Functional liver image guided hepatic therapy (FLIGHT) with hepatobiliary iminodiacetic acid (HIDA) scans.

PURPOSE: Hepatobiliary iminodiacetic acid (HIDA) scans provide global and regional assessments of liver function that can serve as a road map for functional avoidance in stereotactic body radiation therapy (SBRT) planning. Functional liver image guided hepatic therapy (FLIGHT), an innovative planning technique, is described and compared with standard planning using functional dose-volume histograms. Thresholds predicting for decompensation during follow up are evaluated. METHODS AND MATERIALS: We studied 17 patients who underwent HIDA scans before SBRT. All SBRT cases were replanned using FLIGHT. The following dosimetric endpoints were compared for FLIGHT versus standard SBRT planning: functional residual capacity <15 Gy (FRC15HIDA), mean liver dose (MLD), equivalent uniform dose (EUD), and functional EUD (FEUD). Receiver operating characteristics curves were used to evaluate whether baseline HIDA values, standard cirrhosis scoring, and/or dosimetric data predicted clinical decompensation. RESULTS: Compared with standard planning, FLIGHT significantly improved FRC15HIDA (mean improvement: 5.3%) as well as MLD, EUD, and FEUD (P < .05). Considerable interindividual variations in the extent of benefit were noted. Decompensation during follow-up was associated with baseline global HIDA <2.915%/min/m2, FRC15HIDA <2.11%/min/m2, and MELD ≥11 (P < .05). CONCLUSIONS: FLIGHT with HIDA-based parameters may complement blood chemistry-based assessments of liver function and facilitate individualized, adaptive liver SBRT planning.

Cost analysis of adjuvant management strategies in early stage (stage I) testicular seminoma.

BACKGROUND: Acceptable post-orchiectomy adjuvant therapy strategies for stage I seminoma patients include surveillance, para-aortic radiation therapy (RT), dog-leg RT, and a single cycle of carboplatin. The required follow-up recommendations were amended by the National Comprehensive Cancer Network (NCCN) in 2012. Given a cause-specific survival of nearly 100%, a closer analysis of the reimbursement for each treatment strategy is warranted. METHODS: NCCN guidelines were used to design treatment plans for each acceptable adjuvant treatment strategy. Follow-up charges were generated for 10 years based on 2012 (version 1.2012; unchanged in current version 1.2013) and 2011 NCCN (version 2.2011) surveillance recommendations. The 2012 Medicare reimbursement rates were used to calculate each treatment strategy and incremental cost-effectiveness ratios to compare the treatment options. RESULTS: Under the current NCCN follow-up recommendations, the total reimbursements generated over 10 years of surveillance, para-aortic RT, dog-leg RT, and carboplatin were $10,643, $11,678, $9,662, and $10,405, respectively. This is compared with the reimbursements as per the 2011 NCCN recommendations: $20,986, $11,517, $9,394, and $20,365 respectively. Factoring the rates of relapse into a salvage model, observation was found to be more costly and less effective ($-1,831, $-7,318, $-7,010) in the adjuvant management of stage I seminoma patients. CONCLUSION: Based on incremental cost-effectiveness ratios, para-aortic RT, dog-leg RT, and carboplatin are cost-effective options for the treatment of stage I seminoma when compared with observation; however, surveillance could potentially spare as many as 80%-85% of men diagnosed with stage I seminoma from additional therapy after radical inguinal orchiectomy. Such cost and reimbursement analyses are becoming increasingly relevant, but are not meant to usurp sound clinical judgment. Further studies are required to validate these findings.

Improved human observer performance in digital reconstructed radiograph verification in head and neck cancer radiotherapy.

PURPOSE: Digitally reconstructed radiographs (DRRs) are routinely used as an a priori reference for setup correction in radiotherapy. The spatial resolution of DRRs may be improved to reduce setup error in fractionated radiotherapy treatment protocols. The influence of finer CT slice thickness reconstruction (STR) and resultant increased resolution DRRs on physician setup accuracy was prospectively evaluated. METHODS: Four head and neck patient CT-simulation images were acquired and used to create DRR cohorts by varying STRs at 0.5, 1, 2, 2.5, and 3 mm. DRRs were displaced relative to a fixed isocenter using 0-5 mm random shifts in the three cardinal axes. Physician observers reviewed DRRs of varying STRs and displacements and then aligned reference and test DRRs replicating daily KV imaging workflow. A total of 1,064 images were reviewed by four blinded physicians. Observer errors were analyzed using nonparametric statistics (Friedman's test) to determine whether STR cohorts had detectably different displacement profiles. Post hoc bootstrap resampling was applied to evaluate potential generalizability. RESULTS: The observer-based trial revealed a statistically significant difference between cohort means for observer displacement vector error ([Formula: see text]) and for [Formula: see text]-axis [Formula: see text]. Bootstrap analysis suggests a 15% gain in isocenter translational setup error with reduction of STR from 3 mm to [Formula: see text]2 mm, though interobserver variance was a larger feature than STR-associated measurement variance. CONCLUSIONS: Higher resolution DRRs generated using finer CT scan STR resulted in improved observer performance at shift detection and could decrease operator-dependent geometric error. Ideally, CT STRs [Formula: see text]2 mm should be utilized for DRR generation in the head and neck.

Current modalities of accelerated partial breast irradiation.

The benefits of adjuvant whole-breast irradiation (WBI) after breast-conserving surgery are well established and WBI is a standard of care. In selected patients with early stage breast cancer, accelerated partial breast irradiation (APBI) has emerged as an alternative treatment option to WBI. Early trials of APBI have demonstrated an excellent local control rate and an associated good-to-excellent cosmetic outcome. APBI can reduce both the treatment volume and overall treatment time of adjuvant radiation therapy, which potentially overcomes logistical barriers associated with WBI that have previously prevented eligible women from pursuing breast-conserving therapy. Likewise, the addition of new modalities for APBI delivery has increased the number of patients who might be eligible for this adjuvant treatment-in the setting of breast-conserving surgery-despite the limited availability of long-term data on APBI outcomes compared to historical WBI outcomes. Ongoing phase III trials aim to compare APBI with WBI and also point the practitioner to the appropriate APBI patient selection criteria. Here, we review available modalities, patient selection criteria and consensus guideline recommendations, and current controversies in APBI.