad mammographic views.nnnRESULTSnAt a median follow-up of 91 months, 33 women are alive, 4 have died of disease, and 2 have died of other causes. The 5-year actuarial rate of ipsilateral breast recurrence was 16.2%. Of 6 ipsilateral recurrences, 2 occurred within the lumpectomy site (in-field recurrences). One of the 2 patients had a 1-mm microscopic margin at initial diagnosis; the recurrence was a 3.5-mm microscopic focus of duct carcinoma in situ. The other patient had a 1.5-cm, high-grade infiltrating mammary carcinoma with no residual at wider resection at first diagnosis; the 5-mm invasive recurrence was also of high grade. Four women developed invasive recurrences at least 1.6 cm or more from the lumpectomy site (out-of-field recurrences). Two of these women had gross multifocal recurrences with two cancers in each patient; 1 of the 2 patients had an extensive intraductal component at initial diagnosis. The estimated nearest distances between the out-of-field recurrences and the surgical clips were 1.6, 5.5, 7.7, and 12.0 cm. All ipsilateral breast recurrences were salvaged by mastectomy (4 patients) or by repeat lumpectomy (2 patients) and whole-breast radiation. The interval postdiagnosis to ipsilateral recurrence ranged from 20 months to 58 months. There were two contralateral breast recurrences at intervals of 34 and 36 months; 1 of these patients also had a multifocal, ipsilateral recurrence at 58 months, as previously described. Among patients with any breast recurrence, 1 patient had a family history of prostate cancer; there was no family history of breast or ovarian cancer. Of 17 patients who received adjuvant systemic therapy, only 1 had a breast recurrence.nnnCONCLUSIONSnIn this pilot study, breast recurrences outside of the lumpectomy site were the predominant pattern of recurrence.


International Journal of Radiation Oncology Biology Physics | 1998

Preoperative radiation with concurrent 5-fluorouracil continuous infusion for locally advanced unresectable rectal cancer

Gregory M.M Videtic; B.J. Fisher; Francisco Perera; G. Bauman; Walter I Kocha; Marianne Taylor; Mark Vincent; E.A Plewes; C.Jay Engel; L. Stitt

BACKGROUND AND PURPOSEnTo determine the percentage of complete responders and the resectability rate for patients with locally advanced carcinoma of the rectum treated by 5-fluorouracil (5-FU) infusional chemotherapy and pelvic radiation.nnnMATERIALS AND METHODSnBetween October 1992 and June 1996, 29 patients with a diagnosis of locally advanced unresectable rectal cancer received preoperative 5 FU by continuous intravenous infusion at a dose of 225 mg/m2/day concurrent with pelvic radiation (median 54 Gy/28 fractions). All patients were clinical stage T4 on the bases of organ invasion or tumor fixation. Median time for surgical resection was 6 weeks.nnnRESULTSnMedian follow-up for the group was 28 months (range 5-57 months). Six patients were felt to be persistently unresectable or developed distant metastases and did not undergo surgical resection. Of the 29 patients, 23 proceeded to surgery, 18 were resectable for cure, 13 by abdominoperineal resection, 3 by anterior resection and 2 by local excision. Of the 29 patients, 4 (13%) had a complete response, and 90% were clinically downstaged. Of the 18 resected patients, 1 has died of his disease, 17 are alive, and 15 disease-free. The regimen was well tolerated; there was only one treatment-related complication, a wound dehiscence.nnnCONCLUSIONnThe combination of 5 FU infusion and pelvic radiation in the management of locally advanced rectal cancer is well tolerated and provides a baseline for comparison purposes with future combinations of newer systemic agents and radiation.


International Journal of Radiation Oncology Biology Physics | 1997

Extracapsular axillary node extension in patients receiving adjuvant systemic therapy: An indication for radiotherapy?

Barbara Fisher; Francisco Perera; A.L. Cooke; Abiola Opeitum; A.R. Dar; Varagur Venkatesan; Larry Stitt; J.S. Radwan

PURPOSEnThis is a retrospective review into the patterns of failure of 82 patients with Stage II or III breast cancer who had extracapsular extension (ECE) of axillary nodal metastases and who received systemic chemotherapy or hormonal therapy without loco-regional radiation.nnnMETHODS AND MATERIALSnThe clinical records of patients with axillary node positive (T1-T3, N1, 2) Stage II or III breast cancer seen at the London Regional Cancer Centre between 1980-1989 were reviewed. Patients were identified who underwent segmental mastectomy with axillary node dissection or modified radical mastectomy and received adjuvant chemotherapy or tamoxifen but did not undergo loco-regional radiation. Eighty-two patients within this group had pathologic evidence of extracapsular axillary node extension (ECE). For 45 of these patients the extension was extensive, and for the remaining 37 it was microscopic. This ECE-positive group was compared to a subgroup of 172 patients who did not have pathologic evidence of extracapsular axillary node extension but had metastatic carcinoma confined within the nodal capsule.nnnRESULTSnMedian age of the 82 ECE-positive patients was 56 years. Twenty-five patients had had a segmental mastectomy, the remainder a modified radical mastectomy. Median actuarial survival was 60 months, with a median disease-free and loco-regional failure-free survival of 38 months. Seventy-eight percent of these patients developed a recurrence, which was loco-regional in 60% (21% local, 21% regional, 2% local and regional, and 16% loco-regional and metastatic). There was a 36% recurrence rate in intact breast, 14% the chest wall following modified radical mastectomy, 7% relapsed in the axilla, 12% in supraclavicular nodes, and 1% in the internal mammary nodes. A comparison of the 82 ECE-positive patients with a group of 172 ECE-negative patients determined that there was a statistically significant difference between the two groups in terms of survival (overall and disease-free) and loco-regional recurrence. Univariate analysis of the entire 254 node-positive patient group revealed extracapsular nodal extension (ECE) to be a prognostically significant factor for actuarial and disease-free survival as well as for loco-regional failure, but ECE did not remain an independently prognostic factor after multivariate analysis. Segmental mastectomy, positive resection margins, and ER negative status increased the risk of loco-regional recurrence within the ECE-positive group.nnnCONCLUSIONSnExtracapsular axillary node extension is a prognostically significant factor for actuarial survival, disease-free survival, and loco-regional failure but not independent of other adverse prognostic factors. It is a marker for increased loco-regional recurrence associated with doubling of breast, chest wall, and supraclavicular recurrence rates. The risk of axillary relapse in patients who have had an adequate level I and II axillary dissection but demonstrate extracapsular extension is low (7%). We recommend breast/chest wall and supraclavicular radiation for all patients with pathologic evidence of such extranodal extension who have had a level I and II axillary dissection regardless of the number of positive axillary nodes. Axillary irradiation should be considered for patients who have had only an axillary sampling or level I axillary dissection.


International Journal of Radiation Oncology Biology Physics | 1995

METHOD OF LOCALIZATION AND IMPLANTATION OF THE LUMPECTOMY SITE FOR HIGH DOSE RATE BRACHYTHERAPY AFTER CONSERVATIVE SURGERY FOR T1 AND T2 BREAST CANCER

Francisco Perera; Frank Chisela; Jay Engel; Varagur Venkatesan

PURPOSEnThis article describes our technique of localization and implantation of the lumpectomy site of patients with T1 and T2 breast cancer. Our method was developed as part of our Phase I/II pilot study of high dose rate (HDR) brachytherapy alone after conservative surgery for early breast cancer.nnnMETHODS AND MATERIALSnIn March 1992, we started a pilot study of HDR brachytherapy to the lumpectomy site as the sole radiotherapy after conservative surgery for clinical T1 or T2 invasive breast cancer. Initially, the protocol required intraoperative placement of the interstitial needles at the time of definitive surgery to the breast. The protocol was then generalized to allow the implantation of the lumpectomy site after definitive surgery to the breast, either at the time of subsequent axillary nodal dissection or postoperatively. To date, five patients have been implanted intraoperatively at the time of definitive breast surgery. Twelve patients were implanted after definitive breast surgery, with 7 patients being done at the time of axillary nodal dissection and 5 patients postoperatively. We devised a method of accurately localizing and implanting the lumpectomy site after definitive breast surgery. The method relies on the previous placement of surgical clips by the referring surgeon to mark the lumpectomy site. For each patient, a breast mold is made with radio-opaque angiocatheters taped onto the mold in the supero-inferior direction. A planning CT scan is then obtained through the lumpectomy site. The volume of the lumpectomy site, the number of implant planes necessary, and the orientation of the implants are then determined from the CT scan. The angiocatheters provide a reference grid on the CT films to locate the entry and exit points of the interstitial needles on the plastic mold. The entry and exit points for reference needles are then transferred onto the patients skin enabling implantation of the lumpectomy site. Needle positions with respect to the lumpectomy site are then verified using simulator radiographs.nnnRESULTSnEight double plane implants and four single plane implants have been done using this method. Five implants were done using direct visualization. It has not been necessary to reorient the implant in any of the patients. If not for the presence of surgical clips, the size of the lumpectomy site cannot be separated from the surrounding normal breast tissue.nnnCONCLUSIONnThis technique is an accurate way to localize the lumpectomy site for HDR brachytherapy.


Journal of Clinical Oncology | 2012

Prospective Study of 2-[18F]Fluorodeoxyglucose Positron Emission Tomography in the Assessment of Regional Nodal Spread of Disease in Patients With Breast Cancer: An Ontario Clinical Oncology Group Study

Kathleen I. Pritchard; Jim A. Julian; Claire Holloway; David R. McCready; Karen Y. Gulenchyn; Ralph George; Nicole Hodgson; Peter J. Lovrics; Francisco Perera; Leela Elavathil; Frances P. O'Malley; Nancy Down; Audley Bodurtha; Wendy Shelley; Mark N. Levine

PURPOSEn2-[(18)F]fluorodeoxyglucose (FDG) positron emission tomography (PET) is potentially useful in assessing lymph nodes and detecting distant metastases in women with primary breast cancer.nnnPATIENTS AND METHODSnWomen diagnosed with operable breast cancer within 3 months underwent FDG-PET at one of five Ontario study centers followed by axillary lymph node assessment (ALNA) consisting of sentinel lymph node biopsy (SLNB) alone if sentinel lymph nodes (SLNs) were negative, SLNB with axillary lymph node dissection (ALND) if SLNB or PET was positive, or ALND alone if SLNs were not identified.nnnRESULTSnBetween January 2005 and March 2007, 325 analyzable women entered this study. Sentinel nodes were found for 312 (96%) of 325 women and were positive for tumor in 90 (29%) of 312. ALND was positive in seven additional women. Using ALNA as the gold standard, sensitivity for PET was 23.7% (95% CI, 15.9% to 33.6%), specificity was 99.6% (95% CI, 97.2% to 99.9%), positive predictive value was 95.8% (95% CI, 76.9% to 99.8%), negative predictive value was 75.4% (95% CI, 70.1% to 80.1%), and prevalence was 29.8% (95% CI, 25.0% to 35.2%). Using logistic regression, tumor size was predictive for prevalence of tumor in the axilla and for PET sensitivity. PET scan was suspicious for distant metastases in 13 patients; three (0.9%) were confirmed as metastatic disease and 10 (3.0%) were false positive.nnnCONCLUSIONnFDG-PET is not sufficiently sensitive to detect positive axillary lymph nodes, nor is it sufficiently specific to appropriately identify distant metastases. However, the very high positive predictive value (96%) suggests that PET when positive is indicative of disease in axillary nodes, which may influence surgical care.


International Journal of Radiation Oncology Biology Physics | 1999

ANALYSIS OF THE CLINICAL BENEFIT OF 5-FLUOROURACIL AND RADIATION TREATMENT IN LOCALLY ADVANCED PANCREATIC CANCER

Barbara Fisher; Francisco Perera; Walter Kocha; Anna Tomiak; Marianne Taylor; Mark Vincent; Glenn Bauman

PURPOSEnTo assess the palliative benefit of 5-fluorouracil (5-FU) and radiotherapy in patients with surgically unresectable localized pancreatic cancer.nnnMETHODS AND MATERIALSnTwenty-five patients with locally advanced surgically unresectable symptomatic pancreatic cancer received 5-FU chemotherapy and local radiation therapy. They were retrospectively reviewed in regard to their clinical benefit response (a composite of measurement of pain assessment, weight, and Karnofsky performance status [KPS]), as well as radiological response, time to progression, and overall survival.nnnRESULTSnMedian survival for the 25 patients was 9 months and median progression-free survival was 6 months. Thirty-two percent of patients survived in excess of 1 year. Analgesic requirements increased >50% in 2 patients and KPS deteriorated in 10 patients. Of the 13 remaining patients, 2 sustained a >7% weight loss and 2 gained weight post-treatment. Six patients improved in one parameter of analgesic consumption, weight loss or KPS without deteriorating in any others. Thus, the clinical benefit response index for 5-FU-radiation was 6/25 (24%). In terms of tumor response, 8 patients (44%) demonstrated a reduction in tumor volume post-treatment, 4 of whom (22%) experienced a >50% reduction. Four additional patients had radiologically stable disease.nnnCONCLUSIONnIn this retrospective analysis, the clinical benefit response index for 5-FU-radiation was 24%, a value similar to the 23.8% reported for single agent gemcitabine. The median survival of 7 months was also similar to the 5.65 months reported for gemcitabine. The radiological partial response rate of 22% and the 1-year survival of 32% were higher for 5-FU-radiation than the reported values for gemcitabine. A randomized trial would be necessary to compare 5-FU-radiation to gemcitabine directly; however, from this review it did not appear that the overall palliative benefit of 5-FU-radiation was inferior to gemcitabine.

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Edward Yu

University of Western Ontario

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Olga Vujovic

University of Western Ontario

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Larry Stitt

University of Western Ontario

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George Rodrigues

University of Western Ontario

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Varagur Venkatesan

University of Western Ontario

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A. Rashid Dar

University of Western Ontario

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Barbara Fisher

University of Western Ontario

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Jawaid Younus

University of Western Ontario

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L. Stitt

London Health Sciences Centre

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