Potential efficacy of local therapy for progressive lesions after nivolumab in patients with recurrent or metastatic squamous cell carcinoma of the head and neck.

BACKGROUND: In recurrent or metastatic squamous cell carcinoma of the head and neck (R/M SCCHN), local therapy (LT) such as surgery or radiotherapy can be treatment options for improved survival or quality of life. To date, however, few reports have addressed the efficacy of LT for sites of disease progression after immune checkpoint inhibitors, including other cancers. METHODS: We conducted a retrospective analysis of patients with R/M SCCHN originating from the oral cavity, oropharynx, hypopharynx, and larynx and treated with nivolumab. We extracted patients undergoing salvage LT or palliative radiotherapy (RT) to the selected progressive lesion at any time after initiation of nivolumab. RESULTS: Twenty-four patients received LT. Salvage LT was performed in 9 (37.5%) patients, including surgery and definitive RT in 5 and 4 patients, respectively. Palliative RT was performed in 15 (62.5%) patients. LT was provided in 10 (41.7%) patients for oligoprogressive disease. Twelve (50.0%) patients received subsequent systemic therapy immediately after LT. Classification based on patient treatment divided the population into four subgroups with different prognoses (salvage LT followed by subsequent systemic therapy [n = 3], salvage LT alone [n = 6], palliative RT followed by subsequent systemic therapy [n = 9], and palliative RT alone [n = 6]). Median OS in this order was 24.5, 9.0, 7.3, and 2.4 months (p = 0.001). All patients in the salvage LT followed by subsequent systemic therapy group continued nivolumab. CONCLUSION: In R/M SCCHN patients who have received nivolumab, salvage LT for the selected progressive lesion with continuation of nivolumab potentially provides an excellent survival prognosis.

Relationship between changes in quality of life and genitourinary toxicity grade after brachytherapy with I-125 alone for localised prostate cancer.

Background: The relationship between the grading of toxicities based on toxicity criteria and longitudinal changes in quality of life (QOL) scores after permanent prostate brachytherapy (PPB) for localized prostate cancer remains unclear. This study aimed to evaluate these relationships. Materials and methods: We assessed 107 patients treated with PPB using Iodine-125 alone from May 2007 to April 2010. Disease-specific QOL scores before PPB and at 1, 3, 6, 12, and 24 months after PPB were retrospectively evaluated with the Expanded Prostate Cancer Index Composite (EPIC), focusing on urinary domains. Toxicities were graded using the Radiation therapy oncology group and the European organization for research and treatment of cancer toxicity criteria. Results: The median follow-up duration was 116 (range 18-148) months. Thirty-four patients (31.8%) developed grade ≥ 2 acute genitourinary (GU) toxicities; six (5.6%) developed grade ≥ 2 late GU toxicities. The general urinary domain score dropped significantly at 1 month (77.1 ± 14.1) post-PPB compared to the baseline score (92.2 ± 8.2), and then gradually returned to the baseline level by 12 months (93.7 ± 8.3) post-PPB. Reductions in the general urinary domain scores, including its subscale scores at 1, 3, and 6-months post-PPB were significantly greater among patients with grade ≥ 2 GU toxicity than among those with grade 0-1 GU toxicity. Changes in urinary domain scores demonstrated a close relationship with acute GU toxicity grades after PPB. Conclusions: Longitudinal assessments of the EPIC QOL scores provided additional information regarding time-course changes in GU toxicities after PPB.

The rice wound-inducible transcription factor RERJ1 sharing same signal transduction pathway with OsMYC2 is necessary for defense response to herbivory and bacterial blight.

KEY MESSAGE: This study describes biological functions of the bHLH transcription factor RERJ1 involved in the jasmonate response and the related defense-associated metabolic pathways in rice, with particular focus on deciphering the regulatory mechanisms underlying stress-induced volatile emission and herbivory resistance. RERJ1 is rapidly and drastically induced by wounding and jasmonate treatment but its biological function remains unknown as yet. Here we provide evidence of the biological function of RERJ1 in plant defense, specifically in response to herbivory and pathogen attack, and offer insights into the RERJ1-mediated regulation of metabolic pathways of specialized defense compounds, such as monoterpene linalool, in possible collaboration with OsMYC2-a well-known master regulator in jasmonate signaling. In rice (Oryza sativa L.), the basic helix-loop-helix (bHLH) family transcription factor RERJ1 is induced under environmental stresses, such as wounding and drought, which are closely linked to jasmonate (JA) accumulation. Here, we investigated the biological function of RERJ1 in response to biotic stresses, such as herbivory and pathogen infection, using an RERJ1-defective mutant. Transcriptome analysis of the rerj1-Tos17 mutant revealed that RERJ1 regulated the expression of a typical family of conserved JA-responsive genes (e.g., terpene synthases, proteinase inhibitors, and jasmonate ZIM domain proteins). Upon exposure to armyworm attack, the rerj1-Tos17 mutant exhibited more severe damage than the wildtype, and significant weight gain of the larvae fed on the mutant was observed. Upon Xanthomonas oryzae infection, the rerj1-Tos17 mutant developed more severe symptoms than the wildtype. Among RERJ1-regulated terpene synthases, linalool synthase expression was markedly disrupted and linalool emission after wounding was significantly decreased in the rerj1-Tos17 mutant. RERJ1 appears to interact with OsMYC2-a master regulator of JA signaling-and many OsJAZ proteins, although no obvious epistatic interaction was detected between them at the transcriptional level. These results indicate that RERJ1 is involved in the transcriptional induction of JA-mediated stress-responsive genes via physical association with OsMYC2 and mediates defense against herbivory and bacterial infection through JA signaling.

Impacts of the STING-IFNAR1-STAT1-IRF1 pathway on the cellular immune reaction induced by fractionated irradiation.

Radiotherapy (RT) combined with immune checkpoint inhibitors has recently produced outstanding results and is expected to be adaptable for various cancers. However, the precise molecular mechanism by which immune reactions are induced by fractionated RT is still controversial. We aimed to investigate the mechanism of the immune response regarding multifractionated, long-term radiation, which is most often combined with immunotherapy. Two human esophageal cancer cell lines, KYSE-450 and OE-21, were irradiated by fractionated irradiation (FIR) daily at a dose of 3 Gy in 5 d/wk for 2 weeks. Western blot analysis and RNA sequencing identified type I interferon (IFN) and the stimulator of IFN genes (STING) pathway as candidates that regulate immune response by FIR. We inhibited STING, IFNAR1, STAT1, and IFN regulatory factor 1 (IRF1) and investigated the effects on the immune response in cancer cells and the invasion of surrounding immune cells. We herein revealed type I IFN-dependent immune reactions and the positive feedback of STING, IRF1, and phosphorylated STAT1 induced by FIR. Knocking out STING, IFNAR1, STAT1, and IRF1 resulted in a poorer immunological response than that in WT cells. The STING-KO KYSE-450 cell line showed significantly less invasion of PBMCs than the WT cell line under FIR. In the analysis of STING-KO cells and migrated PBMCs, we confirmed the occurrence of STING-dependent immune activation under FIR. In conclusion, we identified that the STING-IFNAR1-STAT1-IRF1 axis regulates immune reactions in cancer cells triggered by FIR and that the STING pathway also contributes to immune cell invasion of cancer cells.

Comprehensive screening for drugs that modify radiation-induced immune responses.

BACKGROUND: Combination therapy based on radiotherapy and immune checkpoint inhibitors (ICIs) was recently reported as effective for various cancers. The radiation-induced immune response (RIIR) is an essential feature in ICI-combined radiotherapy; however, the effects of drugs used concomitantly with RIIR remain unclear. We screened for drugs that can modify RIIR to understand the mutual relationship between radiotherapy and combined drugs in ICI-combined radiotherapy. METHODS: We established a high-throughput system with reporter gene assays for evaluating RIIR, focusing on factors acting downstream of the STING-IRF pathway, which can stimulate cancer cells, T cells, and dendritic cells. We further quantified the effects of 2595 drugs, including those approved by the Food and Drug Administration, on RIIR in vitro. RESULTS: The reporter assay results correlated well with the expression of immune response proteins such as programmed death-ligand 1. This high-throughput system enabled the identification of drugs including cytotoxic agents, molecular-targeted agents, and other agents that activate or suppress RIIR. CONCLUSIONS: Our study provides an encyclopedic catalogue of clinically approved drugs based on their effect on RIIR. In ICIs combined radiotherapy, activation of STING-IFN may improve the therapeutic effect and our result could form a biological basis for further clinical trials combining radiotherapy with ICIs.

Systemic therapy for salivary gland malignancy: current status and future perspectives.

Salivary gland malignancies are rare neoplasms that have a broad histological spectrum and a variety of biologic behaviors. Salivary gland malignancies are known as chemo-resistant tumors, which render optimal treatment challenging. This review summarizes the role of systemic therapy for salivary gland malignancies. To date, the advantage of adding concurrent chemotherapy has remained undefined for both postoperative and inoperable locally advanced salivary gland malignancy patients undergoing radiotherapy. For recurrent/metastatic disease, local and/or systemic treatment options should be discussed in a multidisciplinary setting with consideration to both patient needs and tumor factors. For symptomatic patients or those who may compromise organ function, palliative systemic therapy can be a reasonable option based on the results of phase II studies. Platinum combination regimens as first-line therapy have been widely accepted. Personalized therapies have become established options, particularly for androgen receptor-positive, HER2-positive and NTRK fusion-positive salivary gland malignancies (i.e. androgen receptor and HER2 in salivary duct carcinoma and NTRK3 in secretory carcinoma). For patients with adenoid cystic carcinoma, multi-targeted tyrosine kinase inhibitors have also been developed. Anti-PD1 checkpoint inhibitors have shown limited activity to date. Investigation of active systemic treatments for salivary gland malignancy remains a significant unmet need. Future directions might include a more comprehensive genomic screening approach (usually next-generation sequencing-based) and combination strategies using immune checkpoint inhibitors. These are rare malignancies that require ongoing effort in the conduct of high-quality clinical trials.

Human papillomavirus-related oropharyngeal carcinoma.

It was not until around 2000 that human papillomavirus-related oropharyngeal carcinoma was recognized as carcinoma with clinical presentations different from nonrelated head and neck carcinoma. Twenty years after and with the revision of the tumor-node-metastasis classification in 2017, various clinical trials focused on human papillomavirus-related oropharyngeal carcinoma to improve the prognosis and quality of life of patients with this disease. However, the incidence of human papillomavirus-related cancers is increasing, which is expected to be particularly prominent in Japan, where human papillomavirus vaccination is not widely available. In this review, we describe the current status of clinical trials (mainly focused on initial surgery and radiation dose reduction) for, primary and secondary prevention of, and the present status of human papillomavirus-related oropharyngeal carcinoma in Japan.

Comparative analysis of the immune responses in cancer cells irradiated with X-ray, proton and carbon-ion beams.

Radiotherapy (RT) is an effective treatment option for cancer; however, its efficacy remains less than optimal in locally advanced cancer. Immune checkpoint inhibitor-based therapy, including the administration of anti-PD-L1 antibodies, is a promising approach that works synergistically with RT. Proton beam therapy and carbon-ion therapy are common options for patients with cancer. Proton and carbon ions are reported to induce an immune reaction in cancer cells; however, the underlying mechanisms remain unclear. Here, we aimed to compare the immune responses after irradiation (IR) with X-ray, protons, and carbon ions in an oesophageal cancer cell line and the underlying mechanisms. An oesophageal cancer cell line, KYSE450, was irradiated with 1 fraction/15 GyE (Gy equivalent) of X-ray, proton, or carbon-ion beams, and then, the cells were harvested for RNA sequencing and gene enrichment analysis. We also knocked out STING and STAT1 in the quest for mechanistic insights. RNA sequencing data revealed that gene expression signatures and biological processes were different in KYSE450 irradiated with X-ray, proton, and carbon-ion beams 6-24 h after IR. However, after 3 days, a common gene expression signature was detected, associated with biological pathways involved in innate immune responses. Gene knock-out experiments revealed that the STING-STAT1 axis underlies the immune reactions after IR. X-Ray, proton, and carbon-ion IRs induced similar immune responses, regulated by the STING-STAT1 axis.

Induction chemotherapy in locally advanced squamous cell carcinoma of the head and neck.

In order to maximize the benefit of induction chemotherapy, practice based on a comprehensive interpretation of a large number of clinical trials, as in this review, is essential. The standard treatment for locally advanced squamous cell carcinoma of the head and neck is surgery or chemoradiation. However, induction chemotherapy followed by (chemo) radiotherapy may be used in some circumstances. Although many clinical trials of induction chemotherapy have been conducted, a rationale other than to preserve the larynx is still controversial. Selection of this modality should therefore be made with care. The current standard regimen for induction chemotherapy is docetaxel, cisplatin and 5-FU, but concerns remain about toxicity, cost and the duration of treatment. Regarding treatment after induction chemotherapy, it is also unclear whether radiation alone or chemoradiation is the better option. Furthermore, there is no answer as to what drugs should be used in combination with radiation therapy after induction chemotherapy. Several new induction chemotherapy treatment developments are currently underway, and future developments are expected. This review article summarizes the current position of induction chemotherapy for head and neck squamous cell carcinoma, based on the evidence produced to date, and discusses the future prospects for this treatment.

Immunotherapy for squamous cell carcinoma of the head and neck.

Squamous cell carcinoma of the head and neck is characterized by an immunosuppressive environment and evades immune responses through multiple resistance mechanisms. A breakthrough in cancer immunotherapy employing immune checkpoint inhibitors has evolved into a number of clinical trials with antibodies against programmed cell death 1 (PD-1), its ligand PD-L1 and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) for patients with squamous cell carcinoma of the head and neck. CheckMate141 and KEYNOTE-048 were practice-changing randomized phase 3 trials for patients with platinum-refractory and platinum-sensitive recurrent or metastatic squamous cell carcinoma of the head and neck, respectively. Furthermore, many combination therapies using anti-CTLA-4 inhibitors, tyrosine kinase inhibitors and immune accelerators are currently under investigation. Thus, the treatment strategy of recurrent or metastatic squamous cell carcinoma of the head and neck is becoming more heterogeneous and complicated in the new era of individualized medicine. Ongoing trials are investigating immunotherapeutic approaches in the curative setting for locoregionally advanced disease. This review article summarizes knowledge of the role of the immune system in the development and progression of squamous cell carcinoma of the head and neck, and provides a comprehensive overview on the development of immunotherapeutic approaches in both recurrent/metastatic and locoregionally advanced diseases.

Therapeutic results of proton beam therapy with concurrent chemotherapy for cT1 esophageal cancer and salvage endoscopic therapy for local recurrence.

BACKGROUND: Proton beam therapy (PBT) with concurrent chemotherapy is promising for esophageal squamous cell carcinoma (ESCC). The aim of study was to evaluate the outcome of concurrent chemo-proton therapy (CCPT), i.e., PBT with concurrent chemotherapy for cT1 ESCC and the salvage endoscopic therapy for local recurrence. METHODS: Patients with clinical T1 ESCC who underwent CCPT (60 GyE) between April 2013 and April 2017 at the National Cancer Center Hospital East were investigated. The efficacy of CCPT at the primary site was evaluated via endoscopy; primary complete response (CR) was defined as disappearance of the tumor lesion/ulcer and absence of cancer cells on biopsy. Endoscopic evaluation was performed with the same protocol of conventional chemoradiotherapy. Local recurrence after CCPT was treated with endoscopic resection for cT1a and with esophagectomy or photodynamic therapy for cT1b+. RESULTS: Of the 44 patients (median age, 70 years) that underwent CCPT, 43 patients (98%) achieved primary CR. Among the 44 patients, the 3-year overall survival rate was 95.2%. Five patients (11%) developed local recurrence without regional lymph node or distant metastasis and received endoscopic resection or photodynamic therapy. All five patients were alive with no recurrence after a median 23 months. CONCLUSIONS: The results suggest that CCPT is an effective treatment for cT1 ESCC and careful endoscopic follow-up allows preferable local control with salvage endoscopic treatment.

Effect of 5-fluorouracil on cellular response to proton beam in esophageal cancer cell lines according to the position of spread-out Bragg peak.

INTRODUCTION: To investigate enhancement by 5-fluorouracil (5-FU) of the sensitivity of cancer cells to proton beam irradiation and clarify the differences in the responses of the 5-FU-treated cells to proton beam irradiation according to the position of the cells on the spread-out Bragg peak (SOBP). METHODS: OE21 human esophageal squamous cells were irradiated with a 235-MeV proton beam at four different positions on the SOBP. The effects of the irradiation plus 5-FU treatment on the cell survival were assessed by clonogenic assays and determination of the sensitizer enhancement ratio (SER). In addition, DNA double-strand breaks were estimated by measuring phospho-histone H2AX (γH2AX) foci formation in the cells at 0.5 and 24 h after irradiation. RESULTS: The relative biological effectiveness (RBE) of proton beam irradiation against vehicle-control cells tended to increase with an increase in the depth of the cells on the SOBP. On the other hand, the degree of enhancement of the cellular sensitivity to proton beam irradiation by 5-FU was similar across all the positions on the SOBP. Furthermore, a marked increase in the number of residual γH2AX foci at 24 h post-irradiation was observed in the cells at the distal end of the SOBP. CONCLUSIONS: Our data indicated that the degree of enhancement by 5-FU of the sensitivity of OE21 cells to 235-MeV proton beam irradiation did not differ significantly depending on the position of the cells on the SOBP. Furthermore, the degree of increase in the number of γH2AX foci at 24 h after proton beam irradiation with or without 5-FU exposure did not differ significantly according to the position on the SOBP. The effect of 5-FU in enhancing the effect of proton beam irradiation on cancer cells may be constant for all positions on the SOBP.

Induction TPF chemotherapy followed by CRT with fractionated administration of cisplatin in patients with unresectable locally advanced head and neck cancer.

BACKGROUND: In treatment of locally advanced squamous cell carcinoma of the head and neck (SCCHN), the use of docetaxel, cisplatin, and 5-fluorouracil (TPF) followed by high-dose cisplatin chemoradiotherapy (CRT) carries concerns over toxicity. We evaluated the feasibility of TPF as induction chemotherapy (IC) to Japanese patients and the tolerability of CRT with fractionated administration of cisplatin after IC. METHODS: Patients with unresectable stage III, IV SCCHN received IC followed by CRT. IC consisted of three 3-week cycles of docetaxel 70-75 mg/m2 on day 1, cisplatin 70-75 mg/m2 on day 1, and 5-fluorouracil 750 mg/m2 on days 1-5. Patients subsequently received IMRT concomitant with fractionated administration of cisplatin (20 mg/m2) on days 1-4, repeated every 3 weeks. The primary endpoint was completion of the three cycles of IC. RESULTS: Forty-eight patients were enrolled. The IC treatment completion rate was 85%. Grade 3-4 toxicities of TPF were neutropenia (79%) and febrile neutropenia (15%). Thirty-eight patients (79%) achieved a response after IC. Forty patients subsequently underwent CRT. Thirty-three patients (83%) completed the planned cycles of fractionated administration of cisplatin, but seven (18%) did not. Grade 3-4 toxicities during CRT were neutropenia (23%), mucositis (53%), and dysphagia (33%). With a median follow-up of 36.1 months, 3-year overall survival was 65%. CONCLUSION: TPF IC is feasible and CRT with fractionated administration of cisplatin after IC is tolerable. IC followed by CRT appears to be a useful and safe sequential treatment. (Trial registration no. UMIN000024686).

Frequency and predictors of detecting early locoregional recurrence/disease progression of oral squamous cell carcinoma with high-risk factors on imaging tests before postoperative adjuvant radiotherapy.

BACKGROUND: To clarify the frequency and predictors of detecting early locoregional recurrence/disease progression (LR/DP) during the interval between surgery and postoperative adjuvant radiotherapy with/without chemotherapy in patients with oral squamous cell carcinoma. METHODS: Data on 65 patients who had undergone the initial radical surgery for previously untreated oral squamous cell carcinoma which were scheduled to receive adjuvant radiotherapy with/without chemotherapy were reviewed. RESULTS: Of the 65 patients, 63 (97%) were margin-positive/close and/or extracapsular extension-positive (hereinafter, high-risk factors). Eighteen (28%) patients had abnormal findings suggestive of LR/DP on postoperative imaging. Fifteen (23%) patients were diagnosed with LR/DP and treatment policy was changed. Univariate and multivariate analyses revealed higher frequencies of abnormal findings suggestive of LR/DP (univariate/multivariate analysis, p = 0.020/0.036), diagnosing of LR/DP, and changing the treatment policy (univariate/multivariate analysis, p = 0.042/0.046), among the patients who underwent postoperative diagnostic imaging tests or radiotherapy-planning contrast-enhanced (CE) CT without diagnostic imaging tests as compared with those who underwent radiotherapy-planning non-CECT without such tests. CONCLUSION: The frequency of detecting of early LR/DP before postoperative adjuvant treatment in oral squamous cell carcinoma patients with high-risk factors was high. Furthermore, postoperative diagnostic imaging tests and radiotherapy-planning CECT may be useful to detect early LR/DP in oral squamous cell carcinoma patients before postoperative adjuvant therapy.

Usefulness of hybrid deformable image registration algorithms in prostate radiation therapy.

To evaluate the accuracy of commercially available hybrid deformable image registration (DIR) algorithms when using planning CT (pCT) and daily cone-beam computed tomography (CBCT) in radiation therapy for prostate cancer. The hybrid DIR algorithms in RayStation and MIM Maestro were evaluated. Contours of the prostate, bladder, rectum, and seminal vesicles (SVs) were used as region-of-interest (ROIs) to guide image deformation in the hybrid DIR and to compare the DIR accuracy. To evaluate robustness of the hybrid DIR for prostate cancer patients with organs with volume that vary on a daily basis, such as the bladder and rectum, the DIR algorithms were performed on ten pairs of CT volumes from ten patients who underwent prostate intensity-modulated radiation therapy or volumetric modulated arc therapy. In a visual evaluation, MIM caused unrealistic image deformation in soft tissues, organs, and pelvic bones. The mean dice similarity coefficient (DSC) ranged from 0.46 to 0.90 for the prostate, bladder, rectum, and SVs; the SVs had the lowest DSC. Target registration error (TRE) at the centroid of the ROIs was about 2 mm for the prostate and bladder, and about 6 mm for the rectum and SVs. RayStation did not cause unrealistic image deformation, and could maintain the shape of pelvic bones in most cases. The mean DSC and TRE at the centroid of the ROIs were about 0.9 and within 5 mm generally. In both software programs, the use of ROIs to guide image deformation had the possibility to reduce any unrealistic image deformation and might be effective to keep the DIR physically reasonable. The pCT/CBCT DIR for the prostate cancer did not reduce the DIR accuracy because of the use of ROIs to guide the image deformation.

Palliative radiotherapy for breast cancer patients with skin invasion: a multi-institutional prospective observational study.

PURPOSE: To clarify the efficacy of palliative radiotherapy for the relief of symptoms due to skin invasion in patients with breast cancer. MATERIALS AND METHODS: We conducted a multi-institutional prospective observational study of patients who received palliative radiotherapy for skin invasion due to a primary lesion or chest wall recurrence. Bleeding/discharge, offensive odor, pain and QOL scores were evaluated before and 1, 3 and 6 months after radiotherapy. RESULTS: Twenty-one patients were assessed. Sixteen patients (76%) received 36 Gy in 12 fractions. The mean (±1 SD) score of bleeding/discharge was 1.90 ± 0.89 before radiotherapy, 1.50 ± 0.74 at 1 month, 0.47 ± 0.58 at 3 months, and 0.82 ± 1.04 at 6 months (P = 0.001). The mean score of offensive odor was 1.21 ± 1.38 before radiotherapy, 0.71 ± 0.92 at 1 month, 0.20 ± 0.41 at 3 months, and 0.27 ± 0.62 at 6 months (P = 0.008). The mean score of pain was 2.90 ± 1.22 before radiotherapy, 3.05 ± 1.36 at 1 month, 3.29 ± 1.10 at 3 months, and 3.31 ± 1.54 at 6 months (P = 0.431). The mean total score of QOL-ACD/QOL-ACD-B was 126.2 ± 24.5 before radiotherapy, 130.3 ± 26.3 at 1 month, 136.2 ± 26.6 at 3 months, and 126.6 ± 32.8 at 6 months (P = 0.178). CONCLUSION: Palliative radiotherapy for skin invasion in patients with breast cancer might be effective, especially for the relief of bleeding/discharge and offensive odor.

The 5-year outcomes of moderately hypofractionated radiotherapy (66 Gy in 22 fractions, 3 fractions per week) for localized prostate cancer: a retrospective study.

BACKGROUND: Hypofractionated radiotherapy using fewer and larger fractional doses may be more beneficial than conventional external-beam radiotherapy for localized prostate cancer. We evaluated the 5-year outcomes of moderately hypofractionated radiotherapy for localized prostate cancer. METHODS: We retrospectively evaluated 195 patients with localized prostate cancer (T1-3N0M0) who underwent intensity-modulated radiotherapy (IMRT) (66 Gy delivered in fractions of 3 Gy every other weekday) between May 2005 and December 2011. Patients received androgen deprivation therapy depending on the perceived intermediate or high risk of their disease. A prostate-specific antigen nadir +2.0 ng/ml indicated biochemical failure. We assessed toxicity using the Radiation Therapy Oncology Group and the European Organization for Research and Treatment of Cancer (RTOG/EORTC) criteria, and patient-reported outcomes using the Expanded Prostate Cancer Index Composite (EPIC). RESULTS: The risk classifications (proportion) were low risk (13.8%), intermediate risk (35.9%), and high risk (50.3%). The median follow-up was 69 months. Thirteen (6.66%) patients experienced biochemical failure within a median of 40 months (interquartile range, 25-72 months). The 5-year overall survival rate and no biological evidence of disease rate were 97.7% and 92.4%, respectively. Based on the RTOG/EORTC criteria, no patient experienced acute or late toxicity of grade 3 or higher. The EPIC scores revealed significant differences in the average value of all domains (p < 0.01). At 1 month postradiotherapy completion, the general urinary and bowel domain scores had decreased, but these scores returned to baseline level by 3 months post radiotherapy. CONCLUSIONS: The moderately hypofractionated radiotherapy protocol yielded short-term satisfactory clinical outcomes with acceptable toxicity.

Pharmacokinetics of initial full and subsequent reduced doses of S-1 in patients with locally advanced head and neck cancer-effect of renal insufficiency.

BACKGROUND: S-1 is a combination of tegafur [metabolized to 5-fluorouracil (5-FU)] with the modulators gimeracil (5-chloro-2,4-dihydroxypyridine) and oteracil potassium. 5-Chloro-2,4-dihydroxypyridine maintains plasma 5-FU concentrations by inhibiting dihydropyrimidine dehydrogenase, a pyrimidine catabolism enzyme that degrades 5-FU. As 50% of 5-chloro-2,4-dihydroxypyridine is excreted in urine, renal insufficiency may increase its blood level, increasing 5-FU concentrations. We investigated whether special dose modification is needed in the presence of renal insufficiency. OBJECTIVE: We compared steady state pharmacokinetics of 5-FU for the initial S-1 dose and reduced doses in patients with head and neck cancer requiring dose reduction due to renal and non-renal toxicities. METHODS: Chemoradiotherapy with S-1 and cisplatin was administered every 5 weeks for two courses with a radiation dose totaling 70 Gy over 33-35 fractions. Two additional courses of adjuvant chemotherapy were administered in the case of an objective response. The S-1 and/or cisplatin dose was reduced in response to renal, hematologic or other toxicities. The primary endpoint was the change in area under the plasma concentration-versus-time curve from time 0-10 hours (5-FU AUCss 0-10) between the initial and reduced S-1 doses. RESULTS: Although the mean 5-FU levels in patients with non-renal toxicities significantly decreased between the full and reduced dose, the full-dose and reduced-dose mean maximum 5-FU plasma concentrations at steady state (Css max) and AUCss 0-10 in patients with renal insufficiency were similar. CONCLUSIONS: Standard S-1 dose reduction for renal toxicity did not result in a significant decrease in 5-FU levels at steady state. A greater reduction to lower plasma 5-chloro-2,4-dihydroxypyridine may be necessary in patients with renal insufficiency.

Parallel Post-Polyketide Synthase Modification Mechanism Involved in FD-891 Biosynthesis in Streptomyces graminofaciens A-8890.

To isolate a key polyketide biosynthetic intermediate for the 16-membered macrolide FD-891 (1), we inactivated two biosynthetic genes coding for post-polyketide synthase (PKS) modification enzymes: a methyltransferase (GfsG) and a cytochrome P450 (GfsF). Consequently, FD-892 (2), which lacks the epoxide moiety at C8-C9, the hydroxy group at C10, and the O-methyl group at O-25 of FD-891, was isolated from the gfsF/gfsG double-knockout mutant. In addition, 25-O-methyl-FD-892 (3) and 25-O-demethyl-FD-891 (4) were isolated from the gfsF and gfsG mutants, respectively. We also confirmed that GfsG efficiently catalyzes the methylation of 2 and 4 in vitro. Further, GfsF catalyzed the epoxidation of the double bond at C8-C9 of 2 and 3 and subsequent hydroxylation at C10, to afford 4 and 1, respectively. These results suggest that a parallel post-PKS modification mechanism is involved in FD-891 biosynthesis.

Impact of prophylactic percutaneous endoscopic gastrostomy tube placement on treatment tolerance in head and neck cancer patients treated with cetuximab plus radiation.

OBJECTIVE: We conducted a retrospective analysis to evaluate the efficacy and safety of cetuximab plus radiation with or without prophylactic percutaneous endoscopic gastrectomy in locally advanced squamous cell carcinoma of the head and neck patients who were not suitable to receive platinum. PATIENTS AND METHODS: We reviewed the case records of 27 locally advanced squamous cell carcinoma of the head and neck patients treated with cetuximab plus radiation (RT) between January 2013 and July 2014. No patient was able to receive platinum because of renal dysfunction or other contraindications. Patients received an initial dose of cetuximab of 400 mg/m(2), followed by weekly doses of 250 mg/m(2). The total dose of radiotherapy was 66-70 Gy in five daily fractions of 2-2.12 Gy per week. RESULTS: The incidence of leukopenia was significantly higher in patients without percutaneous endoscopic gastrectomy placement than in those with (67.5% vs. 7%, P = 0.002). The incidence of Grade 3 or 4 mucositis tended to be higher in patients without percutaneous endoscopic gastrectomy placement than in those with (83% vs. 47%, P = 0.058). Five of twelve patients without percutaneous endoscopic gastrectomy placement required interruption of treatment. More patients without percutaneous endoscopic gastrectomy placement had significantly >10% weight loss than patients with (75% vs. 27%, P = 0.013). The overall response rate was 56% in all patients. The 1-year progression-free survival rate was 30.6% in all patients. CONCLUSIONS: Prophylactic percutaneous endoscopic gastrectomy-feeding tube placement could reduce the incidence of severe toxicities, including mucositis and weight loss, and avoid RT interruption. These results require confirmation in a larger study.