Varagur Venkatesan

A Phase II Trial of Arc-Based Hypofractionated Intensity-Modulated Radiotherapy in Localized Prostate Cancer

PURPOSE To evaluate acute and late genitourinary (GU) and gastrointestinal (GI) toxicity and biochemical control of hypofractionated, image-guided (fiducial markers or ultrasound guidance), simplified intensity-modulated arc therapy for localized prostate cancer. METHODS AND MATERIALS This Phase II prospective clinical trial for T1a-2cNXM0 prostate cancer enrolled 66 patients who received 63.2 Gy in 20 fractions over 4 weeks. Fiducial markers were used for image guidance in 30 patients and daily ultrasound for the remainder. Toxicity was scored according to the National Cancer Institute Common Terminology Criteria for Adverse Events version 3.0. RESULTS Median follow-up was 36 months. Acute Phase Grade 2 and 3 toxicity was 34% and 9% for GU vs. 25% and 10% for GI symptoms. One Grade 4 acute GI toxicity occurred in a patient with unrecognized Crohns disease. Late Grade 2 and 3 toxicity for GU was 14% and 5%, and GI toxicity was 25% and 3%. One late GI Grade 4 toxicity was observed in a patient with significant comorbidities (anticoagulation, vascular disease). Acute GI toxicity ≥ Grade 2 was shown to be a predictor for late toxicity Grade ≥ 2 (p < 0.001). The biochemical disease-free survival at 3 years was 95%. CONCLUSIONS Hypofractionated simplified intensity-modulated arc therapy radiotherapy given as 63.2 Gy in 20 fractions demonstrated promising biochemical control rates; however, higher rates of acute Grade 3 GU and GI toxicity and higher late Grade 2 GU and GI toxicity were noted. Ongoing randomized controlled trials should ultimately clarify issues regarding patient selection and the true rate of severe toxicity that can be directly attributed to hypofractionated radiotherapy.

Epithelioid leiomyosarcoma of the larynx

Tumors of smooth muscle origin are rare in the upper aerodigestive tract, due to the paucity of smooth muscle in the area. A review of the literature revealed 34 reported cases of leiomyoma, 9 cases of leiomyosarcoma, and only 2 cases of epithelioid leiomyoma arising in the larynx.

Can radiological changes in lymph node volume during treatment predict success of radiation therapy in patients with locally advanced head and neck squamous cell carcinoma

Assessment of nodal response after radiotherapy (RT) for head and neck squamous cell carcinoma is difficult, as both CT and positron emission tomography scanning have limited predictive value for residual disease. We sought to measure changes in nodal volume during RT to determine whether such changes are predictive of nodal disease control.

Evaluation of tomotherapy MVCT image enhancement program for tumor volume delineation

The aims of this study were to investigate the variability between physicians in delineation of head and neck tumors on original tomotherapy megavoltage CT (MVCT) studies and corresponding software enhanced MVCT images, and to establish an optimal approach for evaluation of image improvement. Five physicians contoured the gross tumor volume (GTV) for three head and neck cancer patients on 34 original and enhanced MVCT studies. Variation between original and enhanced MVCT studies was quantified by DICE coefficient and the coefficient of variance. Based on volume of agreement between physicians, higher correlation in terms of average DICE coefficients was observed in GTV delineation for enhanced MVCT for patients 1, 2, and 3 by 15%, 3%, and 7%, respectively, while delineation variance among physicians was reduced using enhanced MVCT for 12 of 17 weekly image studies. Enhanced MVCT provides advantages in reduction of variance among physicians in delineation of the GTV. Agreement on contouring by the same physician on both original and enhanced MVCT was equally high. PACS numbers: 87.57.N‐, 87.57.np, 87.57.nt

Impact of urethrography on geometric uncertainty in prostate cancer radiotherapy

Results: The average systematic displacement (and standard deviation) of the prostate on treatment as measured from the position at the time of simulation/urethrography was 0.02cm (0.24), 0.00cm (0.39), and 0.32cm (0.38) in the x (left:, right:), y(anterior:, posterior:) and z(cephalad:, caudad:) directions, respectively (Figure). The average threedimensional vector of 0.32cm was in an anterior-cephalad direction; consistent with the urethrography induced prostate motion noted by Malone (1). Using our measurements and the Monte Carlo geometric error equations from van Herk (2), a required planning target margin (PTV) of 0.87cm was needed in order to give 90% of patients an equivalent uniform dose (EUD) of at least 98% of the prescription dose. For coverage of the prostate for 95% of the treatment fractions, PTV margins of 1.0cm and 0.6cm were necessary with and without the inclusion of the systematic error attributed to the urethrogram. Conclusions: Using a combination of implanted markers and weekly CT scans we detected a systematic shift of the prostate apex and centre of mass superiorly/cephalad at the time of simulation/urethrography compared to during treatment. While our current 1cm PTV margins are sufficient to compensate for geometric uncertainties including this shift, reduced margins in the context of dose or fraction escalation may require methods other than urethrography to help localize the apex of the prostate.

Response to “Adenocarcinoma not otherwise specified or cribriform adenocarcinoma on dorsum of tongue?”

The Editor Current Oncology May 21, 2013 We thank the writers of the letter to the editor titled “Adenocarcinoma not otherwise specified or cribriform adenocarcinoma on dorsum of tongue?” for their interest in our paper “Adenocarcinoma not otherwise specified on dorsum of tongue: case report and literature review”1. We appreciate the time and effort they took in providing their opinion on our paper, and we enjoyed their response and thoroughness. The letter provides a nice summary of cribriform adenocarcinoma of minor salivary gland (camsg) origin, a tumour originally described in 1999, but not fully studied until 2011 by Skalova et al.2. Our adenocarcinoma nos [not otherwise s pecified] certainly had some features that suggest a diagnosis of camsg, including the low-power architecture of the tumour and the results of the immunohistochemical panel. However, its nuclei lacked the expected “ground glass” quality, instead resembling papillary carcinoma of the thyroid. I would draw the reader’s attention to the Case Description section. In that section, we mention that the patient presented to our institution in December 2005, when the material was examined. At that time, camsg was not fully recognized (it had been briefly mentioned in the latest issue of the World Health Organization classification). We therefore made a diagnosis of adenocarcinoma nos. When we were preparing the case for publication, we were aware of Dr. Skalova’s work on camsg. The main purpose of our paper was to discuss the management of our patient’s case and to review the literature on management of adenocarcinoma at a particular site. Therefore, we believed it was more important to publish the case using the diagnosis made at the time and on which treatment was based.