Tarita O. Thomas

Outcome of patients treated with a single-fraction dose of palliative radiation for cutaneous T-cell lymphoma.

PURPOSE Cutaneous T-cell lymphoma (CTCL) is a radiosensitive tumor. Presently, treatment with radiation is given in multiple fractions. The current literature lacks data that support single-fraction treatment for CTCL. This retrospective review assesses the clinical response in patients treated with a single fraction of radiation. METHODS AND MATERIALS This study reviewed the records of 58 patients with CTCL, primarily mycosis fungoides, treated with a single fraction of palliative radiation therapy (RT) between October 1991 and January 2011. Patient and tumor characteristics were reviewed. Response rates were compared using Fishers exact test and multiple logistic regressions. Survival rates were determined using the Kaplan-Meier method. Cost-effectiveness analysis was performed to assess the cost of a single vs a multifractionated treatment regimen. RESULTS Two hundred seventy individual lesions were treated, with the majority (97%) treated with ≥ 700 cGy; mean follow-up was 41.3 months (range, 3-180 months). Response rate by lesion was assessed, with a complete response (CR) in 255 (94.4%) lesions, a partial response in 10 (3.7%) lesions, a partial response converted to a CR after a second treatment in 4 (1.5%) lesions, and no response in 1 (0.4%) lesion. The CR in lower extremity lesions was lower than in other sites (P=.0016). Lesions treated with photons had lower CR than those treated with electrons (P=.017). Patients with lesions exhibiting large cell transformation and tumor morphology had lower CR (P=.04 and P=.035, respectively). Immunophenotype did not impact response rate (P=.23). Overall survival was significantly lower for patients with Sézary syndrome (P=.0003) and erythroderma (P<.0001). The cost of multifractionated radiation was >200% higher than that for single-fraction radiation. CONCLUSIONS A single fraction of 700 cGy-800 cGy provides excellent palliation for CTCL lesions and is cost effective and convenient for the patient.

The tolerance of gastrointestinal organs to stereotactic body radiation therapy: what do we know so far?

As stereotactic body radiation therapy (SBRT) for gastrointestinal (GI) gains popularity, there is a need to optimize doses and fractionation to minimize GI toxicity. GI organs that have classically developed radiation-induced toxicity include the liver & biliary system, small bowel, esophagus, and rectum. While the literature quantifies dose restrictions for these organs under standard fractionation, there is limited data regarding toxicity with the ablative dose schedules used in SBRT. We conducted a review of the literature to identify prospective and retrospective studies that detail GI toxicities when SBRT was employed. Based on the literature, the median SBRT dose for abdominal and thoracic tumors ranged from 24 to 60 Gy, at 5 to 25 Gy per fraction. The respective observed frequencies of grade 3 and 4 toxicities for the liver, biliary system, small bowel, and esophagus were variable among different studies. Typically, patients who suffered grade 3 and 4 toxicities were more likely to have had some form of systemic therapy as well. The effect of dose, fractionation, timing, and volume on GI toxicities has been described in the literature but more data is necessary to develop uniform treatment guidelines for SBRT.

Commentary on "Accelerated partial breast irradiation consensus statement: Update of an ASTRO Evidence-Based Consensus Statement"

5 Although the new American Society for Radiation Oncology (ASTRO) consensus statement on accelerated partial breast irradiation (APBI) reflects many important changes relative to case selection and inclusion criteria for APBI, we would like to address our concerns specifically regarding the recommendations on the use of low-energy x-ray intraoperative radiation therapy (IORT). The consensus should include a statement that targeted intraoperative radiation therapy (TARGIT) IORT achieves local control similar to external beam radiation therapy (EBRT) with a potential for a survival benefit.1-4 Although the panel correctly recognized that the local recurrence rate in prepathology (TARGIT given simultaneously during lumpectomy) stratum was NOT significantly different from the whole-breast external beam irradiation (WBI) arm (2.1% vs 1.1%, P = .31), the panel gave “greater weight” to the local recurrence rate of the entire IORT cohort (prepathology and postpathology [TARGIT given after lumpectomy as a second procedure by reopening the wound at a median of 37 days after the initial excision] strata combined). Sometimes the devil is in the details. The TARGIT-A trial specified stratification between preand postpathology before randomization to

Single-Fraction Radiotherapy for CD30(+) Lymphoproliferative Disorders.

Objectives. CD30+ lymphoproliferative disorder is a rare variant of cutaneous T-cell lymphoma. Sustained complete response following first-line treatments is rare. This retrospective review evaluates the response of refractory or recurrent lesions to palliative radiation therapy. Methods. The records of 6 patients with 12 lesions, treated with radiation therapy, were reviewed. All patients received previous first-line treatments. Patients with clinical and pathological evidence of symptomatic CD30+ lymphoproliferative disorder, with no history of other cutaneous T-cell lymphoma variants, and with no prior radiation therapy to the index site were included. Results. The median age of patients was 50.5 years (range, 15–83 years). Median size of the treated lesions was 2.5 cm (range, 2–7 cm). Four sites were treated with a single fraction of 750–800 cGy (n = 3) and 8 sites were treated with 4000–4500 cGy in 200–250 cGy fractions (n = 3). Radiation therapy was administered with electrons and bolus. Median follow-up was 113 months (range, 16–147 months). For all sites, there was 100% complete response with acute grade 1-2 dermatitis. Conclusions. For recurrent and symptomatic radiation-naïve CD30+ lymphoproliferative disorder lesions, palliative radiation therapy shows excellent response. A single fraction of 750–800 cGy is as effective as a multifractionated course and more convenient.

Whole-Field Sequential Intensity-Modulated Radiotherapy for Local-Regional Advanced Head-and-Neck Squamous Cell Carcinoma.

Purpose:There is little published data on the technique and results of whole-field (WF) sequential intensity–modulated radiotherapy (S-IMRT) for patients with head-and-neck squamous cell carcinoma (HNSCC). We report the treatment outcomes, adverse events (AEs), and dosimetric parameters in local-regional advanced (LRA) HNSCC patients treated with the WF S-IMRT technique. Methods:The IRB approved this retrospective study. Patients received WF S-IMRT with or without concomitant chemotherapy. Three separate IMRT plans corresponding to 3 planning target volumes were generated. This study reports patient and tumor characteristics, treatment-induced acute AEs based on CTCAE version 3.0, chronic AEs according to RTOG scale and treatment outcomes, local-regional control (LRC), distant metastases (DM), relapse-free survival (RFS), and overall survival (OS). Results:Between January 2003 and December 2010, 103 patients with LRA HNSCC were treated either definitively or postoperatively with WF S-IMRT, with (99 patients) or without (4 patients) concurrent chemotherapy. The median age was 55 years (range, 30 to 89 y). The median cumulative target dose was 70 Gy (range, 60 to 75 Gy). At a median follow-up of 40 months (range, 4 to 95 mo), the 2- and 5-year rates of OS were 94% and 77%, RFS were 90% and 84%, LRC were 97% and 93%, and DM were 9% and 11%, respectively. Grade 3 acute AEs included mucositis (68%), dysphagia (35%), weight loss (19.6%), and xerostomia (7.8%). Chronic worst grade 3 AEs included xerostomia (21.9%), weight loss (12.8%), and dysphagia (12.5%). Chronic grade 3 AEs at last follow-up included weight loss (6.25%), dysphagia (6.2%), and xerostomia (6.2%). No patient had an acute or chronic grade 4 AE, brachial plexopathy, or spinal cord injury. Conclusions:WF S-IMRT results in excellent tumor control and an acceptable toxicity profile in LRA HNSCC patients treated with this technique.

Dissecting receptor-G protein specificity using G alpha chimeras.

In conclusion, by taking advantage of the overall sequence homology and structural similarity of G alpha subunits, functional chimeric G alpha subunits can be generated and used as tools for the identification of sequence-specific factors that mediate receptor: G protein specificity. The [35S]GTP gamma S binding assay and the affinity shift activity assay are two sensitive biochemical approaches that can be used to assess receptor: G protein coupling in vitro. These in vitro assays limit confounding influences from cellular proteins and allow for the strict control of receptor: G protein ratios.

Intraoperative Radiation “Boost” to the Surgical Resection Bed following Pancreaticoduodenectomy for a Borderline Resectable Pancreatic Carcinoma: A Case Report

Neoadjuvant therapy including chemotherapy alone or concurrent chemotherapy with external bream radiation is a standard treatment strategy for borderline resectable pancreatic adenocarcinoma and is also used routinely for primary operable cancers at some institutions (1). The use of intraoperative radiation therapy (IORT) has been limited largely because of the logistical issues in delivery of radiation during surgery (2). This is the first reported case of a borderline resectable pancreas cancer patient who underwent neoadjuvant chemo-radiation therapy followed by resection with the use of IORT using the mobile IntraBeam device to boost the resection bed and improve local control by dose escalation.

Monte Carlo (MC)-based volumetric modulated arc therapy (VMAT) in locally advanced esophageal cancer with potential for dose escalation.

77 Background: Previous attempts at dose escalation in esophagus radiotherapy (RT), mostly based on older planning techniques, have not shown improved outcomes. We aimed to investigate the importance of newer, sophisticated dose algorithms and treatment techniques in escalating target dose and reducing dose to organs at risk (OAR). Methods: Treatment plans for 10 patients were retrospectively evaluated using 3D conformal radiotherapy (3DCRT), MC based intensity modulated radiotherapy (IMRT), and VMAT. Prescription dose was 45 Gy to the planning target volume (PTV) in 25 fractions followed by a 5.4 Gy boost in 3 fractions. PTV (mean±s.d. = 681±236 cc) were planned with BrainLab iPlan 4.1 software as IMRT and VMAT. Dose distributions were calculated with both pencil beam (PB) and MC algorithms. Each PTV was normalized to receive at least 95% of 50.4 Gy or 60 Gy dose. OARs were evaluated as per RTOG1010 dose guidelines. Paired t-tests were used for statistical analysis. Results: IMRT vs. 3DCRT PTV 50.4 Gy: I...