Virtual Library

Start Your Search

N. Mohammed



Author of

  • +

    MO23 - Radiotherapy II: Lung Toxicity, Target Definition and Quality Assurance (ID 107)

    • Event: WCLC 2013
    • Type: Mini Oral Abstract Session
    • Track: Radiation Oncology + Radiotherapy
    • Presentations: 2
    • +

      MO23.04 - Is pre-trial quality assurance (QA) effective? A comparison of pre-trial QA versus ongoing QA for the CONVERT Trial. (ID 1809)

      10:30 - 12:00  |  Author(s): N. Mohammed

      • Abstract
      • Presentation
      • Slides

      Background
      CONVERT is an international randomised phase III trial comparing 45Gy in 30 fractions twice-daily and 66Gy in 33 fractions once-daily (given concurrently with cisplatin/etoposide) for good performance status patients with limited stage small cell lung cancer. A QA programme was set-up to standardise radiotherapy (RT) delivery across all centres.

      Methods
      The pre-trial QA exercise (PQE) involved completion of a questionnaire and treatment planning exercise. Each participating clinician was asked to select a previously treated patient, who fitted the entry criteria for the trial, and provide disease and organs at risk (OAR) outlines and a treatment plan for both arms of the trial. QA guidelines, including an atlas for OAR outlining, were distributed to participating centres. Additionally, at least one RT plan per centre was randomly collected during the trial (ongoing QA exercise-OQE). A comparison was made between the PQE and OQE for each centre, including a review of eligibility criteria, OAR and gross tumour volume (GTV) outlining, expansion to clinical target volume (CTV) and planning target volume (PTV).

      Results
      Twenty nine clinicians from 28 centres who had completed both the pre-trial QA and the ongoing QA were included in the analysis. From the pre-trial questionnaire it was reported that 3 centres were using beam energies of 10MV or more which was not permitted as per protocol. Subsequently the PQE showed that these all used acceptable beam energies. Four clinicians submitted ineligible patients for the PQE and none for the OQE. Twenty five clinicians (86.2%) used the correct GTV to CTV and CTV to PTV expansions for the PQE and OQE. Table 1 shows a comparison of adherence to protocol regarding OAR outlining between the PQE and OQE. Table 1

      Oesophagus outline Spinal canal outline Heart outline Lung-PTV outline
      PQE-OAR outline as per protocol (n=29) 19 (65.5%) 14 (48.3%) 4 (13.8%) 20 (68.9%)
      OQE-OAR outline as per protocol (n=29) 21 (72.4%) 18 (62.1%) 8 (27.6%) 20 (68.9%)
      Organ at risk doses were found to be within the tolerances specified in the trial protocol for both PQE and OQE.

      Conclusion
      A PQE improves clinicians’ compliance to trial protocol, and has been found in the OQE to reduce deviations across the participating centres that may confound the results of the study. Despite the fact that consistency of OAR outlining remained an issue in both the PQE and the OQE an overall improvement was seen following the PQE.

      Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.

    • +

      MO23.05 - Changes in lung radiotherapy techniques during the CONVERT Trial. A survey of participating centres. (ID 1820)

      10:30 - 12:00  |  Author(s): N. Mohammed

      • Abstract
      • Presentation
      • Slides

      Background
      CONVERT is an international randomised phase III trial, comparing 45Gy in 30 fractions twice-daily or 66Gy in 33 fractions once-daily (given concurrently with cisplatin/etoposide) for good performance status patients with limited stage small cell lung cancer. A survey was sent out to 69 clinicians who had randomised patients into the trial with the aim of establishing how radiotherapy techniques for lung cancer have changed over the 5 years since the trial opened.

      Methods
      As part of the pre-trial quality assurance process each centre was asked to complete a facility questionnaire giving details of treatment planning, delivery and verification techniques. Recruitment to the trial began in April 2008 and in January 2013, a further facility questionnaire was sent to centres. The survey was completed using an on-line survey tool.

      Results
      This analysis includes answers from the 34 clinicians who responded to the questionnaire. Changes in treatment planning techniques and verification since the beginning of the trial are summarised in table 1. Table 1 Figure 1 *Note that some centres reported using more than one beam arrangement, beam energy, planning algorithm or treatment verification technique. Out of the 34 clinicians who answered the questionnaire, 14 (41.1%) are currently using 4DCT, 3 (8.8%) are using breathold techniques and 16 (47.1%) are not using any technique to account for respiratory motion for simulation and treatment planning of lung patients. Data on management of respiratory motion were not available in 2008.

      Conclusion
      During the 5 years the CONVERT Trial has been open there have been significant advances in radiotherapy treatment technology. Major changes include the use of Type B treatment planning algorithms and PET CT for planning, IMRT for treatment and CBCT for treatment verification of patients with small cell lung cancer.

      Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.

  • +

    P3.08 - Poster Session 3 - Radiotherapy (ID 199)

    • Event: WCLC 2013
    • Type: Poster Session
    • Track: Radiation Oncology + Radiotherapy
    • Presentations: 1
    • +

      P3.08-012 - I-START Trial: A UK phase I/II trial of isotoxic accelerated radiotherapy in locally advanced non-small cell lung cancer (ID 1575)

      09:30 - 16:30  |  Author(s): N. Mohammed

      • Abstract

      Background
      Approximately 35,000 people die from lung cancer each year in the UK, the majority from non-small cell lung cancer (NSCLC). Patients with locally advanced (LA) NSCLC are often not suitable for chemotherapy or combined chemo-radiotherapy treatment because of patient or tumour factors. In these cases radical radiotherapy alone is used. Increased radiation dose may improve both local tumour control and survival. The radiotherapy dose is limited by surrounding organs, which include the lungs, heart, spinal cord and oesophagus. The maximum radiotherapy dose that can safely be delivered to the oesophagus is not known. The I-START trial was therefore developed, on behalf of the UK National Cancer Research Institute Lung Clinical Studies Group, to establish oesophageal radiation dose limits and to investigate the feasibility and effectiveness of a novel approach to dose escalation in LA-NSCLC. The study is funded by Cancer Research UK (C25518/A11535), sponsored by Velindre NHS Trust and coordinated by the Wales Cancer Trials Unit.

      Methods
      Patients with histologically or cytologically confirmed stage II to IIIb NSCLC, suitable for radical radiotherapy, are eligible for the trial. Enrolled patients will receive 20 fractions of radiotherapy over 4 weeks. The trial is split into two phases: Phase I: To establish the maximum tolerated (MTD) dose of radiotherapy to the oesophagus in patients where the oesophagus overlaps with the planning target volume (PTV). Phase I patients will be split into 2 groups depending on the length of the oesophagus lying within the PTV (Group 1A is where the overlap ≤6.5cm and Group 1B is where the overlap >6.5cm). Cohorts of 6 or 12 patients are recruited to both groups at sequentially increasing dose levels (58, 61, 63, 65Gy). Progression to the next oesophageal dose level will depend on the number of patients in a cohort with grade 3 or 4 acute oesophagitis, or other grade 3 or 4 toxicity, occurring up to 2 months after radiotherapy. Once the MTD to the oesophagus is established for each group, all participants will follow the Phase II protocol with the determined oesophageal dose limit. Phase II: Patients will receive a maximum of 65Gy in 20 fractions and the dose prescribed will be the highest dose achievable without exceeding defined safe dose limits for organs at risk. Where the oesophagus does not overlap with the PTV, patients can immediately be treated in Phase II, whereas patients whose oesophagus overlaps with the PTV can only be entered into Phase II once Phase I is complete, i.e. the MTD to the oesophagus has been established. The primary outcome of Phase II is the toxicity rate (grade 3 or 4) at 3 months. The I-START trial will determine whether this novel method of increasing the radiotherapy dose in patients with NSCLC patients is tolerable, safe and effective. If the results are positive, then this new treatment may be compared against the best currently available standard treatment in a future larger randomised (Phase III) trial.

      Results
      Not applicable.

      Conclusion
      Not applicable.

  • +

    P3.13 - Poster Session 3 - SCLC (ID 202)

    • Event: WCLC 2013
    • Type: Poster Session
    • Track: Medical Oncology
    • Presentations: 1
    • +

      P3.13-005 - CONVERT - the challenges of opening centres and recruiting patients to an international multi-centre chemo-radiotherapy trial in limited-stage small cell lung cancer (ID 1366)

      09:30 - 16:30  |  Author(s): N. Mohammed

      • Abstract

      Background
      CONVERT is a multicentre, randomised, phase III trial open in Europe and Canada in limited-stage small cell lung cancer. Patients are randomised to twice (45 Gy in 30 fractions) or once-daily radiotherapy (66 Gy in 33 fractions) given concurrently with 4-6 cycles of chemotherapy. This study is funded by Cancer Research UK and involves centres from the UK NCRI, the ‘Groupe Francais de Pneumo-Cancerologie’, the Spanish Lung Cancer Group, the EORTC and NCIC CTG.

      Methods
      To identify and review the challenges in site set-up. To review time taken from site initiation to first patient randomised, number of centres opened that included 0-2 patients and number of centres that recruited the majority of all patients.

      Results
      In June 2013, 519/532 patients had been recruited in 9 countries; 299 from 32 UK centres, 100 from 17 French centres, 39 from 9 Canadian centres, 27 from 6 Spanish centres, 26 from 3 Belgian centres, 13 patients from 1 centre in Slovenia, 9 from 2 centres in The Netherlands and 6 patients from 1 centre in Poland. Figure 1 shows the number of centres open and patients recruited. 96 sites are currently open to recruitment (5 sites opened in 2008, 34 in 2009, 31 in 2010, 17 in 2011, 8 in 2012 & 3 in 2013, 2 sites subsequently closed early) of which 74 (77%) have randomised at least 1 patient. 24 sites (25%) recruited only 1 or 2 patients. 10 sites have recruited 49% of the total number of patients with a single site recruiting 18.5% of all patients randomised. Time taken from site initiation to 1[st] patient randomised ranged from 0–1029 days with a median of 144 days. Time taken to complete the QA exercise from initial information sent to site ranged from 14-1181 days with a median of 290.5 days. Figure 1

      Conclusion
      Recruitment to an academic trial in LS-SCLC is a challenge but accrual has improved considerably since 2008. This can be directly related to the increasing number of sites opened to recruitment. Duration of site set-up and completion of the QA exercise are factors explaining slower than anticipated accrual rates particularly between 2008 and 2010. We anticipate that the study will close to recruitment in July 2013. International participation has been a key factor to the success of the trial and the experience gained will be of value to the design of future radiotherapy studies to ensure target accrual.