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Dive into the research topics where Robert C. Frazier is active.

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Featured researches published by Robert C. Frazier.


Journal of Clinical Oncology | 2001

Accelerated Treatment of Breast Cancer

Frank A. Vicini; Kathy L. Baglan; Larry L. Kestin; C. Mitchell; Peter Y. Chen; Robert C. Frazier; Greg Edmundson; Neal S. Goldstein; Pamela Benitez; Raywin Huang; A. Martinez

PURPOSE Radiation therapy (RT) restricted to the tumor bed, by means of an interstitial implant, and lasting 4 to 5 days after lumpectomy was prospectively evaluated in early-stage breast cancer patients treated with breast-conserving therapy (BCT). The goals of the study were to determine whether treatment time can be reduced and whether elective treatment of the entire breast is necessary. MATERIALS AND METHODS Between January 1993 and January 2000, 174 cases of early-stage breast cancer were managed with lumpectomy followed by RT restricted to the tumor bed using an interstitial implant. Each brachytherapy patient was matched with one external-beam RT (ERT) patient derived from a reference group of 1,388 patients treated with standard BCT. Patients were matched for age, tumor size, histology, margins of excision, absence of an extensive intraductal component, nodal status, estrogen receptor status, and tamoxifen use. Median follow-up for both the ERT and brachytherapy groups was 36 months. RESULTS No statistically significant differences were noted in the 5-year actuarial rates of ipsilateral breast treatment failure or locoregional failure between ERT and brachytherapy patients (1% v 0%, P =.31 and 2% v 1%, P =.63, respectively). In addition, there were no statistically significant differences noted in rates of distant metastasis (6% v 3%, P =.24), disease-free survival (87% v 91%, P =.55), overall survival (90% v 93%, P =.66), or cause-specific survival (97% v 99%, P =.28). CONCLUSION Accelerated treatment of breast cancer using an interstitial implant to deliver radiation to the tumor bed alone over 4 to 5 days seems to produce 5-year results equivalent to those achieved with conventional ERT. Extended follow-up will be required to determine the long-term efficacy of this treatment approach.


International Journal of Radiation Oncology Biology Physics | 2002

The dose-volume realationship of acute small bowel toxicity from concurrent 5-FU-based chemotherapy and radiation therapy for rectal cancer

Kathy L. Baglan; Robert C. Frazier; Di Yan; Raywin Huang; A. Martinez; J.M. Robertson

Abstract Purpose: A direct relationship between the volume of small bowel irradiated and the degree of acute small bowel toxicity experienced during concurrent 5-fluorouracil (5-FU)-based chemoradiotherapy for rectal carcinoma is well recognized but poorly quantified. This study uses three-dimensional treatment-planning tools to more precisely quantify this dose-volume relationship. Methods and Materials: Forty patients receiving concurrent 5-FU-based chemotherapy and pelvic irradiation for rectal carcinoma had treatment-planning CT scans with small bowel contrast. A median isocentric dose of 50.4 Gy was delivered using a posterior-anterior and opposed lateral field arrangement. Bowel exclusion techniques were routinely used, including prone treatment position on a vacuum bag cradle to allow anterior displacement of the abdominal contents and bladder distension. Individual loops of small bowel were contoured on each slice of the planning CT scan, and a small bowel dose-volume histogram was generated for the initial pelvis field receiving 45 Gy. The volume of small bowel receiving each dose between 5 and 40 Gy was recorded at 5-Gy intervals. Results: Ten patients (25%) experienced Common Toxicity Criteria Grade 3+ acute small bowel toxicity. A highly statistically significant association between the development of Grade 3+ acute small bowel toxicity and the volume of small bowel irradiated was found at each dose level. Specific dose-volume threshold levels were found, below which no Grade 3+ toxicity occurred and above which 50–60% of patients developed Grade 3+ toxicity. The volume of small bowel receiving at least 15 Gy ( V 15 ) was strongly associated with the degree of toxicity. Univariate analysis of patient and treatment-related factors revealed no other significant predictors of severe toxicity. Conclusions: A strong dose-volume relationship exists for the development of Grade 3+ acute small bowel toxicity in patients receiving concurrent 5-FU-based chemoradiotherapy for rectal carcinoma.


International Journal of Radiation Oncology Biology Physics | 2001

The use of high-dose-rate brachytherapy alone after lumpectomy in patients with early-stage breast cancer treated with breast-conserving therapy

Kathy L. Baglan; A. Martinez; Robert C. Frazier; Vijay R. Kini; Larry L. Kestin; Peter Y. Chen; Greg Edmundson; Elizabeth Mele; David A. Jaffray; Frank A. Vicini

PURPOSE We present the preliminary results of our in-house protocol using outpatient high-dose-rate (HDR) brachytherapy as the sole radiation modality following lumpectomy in patients with early-stage breast cancer. METHODS AND MATERIALS Thirty-seven patients with 38 Stage I-II breast cancers received radiation to the lumpectomy cavity alone using an HDR interstitial implant with (192)Ir. A minimum dose of 32 Gy was delivered on an outpatient basis in 8 fractions of 4 Gy to the lumpectomy cavity plus a 1- to 2-cm margin over consecutive 4 days. RESULTS Median follow-up is 31 months. There has been one ipsilateral breast recurrence for a crude failure rate of 2.6% and no regional or distant failures. Wound healing was not impaired in patients undergoing an open-cavity implant. Three minor breast infections occurred, and all resolved with oral antibiotics. The cosmetic outcome was good to excellent in all patients. CONCLUSION In selected patients with early-stage breast cancer, treatment of the lumpectomy cavity alone with outpatient HDR brachytherapy is both technically feasible and well tolerated. Early results are encouraging, however, longer follow-up is necessary before equivalence to standard whole-breast irradiation can be established and to determine the most optimal radiation therapy technique to be employed.


Journal of Clinical Oncology | 2000

Impact of Young Age on Outcome in Patients With Ductal Carcinoma-In-Situ Treated With Breast-Conserving Therapy

Frank A. Vicini; Larry L. Kestin; Neal S. Goldstein; Peter Y. Chen; Jane Pettinga; Robert C. Frazier; Alvaro Martinez

PURPOSE We reviewed our institutions experience treating patients with ductal carcinoma-in-situ (DCIS) with breast-conserving therapy (BCT) to determine the impact of patient age on outcome. PATIENTS AND METHODS From 1980 to 1993, 146 patients were treated with BCT for DCIS. All patients underwent excisional biopsy, and 64% underwent re-excision. All patients received whole-breast irradiation to a median dose of 45 Gy. Ninety-four percent of patients received a boost to the tumor bed, for a median total dose of 60.4 Gy. All slides on every patient were reviewed by one pathologist. The median follow-up period was 7.2 years. RESULTS Seventeen patients developed an ipsilateral local recurrence, for 5- and 10-year actuarial rates of 10.2% and 12.4%, respectively. The 10-year rate of ipsilateral failure was 26.1% in patients younger than 45 years of age versus 8.6% in older patients (P =.03). On multivariate analysis, young age was independently associated with recurrence of the index lesion (true recurrence/marginal miss ¿TR/MM failures), regardless of how it was analyzed (eg, < 45 years of age or as a continuous variable). In addition, young patients had a dramatically higher 10-year rate of invasive TR/MM failures (19.9% v 3.2%). In a separate multivariate analysis for the development of invasive TR/MM failures, only patient age and predominant nuclear grade were independently associated with recurrence. The relationship between excision volume and outcome was analyzed in the 95 patients who underwent re-excision. The 5-year actuarial rate of TR/MM failure was significantly worse only in young patients with smaller (< 40 mL) re-excision volumes (33.3% v 9.1%; P =.02). In a separate multivariate analysis of only these 95 patients (25 of whom were < 45 years of age), the volume of re-excision had the strongest association with outcome (P =.05). Patient age was no longer associated with local recurrence. CONCLUSION These findings suggest that young patients with DCIS have a significantly greater risk of local recurrence after BCT that is independent of other previously defined risk factors. Our data also suggest that the extent of resection may in part be related to the less optimal results that are observed in these patients.


Cancer | 1999

Defining Biochemical Cure for Prostate Carcinoma Patients Treated with External Beam Radiation Therapy

Larry L. Kestin; Frank A. Vicini; Ellen L. Ziaja; Jannifer S. Stromberg; Robert C. Frazier; A. Martinez

The authors retrospectively reviewed their institutions long term experience with conventional external beam radiation therapy (RT) for localized prostate carcinoma to identify criteria associated with long term biochemical cure.


International Journal of Radiation Oncology Biology Physics | 1999

Mammographic, pathologic, and treatment-related factors associated with local recurrence in patients with early-stage breast cancer treated with breast conserving therapy

Vijay R. Kini; Frank A. Vicini; Robert C. Frazier; Sandra J. Victor; Kathryn Wimbish; A. Martinez

BACKGROUND We retrospectively reviewed our institutions experience treating early-stage breast cancer patients with breast conserving therapy (BCT) to determine clinical, pathologic, mammographic, and treatment-related factors associated with outcome. METHODS Between January 1980 and December 1987, 400 cases of Stage I and II breast cancer were managed with BCT at William Beaumont Hospital, Royal Oak, Michigan. All patients underwent at least an excisional biopsy. Radiation treatment consisted of delivering 45-50 Gy to the whole breast, followed by a boost to the tumor bed to at least 60 Gy in all patients. The median follow-up in the 292 surviving patients is 118 months. Multiple clinical, pathologic, mammographic, and treatment-related factors were analyzed for an association with local recurrence and survival. RESULTS A total of 37 local recurrences developed in the treated breast, for a 5- and 10-year actuarial rate of 4% and 10%, respectively. On univariate analysis, patient age < or =35 years (25% vs. 7%, p = 0.004), and positive surgical margins (17% vs. 6%, p = 0.018) were associated with an increased risk of local recurrence at 10 years. On multivariate analysis, only age < or = 35 years remained significant. A subset analysis of 214 patients with evaluable mammographic findings was performed. On univariate analysis, age < or = 35 years (38% vs. 8%, p = 0.0029) and the presence of calcifications on preoperative mammography (22% vs. 6%, p = 0.0016) were associated with an increased risk of local recurrence. On multivariate analysis, both of these factors remained significant. The presence of calcifications on preoperative mammography did not affect the rates of overall survival, disease-free survival, and cause-specific survival. CONCLUSION In patients with early-stage breast cancer treated with BCT, age < or = 35 years and calcifications on preoperative mammography appear to be associated with an increased risk of local recurrence.


Annals of Surgery | 2000

Mammographically detected ductal carcinoma in situ treated with conservative surgery with or without radiation therapy: patterns of failure and 10-year results.

Larry L. Kestin; Neal S. Goldstein; Alvaro Martinez; Murray Rebner; Mamtha Balasubramaniam; Robert C. Frazier; John T. Register; Jane Pettinga; Frank A. Vicini

OBJECTIVE The authors reviewed their institutions experience treating mammographically detected ductal carcinoma in situ (DCIS) of the breast with breast-conserving therapy (BCT) to determine 10-year rates of local control and survival, patterns of failure, and factors associated with outcome. SUMMARY BACKGROUND DATA From January 1980 to December 1993, 177 breasts in 172 patients were treated with BCT for mammographically detected DCIS of the breast at William Beaumont Hospital, Royal Oak, Michigan. METHODS All patients underwent an excisional biopsy, and 65% were reexcised. Thirty-one breasts (18%) were treated with excision alone, whereas 146 breasts (82%) received postoperative radiation therapy (RT). All patients undergoing RT received whole-breast irradiation to a median dose of 50.0 Gy. One hundred thirty-six (93%) received a boost to the tumor bed for a median total dose of 60.4 Gy. Median follow-up was 5.9 years for the lumpectomy alone group and 7.2 years for the lumpectomy + RT group. RESULTS In the entire population, 15 patients had an ipsilateral breast recurrence. The 5- and 10-year actuarial rates of ipsilateral breast recurrence were 7.8% and 7.8% for lumpectomy alone and 8.0% and 9.2% for lumpectomy + RT, respectively. Eleven of the 15 recurrences developed within or immediately adjacent to the lumpectomy cavity and were designated as true recurrences or marginal misses (TMM). Four recurred elsewhere in the breast. Eleven of the 15 recurrences were invasive, whereas 4 were pure DCIS. Only one patient died of disease, yielding 5- and 10-year actuarial cause-specific survival rates of 100% and 99.2%, respectively. Eleven patients were diagnosed with subsequent contralateral breast cancer, yielding 5- and 10-year actuarial rates of 5.1% and 8.3%, respectively. Clinical, pathologic, and treatment-related factors were analyzed for an association with ipsilateral breast failure or TR/MM. No factors were significantly associated with ipsilateral breast failure. In the entire population, the omission of RT and younger age at diagnosis were significantly associated with TR/MM. Patients younger than 45 years at diagnosis had a significantly higher rate of TR/MM in both the lumpectomy + RT and lumpectomy alone groups. None of the 37 patients who received a postexcisional mammogram had an ipsilateral breast failure versus 15 in the patients who did not receive a postexcisional mammogram. CONCLUSIONS Patients diagnosed with mammographically detected DCIS of the breast appear to have excellent 100-year rates of local control and overall survival when treated with BCT. These results suggest that the use of RT reduces the risk of local recurrence and that patients diagnosed at a younger age have a higher rate of local recurrence with or without the use of postoperative RT.


American Journal of Clinical Oncology | 2001

Impact of boost technique on outcome in early-stage breast cancer patients treated with breast-conserving therapy

Robert C. Frazier; Larry L. Kestin; Vijay R. Kini; Alvaro Martinez; Peter Y. Chen; Kathy L. Baglan; Frank A. Vicini

We reviewed our institution’s experience treating early-stage breast cancer patients with breast-conserving therapy (BCT) to determine the impact of boost technique on outcome. A total of 552 patients with stage I and II breast cancer were managed with BCT. All patients were treated with a partial mastectomy and radiation therapy (RT). RT consisted of 45 Gy to 50 Gy external beam irradiation to the whole breast followed by a boost to the tumor bed using either electrons (232 patients), photons (15 patients), or an interstitial implant (316 patients). Local control and cosmetic outcome was compared among three patient groups based on the type of boost used. Forty-one patients had a recurrence of cancer in the treated breast for 5-, 10-, and 13-year actuarial local recurrence rates of 2.8%, 7.5%, and 11.2%, respectively. There were no significant differences in the local recurrence rates or cosmetic outcome using electrons, photons, or an interstitial implant. On multivariate analysis, only young age and margin status were associated with local recurrence. Stage I and II breast cancer patients undergoing BCT can be effectively managed with electron, photon, or interstitial implant boost techniques. Long-term local control and cosmetic outcome are excellent regardless of which boost technique is used.


Radiotherapy and Oncology | 2000

98 The use of high dose rate brachytherapy alone after lumpectomy in patients with early stage breast cancer treated with breast conserving therapy

Kathy L. Saglan; Vijay R. Kini; Robert C. Frazier; Larry L. Kestin; Peter Y. Chen; Greg Edmundson; Elizabeth Mele; David A. Jaffray; Alvaro Martinez; Frank A. Vicini

Purpose: We present the preliminary results of our in-house protocol using outpatient high-dose-rate (HDR) brachytherapy as the sole radiation modality following lumpectomy in patients with early-stage breast cancer. Methods and Materials: Thirty-seven patients with 38 Stage I‐II breast cancers received radiation to the lumpectomy cavity alone using an HDR interstitial implant with 192 Ir. A minimum dose of 32 Gy was delivered on an outpatient basis in 8 fractions of 4 Gy to the lumpectomy cavity plus a 1- to 2-cm margin over consecutive 4 days. Results: Median follow-up is 31 months. There has been one ipsilateral breast recurrence for a crude failure rate of 2.6% and no regional or distant failures. Wound healing was not impaired in patients undergoing an open-cavity implant. Three minor breast infections occurred, and all resolved with oral antibiotics. The cosmetic outcome was good to excellent in all patients. Conclusion: In selected patients with early-stage breast cancer, treatment of the lumpectomy cavity alone with outpatient HDR brachytherapy is both technically feasible and well tolerated. Early results are encouraging, however, longer follow-up is necessary before equivalence to standard whole-breast irradiation can be established and to determine the most optimal radiation therapy technique to be employed.


International Journal of Radiation Oncology Biology Physics | 2000

Intensity modulation to improve dose uniformity with tangential breast radiotherapy : Initial clinical experience

Larry L. Kestin; Michael B. Sharpe; Robert C. Frazier; Frank A. Vicini; Di Yan; Richard C. Matter; A. Martinez; John Wong

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