The TeleStroke mimic (TM)-score: a prediction rule for identifying stroke mimics evaluated in a Telestroke Network.

BACKGROUND: Up to 30% of acute stroke evaluations are deemed stroke mimics (SM). As telestroke consultation expands across the world, increasing numbers of SM patients are likely being evaluated via Telestroke. We developed a model to prospectively identify ischemic SMs during Telestroke evaluation. METHODS AND RESULTS: We analyzed 829 consecutive patients from January 2004 to April 2013 in our internal New England-based Partners TeleStroke Network for a derivation cohort, and 332 cases for internal validation. External validation was performed on 226 cases from January 2008 to August 2012 in the Partners National TeleStroke Network. A predictive score was developed using stepwise logistic regression, and its performance was assessed using receiver-operating characteristic (ROC) curve analysis. There were 23% SM in the derivation, 24% in the internal, and 22% in external validation cohorts based on final clinical diagnosis. Compared to those with ischemic cerebrovascular disease (iCVD), SM had lower mean age, fewer vascular risk factors, more frequent prior seizure, and a different profile of presenting symptoms. The TeleStroke Mimic Score (TM-Score) was based on factors independently associated with SM status including age, medical history (atrial fibrillation, hypertension, seizures), facial weakness, and National Institutes of Health Stroke Scale >14. The TM-Score performed well on ROC curve analysis (derivation cohort AUC=0.75, internal validation AUC=0.71, external validation AUC=0.77). CONCLUSIONS: SMs differ substantially from their iCVD counterparts in their vascular risk profiles and other characteristics. Decision-support tools based on predictive models, such as our TM Score, may help clinicians consider alternate diagnosis and potentially detect SMs during complex, time-critical telestroke evaluations.

Prognostic accuracy of computed tomography findings for patients with laryngeal cancer undergoing laryngectomy.

PURPOSE: The indications for upfront laryngectomy in the management of laryngeal cancer are a functionless larynx and extralaryngeal extension. Practically, clinicians rely on imaging to predict which patients will have T4 disease. Our goal was to review the accuracy of preoperative computed tomography (CT) scanning in determining the necessity for initial laryngectomy for advanced laryngeal cancer. PATIENTS AND METHODS: In total, 107 consecutive untreated laryngectomy specimens with high-quality, preoperative CT imaging interpreted by our neuroradiologists were reviewed. Radiographic findings, including sclerosis, invasion, penetration, extralaryngeal spread, and subglottic extension were correlated with pathologic findings. CT images were not reinterpreted, since our purpose was to assess the original interpretations. RESULTS: CT imaging reported 23 cases of thyroid cartilage penetration and 27 cases of extralaryngeal spread. Pathology reported 12 cases of thyroid cartilage invasion, 29 cases of penetration, and 45 cases of extralaryngeal disease. CT imaging identified 17 (59%) of 29 cases of pathologically documented thyroid cartilage penetration and 22 (49%) of 45 cases of pathologically documented extralaryngeal spread. Pathologically proven extralaryngeal spread without thyroid cartilage penetration occurred in 18 (40%) of 45 cases. The positive predictive values for thyroid cartilage penetration and extralaryngeal spread were 74% and 81%. Sclerosis was of limited value in predicting thyroid cartilage invasion or penetration. Cricoid or arytenoid destruction predicted for thyroid cartilage penetration at rates of 57% and 63%. CONCLUSION: CT imaging has clear limitations when deciding whether there is thyroid cartilage penetration or extralaryngeal spread of advanced laryngeal cancer. Extralaryngeal spread without thyroid cartilage penetration was more common than expected. Alternate methods of pretreatment assessment are needed.

Three-year outcomes of breast intensity-modulated radiation therapy with simultaneous integrated boost.

PURPOSE: To report our clinical experience using breast intensity-modulated radiation therapy with simultaneous integrated boost (SIB-IMRT). METHODS AND MATERIALS: Retrospective review identified 354 Stage 0 to III breast cancer patients treated with SIB-IMRT after conservative surgery between 2003 and 2006. The most common fractionation (89%) simultaneously delivered 1.8 Gy to the ipsilateral breast tissue and 2.14 Gy to the resection cavity, yielding a breast dose of 45 Gy (25 fractions) and cavity dose 59.92 Gy (28 fractions), biologically equivalent for tumor control to 45 Gy to the breast with sequential 16-Gy boost (33 fractions). RESULTS: A total of 356 breasts in 354 patients were treated: 282 with invasive breast cancer, and 74 with ductal carcinoma in situ (DCIS). For left breast radiation, median cardiac V(15) was 2.9% and left ventricular V(15) 1.7%. Median follow-up was 33 months (range, 4-73 months). Acute toxicity was Grade 1 in 57% of cases, Grade 2 in 43%, and Grade 3 in <1%. For invasive breast cancer, the 3-year overall survival was 97.6% and risk of any locoregional recurrence was 2.8%. For ductal carcinoma in situ, 3-year overall survival was 98% and risk of locoregional recurrence 1.4%. In 142 cases at a minimum of 3 years follow-up, global breast cosmesis was judged by physicians as good or excellent in 96.5% and fair in 3.5%. CONCLUSIONS: Breast SIB-IMRT reduced treatment duration by five fractions with a favorable acute toxicity profile and low cardiac dose for left breast treatment. At 3 years, locoregional control was excellent, and initial assessment suggested good or excellent cosmesis in a high percentage of evaluable patients.

Concurrent chemotherapy with intensity-modulated radiation therapy for locally advanced squamous cell carcinoma of the larynx and oropharynx: a retrospective single-institution analysis.

BACKGROUND: We present outcome data from concurrent chemotherapy and intensity-modulated radiation therapy (IMRT) for squamous cell carcinoma (SCC) of the larynx and oropharyx. METHODS: Eighty patients with laryngeal (n = 15) or oropharyngeal (n = 65) SCC underwent concurrent IMRT and chemotherapy (cisplatin or carboplatin/paclitaxel). RESULTS: The 3-year overall survival (OS) and disease-free survival (DFS) were 81.2% and 78.3%, respectively, with a median follow-up of 31.2 months. There was a statistically significant correlation between OS and DFS with N classification (p = .0001), but not with disease site or T classification. Toxicities compared favorably with prior reports using conventional radiation therapy. CONCLUSIONS: This retrospective analysis reveals a very good outcome and an acceptable toxicity profile for patients with locally advanced SCC of the oropharynx and larynx treated with chemotherapy and IMRT concurrently.

Long-term outcomes of IMRT for breast cancer: a single-institution cohort analysis.

PURPOSE: To evaluate long-term outcomes of adjuvant breast intensity-modulated radiation therapy (IMRT), with a comparison cohort receiving conventional radiation (cRT) during the same period. METHODS AND MATERIALS: Retrospective review identified patients with Stages 0-III breast cancer who underwent irradiation after conservative surgery from January 1999 to December 2003. Computed tomography simulation was used to design standard tangential breast fields with enhanced dynamic wedges for cRT and both enhanced dynamic wedges and dynamic multileaf collimators for IMRT. Patients received 1.8-2-Gy fractions to 44-50.4 Gy to the whole breast, followed by an electron boost of 10-20 Gy. RESULTS: A total of 245 breasts were treated in 240 patients: 121 with IMRT and 124 with cRT. Median breast dose was 50 Gy, and median total dose was 60 Gy in both groups. Patient characteristics were well balanced between groups. Median follow-ups were 6.3 years (range, 3.7-104 months) for patients treated with IMRT and 7.5 years (range, 4.9-112 months) for those treated with cRT. Treatment with IMRT decreased acute skin toxicity of Radiation Therapy Oncology Group Grade 2 or 3 compared with cRT (39% vs. 52%; p = 0.047). For patients with Stages I-III (n = 199), 7-year Kaplan-Meier freedom from ipsilateral breast tumor recurrence (IBTR) rates were 95% for IMRT and 90% for cRT (p = 0.36). For patients with Stage 0 (ductal carcinoma in situ, n = 46), 7-year freedom from IBTR rates were 92% for IMRT and 81% for cRT (p = 0.29). Comparing IMRT with cRT, there were no statistically significant differences in overall survival, disease-specific survival, or freedom from IBTR, contralateral breast tumor recurrence, distant metastasis, late toxicity, or second malignancies. CONCLUSIONS: Patients treated with breast IMRT had decreased acute skin toxicity, and long-term follow-up shows excellent local control similar to a contemporaneous cohort treated with cRT.

Integration of databases for radiotherapy outcomes analyses.

The technical nature of radiotherapy requires different data collection strategies for outcomes reporting than those required for most other disciplines in clinical medicine. To correlate advances in radiotherapy technology with treatment outcomes, it is necessary to integrate a given radiotherapy outcomes-study database with the record-and-verify database and with the global hospital database. The authors review the recent development of each of these categories of databases from the vantage point of radiotherapy. Their goal was to integrate these 3 databases for outcomes analyses in radiotherapy at their institution; this process involved (1) the construction of an interface between the record-and-verify database and the outcomes-study database and (2) the use of a bioinformatics database linking the outcomes-study database and the global hospital database. This bioinformatics database was successfully queried in a manner that allowed streamlining data flow of relevance to radiotherapy outcomes studies. Future directions of the application of this integration are discussed.

Clinical implementation and efficiency of kilovoltage image-guided radiation therapy.

This paper describes measurements of clinical efficiency and time requirements associated with image-guided radiation therapy (IGRT). In June 2004, the authors' institution installed an integrated kilovoltage (kV) imaging system attached to a medical linear accelerator for radiographic target localization. Over the past year, 242 patients have been localized with the kV radiographic imaging system for a total of 2,700 fractions. Data were analyzed by reviewing the time required for each patient's IGRT session, broken into both image acquisition and image analysis time. Average IGRT procedure time was reviewed pertaining to months, treatment sessions, disease sites, and radiation therapists. Results showed that the average IGRT procedure time was reduced from 450 to 237 seconds from June 2004 to June 2005. Further analysis revealed that each therapist showed improvement in reducing the IGRT procedure time from the first month of use to the month of June 2005. The routine use of IGRT may ultimately be performed within 3 to 4 minutes, with minimal disruption to the clinical treatment process.

Measurements of secondary neutron dose from 15 MV and 18 MV IMRT.

Secondary neutron dose-equivalents were determined for conventional and intensity modulated radiation therapy (IMRT) prostate treatments for 15 and 18 MV X-ray beams. Conventional and IMRT treatment plans were generated to deliver 45 Gy to the prostate, seminal vessicles and external and internal iliac lymph nodes. Neutron spectra were determined by unfolding measurements from a TLD-based Bonner sphere system. Treatments using 18 MV IMRT and conventional plans result in neutron ambient dose-equivalents of 687 and 112 mSv, respectively. Delivery of the 15 MV IMRT and conventional plans results in neutron ambient dose-equivalents of 327 and 52 mSv, respectively. The data illustrate that using lower photon energies for IMRT reduces the secondary neutron dose, while still achieving comparable treatment volume coverage and sparing critical normal tissue.

Intracranial arteriovenous malformations treated utilizing a linear accelerator-based patient rotator or commercially available radiosurgery system.

PURPOSE: To report a single-institution experience with intracranial arteriovenous malformations (AVMs) treated utilizing a linear accelerator-based patient rotator (PR) or BrainLAB (BL) radiosurgery system (BrainLAB AG, Heimstetten, Germany). METHODS AND MATERIALS: Since 1989, 84 evaluable patients were treated. PR patients (n = 45) were planned/localized on the basis of biplane angiography and treated between 1989 and 2000. BL patients (n = 39) were planned/localized on the basis of CT/MRI and treated since 2000. Kaplan-Meier analyses of survival, nidus obliteration (NO), and any radiographic improvement were undertaken with Cox regression of dose and volume effects. RESULTS: No significant complication, survival, previous embolization incidence, AVM location or size differences existed between BL/PR patients. The groups differed significantly in prescribed dose (PR: 16.2 Gy, BL: 17.3 Gy, p = 0.004) and isodose (PR: 62%, BL: 79%, p < 0.0001). Estimated 2-year NO rate was 87% for BL patients, 12% for PR patients (p < 0.0001). Ultimate PR NO rate was 67% at 6 years. Dose (p = 0.037) and isodose (p = 0.014) significantly affected PR NO outcome; volume was of borderline significance (p = 0.069). No factors significantly affected BL outcome. Analyses of small (< or = 4.0 cm3), high-dose (> or = 17.0 Gy) PR patients (PR1 group) vs. BL patients still demonstrated greater NO (p = 0.04) and radiographic improvement (p = 0.0004) rates for the BL group. PR1 patients had a 76% 3-year NO rate. CONCLUSIONS: BL-based radiosurgery achieved a high NO rate, the PR method did not. Differences in outcomes between PR/BL groups may be due to localization methods or an inherent advantage with the BL system.

Comparison of CT- and FDG-PET-defined gross tumor volume in intensity-modulated radiotherapy for head-and-neck cancer.

PURPOSE: To compare the gross tumor volume (GTV) identified on CT to that obtained from fluorodeoxyglucose (FDG) positron emission tomography (PET) and determine the differences in volume and dose coverage of the PET-GTV when the CT-GTV is used for radiotherapy planning. METHODS AND MATERIALS: A total of 40 patients with intact squamous cell carcinoma arising in the head-and-neck region underwent intensity-modulated radiotherapy (IMRT) at one department. All patients underwent CT simulation for treatment planning followed by PET-CT in the treatment position. CT simulation images were fused to the CT component of the PET-CT images. The GTV using the CT simulation images was contoured (CT-GTV), as was the GTV based on the PET scan (PET-GTV). The IMRT plans were obtained using the CT-GTV. RESULTS: The PET-GTV was smaller, the same size, and larger than the CT-GTV in 30 (75%), 3 (8%), and 7 (18%) cases respectively. The median PET-GTV and CT-GTV volume was 20.3 cm(3) (range, 0.2-294) and 37.2 cm(3) (range, 2-456), respectively. The volume of PET-GTV receiving at least 95% of the prescribed dose was 100% in 20 (50%), 95-99% in 10 (25%), 90-94% in 3 (8%), 85-89% in 1 (3%), 80-84% in 2 (5%), 75-79% in 1 (3%), and <75% in 3 (8%) cases. The minimal dose received by 95% of the PET-GTV was >/=100% in 19 (48%), 95-99% in 11 (28%), 90-94% in 5 (13%), 85-89% in 2 (5%), and <75% in 3 (8%) cases. CONCLUSION: The PET-GTV was larger than the CT-GTV in 18% of cases. In approximately 25% of patients with intact head-and-neck cancer treated using IMRT, the volume of PET-GTV receiving at least 95% of the prescribed dose and minimal dose received by 95% of the PET-GTV were less than optimal.

F-18 FDG PET-CT fusion in radiotherapy treatment planning for head and neck cancer.

BACKGROUND: The fusion of fluoro-2-deoxy-D-glucose-positron emission tomography (FDG-PET) with CT scans has been shown to improve diagnostic accuracy and staging in non-small cell lung cancer. We report on the influence of PET-CT fusion on the management of patients with head and neck cancer. METHODS: Thirty-six patients with intact primary head and neck cancers treated with radiation therapy (RT) received PET-CT as part of treatment planning. Workup before PET-CT included a contrast-enhanced CT scan of the head and neck and chest X-ray; patients with nasopharyngeal and paranasal sinus primary tumors also underwent MRI. RESULTS: Changes in TNM score and American Joint Committee on Cancer stage occurred in 13 patients (36%) and five patients (14%), respectively, based on PET-CT. RT volume and dose were altered in five patients (14%) and four patients (11%), respectively. Five patients initially were seen with carcinoma of unknown primary, and PET-CT confirmed oropharyngeal primary tumors in two. PET-CT data also detected a synchronous lung cancer in one patient. CONCLUSION: PET-CT fusion may have a significant impact on staging and determination of RT treatment volume and dose.

Maintenance of certification.

Maintenance of certification (MOC) recognizes that in addition to medical knowledge, several essential elements involved in delivering quality care must be developed and maintained throughout one's career. The MOC process is designed to facilitate and document the professional development of each American Board of Radiology (ABR) diplomate through its focus on the essential elements of quality care in diagnostic radiology, its subspecialties, radiation oncology, and radiologic physics. The initial elements of the ABR's MOC program have been developed in accord with guidelines of the American Board of Medical Specialties. Further details will be developed as the process evolves.

Black and white patients fare equally well when treated with postlumpectomy radiotherapy.

PURPOSE: Some previous studies have demonstrated that black patients have inferior local-regional control and disease-free survival when treated with postlumpectomy radiotherapy. The intention of this study was to analyze the same outcomes with a larger series of black patients. METHODS: A retrospective chart review was performed at an academic referral center, a community hospital, and an inner-city public hospital. RESULTS: A total of 270 patients that received postlumpectomy radiotherapy were reviewed. Of those, 102 were black, 162 white, and six nonblack, nonwhite. The black patients were statistically significantly more likely to present with higher-stage disease (Stage II: 43.1% vs. 32.1%), positive lymph nodes (29.4% vs. 14.8%), higher-grade disease (Grade III: 35.3% vs. 24.1%), and age < 45. The actuarial local control at five years in the black patients was 95.5% and in the white patients was 94.8%. The actuarial five-year disease-free survival in the black patients was 90.3% and in the white patients was 91.7%. There was no statistically significant difference in either local control or disease free-survival in the black and white patients when matched by stage. CONCLUSION: At five years, the local control and disease-free survival for black patients are equally as good as white patients.

Extra-target doses in children receiving multileaf collimator (MLC) based intensity modulated radiation therapy (IMRT).

PURPOSE: To investigate the extra-target doses using intensity modulated radiation therapy (IMRT). MATERIALS AND METHODS: Thirteen children underwent multileaf collimator (MLC)-based IMRT. Treatment site was head and neck or brain in eight (Group I), trunk in two (Group II), and abdomen/pelvis in three (Group III). Thermoluminescent dosimeters (TLD) were placed at the thyroid gland, breast, and testis. A control group of seven children received conventional RT and TLD measurements. RESULTS: For the eight Group I children, the median dose equivalent measurements during the course of IMRT to the thyroid, breast, and testis were 348 mSv, 110 mSv, and 30 mSv, respectively. For the two Group II patients, the measurements to the thyroid ranged from 1,525 to 2,449 mSv while for the testis was 62 mSv. For the Group III patients, the median dose equivalent measurements to the thyroid, breast, and testis were 182 mSv, 406 mSv, and 159 mSv. The median dose equivalent measurements to the thyroid, breast, and testis for Group I children were 300 mSv, 120 mSv, and 75 mSv. The Group II conventional patient had a measurement of 180 mSv, 80 mSv, and 80 mSv to the thyroid, breast, and testis. For the Group III conventional cases, the median dose equivalent measurements were 192 mSv, 496 mSv, and 434 mSv. CONCLUSIONS: No significant difference was seen in the thyroid and breast doses of children receiving MLC-based IMRT compared to conventional RT for the treatment of head and neck/brain and abdominal/pelvic tumors.

Intensity modulated radiation therapy for retroperitoneal sarcoma: a case for dose escalation and organ at risk toxicity reduction.

PURPOSE: Radiation therapy for retroperitoneal sarcoma remains challenging because of proximity to surrounding organs at risk (OAR). We report the use of intensity modulated radiation therapy (IMRT) in the treatment of retroperitoneal sarcomas to minimize dose to OAR while concurrently optimizing tumor dose coverage. PATIENTS AND METHODS: From January 2000 to October 2002, 10 patients (average age 56 years) with retroperitoneal sarcoma and one with inguinal sarcoma were treated with radiation at Emory University. Prescription dose to the planning treatment volume (PTV) was commonly 50.4 at 1.8 Gy/fraction. CT simulation was used in each patient, three patients were treated with 3D-conformal treatment (3D-CRT), and the remaining eight received multi-leaf collimator-based (MLC) IMRT. IMRT treatment fields ranged from eight to 11 and average volume treated was 3498 cc. Optimal 3D-CRT plans were generated and compared with IMRT with respect to tumor coverage and OAR dose toxicity. Dose volume histograms were compared for both the 3D-CRT and IMRT plans. RESULTS: Mean dose to small bowel decreased from 36 Gy with 3D-CRT to 27 Gy using IMRT, and tumor coverage (V95) increased from 95.3% with 3D-CRT to 98.6% using IMRT. Maximum and minimum doses delivered to the PTV were significantly increased by 6 and 22%, respectively (P = 0.011, P = 0.055). Volume of small bowel receiving > 30Gy was significantly decreased from 63.5 to 43.1% with IMRT compared with conventional treatment (P = 0.043). Seven patients developed grade 2 nausea, three developed grade 2 diarrhea, one had grade 2 skin toxicity, and one patient developed grade 3 liver toxicity (RTOG toxicity scale). No other delayed toxicities related to radiation were observed. At a median follow-up of 58 weeks, there were no local recurrences and only one patient developed disease progression with distant metastasis in the liver. CONCLUSIONS: IMRT for retroperitoneal sarcoma allowed enhanced tumor coverage and better sparing of dose to critical normal structures such as small bowel, liver, and kidney. Escalation of dose has a positive impact on local control for retroperitoneal sarcoma; IMRT may be an effective method to achieve this goal. We are evaluating preoperative dose escalation to 59.4 Gy.

Treatment of pancreatic cancer tumors with intensity-modulated radiation therapy (IMRT) using the volume at risk approach (VARA): employing dose-volume histogram (DVH) and normal tissue complication probability (NTCP) to evaluate small bowel toxicity.

The emergent use of a combined modality approach (chemotherapy and radiation) in pancreatic cancer is associated with increased gastrointestinal toxicity. Intensity-modulated radiation therapy (IMRT) has the potential to deliver adequate dose to the tumor volume while decreasing the dose to critical structures such as the small bowel. We evaluated the influence of IMRT with inverse treatment planning on the dose-volume histograms (DVHs) of normal tissue compared to standard 3-dimensional conformal radiation treatment (3D-CRT) in patients with pancreatic cancer. Between July 1999 and May 2001, 10 randomly selected patients with adenocarcinoma of the pancreatic head were planned simultaneously with 3D-CRT and inverse-planned IMRT using the volume at risk approach (VaRA) and compared for various dosimetric parameters. DVH and normal tissue complication probability (NTCP) were calculated using IMRT and 3D-CRT plans. The aim of the treatment plan was to deliver 61.2 Gy to the gross tumor volume (GTV) and 45 Gy to the clinical treatment volume (CTV) while maintaining critical normal tissues to below specified tolerances. IMRT plans were more conformal than 3D-CRT plans. The average dose delivered to one third of the small bowel was lower with the IMRT plan compared to 3D-CRT. The IMRT plan resulted in one third of the small bowel receiving 30.2+/-12.9 Gy vs. 38.5+/-14.2 Gy with 3D-CRT (p = 0.006). The median volume of small bowel that received greater than either 50 or 60 Gy was reduced with IMRT. The median volume of small bowel exceeding 50 Gy was 19.2+/-11.2% (range 3% to 45%) compared to 31.4+/-21.3 (range 7% to 70%) for 3D-CRT (p = 0.048). The median volume of small bowel that received greater than 60 Gy was 12.5+/-4.8% for IMRT compared to 19.8+/-18.6% for 3D-CRT (p = 0.034). The VaRA approach employing IMRT techniques resulted in a lower dose per volume of small bowel that exceeded 60 Gy. We used the Lyman-Kutcher models to compare the probability of small bowel injury employing IMRT compared to 3D-CRT. The BIOPLAN model predicted a small bowel complication probability of 9.3+/-6% with IMRT compared to 24.4+/-18.9% with 3D-CRT delivery of dose (p = 0.021). IMRT with an inverse treatment plan has the potential to significantly improve radiation therapy of pancreatic cancers by reducing normal tissue dose, and simultaneously allow escalation of dose to further enhance locoregional control.