Feasibility Study of Moderately Accelerated Intensity-Modulated Radiotherapy Plus Concurrent Weekly Cisplatin After Induction Chemotherapy in Locally Advanced Head-and Neck Cancer

Personalized automation of treatment planning in head-neck cancer: A step forward for quality in radiation therapy?

PURPOSE

To perform a comprehensive dosimetric and clinical evaluation of the new Pinnacle Personalized automated planning system for complex head-and-neck treatments.

METHODS

Fifteen consecutive head-neck patients were enrolled. Radiotherapy was prescribed using VMAT with simultaneous integrated boost strategy. Personalized planning integrates the Feasibility engine able to supply an "a priori" DVH prediction of the achievability of planning goals. Comparison between clinically accepted manually-generated (MP) and automated (AP) plans was performed using dose-volume histograms and a blinded clinical evaluation by two radiation oncologists. Planning time between MP and AP was compared. Dose accuracy was validated using the PTW Octavius-4D phantom together with the 1500 2D-array.

RESULTS

For similar targets coverage, AP plans reported less irradiation of healthy tissue, with significant dose reduction for spinal cord, brainstem and parotids. On average, the mean dose to parotids and maximal doses to spinal cord and brainstem were reduced by 13-15% (p < 0.001), 9% (p < 0.001) and 16% (p < 0.001), respectively. The integral dose was reduced by 16% (p < 0.001). The dose conformity for the three PTVs was significantly higher with AP plans (p < 0.001). The two oncologists chose AP plans in more than 80% of cases. Overall planning times were reduced to <30 min for automated optimization. All AP plans passed the 3%/2 mm γ-analysis by more than 95%.

CONCLUSION

Complex head-neck plans created using Personalized automated engine provided an overall increase of plan quality, in terms of dose conformity and sparing of normal tissues. The Feasibility module allowed OARs dose sparing well beyond the clinical objectives.

Meta-analysis of induction chemotherapy as a selection marker for chemoradiation in the head and neck

OBJECTIVE

Many trials incorporate induction chemotherapy (IC) in selecting for organ preservation in head and neck squamous cell carcinomas (HNSCC). However, few studies examine IC response in predicting for chemoradiation therapy (CRT) response. This meta-analysis aims to determine the predictive accuracy of IC for subsequent response to CRT and overall survival (OS).

DATA SOURCES

Medline, EMBASE, Cochrane register.

METHODS

A systematic search identified studies from database inception to October 2016 that used IC prior to CRT as definitive treatment for advanced HNSCC. The sensitivities and specificities of IC response predicting for complete CRT response were calculated, and the results were pooled in a summary receiver operating curve. One-, 2- and 5-year OS data were extracted.

RESULTS

Seven studies (n = 423 patients) were analyzed for response and six (n = 439) for OS. Pooled median sensitivity and specificity of IC response predicting CRT response were 0.95 (95% confidence interval [CI]: 0.72-0.98) and 0.43 (95% CI: 0.00-0.61), respectively. Patients were more likely to respond to CRT given previous response to IC (positive likelihood ratio = 1.6; 95% CI: 1.21-2.11) and less likely to respond to CRT if they failed to respond to IC (negative likelihood ratio = 0.16; 95% CI: 0.07-0.38). At 2 years, good response to IC was a statistically significant prognostic marker with a risk ratio of 1.35 (95% CI: 1.12-1.64).

CONCLUSION

Our data suggests that patients with poor IC response will have poorer response to CRT and should be directed to other modalities. In contrast, good IC response does not guarantee a favorable outcome to CRT; however, because these patients are likely to have better prognoses, they should be offered salvage therapies of curative intent despite treatment failure.

LEVEL OF EVIDENCE

NA. Laryngoscope, 128:1594-1601, 2018.

Early death among head and neck cancer patients

PURPOSE OF REVIEW

Management of advanced head and neck cancer (HNC) is characterized by high mortality. Furthermore, the treatment involves significant burden to patients and high costs to healthcare systems. Recognizing the risks of early death in patients with a high probability of noncurable disease is important for each individual treatment decision-making. It is thus critical to consider the benefits and side-effects of the planned treatment in relation to the expected survival and to discuss these factors with the patient. However, only few studies have documented early death in HNC patients, that is, during the first posttreatment 6 months. We performed a systematic literature review to find the incidence of this phenomenon and to outline the probable cause.

RECENT FINDINGS

Early mortality in patients with HNC can be explained either by direct effect of malignant disease, may be related to comorbidities, or secondary to the treatment. These factors act together resulting in expected or unexpected early death.

SUMMARY

The present review provides information on the mechanisms leading to early phase mortality (<6 months) after management of HNC. It also reports the incidence of this phenomenon among Finnish and Swedish patient populations.

Volumetric modulated arc therapy (VMAT) and simultaneous integrated boost in head-and-neck cancer: is there a place for critical swallowing structures dose sparing?

OBJECTIVE

To explore the potential of volumetric-modulated arc therapy (VMAT) to reduce the risk of swallowing problems after curative chemoradiotherapy.

METHODS

20 patients with head and neck cancer who previously underwent radiotherapy were selected. Radiotherapy was prescribed according to simultaneous integrated boost technique with all targets irradiated simultaneously over 30 daily fractions. Doses of 70.5 (67.5), 60.0 and 55.5 Gy were prescribed to primary tumour, high-risk nodal regions and low-risk nodal regions, respectively. Pharyngeal constrictor muscles (PCM) and glottic and supraglottic larynx (SGL) were considered organs at risk related to swallowing dysfunction (SW-OARs). Upper pharyngeal constrictor muscles (uPCM), middle pharyngeal constrictor muscles (mPCM) and lower pharyngeal constrictor muscles (lPCM) part of PCM were also outlined separately. Clinical standard plans (standard-VMAT) and plans aiming to spare SW-OARs (swallowing dysfunction-VMAT) were also created. Normal tissue complication probabilities (NTCP) for physician-rated swallowing dysfunction were calculated using a recently predictive model developed by Christianen et al.

RESULTS

Planning with two strategies demonstrated comparable planning target volume coverage and no differences in sparing of parotid glands and other non-swallowing organs at risk. SW-VMAT plans provided mean dose reduction for uPCM and SGL by 3.9 and 4.5 Gy, respectively. NTCP values for Radiation Therapy Oncology Group grade 2-4 swallowing dysfunction was decreased by 9.2%. Dose reductions with SW-VMAT depended on tumour location and overlap with SW-OARs.

CONCLUSION

VMAT plans aiming at sparing swallowing structures are feasible, providing a significant reduction in NTCP swallowing dysfunction with respect to conventional VMAT.

ADVANCES IN KNOWLEDGE

Dysphagia is today considered one of the dose-limiting toxicities of chemoradiotherapy. The dose sparing of swallowing structures represents a major challenge in radiotherapy. VMAT is a complex new technology having the potential to significantly reduce the risk of dysphagia after curative chemoradiotherapy.

Prolonged radiation time and low nadir hemoglobin during postoperative concurrent chemoradiotherapy are both poor prognostic factors with synergistic effect on locally advanced head and neck cancer patients

BACKGROUND

Anemia, a common complication of head and neck cancer treatment, is regarded as a poor prognostic factor. We evaluated the impact of low hemoglobin (Hb) levels, measured at different time points, on a consecutive cohort of patients with locally advanced squamous cell carcinoma of the head and neck (LA-SCCHN) who underwent postoperative concurrent chemoradiotherapy (CCRT).

MATERIALS AND METHODS

From 2002 to 2009, 140 patients were enrolled and reviewed retrospectively. Preoperative (pre-op Hb), pre-CCRT Hb, and nadir Hb during CCRT were measured and recorded. The three Hb parameters were analyzed against several well-established pathologic risk factors and radiation-associated variables. Prognostic impacts were investigated with multivariate analysis by Cox proportional hazards model.

RESULTS

On Cox regression analysis, significantly higher risk of death was associated with pre-op Hb ≦13 g/dL (hazard ratio [HR] =1.8; 95% confidence interval [CI], 1.1-3.1; P=0.023), nadir Hb ≦11 g/dL (HR =1.9; 95% CI, 1.1-3.3; P=0.020), radiation treatment time (RTT) >7 weeks (HR =1.9; 95% CI, 1.1-3.3; P=0.022), and multiple positive lymph nodes (HR =2.1; 95% CI, 1.2-3.7; P=0.010), after adjusting for primary tumor site and pathologic lymphovascular invasion. Patients with poor prognosticators including low nadir Hb ≦11 g/dL and RTT >7 weeks had a higher risk of death (HR =4.0; 95% CI =1.6-10.2; P=0.004).

CONCLUSION

In the treatment setting of LA-SCCHN patients who underwent postoperative CCRT, coexistance of lower nadir Hb during CCRT and prolonged RTT resulted in reduced survival.

Technical guidelines for head and neck cancer IMRT on behalf of the Italian association of radiation oncology - head and neck working group

Performing intensity-modulated radiotherapy (IMRT) on head and neck cancer patients (HNCPs) requires robust training and experience. Thus, in 2011, the Head and Neck Cancer Working Group (HNCWG) of the Italian Association of Radiation Oncology (AIRO) organized a study group with the aim to run a literature review to outline clinical practice recommendations, to suggest technical solutions and to advise target volumes and doses selection for head and neck cancer IMRT. The main purpose was therefore to standardize the technical approach of radiation oncologists in this context. The following paper describes the results of this working group. Volumes, techniques/strategies and dosage were summarized for each head-and-neck site and subsite according to international guidelines or after reaching a consensus in case of weak literature evidence.

Assessing the feasibility of volumetric-modulated arc therapy using simultaneous integrated boost (SIB-VMAT): An analysis for complex head-neck, high-risk prostate and rectal cancer cases

Intensity-modulated radiotherapy (IMRT) allowed the simultaneous delivery of different doses to different target volumes within a single fraction, an approach called simultaneous integrated boost (SIB). As consequence, the fraction dose to the boost volume can be increased while keeping low doses to the elective volumes, and the number of fractions and overall treatment time will be reduced, translating into better radiobiological effectiveness. In recent years, volumetric-modulated arc therapy (VMAT) has been shown to provide similar plan quality with respect to fixed-field IMRT but with large reduction in treatment time and monitor units (MUs) number. However, the feasibility of VMAT when used with SIB strategy has few investigations to date. We explored the potential of VMAT in a SIB strategy for complex cancer sites. A total of 15 patients were selected, including 5 head-and-neck, 5 high-risk prostate, and 5 rectal cancer cases. Both a double-arc VMAT and a 7-field IMRT plan were generated for each case using Oncentra MasterPlan treatment planning system for an Elekta Precise linac. Dosimetric indexes for targets and organs at risk (OARs) were compared based on dose-volume histograms. Conformity index, homogeneity index, and dose-contrast index were used for target analyses. The equivalent uniform doses and the normal tissue complication probabilities were calculated for main OARs. MUs number and treatment time were analyzed to score treatment efficiency. Pretreatment dosimetry was performed using 2-dimensional (2D)-array dosimeter. SIB-VMAT plans showed a high level of fluence modulation needed for SIB treatments, high conformal dose distribution, similar target coverage, and a tendency to improve OARs sparing compared with the benchmark SIB-IMRT plans. The median treatment times reduced from 13 to 20 minutes to approximately 5 minutes for all cases with SIB-VMAT, with a MUs reduction up to 22.5%. The 2D-array ion-chambers' measurements reported an agreement of more than 95% for a criterion of 3% to 3mm. SIB-VMAT was able to combine the advantages of conventional SIB-IMRT with its highly conformal dose distribution and OARs sparing and the advantages of 3D-conformal radiotherapy with its fast delivery.

Oncolytic measles virus encoding thyroidal sodium iodide symporter for squamous cell cancer of the head and neck radiovirotherapy

Oncolytic measles virus (MV) encoding the human thyroidal sodium iodide symporter (MV-NIS) has proved to be safe after intraperitoneal or intravenous administration in patients with ovarian cancer or multiple myeloma, respectively, but it has not yet been administered through intratumoral injection in humans. Squamous cell carcinoma (SCC) of the head and neck (SCCHN) usually is locally invasive and spreads to the cervical lymph nodes, which are suitable for the intratumoral administration of oncolytic viruses. To test whether oncolytic MV is an effective treatment for SCCHN, we used oncolytic MV-NIS to infect SCCHN in vitro and in vivo. The data show that SCCHN cells were infected and killed by MV-NIS in vitro. Permissiveness of the tumor cells to MV infection was not affected by irradiation after viral addition. Monitored noninvasively through radioiodine-based single-photon emission computed tomography/computed tomography, intratumorally virus-delivered NIS has concentrated the radioiodine in the MV-NIS-treated tumors in the FaDu mouse xenograft model of human SCCHN, and the antitumor effect could be boosted significantly (p<0.05) either with concomitant cyclophosphamide therapy or with appropriately timed administration of radioiodine (131)I. MV-NIS could be a promising new anticancer agent that may substantially enhance the outcomes of standard therapy after intratumoral administration in patients with locally advanced SCCHN.