Preliminary Results in 173 Breast Cancer Patients Treated with Post-Lumpectomy MammoSite Single-Lumen Brachytherapy or Multi-Catheter Brachytherapy.

The objective of this study was to report our single-institution results with MammoSite and multi-catheter brachytherapy. Between February 2003 and January 2009, 173 women with unifocal pathological Tis, T1, or T2 (up to 30 mm), N0 or N1 carcinomas of the breast were treated with post-lumpectomy brachytherapy to 34 Gy in 10 fractions over 5-10 days. We treated 137 patients with MammoSite single-lumen balloon brachytherapy, and 36 patients with multi-catheter brachytherapy. Patients with small and/or nonspherical lumpectomy cavities were usually treated with multi-catheter brachytherapy using 4-12 interstitial catheters. Median follow-up was 33 months. Three-year ipsilateral breast tumor control, disease-free, and overall survival rates for MammoSite brachytherapy were 100%, 100%, and 99%, respectively. Similar rates were obtained with multi-catheter brachytherapy. Minimum distances from the planning target volume for plan evaluation to a rib were 10 ± 8 mm (mean ± standard deviation) and 8 ± 4 mm (mean ± standard deviation) for MammoSite brachytherapy and multi-catheter brachytherapy, respectively (p = 0.48). Maximum rib doses were 101 ± 14% (mean ± standard deviation) and 74 ± 10% (mean ± standard deviation) of the prescribed dose for MammoSite brachytherapy and multi-catheter brachytherapy, respectively (p = 0.001). Multi-catheter brachytherapy results in more conformal radiation dose delivery and a significantly lower rib dose than MammoSite single-lumen brachytherapy. Long-term follow-up is needed to determine if the delivery of a lower radiation dose to the ribs will translate into a lower incidence of rib pain and fractures.

A Contura catheter offers dosimetric advantages over a MammoSite catheter that increase the applicability of accelerated partial breast irradiation.

PURPOSE: The purpose of this study was to determine whether a Contura catheter (SenoRx, Inc, Aliso Viejo, CA) can increase the applicability of accelerated partial breast irradiation. METHODS AND MATERIALS: One hundred eighty-two women with early stage breast carcinomas were treated with postlumpectomy brachytherapy using a Contura multilumen catheter (n=45) or a MammoSite single-lumen catheter (Cytyc Corp, Marlborough, MA) (n=137). Hypothetical MammoSite catheter treatment plans were created for the Contura patients. Treatment planning goals were to (1) avoid a radiation "hot spot" in the skin and (2) have only a small air/fluid pocket next to the balloon. RESULTS: The median followup was 16 months. Eighty-nine percent (40 of 45) of Contura plans satisfied both treatment planning goals vs. only 36% (16 of 45) of MammoSite plans (p<0.0001). A Contura catheter did not require explantation in 16% (7 of 45) of patients where balloon-to-skin spacing was only 3-6mm and 11% (5 of 45) of patients where there was an air/fluid pocket >10% of the planning target volume for plan evaluation (PTV_EVAL). A MammoSite catheter was explanted in 10% of cases where the minimum balloon-to-skin distance was <7mm and in 13% of cases where there was a large air/fluid pocket next to the balloon. Our incidence rates of acute toxicity with a Contura catheter were similar to those with a MammoSite catheter. CONCLUSIONS: A Contura catheter provides important dosimetric advantages over a MammoSite catheter and does not require explantation in cases where balloon-to-skin spacing is only 3-6mm or an air/fluid pocket next to the balloon is >10% of PTV_EVAL.

Polyethylene glycol hydrogel rectal spacer implantation in patients with prostate cancer undergoing combination high-dose-rate brachytherapy and external beam radiotherapy.

PURPOSE: To present rectal toxicity rates in patients administered a polyethylene glycol (PEG) hydrogel rectal spacer in conjunction with combination high-dose-rate brachytherapy and external beam radiotherapy. METHODS AND MATERIALS: Between February 2010 and April 2015, 326 prostate carcinoma patients underwent combination high-dose-rate brachytherapy of 16 Gy (average dose 15.5 Gy; standard deviation [SD] = 1.6 Gy) and external beam radiotherapy of 59.4 Gy (average dose 60.2 Gy; SD = 2.9 Gy). In conjunction with the radiation therapy regimen, each patient was injected with 10 mL of a PEG hydrogel in the anterior perirectal fat space. The injectable spacer (rectal spacer) creates a gap between the prostate and the rectum. The rectum is displaced from the radiation field, and rectal dose is substantially reduced. The goal is a reduction in rectal radiation toxicity. Clinical efficacy was determined by measuring acute and chronic rectal toxicity using the National Cancer Center Institute Common Terminology Criteria for Adverse Events v4.0 grading scheme. RESULTS: Median followup was 16 months. The mean anterior-posterior separation achieved was 1.6 cm (SD = 0.4 cm). Rates of acute Grade 1 and 2 rectal toxicity were 37.4% and 2.8%, respectively. There were no acute Grade 3/4 toxicities. Rates of late Grade 1, 2, and 3 rectal toxicity were 12.7%, 1.4%, and 0.7%, respectively. There were no late Grade 4 toxicities. CONCLUSIONS: PEG rectal spacer implantation is safe and well tolerated. Acute and chronic rectal toxicities are low despite aggressive dose escalation.

Four-year outcomes of hypofractionated high-dose-rate prostate brachytherapy and external beam radiotherapy.

PURPOSE: High-dose-rate (HDR) brachytherapy boost in prostate cancer allows dose escalation and delivery of higher biologically effective dose (BED). We evaluated the outcomes of intensity-modulated radiation therapy (IMRT) and HDR boost in a community setting. METHODS AND MATERIALS: Between July 2003 and April 2008, 148 patients with prostate cancer were treated at Cancer Center of Irvine using two transperineal implants performed 1 week apart (22Gy delivered in four fractions divided between two insertions and delivered twice daily), followed by IMRT (50.4Gy). Hormonal therapy was given for 1 year to all patients with Gleason score of 8 or higher. RESULTS: Patient characteristics are as follows: median age at treatment, 71 years; American Joint Committee on Cancer Group IIB, 53%; Gleason score of 7, 41%; and Gleason score of 8 or higher, 14%. Median followup was 49 months, and median prostate-specific antigen (PSA) nadir was 0.15ng/mL. The 4-year actuarial biochemical disease-free survival (bDFS) was 96.8/81% by Phoenix/PSA lower than 0.5ng/mL criteria. According to National Comprehensive Cancer Center Clinical Practice Guidelines-defined recurrence risk groups, 4-year bDFS for low risk was 100/92.9%, intermediate risk was 100/86.7%, and high risk was 94/75.4% by Phoenix/PSA lower than 0.5ng/mL criteria. No statistically significant difference in bDFS was detected by either failure criteria based on risk group, lymph node risk, or initial PSA. Treatment was well tolerated. Subacute/late genitourinary and gastrointestinal toxicities were limited to 10% and 5%, respectively of all patients. CONCLUSIONS: Prostate IMRT plus HDR brachytherapy boost was well tolerated with appropriate PSA response and bDFS at 4 years, demonstrated in a community setting. This treatment schema provides a high BED, comparable with hypofractionated prostate regimens previously reported in the literature. Higher BED delivery should be explored in further dose escalation studies.

Cross-linked hyaluronan gel improves the quality of life of prostate cancer patients undergoing radiotherapy.

PURPOSE: To test the hypothesis that cross-linked hyaluronan gel (Hylaform) does not affect the quality of life (QOL) of prostate cancer patients undergoing radiotherapy. METHODS AND MATERIALS: Thirty-five patients with early stage prostate cancer underwent high-dose-rate brachytherapy to 2200 cGy and intensity modulated radiation therapy to 5040 cGy on a prospective study. Thirty patients received a single transperineal injection of 9-mL Hylaform between the prostate and rectum under transrectal ultrasound guidance immediately before the start of radiotherapy. Hylaform increased the separation between the prostate and rectum by 6-19 mm (median, 13 mm) at the start of radiotherapy. Five patients did not receive Hylaform and served as controls. We assessed gastrointestinal-related QOL using Expanded Prostate Cancer Index Composite Bowel Bother scores immediately before the start of and during the last week of radiotherapy. RESULTS: At the beginning of intensity modulated radiation therapy, daily mean rectal doses were 74±8 cGy (mean±standard deviation) and 105±25 cGy (mean±standard deviation) with vs. without Hylaform, respectively (p=0.01). Expanded Prostate Cancer Index Composite Bowel Bother scores decreased by 0±3 (mean±standard deviation) and 11±14 (mean±standard deviation) in patients who did and did not receive Hylaform, respectively (p=0.03). CONCLUSIONS: Hylaform increased the separation between the prostate and rectum and decreased the mean rectal dose, thereby improving the gastrointestinal-related acute QOL of prostate cancer patients undergoing radiotherapy. Patients will be followed up long term to determine if the improvement in acute QOL also translates into an improvement in late QOL.

A prospective study of intrafraction prostate motion in the prone vs. supine position.

PURPOSE: To prospectively analyze prostate intrafraction motion in the prone vs. supine position and to assess patient satisfaction with these two positions. METHODS AND MATERIALS: Fifteen prostate cancer patients underwent implantation of five fiducial gold seeds in their prostate for localization. Patients were treated with high-dose-rate brachytherapy to 2,200 cGy followed by intensity-modulated radiation therapy (IMRT) to 5,040 cGy. Patients underwent computed tomography simulation and IMRT in the prone position. For the first five IMRT treatments, an electronic portal imaging system was used to acquire anteroposterior (AP) and lateral images pretreatment and posttreatment. We then repositioned each patient supine and repeated the process, resulting in 600 images. RESULTS: Mean +/- standard deviation intrafraction prostate motion was 2.1 +/- 1.2 mm and 1.7 +/- 1.4 mm (AP, p = 0.47), 2.2 +/- 2.0 mm and 1.6 +/- 1.8 mm (superoinferior, p = 0.16), and 1.0 +/- 1.2 mm and 0.6 +/- 0.9 mm (left-right, p = 0.03) in the prone and supine positions, respectively. Eighty percent of patients stated that they were more comfortable in the supine position (p = 0.02). CONCLUSIONS: Prone and supine positions resulted in a similar magnitude of AP and superoinferior intrafraction prostate motion (2 mm). Because there was no significant difference in the magnitude of AP and superoinferior prostate motion prone vs. supine and patients were more comfortable in the supine position, patients now undergo IMRT to the prostate and seminal vesicles at our center in the supine position.

Results with accelerated partial breast irradiation in terms of estrogen receptor, progesterone receptor, and human growth factor receptor 2 status.

PURPOSE: To report our results with accelerated partial breast irradiation (APBI) in terms of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER-2/neu) status. METHODS AND MATERIALS: Between February 2003 and June 2009, 209 women with early-stage breast carcinomas were treated with APBI using multicatheter, MammoSite, or Contura brachytherapy to 34 Gy in 10 fractions twice daily over 5-7 days. Three patient groups were defined by receptor status: Group 1: ER or PR (+) and HER-2/neu (-) (n = 180), Group 2: ER and PR (-) and HER-2/neu (+) (n = 10), and Group 3: ER, PR, and HER-2/neu (-) (triple negative breast cancer, n = 19). Median follow-up was 22 months. RESULTS: Group 3 patients had significantly higher Scarff-Bloom-Richardson scores (p < 0.001). The 3-year ipsilateral breast tumor control rates for Groups 1, 2, and 3 were 99%, 100%, and 100%, respectively (p = 0.15). Group 3 patients tended to experience relapse in distant sites earlier than did non-Group 3 patients. The 3-year relapse-free survival rates for Groups 1, 2, and 3 were 100%, 100%, and 81%, respectively (p = 0.046). The 3-year cause-specific and overall survival rates for Groups 1, 2, and 3 were 100%, 100%, and 89%, respectively (p = 0.002). CONCLUSIONS: Triple negative breast cancer patients typically have high-grade tumors with significantly worse relapse-free, cause-specific, and overall survival. Longer follow-up will help to determine whether these patients also have a higher risk of ipsilateral breast tumor relapse.

Preliminary results with accelerated partial breast irradiation in high-risk breast cancer patients.

PURPOSE: To analyze prognostic factors in adequately staged breast cancer patients who were treated with accelerated partial breast irradiation (APBI). METHODS AND MATERIALS: Axillary staging was required for invasive carcinomas. Between February 2003 and June 2009, 204 women with early stage breast carcinomas were treated with APBI using multicatheter, MammoSite, or Contura brachytherapy to 34 Gy in 10 fractions 2 times per day. Six patient characteristics were examined for prognostic significance: (1) N stage, (2) estrogen receptor (ER) status, (3) histologic subtype, (4) margin status, (5) age, and (6) tumor size. The median followup was 22 months. RESULTS: There were three failures in the ipsilateral breast (all were elsewhere failures), one relapse in the axilla, and seven relapses at any site. The presence of positive axillary node(s) had a significant adverse effect on ipsilateral breast tumor control (p=0.045) and locoregional control (p=0.001). The presence of an ER (-) tumor had a significant adverse effect on relapse-free survival (p=0.04). CONCLUSIONS: The patients with positive axillary node(s) were at increased risk for failure elsewhere in the ipsilateral breast or axilla, and the patients with ER (-) tumors were at increased risk for relapse at any site. However, it is unclear whether the pN1 and ER (-) patients would have faired any better if they had received whole breast irradiation rather than APBI. We believe that the patients with positive axillary node(s) or ER (-) tumors should be treated on clinical trials to better define the role of APBI.

Cross-linked hyaluronan gel reduces the acute rectal toxicity of radiotherapy for prostate cancer.

PURPOSE: To prospectively analyze whether cross-linked hyaluronan gel reduces the mean rectal dose and acute rectal toxicity of radiotherapy for prostate cancer. METHODS AND MATERIALS: Between September 2008 and March 2009, we transperitoneally injected 9 mL of cross-linked hyaluronan gel (Hylaform; Genzyme Corporation, Cambridge, MA) into the anterior perirectal fat of 10 early-stage prostate cancer patients to increase the separation between the prostate and rectum by 8 to 18 mm at the start of radiotherapy. Patients then underwent high-dose rate brachytherapy to 2,200 cGy followed by intensity-modulated radiation therapy to 5,040 cGy. We assessed acute rectal toxicity using the National Cancer Institute Common Terminology Criteria for Adverse Events v3.0 grading scheme. RESULTS: Median follow-up was 3 months. The anteroposterior dimensions of Hylaform at the start and end of radiotherapy were 13 +/- 3mm (mean +/- SD) and 10 +/- 4mm, respectively. At the start of intensity-modulated radiation therapy, daily mean rectal doses were 73 +/- 13 cGy with Hylaform vs. 106 +/- 20 cGy without Hylaform (p = 0.005). There was a 0% incidence of National Cancer Institute Common Terminology Criteria for Adverse Events v3.0 Grade 1, 2, or 3 acute diarrhea in 10 patients who received Hylaform vs. a 29.7% incidence (n = 71) in 239 historical controls who did not receive Hylaform (p = 0.04). CONCLUSIONS: By increasing the separation between the prostate and rectum, Hylaform decreased the mean rectal dose. This led to a significant reduction in the acute rectal toxicity of radiotherapy for prostate cancer.

Preliminary results in prostate cancer patients treated with high-dose-rate brachytherapy and intensity modulated radiation therapy (IMRT) vs. IMRT alone.

PURPOSE: To analyze results with high-dose-rate (HDR) brachytherapy and intensity modulated radiation therapy (IMRT) vs. IMRT alone for prostate cancer. METHODS AND MATERIALS: Between October 2003 and August 2008, 284 patients with early stage prostate cancer underwent HDR brachytherapy to 2200cGy and IMRT to 5040cGy (n=240) or IMRT alone to 7920-8100cGy (n=44). RESULTS: The median followup was 2.2 years. There was no significant difference in terms of the proportions of patients who had diabetes mellitus (p=0.07) or who received hormonal therapy (p=0.75) by radiotherapy technique. The 3-year biochemical disease-free survival rates in low-risk, intermediate-risk, and high-risk patients treated with HDR brachytherapy and IMRT are 100%, 98%, and 93%, respectively. The 3-year biochemical disease-free survival rates in low-risk, intermediate-risk, and high-risk patients treated with IMRT alone are 100%, 100%, and 67%, respectively. There was no significant difference in biochemical disease-free survival or toxicity between treatment groups. The similarity in outcomes between treatment groups remained unchanged when we examined only hormone-naive patients. CONCLUSIONS: The HDR brachytherapy and IMRT yielded similar biochemical disease-free survival and toxicity to IMRT alone. As a result, we continue to base treatment on physician and patient preference. Longer followup will help to determine the role of HDR brachytherapy and IMRT in the treatment of early stage prostate cancer, particularly because a number of patients received androgen deprivation therapy and we delivered a higher biologically effective dose with combined modality therapy.