To inform intensity modulated radiation therapy delivery and future trials in anal squamous cell Purpose: Our purpose was to describe the patterns and predictors of treatment failure in patients receiving definitive chemoradiation therapy (CRT) for anal squamous cell carcinoma (ASCC), delivered using intensity modulated radiation therapy (IMRT). Methods and Materials: Our study was a retrospective cohort analysis of consecutive patients treated with curative intent for ASCC using CRT delivered with a standardized IMRT technique in 5 UK cancer centers. Patients were included from the start

Aims: Doseeresponse curves suggest that higher doses of radiotherapy improve the complete response rate in rectal cancer. The UK adopted the EXPERT trial dose and fractionation, 45 Gy in 25 fractions to the pelvis with a sequential 9 Gy in five fractions to the gross tumour, in patients where the aim was to maximise the complete response. In the Oxford University Hospital NHS Foundation Trust (Oxford, UK) we deliver a biological equivalent dose (BED5) in selected patients using intensity-modulated radiotherapy (IMRT) with a simultaneous integrated boost (SIB) in 25 fractions. We carried out a retrospective analysis of our series to: (i) document the toxicity of this protocol; (ii) ascertain whether dose constraints from RTOG 0822 were appropriate; (iii) assess the response. Materials and methods: The demographics and treatment details for all consecutive patients treated with this protocol were collected using electronic systems. Patients received 45 Gy to the elective nodes and 52 Gy using a SIB to the gross tumour with capecitabine chemotherapy using IMRT or RapidArc plans. Acute toxicity was collected prospectively during weekly reviews. For the purpose of this study, a dedicated gastrointestinal radiologist reviewed all baseline and posttreatment magnetic resonance images and assigned a magnetic resonance tumour regression grade (mrTRG). Results: Seventy-one patients were identified. Seventy completed radiotherapy with a median overall treatment time of 34 days (range 32e36 days); 67.6% received full-dose chemotherapy, with 21.2% receiving a reduced dose. There was a 4.2% incidence of grade 3þ non-haematological toxicity and 1.5% grade 3 þ haematological toxicity. 4.2% were admitted during their radiotherapy, with one death due to a pelvic abscess. The RTOG 0822 constraints were achieved in !75% of cases, other than the high-dose bladder constraint. mrTRG 1e2 was seen in 47.8%, with mrTRG 1 seen in 23.9%. Conclusions: We suggest that our protocol shows acceptable acute toxicity, with promising mrTRG results, and could be adopted by centres as an IMRT equivalent dose for EXPERT dose and fractionation.

The vagus nerve, as a result of its protracted course from the brain stem to the abdomen, can present a difficult imaging problem when it is compromised by a clinically occult lesion. The clinical and radiologic records of 48 patients with suspected vagus nerve dysfunction were reviewed to derive an efficient and effective approach to imaging this patient population. An imaging algorithm is proposed in which vagal neuropathies are divided both clinically and radiologically into proximal and distal categories. Proximal vagal lesions are part of a cranial neuropathy complex and have associated oropharyngeal signs and symptoms (e.g., abnormal gag reflex, uvular deviation). Distal vagal lesions occur as an isolated paralysis of the vagus nerve with no symptoms or signs referable to the oropharynx. Either computed tomography (CT) or magnetic resonance imaging can be used to diagnose proximal or distal lesions. However, CT will be insensitive in the detection of the more cephalic proximal lesions, especially those in the brain stem, basal cisterns, and skull base.

Aim There is significant international variation in the use of neoadjuvant radiation prior to total mesorectal excision. The MERCURY group advocate selective neoadjuvant chemoradiotherapy (CRT). We have performed a retrospective, single‐centre study of patients treated with CRT, where only the circumferential resection margin is threatened, with the aim of identifying whether a more selective approach to CRT provides acceptable local relapse rates (LRRs). Method All consecutive patients who underwent radical surgery for rectal adenocarcinoma over a 5‐year period (2007–2012) in the Oxford University Trust were considered. Electronic hospital systems were reviewed to obtain patient and tumour demographics, treatment and follow‐up information. All patients were classified into risk categories according to National Institute for Health and Care Excellence guidance. Data were analysed using Microsoft Excel and R. Results Two hundred and seventy‐two patients were identified: 123, 89 and 60 in the high‐, intermediate‐ and low‐risk categories, respectively. Seventy‐nine per cent of those in the high‐risk group, 6% in the intermediate and 5% in the low‐risk group underwent CRT. The overall 5‐year LRR and distant recurrence rate (DRR) were 5.2% and 17.8%, respectively. The 5‐year LRR for those who went straight to surgery was 2.0% and for those who had neoadjuvant CRT it was 7.4%. The DRR for these two groups was 8.5% and 18.9%, respectively. Conclusion Our series demonstrates that the use of CRT only in margin‐threatening tumours, results in an exceptionally low LRR for those without margin‐threatening disease. In routine clinical care, this strategy can minimize the significant morbidity of multimodal treatment and allow earlier introduction of systemic therapy to minimize distant recurrence.

Background and purpose: To determine if suppression of active bone marrow, as defined on FDG PETCT, is seen in on-treatment imaging of anal cancer patients receiving concurrent chemoradiation. Methods and materials: Scans from 26 patients participating in the ART trial (full title: Anal squamous cell carcinoma: Investigation of functional imaging during chemoRadioTherapy), a single center observational study with FDG PETCT prior to radiotherapy and at fraction 8-10 of concurrent chemoradiation were analysed. Active bone marrow was contoured in both the pelvis and un-irradiated thoracic spine. SUV and volume of active bone marrow after 8-10 fractions of treatment were compared to baseline. Dose metrics to pelvic active bone marrow were extracted and compared to reduction in SUV/active bone marrow volume and to blood count nadir using linear regression. Results: Suppression of active bone marrow is seen in the pelvis by a reduction in mean SUV and volume of active bone marrow after 8-10 fractions of treatment. Suppression is not seen in un-irradiated thoracic spine. Dose metrics were associated with reduced SUV and reduced volume of active bone marrow. Volume of active bone marrow receiving <20 Gy was associated with WCC/ANC nadir. 20 Gy was identified as the most likely clinically meaningful dose threshold for toxicity. Volume of active bone marrow receiving <20 Gy correlated to WCC and ANC with an increase of 100 cc being associated with an increase of 0.4 and 0.3 respectively. Conclusion: The effect of concurrent chemoradiation in suppression of active bone marrow is seen in ontreatment FDG PETCT scans. Chemotherapy appears well tolerated after 2 weeks of treatment.