Whole brain radiotherapy with adjuvant or concomitant boost in brain metastasis: dosimetric comparison between helical and volumetric IMRT technique.

BACKGROUND: To compare and evaluate the possible advantages related to the use of VMAT and helical IMRT and two different modalities of boost delivering, adjuvant stereotactic boost (SRS) or simultaneous integrated boost (SIB), in the treatment of brain metastasis (BM) in RPA classes I-II patients. METHODS: Ten patients were treated with helical IMRT, 5 of them with SRS after whole brain radiotherapy (WBRT) and 5 with SIB. MRI co-registration with planning CT was mandatory and prescribed doses were 30 Gy in 10 fractions (fr) for WBRT and 15Gy/1fr or 45Gy/10fr in SRS or SIB, respectively. For each patient, 4 "treatment plans" (VMAT SRS and SIB, helical IMRT SRS and SIB) were calculated and accepted if PTV boost was included in 95 % isodose and dose constraints of the main organs at risk were respected without major deviations. Homogeneity Index (HI), Conformal Index (CI) and Conformal Number (CN) were considered to compare the different plans. Moreover, time of treatment delivery was calculated and considered in the analysis. RESULTS: Volume of brain metastasis ranged between 1.43 and 51.01 cc (mean 12.89 ± 6.37 ml) and 3 patients had double lesions. V95% resulted over 95 % in the average for each kind of technique, but the "target coverage" was inadequate for VMAT planning with two sites. The HI resulted close to the ideal value of zero in all cases; VMAT-SIB, VMAT-SRS, Helical IMRT-SIB and Helical IMRT-SRS showed mean CI of 2.15, 2.10, 2.44 and 1.66, respectively (optimal range: 1.5-2.0). Helical IMRT-SRS was related to the best and reliable finding of CN (0.66). The mean of treatment time was 210 s, 467 s, 440 s, 1598 s, respectively, for VMAT-SIB, VMAT-SRS, Helical IMRT-SIB and Helical IMRT-SRS. CONCLUSIONS: This dosimetric comparison show that helical IMRT obtain better target coverage and respect of CI and CN; VMAT could be acceptable in solitary metastasis. SIB modality can be considered as a good choice for clinical and logistic compliance; literature's preliminary data are confirming also a radiobiological benefit for SIB. Helical IMRT-SRS seems less effective for the long time of treatment compared to other techniques.

Clinical outcomes and toxicity after exclusive versus postoperative radiotherapy in supraglottic cancer: new solutions for old problems? The case of stage III and IV disease.

PURPOSE: To compare toxicity, survival and laryngeal preservation rate after radiotherapy alone (RR), radiotherapy after supraglottic horizontal laryngectomy (SHLR) and radiotherapy after total laryngectomy (TLR) for advanced supraglottic laryngeal cancer. MATERIALS AND METHODS: From 1984 to 2012, 532 patients (pts) were treated in our Department: 273 were potentially fit for conservative surgery (Group I) and 259 were not amenable to partial surgery (Group II). RESULTS: A younger age (p = 0.005), a better performance status (p < 0.001), the absence of comorbidities (p < 0.001) and the absence of nodal involvement (p = 0.006) favorably impacted on overall survival. More high-grade mucositis (p = 0.009), mild dysphagia (p < 0.001) and mild xerostomia (p < 0.001) were found in RR group; surgical patients had more edema of neck (p = 0.009) and skin toxicity (p = 0.008). Group I No differences in local, nodal and distant recurrences and in number of rescue laryngectomies were observed. The disease characteristics (T, N and stage) but not the treatment modality impacted on disease-free survival (DFS). Group II There was an higher number of local (p = 0.013) and nodal (p = 0.022) recurrences after RR. DFS (p = 0.01) was longer after TLR. No differences in DFS between TLR patients and RR patients who underwent radio-chemotherapy were found. CONCLUSION: In Group I, RR results in a local-regional control and organ preservation comparable to surgical treatments, with only slight increase of late mild xerostomia and dysphagia. In Group II RR was less effective than TLR, with a significantly worse DFS. The use of concurrent radical radio-chemotherapy seems to provide comparable loco-regional control to TLR.

Clinical outcomes and toxicity after exclusive versus postoperative radiotherapy in supraglottic cancer: new solutions for old problems? The case of stage I and II disease.

PURPOSE: To compare acute and late toxicities, survival, and laryngeal preservation after radiotherapy alone (RR) or radiotherapy after partial laryngectomy (PLR) in early supraglottic laryngeal cancer. MATERIALS AND METHODS: From 1984 to 2012, 172 patients were treated in our department. We analyzed and compared toxicities (CTCAE v 4.0), overall survival (OS), disease-specific survival (DSS), disease-free survival (DFS), local relapse-free survival (LRFS), nodal relapse-free survival (NRFS), metastasis-free survival (MFS), and the number of salvage total laryngectomies. RESULTS: Patients in the RR group were older (p = 0.05) and had more often comorbidities (p = 0.025); those in the PLR group had mostly T2 disease (p = 0.014). No difference in number of local, nodal, and distant recurrences was found. A higher incidence of late mild dry mouth in patients treated with RR (38 vs. 4 %, p = 0.000) was reported. At univariate analysis, only a younger age, a better performance status, and the absence of comorbidities favorably impacted on OS and DSS. No differences were found in DFS, LRFS, NRFS, MFS, and the number of rescue laryngectomies between the two groups. Younger age and a good performance status persisted as a predictive factor of better survival (OS and DSS) at multivariate analysis. CONCLUSION: Radical radiotherapy appears to be a viable alternative to conservative surgery, even in elderly patients with poor performance status and comorbidities. Salvage laryngectomy in the RR group was compared favorably with those reported in other conservative surgery series and in the group treated postoperatively of our series.