Abstract P5-14-06: Outcomes in 500 patients from a large, retrospective study of APBI with a strut-based breast brachytherapy applicator

Purpose/Objectives:

The SAVI Collaborative Research Group (SCRG) is a coalition of 14 institutions who have retrospectively compiled a large database of APBI patients treated with a strut-based brachytherapy device (SAVI). This report details the findings of statistical correlations between numerous dosimetric variables and cosmetic outcome.

Materials/Methods:

The SCRG study enrolled 1005 patients. A subset of patients with complete dosimetry and more than 1 year of follow-up by a radiation oncologist were analyzed for toxicity, cosmesis and recurrence/survival. Dosimetric parameters were tabulated for patients, including: V90, V95, V100, V150, V200, skin spacing (skin-bridge), maximum skin dose, tumor size, PTV-Eval volume and applicator size (model). Toxicity (e.g., telangiectasia, fibrosis, fat necrosis, seroma) were graded by physicians for patients with at least 1 year of follow-up (up to 6 years) using the CTCAE v3 Scale and fat necrosis using a simplified CTCAE scale (Grade 1 asymptomatic but seen on imaging, grade 2 symptomatic without intervention, & grade 3 required intervention).

Results:

Median follow up in this cohort was 29.2 months (range 2.4 to 72.2 months). Follow up was >2 yr and >3 yr for 323 and 191 subjects, respectively. Overall, in 500 subjects the late toxicity (grade ≥2) rates were less than 5% during follow up: telangiectasia 1.0%, fibrosis 4.1%, seroma 2.9% and fat necrosis 0.6%. Cosmesis was reported at various post-APBI follow-up visits following treatment completion (6, 12, 24, 36, 48 & 60+ months). For the 6 and 12 month intervals, 98% (n = 122) and 97% (n = 262) were reported excellent or good (E/G), respectively. At 24, 36, 48 and 60 month intervals, the E/G rates were 93% (n = 184), 90% (n = 98), 100% (n = 41) and 94% (n = 15), respectively. The raw rates of ipsilateral breast tumor recurrence (IBTR) and TR/MM were 1.6% (n = 8) and 1.2% (n = 6), respectively, in 500 patients with >1 year of follow up. The 1- and 2-year actuarial rates of overall survival and disease-free survival were: 1-year, 99.6% & 99.4%, resp. and 2-year, 99.2% & 96.7%.

Conclusions:

APBI treatment with the strut-based applicators was well-tolerated, demonstrated low toxicity rates, favorable cosmetic outcomes and excellent local control over the follow-up to date. Patients with challenging breast anatomy were successfully treated with strut-based devices.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-14-06.

Control of acute toxicity with amifostine and pelvic chemoradiotherapy

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Background: Amifostine is an FDA approved normal tissue radioprotector for head and neck carcinoma. Several studies have also demonstrated a radioprotective role in pelvic malignancies. However, literature also shows that amifostine has substantial toxicity. We examined patient compliance with combined chemoradiotherapy and daily amifostine subcutaneous injections, the incidence of acute toxicity, and the efficacy of interventions. Methods: Patients undergoing pelvic radiotherapy and concurrent chemotherapy were eligible. Patients received daily subcutaneous injections of 500 mg amifostine 30 to 60 minutes before radiotherapy. Injection pain, erythema, and rash were recorded daily, as was patient blood pressure before and after receiving amifostine and radiotherapy. Treating physicians evaluated patients at least weekly. Symptoms were recorded and graded using the NCI Common Toxicity Criteria. The protocol was amended early in accrual to include nausea prophylaxis guidelines. Results: Nineteen patients have been entered into this study. Fourteen had cervix cancer, four had rectal cancer, and one had anal cancer. Four patients (21%) received <1 week of amifostine. Seven (37%) received <50% of their planned injections. Fifty three percent received >80% of their injections, while 32% received the full course of amifostine. Of those that prematurely discontinued amifostine, 1 withdrew before receiving any injections, 1 transferred to another facility, 6 withdrew because of nausea, 2 secondary to rash, 2 secondary to injection pain. One developed paresthesias. Of those that withdrew because of nausea, all but one received >50% of the planned injections. Twenty six percent experienced grade 3 nausea. When comparing patients that did not receive nausea prophylaxis with those that did, grade two or three nausea dropped from 100% to 29%. No patients developed grade 3 rash. Two patients experienced hypotension. Nine patients (47%) complained of injection site pain. Conclusions: Subcutaneous amifostine is reasonably well tolerated when used with pelvic radiotherapy. Nausea was a significant side effect seen in this study. Assuring adequate hydration and use of prophylactic antiemetic medication significantly decreased nausea.

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An incremental dosing protocol for women with severe vaginal trichomoniasis and adverse reaction to metronidazole

OBJECTIVE

Our purpose was to develop and test an incremental dosing protocol for women with adverse reaction to metronidazole and severe symptomatic Trichomonas vaginitis.

STUDY DESIGN

Two women with documented Trichomonas infection and presumed metronidazole allergy were initially treated with a number of alternative methods without success. With persistent severe symptoms associated with their infection, these women were admitted to the hospital and underwent an intravenous incremental metronidazole dosing protocol.

RESULTS

Both patients were successfully treated without adverse event. They are both symptom-free and apparently cured several months after treatment.

CONCLUSION

This protocol offers a new therapeutic option to women with adverse metronidazole reactions and severe symptomatic Trichomonas vaginitis resistant to treatment with nonmetronidazole therapy.