Haruo Inokuchi

Treatment outcomes of definitive chemoradiotherapy for patients with hypopharyngeal cancer

We analyzed the efficacy of definitive chemoradiotherapy (CRT) for patients with hypopharyngeal cancer (HPC). Subjects comprised 97 patients who were treated with definitive CRT from 1990 to 2006. Sixty-one patients (62.9%) with resectable disease who aimed to preserve the larynx received induction chemotherapy (ICT), whereas 36 patients (37.1%) with resectable disease who refused an operation or who had unresectable disease received primary alternating CRT or concurrent CRT (non-ICT). The median dose to the primary lesion was 66 Gy. The median follow-up time was 77 months. The 5-year rates of overall survival (OS), progression-free survival (PFS), local control (LC), and laryngeal preservation were 68.7%, 57.5%, 79.1%, and 70.3%, respectively. The T-stage was a significant prognostic factor in terms of OS, PFS and LC in both univariate and multivariate analyses. The 5-year rates of PFS were 45.4% for the ICT group and 81.9% for the non-ICT group. The difference between these groups was significant with univariate analysis (P = 0.006). Acute toxicity of Grade 3 to 4 was observed in 34 patients (35.1%). Grade 3 dysphagia occurred in 20 patients (20.6%). Twenty-nine (29.8%) of 44 patients with second primary cancer had esophageal cancer. Seventeen of 29 patients had manageable superficial esophageal cancer. The clinical efficacy of definitive CRT for HPC is thought to be promising in terms of not only organ preservation but also disease control. Second primary cancer may have a clinical impact on the outcome for HPC patients, and special care should be taken when screening at follow-up.

Dosimetric evaluation of the Acuros XB algorithm for a 4 MV photon beam in head and neck intensity-modulated radiation therapy.

In this study, we assessed the differences in the dose distribution of a 4 MV photon beam among different calculation algorithms: the Acuros XB (AXB) algorithm, the analytic anisotropic algorithm (AAA), and the pencil beam convolution (PBC) algorithm (ver. 11.0.31), in phantoms and in clinical intensity-modulated radiation therapy (IMRT) plans. Homogeneous and heterogeneous, including middle-, low-, and high-density, phantoms were combined to assess the percentage depth dose and lateral dose profiles among AXB, AAA, and PBC. For the phantom containing the low-density area, AXB was in agreement with measurement within 0.5%, while the greatest differences between the AAA and PBC calculations and measurement were 2.7% and 3.6%, respectively. AXB showed agreement with measurement within 2.5% at the high-density area, while AAA and PBC overestimated the dose by more than 4.5% and 4.0%, respectively. Furthermore, 15 IMRT plans, calculated using AXB, for oropharyngeal, hypopharyngeal, and laryngeal carcinomas were analyzed. The dose prescription was 70 Gy to 50% of the planning target volume (PVT70). Subsequently, each plan was recalculated using AAA and PBC while maintaining the AXB-calculated monitor units, leaf motion, and beam arrangement. Additionally, nine hypopharyngeal and laryngeal cancer patients were analyzed in terms of PTV70 for cartilaginous structures (PVT70_cartilage). The doses covering 50% to PTV70 calculated by AAA and PBC were 2.1%±1.0% and 3.7%±0.8% significantly higher than those using AXB, respectively (p<0.01). The increases in doses to PTV70_cartilage calculated by AAA and PBC relative to AXB were 3.9% and 5.3% on average, respectively, and were relatively greater than those in the entire PVT70. AXB was found to be in better agreement with measurement in phantoms in heterogeneous areas for the 4 MV photon beam. Considering AXB as the standard, AAA and PBC overestimated the IMRT dose for head and neck cancer. The dosimetric differences should not be ignored, particularly with cartilaginous structures in PTV. PACS number: 87.55.-x, 87.55.dk, 87.55.kd.In this study, we assessed the differences in the dose distribution of a 4 MV photon beam among different calculation algorithms: the Acuros XB (AXB) algorithm, the analytic anisotropic algorithm (AAA), and the pencil beam convolution (PBC) algorithm (ver. 11.0.31), in phantoms and in clinical intensity‐modulated radiation therapy (IMRT) plans. Homogeneous and heterogeneous, including middle‐, low‐, and high‐density, phantoms were combined to assess the percentage depth dose and lateral dose profiles among AXB, AAA, and PBC. For the phantom containing the low‐density area, AXB was in agreement with measurement within 0.5%, while the greatest differences between the AAA and PBC calculations and measurement were 2.7% and 3.6%, respectively. AXB showed agreement with measurement within 2.5% at the high‐density area, while AAA and PBC overestimated the dose by more than 4.5% and 4.0%, respectively. Furthermore, 15 IMRT plans, calculated using AXB, for oropharyngeal, hypopharyngeal, and laryngeal carcinomas were analyzed. The dose prescription was 70 Gy to 50% of the planning target volume (PVT70). Subsequently, each plan was recalculated using AAA and PBC while maintaining the AXB‐calculated monitor units, leaf motion, and beam arrangement. Additionally, nine hypopharyngeal and laryngeal cancer patients were analyzed in terms of PTV70 for cartilaginous structures (PVT70_cartilage). The doses covering 50% to PTV70 calculated by AAA and PBC were 2.1%±1.0% and 3.7%±0.8% significantly higher than those using AXB, respectively (p<0.01). The increases in doses to PTV70_cartilage calculated by AAA and PBC relative to AXB were 3.9% and 5.3% on average, respectively, and were relatively greater than those in the entire PVT70. AXB was found to be in better agreement with measurement in phantoms in heterogeneous areas for the 4 MV photon beam. Considering AXB as the standard, AAA and PBC overestimated the IMRT dose for head and neck cancer. The dosimetric differences should not be ignored, particularly with cartilaginous structures in PTV. PACS number: 87.55.‐x, 87.55.dk, 87.55.kd

Recurrence patterns after postoperative radiotherapy for squamous cell carcinoma of the pharynx and larynx

Abstract Conclusions: Distant metastasis was a major pattern of recurrence after postoperative radiotherapy (PORT) for squamous cell carcinoma (SCC) of the oropharynx, hypopharynx, and larynx. PORT provided good loco-regional control, with tolerable toxicities. Advanced pT and pN were unfavorable prognostic factors. Objective: To determine the clinical outcomes, and the patterns and risk factors for recurrence of SCCs of the oropharynx, hypopharynx, and larynx treated with surgery and PORT. Methods: We retrospectively reviewed 84 patients who received PORT after definitive surgery for SCC of the oropharynx, hypopharynx, or larynx between 2000 and 2010. The primary sites were the oropharynx in 25 patients, hypopharynx in 47 patients, and larynx in 12 patients. Results: The 3-year overall survival (OS), progression-free survival (PFS), and loco-regional control (LRC) rates were 64.9%, 56.7%, and 92.1%, respectively. Recurrences were observed in 27 patients: 6 patients had loco-regional recurrence and 23 patients developed distant metastasis. On multivariate analysis, pT4 and pN2c-N3 displayed significantly worse effects on OS (p = 0.02 and p < 0.01, respectively) and PFS (p = 0.02 and p < 0.001, respectively). In the acute phase, 12 patients experienced grade 3 or 4 toxicities. There were no grade 5 toxicities. Late grade 3 toxicity developed in six patients and no grade 4 or 5 toxicities were observed.

A pilot study of highly hypofractionated intensity-modulated radiation therapy over 3 weeks for localized prostate cancer

Abstract The purpose of this pilot study was to evaluate the feasibility of highly hypofractionated intensity-modulated radiation therapy (IMRT) in 15 fractions over 3 weeks for treating localized prostate cancer based on prostate position-based image-guided radiation therapy. Twenty-five patients with National Comprehensive Cancer Network (NCCN) very low- to unfavorable intermediate-risk prostate cancer were enrolled in this study from April 2014 to September 2015 to receive highly hypofractionated IMRT (without intraprostatic fiducial markers) delivering 54 Gy in 15 fractions over 3 weeks. Patients with intermediate-risk disease underwent neoadjuvant androgen suppression for 4–8 months. Twenty-four patients were treated with highly hypofractionated IMRT, and one was treated with conventionally fractionated IMRT because the dose constraint of the small bowel seemed difficult to achieve during the simulation. Seventeen percent had very low- or low-risk, 42% had favorable intermediate-risk, and 42% had unfavorable intermediate-risk disease according to NCCN guidelines. The median follow-up period was 31 months (range, 24–42 months). No Grade ≥3 acute toxicity was observed, and the incidence rates of Grade 2 acute genitourinary and gastrointestinal toxicities were 21% and 4%, respectively. No Grade ≥2 late toxicity was observed. Biochemical relapse was observed in one patient at 15 months, and the biochemical relapse-free survival rate was 95.8% at 2 years. A prostate-specific antigen bounce of ≥0.4 ng/ml was observed in 11 patients (46%). The highly hypofractionated IMRT regimen is feasible in patients with localized prostate cancer and is more convenient than conventionally fractionated schedules for patients and health-care providers.

Correlation between urinary dose and delayed radiation cystitis after 78 Gy intensity-modulated radiotherapy for high-risk prostate cancer: A 10-year follow-up study of genitourinary toxicity in clinical practice

Highlights • High-dose prostate IMRT was well tolerated in terms of long-term GU toxicities.• Hematuria was the most common long-term GU toxicity after high-dose IMRT.• Bladder neck dose–volume data were significantly associated with hematuria.

Recovery of Serum Testosterone Levels and Sexual Function in Patients Treated With Short-term Luteinizing Hormone-releasing Hormone Antagonist as a Neoadjuvant Therapy Before External Radiotherapy for Intermediate-risk Prostate Cancer: Preliminary Prospective Study

Introduction External beam radiation therapy (EBRT) with short‐term androgen deprivation therapy is the standard of care for intermediate‐risk prostate cancer patients. However, no study to date has evaluated the hormonal kinetics or sexual and hormonal function recovery after cessation of short‐term luteinizing hormone (LH)‐releasing hormone (LHRH) antagonist treatment. Patients and Methods Ten intermediate‐risk prostate cancer patients (mean age, 69.9 years) were included. All patients received 4 months of LHRH antagonist (degarelix) treatment followed by EBRT. The testosterone, luteinizing hormone (LH), follicle‐stimulating hormone, and prostate‐specific antigen levels were measured and Expanded Prostate Cancer Index Composite questionnaires were completed before LHRH antagonist therapy at baseline; 1, 2, 3, and 4 months after the first injection of LHRH antagonist treatment; and every 2 months thereafter until 18 months. Results The testosterone levels were at the castration level at 1 month after the first LHRH antagonist injection. The median interval to recover a normal testosterone level (> 7.2 nmol/L) was 7 months after the last LHRH antagonist administration. The LH and follicle‐stimulating hormone levels decreased but had increased more than twice above baseline at 15 months after the last LHRH antagonist injection. The sexual function and hormonal bother subdomain scores and sexual and hormonal domain scores decreased once after LHRH antagonist treatment but had significantly recovered thereafter (P < .05). Conclusion In most patients, the testosterone level had normalized within 9 months after the last LHRH administration. Sexual and hormonal function recovered after short‐term LHRH antagonist administration for neoadjuvant therapy before EBRT. Micro‐Abstract No investigation has examined the recovery of serum testosterone or sexual and hormonal function after cessation of luteinizing hormone‐releasing hormone (LHRH) antagonist administration for intermediate‐risk prostate cancer patients before external radiotherapy. The results of the present preliminary prospective study have shown that the serum testosterone level normalized within 9 months after the last LHRH antagonist treatment with gradual recovery of sexual and hormonal function.