Sentinel lymph node imaging guided IMRT for prostate cancer: Individualized pelvic radiation therapy versus RTOG guidelines.

PURPOSE/OBJECTIVES: Current Radiation Therapy Oncology Group (RTOG) guidelines for pelvic radiation therapy are based on general anatomic boundaries. Sentinel lymph node (SLN) imaging can identify potential sites of lymph node involvement. We sought to determine how tailored radiation therapy fields for prostate cancer would compare to standard RTOG-based fields. Such individualized radiation therapy could prioritize the most important areas to irradiate while potentially avoiding coverage in areas where critical structures would be overdosed. Individualized radiation therapy could therefore increase the therapeutic index of pelvic radiation therapy. METHODS AND MATERIALS: Ten intermediate or high-risk prostate cancer patients received androgen deprivation therapy with definitive radiation therapy, including an SLN imaging-tailored elective nodal volume (ENV). For dosimetric analyses, the ENV was recontoured using RTOG guidelines (RTOG_ENV) and on SLNs alone (SLN_ENV). Separate intensity modulated radiation therapy (IMRT) plans were optimized using RTOG_ENV and SLN_ENV for each patient. Dosimetric comparisons for these IMRT plans were performed for each patient. Dose differences to targets and critical structures among the different IMRT plans were calculated. Distributions of dose parameters were analyzed using non-parametric methods. RESULTS: Sixty percent of patients had SLNs outside of the RTOG_ENV. The larger volume IMRT plans covering SLN imaging-tailored elective nodal volume exhibited no significant dose differences versus plans covering RTOG_ENV. IMRT plans covering only the SLNs had significantly lower doses to bowel and femoral heads. CONCLUSIONS: SLN-guided pelvic radiation therapy can be used to either treat the most critical nodes only or as an addition to RTOG guided pelvic radiation therapy to ensure that the most important nodes are included.

Quality improvement of International Classification of Diseases, 9th revision, diagnosis coding in radiation oncology: single-institution prospective study at University of California, San Francisco.

PURPOSE: Accurate International Classification of Diseases (ICD) diagnosis coding is critical for patient care, billing purposes, and research endeavors. In this single-institution study, we evaluated our baseline ICD-9 (9th revision) diagnosis coding accuracy, identified the most common errors contributing to inaccurate coding, and implemented a multimodality strategy to improve radiation oncology coding. METHODS AND MATERIALS: We prospectively studied ICD-9 coding accuracy in our radiation therapy--specific electronic medical record system. Baseline ICD-9 coding accuracy was obtained from chart review targeting ICD-9 coding accuracy of all patients treated at our institution between March and June of 2010. To improve performance an educational session highlighted common coding errors, and a user-friendly software tool, RadOnc ICD Search, version 1.0, for coding radiation oncology specific diagnoses was implemented. We then prospectively analyzed ICD-9 coding accuracy for all patients treated from July 2010 to June 2011, with the goal of maintaining 80% or higher coding accuracy. Data on coding accuracy were analyzed and fed back monthly to individual providers. RESULTS: Baseline coding accuracy for physicians was 463 of 661 (70%) cases. Only 46% of physicians had coding accuracy above 80%. The most common errors involved metastatic cases, whereby primary or secondary site ICD-9 codes were either incorrect or missing, and special procedures such as stereotactic radiosurgery cases. After implementing our project, overall coding accuracy rose to 92% (range, 86%-96%). The median accuracy for all physicians was 93% (range, 77%-100%) with only 1 attending having accuracy below 80%. Incorrect primary and secondary ICD-9 codes in metastatic cases showed the most significant improvement (10% vs 2% after intervention). CONCLUSIONS: Identifying common coding errors and implementing both education and systems changes led to significantly improved coding accuracy. This quality assurance project highlights the potential problem of ICD-9 coding accuracy by physicians and offers an approach to effectively address this shortcoming.

Implications of delayed initiation of radiotherapy: accelerated repopulation after induction chemotherapy for stage III non-small cell lung cancer.

INTRODUCTION: For patients with stage III non-small cell lung cancer treated with induction chemotherapy (ICT), delayed initiation of subsequent radiotherapy (RT) may allow for repopulation in the interval between treatment modalities and during the early phase of RT. We quantified the impact of postinduction RT timing by evaluating the pace of tumor regrowth. METHODS: Institutionally approved retrospective review identified 21 analyzable patients with stage III non-small cell lung cancer who had platinum-based ICT followed by RT+/- chemotherapy from 2002 to 2009. Radiographic response was determined by RECIST criteria and the volume of the single largest tumor mass on the pre-ICT, post-ICT, and RT-planning computed tomography scans. RESULTS: After ICT, the median percent volume change from pre-ICT baseline was -41% (range -86 to +86%). By the RT-planning computed tomography scan, the median percent volume change from the post-ICT timepoint was +40% (range -11 to +311%) and the median volume change was +20 ml (range -4 to 102 ml); these changes were significant (p = 0.0002). Similar results were seen for tumor diameter. A correlation was observed between the amount of delay and degree of regrowth for percent volume (p = 0.0006) and percent diameter change (p = 0.003). A delay greater than 21 days produced greater increases in percent volume change (p = 0.002) and percent diameter (p = 0.055) than lesser delays. CONCLUSIONS: After ICT, tumor regrowth can occur within a few weeks. Radiation treatment planning should begin as soon as possible after the administration of ICT to maximize the benefits of cytoreduction.