Tumor volume instead of recurrent T category predicts clinical outcome of patients with locally recurrent nasopharyngeal carcinoma salvaged by carbon ion radiation therapy.

BACKGROUND: Although carbon ion radiation therapy (CIRT) substantially improves the overall survival (OS) of patients with LR-NPC, approximately 40% of the patients may develop local recurrence. The purpose of study is to assess the value of tumor volume (TV) as a predictive tool to guide individualized CIRT. METHODS: Consecutive patients with LR-NPC treated using CIRT at Shanghai Proton and Heavy Ion Center between April 2015 and May 2019 were included. TV before CIRT was delineated and calculated. The generalized additive Cox model was used to examine the relationship between TV and OS and local progression-free survival (LPFS). A cutoff value of tumor volume was identified to best discriminate patients with different 2-year OS rates, using receiver operating characteristic (ROC) analysis. RESULTS: A total of 157 patients were enrolled. The median tumor volume was 22.49 (2.52-90.13) ml. In the univariable analyses, tumor volume was significantly associated with OS (p < 0.001) and LPFS (p = 0.01). The relationships with OS (p = 0.009) and LPFS (p = 0.020) remained significant in multivariable analyses. Using ROC analysis, a TV of 26.69 ml was identified to predict the 2-year OS rate. To facilitate potential clinical use, 25 ml was designated as the final cutoff value. The 2-year OS and LPFS rates were 88.6 % vs 62.3 %, and 54.7 % vs 35.5 %, for patients with a TV ≤ 25 ml and > 25 ml, respectively. CONCLUSION: Tumor volume could predict the OS and LPFS of patients. We propose that tumor volume should be considered in the risk stratification and CIRT-based treatment for patients with LR-NPC.

A protocol for a randomized trial evaluating the role of carbon-ion radiation therapy plus camrelizumab for patients with locoregionally recurrent nasopharyngeal carcinoma.

PURPOSE: Management of locoregionally recurrent nasopharyngeal carcinoma (LR NPC) is difficult. Although carbon-ion radiation therapy (CIRT) could substantially improve the overall survival (OS) of those patients, around 40% of the patients may still develop local failure. Further improvement of the disease control is necessary. Immunotherapy, such as immune checkpoint inhibitors (ICIs) becomes a promising antitumor treatment. The role of ICIs was proved in head and neck cancers including recurrent/metastatic NPC. Preclinical studies indicated potential synergistic effects between radiation therapy and ICIs. Therefore, we conduct a randomized phase 2 trial to evaluate the efficacy and safety of camrelizumab, an anti-PD-1 monoclonal antibody, along with CIRT in patients with LR NPC. METHODS: Patients will be randomly assigned at 1:1 to receive either standard CIRT with 63 Gy (relatively biological effectiveness, [RBE]) in 21 fractions, or standard CIRT plus concurrent camrelizumab. Camrelizumab will be administered intravenously with a dose of 200 mg, every 2 week, for a maximum of 1 year. We estimate addition of camrelizumab will improve the 2-year progression-free survival (PFS) from 45% to 60%. A total of 146 patients (with a 5% lost to follow-up rate) is required to yield a type I error of 0.2, and a power of 0.8. RESULTS AND CONCLUSION: The results of the trial may shed insights on the combined therapy with ICIs and CIRT.

Carbon ion radiotherapy combined with immunotherapy: synergistic anti-tumor efficacy and preliminary investigation of ferroptosis.

Carbon ion radiotherapy (CIRT) may yield satisfactory clinical outcomes for patients who are resistant to radiotherapy. However, the therapeutic impact of carbon ions is still limited in certain recurring or refractory tumors. Therefore, we aimed to evaluate the synergistic anti-tumor effects of immune checkpoint inhibitors (ICIs) in combination with CIRT. We then explored the involvement of ferroptosis in a preliminary investigation. A tumor-bearing mouse model was established, and mice were inoculated subcutaneously with B16-OVA cells into the flanks of both hind legs. Mice were assigned to four groups to receive CIRT, ICIs, or combined treatment. Thereafter, we conducted transcriptome sequencing (RNA-seq), bioinformatics analysis, and various immune-related experiments on the available tumor tissues to investigate differences in the synergistic anticancer effects and potential mechanisms across the groups. The combination therapies significantly improved the survival of mice and inhibited tumor growth, both at local and distant sites. Based on bioinformatics and RNA-seq data, immune-related pathways and genes, immune cell infiltration, and the production of cytokines and chemokines were the most enhanced in the combined treatment group compared to other groups. Finally, we identified a potential role for ferroptosis in the development of local anti-tumor synergy during CIRT combination treatment. In conclusion, this study showed that CIRT and ICIs can enhance the anti-tumor immune effects. We also proposed that ferroptosis may induce anti-tumor effects in CIRT combination therapy, offering a unique perspective on its ability to enhance immunotherapy responses.

Preliminary clinical outcomes of head and neck squamous cell carcinoma treated with particle beam radiation therapy.

PURPOSE: Further improvement in clinical outcomes is needed for patients with head and neck squamous cell carcinoma (HNSCC), as there is typically a poor prognosis at diagnosis. This study aimed to report the preliminary therapeutic outcomes and side effects in patients with HNSCC receiving particle beam radiotherapy (PBRT), owing to the physical and biological advantages of this approach. METHODS: We retrospectively analyzed 68 patients with newly diagnosed HNSCC who received PBRT at the Shanghai Proton and Heavy Ion Center (SPHIC) between August 2015 and December 2020. The Kaplan-Meier approach was used to determine overall survival (OS), disease-specific survival (DSS), progression-free survival (PFS), local recurrence-free survival (LRFS), regional recurrence-free survival (RRFS), and distant metastasis-free survival (DMFS). Common Terminology Criteria for Adverse Events (CTCAE) 4.03 was also used to grade acute and late toxicities. RESULTS: With a median follow-up time of 24.5 months (range, 3-65), the 3-year OS, DSS, PFS, LRFS, RRFS, and DMFS rates for the entire cohort were 79.0%, 84.7%, 67.9%, 83.5%, 83.3%, and 96.1%, respectively. Univariate and multivariate analyses showed that N category was a significant predictor of OS, PFS, and RRFS. In terms of acute toxicities, two patients demonstrated severe mucositis or dysphagia, and two patients also displayed a late toxicity of significant mucosal necrosis. CONCLUSION: These findings suggest that PBRT can provide patients with HNSCC with a promising therapeutic benefit and manageable toxicity. Prospective evaluation of clinical outcomes with PBRT for HNSCC is warranted, with an emphasis on clinical effectiveness as well as adverse effects and patient quality of life.

In vitro evaluation of photon and carbon ion radiotherapy in combination with cisplatin in head and neck squamous cell carcinoma cell lines.

Background: Heavy ion radiotherapy, such as carbon ion radiotherapy (CIRT), has multiple advantages over conventional photon therapy. Cisplatin, as a classic anti-tumor drugs, has been tested and discovered as a photon radiosensitizer in several cell lines, including head and neck squamous cell carcinoma (HNSCC). Hence, the aim of our study is to evaluate whether cisplatin can sensitize CIRT towards HNSCC cell lines in vitro. Methods: Human nasopharyngeal carcinoma cell line CNE-2, human tongue squamous carcinoma cell line TCA 8113 and human hypopharynx squamous carcinoma cell line FADU were all irradiated with photon beam of 2, 4, 6, 8 Gy (physical dose) and carbon ion beam of 1, 2, 3, 4 Gy (physical dose) and treated with cisplatin. Cell survival was assessed by clonogenic survival assay. Results: CIRT showed significantly stronger cytotoxic effect than standard photon radiotherapy. The relative biological effectiveness (RBE) of carbon ion beam at 10% survival ( R B E 10 ) was calculated 3.07 for CNE-2, 2.33 for TCA 8113 and 2.36 for FADU. Chemoradiotherapy (both photon radiotherapy and CIRT) was more effective than radiotherapy alone. In vitro sensitizer enhancement ratios (SERs) of cisplatin in CNE-2, TCA 8113 and FA DU cell lines after photon irradiation were 1.33, 1.14 and 1.21, while after carbon ion irradiation were 1.02, 1.00 and 0.96, showed that cisplatin sensitized photon irradiation but showed no sensitization effect in carbon ion irradiation in all tested cell lines. Conclusions: In conclusion, high linear energy transfer (LET) CIRT was more effective than photon irradiation to prevent the proliferation of HNSCC cell lines. Additional treatment with cisplatin could sensitize photon irradiation but showed no effect on carbon ion irradiation.

Development of a normal tissue complication probability (NTCP) model using an artificial neural network for radiation-induced necrosis after carbon ion re-irradiation in locally recurrent nasopharyngeal carcinoma.

Background: The aim of the present study was to build a normal tissue complication probability (NTCP) model using an artificial neural network (ANN) for radiation-induced necrosis after carbon ion re-irradiation in locally recurrent nasopharyngeal carcinoma (rNPC), and to determine the predictive parameters applied to the model. Methods: A total of 150 patients with rNPC treated at Shanghai Proton and Heavy Ion Center during 2015-2019 were selected to determine the dominant factors causing mucosal necrosis after carbon therapy. An ANN was built to study both dose-volume histogram (DVH) and clinical factors. Simple oversampling and data normalization were used in the training process. Ten-fold cross validation was conducted to prevent overfitting. Results: Of the DVH factors, the prediction accuracy ranged from 58.3-65.2%, whereas planning target volume (PTV) receiving dose more than 25 GyE (PTV.V25) yielded the best prediction accuracy. Of the clinical factors, baseline necrosis, sex, and biologically equivalent dose (BED) of initial treatment could increase the accuracy of PTV.V25 by 0.5%, 0.5%, and 1.5%, respectively. Conclusions: An ANN was built to predict radiation-induced necrosis after re-irradiation in rNPC. The best accuracy and area under receiver-operating characteristic (ROC) curve (AUC) were 66.7% and 0.689. The most predictive dosimetric and clinical parameters were PTV.V25 and BED of initial treatment.

Comparison of the efficacy and toxicity of postoperative proton versus carbon ion radiotherapy for head and neck cancers.

Background: To compare the efficacy and toxicity of adjuvant proton beam vs. carbon-ion beam radiotherapy for head and neck cancers after radical resection and to explore the value of particle beam radiotherapy (PBRT) in postoperative radiotherapy for head and neck cancers. Methods: Data from 38 head and neck cancer patients who received adjuvant PBRT after complete surgical resection at the Shanghai Proton and Heavy Ion Center (SPHIC) between October 2015 and March 2019 were retrospectively analyzed. In total, 18 patients received adjuvant proton beam therapy (54-60 GyE/27-30 fractions) and 20 received adjuvant carbon-ion radiotherapy (CIRT) (54-60 GyE/18-20 fractions). Survival rates were calculated using Kaplan-Meier analysis. Toxicity was evaluated according to the Common Terminology Criteria for Adverse Effects (version 4.03). Results: With a median follow-up time of 21 (range, 3-45) months, the 2-year overall survival (OS), progression-free survival (PFS), local-regional recurrence-free survival (LRRFS) and distant metastasis-free survival (DMFS) rates were 93.3%, 87.4%, 94.1%, and 90.7%, respectively, for the entire cohort. The rates after proton beam therapy vs. CIRT were 94.1% vs. 91.7% (P=0.96), 88.1% vs. 86.2% (P=0.96), 94.4% vs. 93.3% (P=0.97), and 88.1% vs. 92.9% (P=0.57), respectively. Furthermore, 16 of the 18 (88.9%) patients developed acute grade I/II dermatitis (13 grade I; 3 grade II) after proton beam therapy, and only 7 of the 20 (35%) patients developed acute grade I dermatitis after CIRT (P=0.001). The incidence of acute grade I/II mucositis and xerostomia in proton and carbon ion cases were 45% vs. 55% (P=0.75) and 56% vs. 50% (P=0.87) respectively. Conclusions: Adjuvant proton beam therapy and CIRT after radical surgical resection for head and neck cancers provided satisfactory therapeutic effectiveness, but no significant difference was observed between the two radiotherapy technologies. However, adjuvant CIRT was associated with a more favorable acute toxicity profile as compared to proton beam therapy with significantly lower frequency and severity of acute dermatitis observed.

Intensity-modulated proton and carbon-ion radiation therapy in the management of major salivary gland carcinomas.

Background: Primary major salivary gland carcinomas (SGCs) present with diverse histological types that are known to be largely radioresistant with a high tendency to develop distant metastasis (DM). Photon-based radiotherapy (RT) is limited in terms of its therapeutic effect and toxicities. In view of the physical and biological advantages of intensity-modulated proton and/or carbon-ion radiation therapy, we aimed to evaluate the short-term therapeutic effect and toxicities in patients with major SGCs treated with this form of radiation therapy. Methods: Between August 2015 and November 2019, a total of 55 consecutive and non-selected major SGC patients who received particle RT at the Shanghai Proton and Heavy Ion Center (SPHIC) were retrospectively analyzed. The 2-year overall survival (OS), progression-free survival (PFS), local-regional recurrence-free survival (LRRFS), and distant metastasis-free survival (DMFS) rates, as well as prognostic factors were analyzed. Additionally, acute and late toxicities were also analyzed. Results: With a median follow-up time of 24 (range, 6-57) months, the 2-year OS, PFS, LRRFS, and DMFS rates were 91.6%, 78.6%, 94.2%, and 83.9%, respectively. At the time of this analysis, four patients had developed local or regional recurrence, and seven additional patients had developed DM. Three patients had died due to disease progression, and another patient with recurrence experienced a late Grade 5 event (hemorrhage) at 9 months after re-irradiation with carbon ion and subsequently died. Otherwise, none of the patients had grade 3 or higher treatment-induced acute or late adverse effects except one who developed grade 3 acute mucositis. Conclusions: Overall, intensity-modulated proton and/or carbon-ion radiation therapy provided satisfactory therapeutic effectiveness in our major SGCs patients with a low incidence of acute and late toxicities.

Biological Guided Carbon-Ion Microporous Radiation to Tumor Hypoxia Area Triggers Robust Abscopal Effects as Open Field Radiation.

Recently, a growing number of studies focus on partial tumor irradiation to induce the stronger non-target effects. However, the value of partial volume carbon ion radiotherapy (CIRT) targeting hypoxic region of a tumor under imaging guidance as well as its effect of inducing radiation induced abscopal effects (RIAEs) have not been well investigated. Herein, we developed a technique of carbon ion microporous radiation (CI-MPR), guided by 18F-FMISO PET/computerized tomography (CT), for partial volume radiation targeting the hypoxia area of a tumor and investigated its capability of inducing abscopal effects. Tumor-bearing mice were inoculated subcutaneously with breast cancer 4T1 cells into the flanks of both hind legs of mouse. Mice were assigned to three groups: group I: control group with no treatment; group II: carbon ion open field radiation (CI-OFR group) targeting the entire tumor; group III: partial volume carbon ion microporous radiation (CI-MPR group) targeting the hypoxia region. The tumors on the left hind legs of mice were irradiated with single fraction of 20 Gy of CIRT. Mice treated with CI-MPR or CI-OFR showed that significant growth delay on both the irradiated and unirradiated of tumor as compared to the control groups. Tumor regression of left tumor irradiated with CI-OFR was more prominent as compared to the tumor treated with CI-MPR, while the regression of the unirradiated tumor in both CI-MPR and CI-OFR group was similar. Biological-guided CIRT using the newly developed microporous technique targeting tumor hypoxia region could induce robust abscopal effects similar to CIRT covering the entire tumor.

The Impacts of Different Types of Radiation on the CRT and PDL1 Expression in Tumor Cells Under Normoxia and Hypoxia.

INTRODUCTION: Hypoxia is a hallmark of cancer that may contribute to an immunosuppressive microenvironment and promote radioresistance. High linear energy transfer (LET) radiation is considered to be able to overcome the negative effects of hypoxia. However, the anti-tumorigenic effects induced by low or high LET radiation have not been fully elucidated. This study aimed to compare the effects of different types of radiation on the immune response, particularly the impact on calreticulin (CRT), and programmed cell death ligand 1 (PDL1) expression. METHODS: Four human tumor cell lines were investigated in this study. Cells in normoxic and hypoxic groups were irradiated with 4Gy (physical dose) photon, proton, and carbon-ion radiation, respectively. The expression of CRT and PDL1 was detected 48 h after irradiation, and the median fluorescence intensities (MFIs) were compared by flow cytometry. Meanwhile, the radiosensitivity of tumor cells in each group was also compared by colony formation assays and flow cytometry. RESULTS: All types of radiation could significantly inhibit the colony formation of tumor cells under normoxia. However, the efficacy of photon and proton radiation was impaired under hypoxia. Carbon-ion radiation could still inhibit colony formation. The percentage of viable cells after irradiation was higher under hypoxia compared with those under normoxia. The CRT expression under normoxia was significantly increased after radiation. Carbon-ion radiation enhanced CRT expression compared to photon and proton radiation. Conversely, under hypoxia, the CRT expression level was significantly upregulated at baseline (0Gy). Radiation could not increase the expression further. PDL1 expression was also significantly increased by radiation under normoxia in all cell lines except the Ln18 cell line. Carbon-ion radiation induced the most significant increase. Under hypoxia, the PDL1 expression level was also upregulated at baseline and radiation could not increase expression further. CONCLUSION: Tumor cells were resistant to photon and proton but sensitive to carbon-ion radiation under hypoxia. Carbon-ion radiation could induce the highest CRT and PDL1 expression under normoxia. However, under hypoxia, radiation could not further enhance the high baseline expression of CRT and PDL1.

Comparison of the effects of photon, proton and carbon-ion radiation on the ecto-calreticulin exposure in various tumor cell lines.

BACKGROUND: Accumulating evidence suggested that radiotherapy can activate anti-tumor immune responses by triggering immunogenic cell death (ICD) of tumor cells. Calreticulin is regarded as one of the most important markers of ICD. The cell surface translocation of calreticulin (ecto-CRT) serves as an "eat me" signal for phagocytosis of dying cells, which plays a pivotal role in activating anti-tumor immunity. However, there is limited knowledge describing the effects of proton and carbon-ion radiation on ecto-CRT exposure. Hence, we investigated ecto-CRT exposure in multiple human carcinoma cell lines irradiated by proton and carbon-ion in comparison to photon. METHODS: This study examined four human cancer cell lines including A549 (lung adenocarcinoma), U251MG (glioma), Tca8113 (tongue squamous carcinoma), and CNE-2 (nasopharyngeal carcinoma). Cell lines were irradiated with photon, proton or carbon-ion at 0, 2, 4, 10 Gy (physical dose). The ecto-CRT exposure level was analyzed by flow cytometry at 12, 24, and 48 h post-irradiation. The median fluorescence intensity was calculated by FlowJo. RESULTS: All three types of radial beam increased ecto-CRT exposure of the 4 tumor cell lines in a time-dependent manner. Ecto-CRT exposure significantly elevated 1.5-2.4 times over 48 h post-irradiation compared with controls (P<0.05). Proton and photon increased ecto-CRT exposure with dose escalation. Photon and proton at 10 Gy increased the most ecto-CRT exposure (P<0.05), while carbon-ion increased most ecto-CRT exposure at 4 Gy rather than 10 or 2 Gy. When compared with iso-physical dose at 48 h post-irradiation, proton showed a similar effectiveness with photon. While carbon-ion has significantly stronger effects on increasing ecto-CRT than proton and photon at 2 and 4 Gy, but changed oppositely at 10 Gy (P<0.05). CONCLUSIONS: All the three types of radiation can increase the ecto-CRT exposure in a time-dependent manner. Proton and photon radiation were equally effective in inducing ecto-CRT exposure, while carbon-ion revealed a different effectiveness in comparison to photon and proton.

Upregulated necroptosis-pathway-associated genes are unfavorable prognostic markers in low-grade glioma and glioblastoma multiforme.

BACKGROUND: Glioma accounts for 70% of primary brain malignancies in adults with unfavorable prognoses. In the past decades, much efforts have been invested to identify better biomarkers for predicting prognoses. Recently, necroptosis has been reported as a specialized pathway of programmed necrosis. Moreover, regulators of necroptosis-pathway-associated genes (RIPK1, RIPK3 and MLKL) were reported to be related to prognoses of many types of tumors. However, the prognostic value of these genes in diffuse glioma including low-grade glioma (LGG) and glioblastoma multiforme (GBM) remains unknown. METHODS: An online tool-Gene Expression Profiling Interactive Analysis (GEPIA) (http://gepia.cancer-pku.cn/) was used to analyze different expression of necroptosis-pathway-associated genes between tumor and normal tissue, correlation between RIPK1, RIPK3 and MLKL, the relationship between necroptosis-pathway-associated genes and prognosis [overall survival (OS) and disease-free survival (DFS)] in LGG and GBM. The median expression of RIPK1, RIPK3 and MLKL was used to divide patients into high- versus low-expression group. All graphic presentations were drawn by Gepia database. RESULTS: Expression of RIPK1 and RIPK3 were significantly higher in tumor tissue of GBM as compared with normal tissue. A moderate correlation between MLKL and RIPK3 was demonstrated in both LGG (R =0.79) and GBM (R =0.79). In LGG, higher expression of RIPK1, RIPK3, and MLKL were associated with poor OS and DFS with HR values of 2.2, 2, 1.9 for OS and 1.7, 1.8, 1.6 for DFS, respectively. In GBM, only a higher expression of MLKL was associated with worse OS and DFS with HR values of 1.5 and 1.6, respectively. CONCLUSIONS: Regulators of necroptosis-pathway-associated genes appear to have a potential to serve as biomarkers of prognosis in both LGG and GBM.

Depletion of MLKL inhibits invasion of radioresistant nasopharyngeal carcinoma cells by suppressing epithelial-mesenchymal transition.

BACKGROUND: To examine whether MLKL participated in the invasion of radiosensitive nasopharyngeal carcinoma (NPC) cell (CNE-2) and radioresistant NPC cell (CR) through regulating epithelial-mesenchymal transition (EMT). METHODS: siRNA and CRISPR/Cas9 technique were used to decrease MLKL expression in NPC cell (CNE-2 and CR). Trans-well assay was conducted to evaluate invasion. Gene expression profiling was performed using Human U133 2.0 plus arrays (Affymetrix). Kyoto Encyclopedia of Genes and Genomes (KEGG) was adopted to analyze gene expression profiling. Hub genes at a functional level were accessed by protein-to-protein network (PPI). Quantitative real-time PCR and Western blot were used to access EMT markers. RESULTS: Invasion of CR was about 3~fold change higher than that of CNE-2. Silencing MLKL by siRNA inhibited invasion of CR, not CNE-2. Further, depleting MLKL by CRISPR-Cas9 in CR (CR-MLKL KO) also inhibited its invasion. KEGG pathway analysis showed invasion-related pathways were altered, such as adherent junction, TGF-ß signaling pathway. PPI demonstrated that compared with CNE-2, CR showed 9 elevated hub genes including EGFR, JUN, CD44, SPP1, VIM, IL-8, BCL2, WDFY2, PIK3CD and 1 downregulated hub gene CDH1. After MLKL depletion, 8 hub genes were downregulated (EGFR, JUN, CD44, SPP1, VIM, FGF13, PLAU, MMP1) and 2 hub genes were upregulated (MMP9, CDH1). Quantitative real-time PCR results showed that compared with CNE-2, CR displayed decreased epithelial markers significantly (E-Cadherin) and increased mesenchymal markers significantly (Vimentin, N-Cadherin, Zeb1), indicating irradiation-induced EMT. After depletion of MLKL in CR, the expression of E-Cadherin, Vimentin, N-Cadherin, Zeb1 was reversed to the level of CNE-2. Western blot confirmed the results from qRT-PCR. CONCLUSIONS: Depletion of MLKL efficiently inhibits invasion of radioresistant NPC by suppressing EMT. MLKL may be an important target to suppress distant metastasis of NPC patients who relapsed after radiotherapy.

Clinical outcome of palliative radiotherapy for locally advanced symptomatic gastric cancer in the modern era.

The purpose of this study was to report the outcomes of patients with symptomatic locally advanced/recurrent gastric cancer treated with radiotherapy (RT) using modern 3-dimensional conformal techniques.We retrospectively reviewed patients who had palliative RT for index symptoms of gastric bleeding, pain, and obstruction. Study endpoints included symptom response, median survival, and treatment toxicity.Of 115 patients with median age of 77 years, 78 (67.8%) patients had metastatic disease at the time of treatment. Index symptoms were gastric bleeding, pain, and obstruction in 89.6%, 9.2%, and 14.3% of patients, respectively. Dose fractionation regimen ranged from 8-Gy single fraction to 40 Gy in 16 fractions. One hundred eleven patients (93.3%) were computed tomography (CT) planned. Median follow-up was 85 days. Response rates for bleeding, pain, and obstruction were 80.6% (83/103), 45.5% (5/11), and 52.9% (9/17), respectively, and median duration of response was 99 days, 233 days, and 97 days, respectively. Median survival was 85 days. Actuarial 12-month survival was 15.3%. There was no difference in response rates between low (≤39 Gy) and high (>39 Gy) biologically effective dose (BED) regimens (α/ß ratio = 10). Median survival was significantly longer in patients who responded to RT compared with patients who did not (113.5 vs 47 days, P < 0.001). Three patients (2.6%) had grade 3 Common Toxicity Criteria equivalent toxicity (nausea/vomiting/anorexia).External beam RT delivered using 3-dimensional conformal techniques is highly effective and well tolerated in the local palliation of gastric cancer, with palliation lasting the majority of patient's lives. Short (≤39 Gy BED) RT schedules are adequate for effective symptom palliation. A phase II study of palliative gastric RT is ongoing.

Postoperative chemo-radiotherapy versus chemotherapy for resected gastric cancer: a systematic review and meta-analysis.

INTRODUCTION: This study conducted a systematic review and meta-analysis (direct and indirect) of published randomised controlled trials (RCTs) to compare the effects of postoperative chemo-radiotherapy (ChRT) with chemotherapy (Ch) on overall and disease-free survival (DFS) for patients with resectable gastric cancer. METHODS: We searched MEDLINE and CENTRAL from the date of inception and annual meeting proceedings of American Society of Clinical Oncology and American Society for Radiation Oncology from 1999 to November 2012 for RCTs comparing postoperative ChRT with Ch, postoperative ChRT with surgery alone and postoperative Ch with surgery alone. The primary outcome was overall survival (OS); secondary outcomes included DFS and toxicity. Hazard ratios (HRs), confidence intervals (CIs) and P values (P) were estimated with fixed effects models using Revman 5.1. RESULTS: We found six trials comparing postoperative ChRT with Ch (n = 1171). Meta-analysis of direct comparison trials showed that postoperative ChRT significantly improved both OS (HR 0.80, 95% CI 0.65-0.98, P = 0.03) and DFS (HR 0.76, 95% CI 0.63-0.91, P = 0.003) when compared with Ch. There were no significant differences in toxicity between the two groups. CONCLUSIONS: This study suggests a survival benefit of postoperative ChRT over Ch in patients with resected gastric cancer.

Update report of nasopharyngeal carcinoma treated with reduced-volume intensity-modulated radiation therapy and hypothesis of the optimal margin.

BACKGROUND AND PURPOSE: To establish the minimally required margins in different directions measured from GTV in the definitive treatment of nasopharyngeal carcinoma (NPC) using IMRT based on the 5-year results. METHODS AND MATERIALS: Between November 2003 and May 2007, 414 patients with non-metastatic NPC were treated with IMRT according to our institutional protocol. Treatment outcomes at 5 years were analyzed. Distances from GTV-T to CTV2 (i.e., CTV 59.4 Gy) in 6 directions (anterior, posterior, superior, inferior, and bilateral) were measured and analyzed. RESULTS: The 5-year estimated overall survival (OS), disease free survival (DFS), local control (LC) were 80%, 77% and 95%, respectively. For the margins measured from GTV-T to CTV2, margins used with T4 disease were significantly and uniformly smaller than the whole group in all the 6 directions (P=0.000, 0.000, 0.000, 0.000 and 0.046, respectively). However, no increase of local recurrence was associated to this limited margins used. CONCLUSIONS: Our 5-years' experience showed a very high LC rate. The strategy we used for CTV delineation was safe and reliable. Determined CTV through GTV expansion to a minimally required margin, using GTV+margin (used in our T4 patients)+the whole nasopharyngeal mucosa, especially for the patients with early T disease, might be feasible.

Body mass index and patient CT measurements as a predictor of benefit of intensity-modulated radiotherapy to the supraclavicular fossa.

BACKGROUND: Irradiation of the supraclavicular fossa is commonly used as part of adjuvant breast radiotherapy. Intensity-modulated radiotherapy (IMRT) may be used to target this region accurately, and there are subgroups of patients that may benefit more from IMRT than others. We identify the benefit of IMRT over fixed-depth dose prescription to the supraclavicular fossa in patients of different builds in a clinical setting. METHODS: Fifteen patients who received radiotherapy to the left breast and supraclavicular fossa were selected. Computed tomographic planning was used to generate plans for supraclavicular fossa coverage. Dose prescription to 1.5 cm and 3.0 cm depths was compared with IMRT plans. Coverage of the planning target volume and dose to the organs at risk were compared and correlated with patient body mass index (BMI) and computed tomography measurements. RESULTS: Within the IMRT group, increasing depth of the supraclavicular fossa produced significantly better coverage of the planning target volume with IMRT. IMRT resulted in lower mean doses to the brachial plexus (P = 0.00) when compared with 1.5 cm and 3 cm depth dose prescriptions, but higher maximum brachial plexus doses. IMRT was more beneficial in patients with lower BMI because this resulted in a decreased maximum brachial plexus dose (P-values of 0.03 and 0.001 when compared with 1.5 cm and 3.0 cm depth dose prescriptions, respectively). Higher patient BMI resulted in a lower dose contribution of IMRT to the cord (P-values 0.066 and 0.034 when compared with 1.5 cm and 3.0 cm depth dose prescriptions respectively). CONCLUSION: IMRT of the supraclavicular fossa results in lower brachial plexus doses for patients with low BMI while patients with higher BMI benefit from lower mean cord doses. IMRT provides superior coverage of the planning target volume, especially in patients with a deeper supraclavicular fossa.

Neoadjuvant chemotherapy followed by concurrent chemoradiation for locoregionally advanced nasopharyngeal carcinoma: interim results from 2 prospective phase 2 clinical trials.

BACKGROUND: The authors studied the efficacy of neoadjuvant chemotherapy, consisting of a taxane, cisplatin, and 5-fluorouracil (5-FU) (the TPF regimen) followed by concurrent chemoradiation, in 2 separately designed and synchronously executed phase 2 trials for stage III and IVA/IVB nasopharyngeal cancer (NPC). METHODS: Patients with newly diagnosed NPC were accrued to 2 trials, 1 for patients with stage III disease and the other for patients with IVA/IVB disease. All patients received TPF (docetaxel 75 mg/m(2), cisplatin 75 mg/m(2), and 5-FU 2500 mg/m(2) every 3 weeks for 3 cycles) followed by cisplatin 40 mg/m(2) per week concurrently with either 3-dimensional conformal radiation therapy or intensity-modulated radiation therapy. RESULTS: From January 2007 to July 2011, 52 eligible patients with stage III NPC and 64 eligible patients with nonmetastatic stage IV NPC were accrued. With a median follow-up of 32.9 months, the 3-year overall survival rates were 94.8% (95% confidence interval [CI], 87.6%-100%) and 90.2% (95% CI, 81.8%-98.6%) for the stage III NPC group and the IVA/IVB NPC group, respectively. The 3-year progression-free survival, distant metastasis-free survival, and local progression-free survival rates were 78.2% (95% CI, 64.6%-91.8%), 90.5% (95% CI, 79.7%-100%), and 93.9%(87.1%-100%), respectively, for patients with stage III NPC and 85.1% (95% CI, 75.1%-95.1%), 88% (95% CI, 78.6%-97.4%), and 100%, respectively, for patients with stage IVA/IVB NPC. The most common severe (grade 3/4) hematologic and nonhematologic adverse events were neutropenia (64 patients; 55.2%) and nausea/vomiting (23 patients; 19.8%). CONCLUSIONS: Neoadjuvant TPF followed by concurrent chemoradiation was well tolerated and produced encouraging outcomes in patients with locally advanced NPC in this hypothesis-generating study. The authors concluded that randomized controlled trials are warranted to definitively confirm this aggressive and potentially efficacious strategy.

An ultrasonographic evaluation of skin thickness in breast cancer patients after postmastectomy radiation therapy.

BACKGROUND: To determine the usefulness of ultrasonography in the assessment of post radiotherapy skin changes in postmastectomy breast cancer patients. METHODS: Patients treated for postmastectomy radiotherapy in National University Hospital (NUH) and Tan Tock Seng Hospital (TTSH), Singapore between January 2004- December 2005 was recruited retrospectively. Ultrasound scan was performed on these Asian patients who had been treated to a total dose of 46-50 Gy with 1 cm bolus placed on the skin. The ultrasound scans were performed blinded to the RTOG scores, and the skin thickness of the individually marked points on the irradiated chest wall was compared to the corresponding points on the non-irradiated breast. RESULTS: The mean total skin thickness inclusive of the epidermis and the dermis of the right irradiated chest wall was 0.1712 mm (± 0.03392 mm) compared with the contra-lateral non-irradiated breast which was 0.1845 mm (± 0.04089 mm; p = 0.007). The left irradiated chest wall had a mean skin thickness of 0.1764 mm (± 0.03184 mm) compared with the right non-irradiated breast which was 0.1835 mm (± 0.02584 mm; p = 0.025). These independent t-tests produced a significant difference of reduced skin thickness on the right irradiated chest wall, p = 0.007 (p < 0.05) and left irradiated chest wall p = 0.025 (p < 0.025) in comparison to the non-irradiated skin thickness investigating chronic skin reactions. Patients with grade 2 acute skin toxicity presented with thinner skin as compared to patients with grade 1 (p = 0.006). CONCLUSIONS: This study has shown that there is a statistically significant difference between the skin thicknesses of the irradiated chest wall and the contra-lateral non-irradiated breast and a predisposition to chronic reactions was found in patients with acute RTOG scoring of grade1 and grade 2.

Controversies and challenges in the current management of nasopharyngeal cancer.

Nasopharyngeal carcinoma is uncommon worldwide, but poses a significant public health burden in endemic regions. Primary treatment for nonmetastatic disease is by radiation therapy, which has evolved from simple 2D-planning techniques to intensity-modulated radiation therapy. The role of systemic therapy has also become more prominent, with concurrent cisplatin-based chemoradiation the current standard of care for locally advanced disease based on multiple Phase III studies. Based on these advances, the prognosis of nasopharyngeal carcinoma appears to have improved significantly over the past two decades. Nevertheless, there are areas of substantial uncertainty and divergent views in the optimal treatment strategy. Distant metastases have become the dominant mode of treatment failure with the excellent local control provided by intensity-modulated radiation therapy. Recent studies have focused on this challenge of treating micrometastases while keeping toxicities manageable. Radiation therapy techniques continue to be refined to maintain consistently high locoregional tumor control while decreasing the probability of acute and late toxicities. This article discusses some of the current issues confronting the multidisciplinary team managing this disease.