Clinical implementation of tangential field intensity modulated radiation therapy (IMRT) using sliding window technique and dosimetric comparison with 3D conformal therapy (3DCRT) in breast cancer.

The purpose of this study was to evaluate the clinical implementation of tangential field IMRT using sliding window technique and to compare dosimetric parameters with 3-dimensional conformal radiation therapy (3DCRT). Twenty breast cancer patients were randomly selected for comparison of intensity modulated radiation therapy (IMRT)-based treatment plan with 3DCRT. Inverse treatment was performed using the sliding window technique, employing the Eclipse Planning System (version 7.1.59, Varian, Palo Alto, CA). The dosimetric parameters compared were V(95) (the percentage of target volume getting > or =95% of prescribed dose), V(105), V(110), and dose homogeneity index, DHI (percentage of target volume getting between 95% and 110% of prescribed dose). The mean V(95), DHI, V(105), and V(110) for target volume for IMRT vs. 3D were 90.6% (standard deviation [SD]: 3.2) vs. 91% (SD: 3.0), 87.7 (SD: 6.0) vs. 82.6 (SD: 7.8), 27.3% (SD: 20.3) vs. 49.4% (SD: 14.3), and 2.8 (SD: 5.6) vs. 8.4% (SD: 7.4), respectively. DHI was increased by 6.3% with IMRT compared to 3DCRT (p < 0.05). The reductions of V(105) and V(110) for the IMRT compared to 3DCRT were 44.7% and 66.3%, respectively (p < 0.01). The mean dose and V(30) for heart with IMRT were 2.3 (SD: 1.1) and 1.05 (SD: 1.5) respectively, which was a reduction by 6.8% and 7.9%, respectively, in comparison with 3D. Similarly, the mean dose and V(20) for the ipsilateral lung and the percentage of volume of contralateral volume lung receiving > 5% of prescribed dose with IMRT were reduced by 9.9%, 2.2%, and 35%, respectively. The mean of total monitor units used for IMRT and 3DCRT was about the same (397 vs. 387). The tangential field IMRT for intact breast using sliding window technique was successfully implemented in the clinic. We have now treated more than 1000 breast cancer patients with this technique. The dosimetric data suggest improved dose homogeneity in the breast and reduction in the dose to lung and heart for IMRT treatments, which may be of clinical value in potentially contributing to improved cosmetic results and reduced late treatment-related toxicity.

Treatment techniques for 3D conformal radiation to breast and chest wall including the internal mammary chain.

Breast, chest wall, and regional nodal irradiation have been associated with an improved outcome in high-risk breast cancer patients. Complex treatment planning is often utilized to ensure complete coverage of the target volume while minimizing the dose to surrounding normal tissues. The 2 techniques evaluated in this report are the partially wide tangent fields (PWTFs) and the 4-field photon/electron combination (the modified "Kuske Technique"). These 2 techniques were evaluated in 10 consecutive breast cancer patients. All patients had computerized tomographic (CT) scans for 3D planning supine on a breast board. The breast was defined clinically by the physician and confirmed radiographically with radiopaque bebes. The resulting dose-volume histograms (DVHs) of normal and target tissues were then compared. The deep tangent field with blocks resulted in optimal coverage of the target and the upper internal mammary chain (IMC) while sparing of critical and nontarget tissues. The wide tangent technique required less treatment planning and delivery time. We compared the 2 techniques and their resultant DVHs and feasibility in a busy clinic.

Early clinical outcome with concurrent chemotherapy and extended-field, intensity-modulated radiotherapy for cervical cancer.

PURPOSE: To assess the early clinical outcomes with concurrent cisplatin and extended-field intensity-modulated radiotherapy (EF-IMRT) for carcinoma of the cervix. METHODS AND MATERIALS: Thirty-six patients with Stage IB2-IVA cervical cancer treated with EF-IMRT were evaluated. The pelvic lymph nodes were involved in 19 patients, and of these 19 patients, 10 also had para-aortic nodal disease. The treatment volume included the cervix, uterus, parametria, presacral space, upper vagina, and pelvic, common iliac, and para-aortic nodes to the superior border of L1. Patients were assessed for acute toxicities according to the National Cancer Institute Common Toxicity Criteria for Adverse Events, version 3.0. All late toxicities were scored with the Radiation Therapy Oncology Group late toxicity score. RESULTS: All patients completed the prescribed course of EF-IMRT. All but 2 patients received brachytherapy. Median length of treatment was 53 days. The median follow-up was 18 months. Acute Grade > or = 3 gastrointestinal, genitourinary, and myelotoxicity were seen in 1, 1, and 10 patients, respectively. Thirty-four patients had complete response to treatment. Of these 34 patients, 11 developed recurrences. The first site of recurrence was in-field in 2 patients (pelvis in 1, pelvis and para-aortic in 1) and distant in 9 patients. The 2-year actuarial locoregional control, disease-free survival, overall survival, and Grade > or = 3 toxicity rates for the entire cohort were 80%, 51%, 65%, and 10%, respectively. CONCLUSION: Extended-field IMRT with concurrent chemotherapy was tolerated well, with acceptable acute and early late toxicities. The locoregional control rate was good, with distant metastases being the predominant mode of failure. We are continuing to accrue a larger number of patients and longer follow-up data to further extend our initial observations with this approach.

Breast skin doses from brachytherapy using MammoSite HDR, intensity modulated radiation therapy, and tangential fields techniques.

Skin doses from brachytherapy using MammoSite HDR, Intensity Modulated Radiation Therapy (IMRT), and conventional tangential fields techniques were compared. For each treatment technique, skin doses were measured using paired thermoluminescent dosimeters placed on the patient's skin: (i) directly above the balloon catheter during MammoSite HDR brachytherapy treatments and (ii) 4 cm inside the treatment borders during the IMRT and conventional breast treatments. The mean dose measured was about 58% of the prescription dose for the patients treated using the MammoSite technique. On the other hand, for patients treated with IMRT and tangential fields, the mean dose was found to be about 69% and 71% of the corresponding prescription dose. This study suggests that in breast cancer radiation treatments the MammoSite HDR technique reduces skin doses compared to IMRT and tangential field techniques.

Feasibility of concurrent cisplatin and extended field radiation therapy (EFRT) using intensity-modulated radiotherapy (IMRT) for carcinoma of the cervix.

OBJECTIVES: To assess the acute tolerance of delivering concurrent cisplatin and extended field radiotherapy (EFRT) using intensity-modulated radiotherapy technique (IMRT) for cancer of the cervix. METHODS: All patients receiving definitive treatment for cervical cancer were treated with EFRT using IMRT technique and concurrent cisplatin. The treatment volume included the cervix, uterus, parametria, presacral space, upper vagina, pelvic, common iliac, and paraaortic nodes to the top of L1. All regions received 45 Gy (25 fractions) with a simultaneous boost to involved nodes (55 Gy/25 fractions). Patients were assessed weekly for toxicity and response. RESULTS: Twenty-two consecutive patients underwent treatment. All patients completed the prescribed course of EFRT. Median treatment length was 39.5 days (range 36-53). Treatment breaks of 2 and 3 days were required for bone marrow toxicity in 2 patients. The final week of chemotherapy was held in 2 patients because of neutropenia. No patient suffered acute or subacute grade 3 or 4 GI or GU toxicity. CONCLUSION: In this clinical study, an IMRT technique was used to successfully deliver EFRT with concurrent chemosensitization for cervical cancer. The technique was associated with an acceptable acute toxicity without significant treatment protraction. This new role for IMRT merits further evaluation with larger patient numbers and longer follow-up.

Preoperative chemoradiation for locally advanced carcinoma of the vulva.

OBJECTIVE: A twice daily (BID) radiation treatment schedule (interval of 4-6 h) delivered concurrent with chemotherapy for advanced or critically located carcinoma of the vulva was modeled on the schema developed by the Gynecology Oncology Group (GOG). Inguinal nodes were included in the treatment fields even if clinically negative. This review analyzed the outcomes using this approach. METHODS: A retrospective review was conducted of the records of 18 patients with vulvar cancer. Patients were treated with a modified GOG schema using 5-fluorouracil (5FU) and cisplatin with BID radiation treatments during the first and last weeks of treatment and seven daily radiation treatments in between. The regional nodes and primary tumor were prescribed 44.6 Gy. Resection of the primary tumor bed and inguinal dissection was planned at 4-6 weeks post-treatment. Clinical and pathological responses as well as locoregional control and toxicity were assessed. RESULTS: All patients responded. There were 13/18 complete clinical responses (cCR), of whom 12 remained NED at 25 months. Of the five partial clinical response (cPR) patients, two have suffered local recurrences, despite surgical resection in one and electron boost in the other. All patients developed a desquamative perineal skin reaction necessitating a mean treatment break of 15 days. No severe hematological toxicity was encountered, and only one patient had grade 3 small bowel toxicity. One patient required surgical debridement for groin wound breakdown. CONCLUSION: The use of BID chemoradiation resulted in complete or partial responses in all cases. Post-treatment groin dissection can be performed without significant post-operative complications.