Small cell lung cancer ( SCLC ) is one common type of lung cancer in China. No remarkable progress has been made in systemic therapy for SCLC since the 90’ s. However, there are some advances in radiotherapy ( RT) for SCLC, which make it possible to improve treatment outcomes of SCLC. Those advances are mainly made in thoracic RT and prophylactic cranial irradiation for extensive?stage SCLC, radiation dose and technology of thoracic RT for limited?stage SCLC, and significance of prophylactic cranial irradiation for early?stage SCLC. The paper reviews the research advances in the East and West to provide some help and references for readers.

As a newly identified T helper cell subset, Th9 plays an important role in anti-tumor immunity. Th9 can be differentiated from CD4+T cells that have been induced by TGF-beta and IL-4. In addition, other CD4+T helper cell subsets can be developed to Th9 cell in particular situations, thereby showing its plasticity. Results of animal experiments have indicated that Th9 inhibits tumor growth and plays a significant role in anti-tumor immunity by secreting related cytokines such as IL-9. A few cytokines and molecules can regu-late the differentiation and development of Th9 cells in different signaling pathways. This review will focus on the production, anti-tu-mor immunity, related mechanism, and signaling pathways of Th9 cells, thereby providing a new field of vision and idea for anti-tumor therapy in the future.

Chemotherapy, molecular targeted therapy, and hormonal therapy are essential components of medical oncology. Al-though cancer patients significantly benefit from the emergence of various new anticancer drugs, none of these treatments can directly address drug resistance. Radiation therapy is one of the three conventional cancer treatment methods. Nearly two-thirds of cancer pa-tients accept radiation therapy during treatment. However, radiation resistance is a significant barrier affecting the therapeutic effect of this procedure. Epithelial–mesenchymal transition (EMT) is a biologic process that enables a polarized epithelial cell to undergo multi-ple biochemical changes. These changes enable the cell to assume the functions of a mesenchymal cell phenotype. These functions have been extensively studied and are related to embryogenesis, tumor invasiveness, and metastasis. In recent years, increasing evidence sug-gests that EMT is closely linked with tumor treatment resistance. The study of the relation between EMT and tumor treatment resistance is expected to contribute to the prevention of drug resistance and radiation resistance and thus improve treatment efficacy to provide benefit to cancer patients. This article explores this issue.

Although it has been frequently used to treat thoraxic tumors,radiation induced lung injury (RILI) is the major factor of dose limitation in thoracic radiotherapy.Amount of endogenous and exogenous reactive oxygen / nitrogen species (ROS/RNOS) could be generated in the radiated organisms and further cause molecular damage of DNA,protein and membrane lipids,which results in celluar structure damage,dysfunction and RILI.In addition,a series of cytokines could also induce chronic oxidative stresses that contribute to increases in cell membrane permeability,tissue edema and extracellular matrix proteins accumulation and even further result in pulmonary fibrosis.Oxidative stress theory offers new clues and strategies for further understanding the mechanism of RILI,and some anti-oxidative stress drugs may have potential clincial application in RILI treatment.

Radiation?induced heart disease ( RIHD) is a common type of radiation?induced damages in chest radiotherapy. There are no obvious short?term symptoms in patients with RIHD. However, RIHD causes irreversible permanent damages to the heart over time, which undermines the quality of life. Patients with severe RIHD even have a risk of death from myocardial infarction caused by coronary atherosclerosis. This paper summarizes the research advances in epidemiology, diagnosis, mechanisms of radiation?induced injury in various parts of the heart, radiotherapy techniques, and treatment. Reduction in radiation range and dose, early diagnosis, and early treatment are recommended for patients to reduce heart injury and improve the quality of life.

Objective To investigate the efficacy,toxicity and cosmetic outcome of short-course radiotherapy with concomitant tumor bed boost after breast-conserving surgery for early stage breast cancer.Methods A total of 306 patients with T1-2 N0-1 M0 breast cancer after breast-conserving surgery were included.160 patients received whole-breast radiation to 45 Gy in 25 fractions followed by tumor bed boost of 14 Gy in 7 fractions (C group).146 patients received whole-breast radiation to 46 Gy in 23 fractions with concomitant tumor bed boost to 60 Gy in 23 fractions (S group).Kaplan-Meier method was used to calculate the local recurrence and overall survival rates and the differences were compared by Logrank test.Chi-square test was used to compared the differences of the clinical characteristics,toxicity and cosmetic outcome between the two groups.Results The follow-up rate was 100％.After a median follow up of 26 months,the 1-,2-and 3-year overall survival rates were 100％.No patient developed local recurrence.In C and S group,the incidence of grade 1 acute skin toxicity was 46.9％ and 45.1％ (x2 =0.73,P =0.695),grade 2was 16.3％ and 13.7％ (x2 =0.73,P =0.695).Grade 1 late skin and subcutaneous tissue toxicity developed in 16.9％ and 17.1％ of patients in C and S group (x2 =0.00,P =0.954).Grade 1 neutropenia occurred in 11.9％ and 13.7％ of patients in C and S group (x2 =0.23,P =0.633).In C and S group,66.2％ and 65.5％ of patients had excellent and good cosmetic outcome (x2 =0.01,P =0.927).Conclusions Short-course radiotherapy with concomitant tumor bed boost provides similar results to conventional radiotherapy in local control,toxicity and cosmetic outcome.Long-term follow up is warranted to confirm this finding.

As a DNA damage sensor,poly (ADP-ribose) polymerase (PARP) is involved in a wide variety of cellular activities,such as DNA damage repair.PARP inhibitors regulate a series of cellular activities by inhibiting PARP function,which have become a focus of current research.Recently,several in vivo and in vitro studies showed that PARP inhibitors combined with radiotherapy effectively enhanced the efficacy of radiotherapy.This paper reviews the research advances in the mechanisms of action of PARP inhibitors and their combination with radiotherapy.

Objective To explore the reasonable radiotherapy range by analyzing the patterns and characteristics of intra-thoracic lymph node metastasis in small cell lung cancer (SCLC).Methods One hundred and fifty patients with limited-stage SCLC who received radical resection of primary tumor and systemic intra-thoracic lymph node dissection were included in the study.All the lymph nodes in each area were recorded and examined pathologically to analyze the patterns and characteristics of intra-thoracic lymph node metastasis.Results A total of 2372 lymph nodes were found in 631 areas,and a total of 413 positive lymph nodes (17.4％) were found in 188 lymph node areas (29.8％ ).Intra-thoracic lymph node metastasis were found in 88 patients,with a positive rate of 58.7％.The frequencies of metastasis in the area 11,10,7,5,4 were much higher than those in the other areas,and central located lesions and the higher T-stage lung tumors were more likely to develop intra-thoracic lymph node metastasis (x2 =15.32,39.72;P =0.000,0.000,respectively).Tumors located in the right upper lobe and right middle/lower lobe had a higher tendency of metastasis to the areas 4,7,10 and 4,7,10,11,respectively.Tumors located in the left upper lobe and left lower lobe had a higher tendency of metastasis to the areas 4,5,6,10 and 4,7,9,10,11,respectively.Mediastinal lymph node metastasis (N2 ) were found in 72 patients,among whom 29 patients (40.3％ ) had skipping N2 metastasis without hilar metastasis.Tumors located in the upper lobe had a tendency of skipping metastasis to the upper mediastinum,while tumors located in the middle/lower lobe had a tendency of skipping metastasis to the upper and lower mediastinum.Conclusions The lymph node metastases in SCLC follow the lymphatic drainage routes,that is,from intrapulmonary to the hilar and then to the mediastinum,but with some skipping metastases.Tumors located in different lobes have different high risk lymph node areas for metastasis,and elective irradiation to these lymph node areas maybe increase radiotherapy gain ratio in SCLC.

Objective To evaluate the clinical efficacy and toxicities of radical intensity-modulated radiotherapy (IMRT) combined with reduction in dose of prophylactic irradiation in the treatment of stage Ⅲ small cell lung cancer (SCLC).Methods A retrospective analysis was performed on the clinical data of 40 patients with stage Ⅲ SCLC who were admitted from January 2010 to August 2012.The prescribed dose was 60 Gy in 30 fractions to the primary gross tumor volume and was 54 Gy in 30 fractions to the planning target volume.All patients received induction chemotherapy,31 patients received adjuvant chemotherapy,and 22 patients received concurrent chemoradiotherapy;the platinum-based chemotherapy combined with etoposide or teniposide was adopted.Prophylactic cranial irradiation (25 Gy in 10 fractions) was administered to 17 patients.The short-term tumor response was evaluated by RECIST 1.0,and radiation-related toxicities were assessed by CTCAE 4.0.Overall survival (OS),local recurrence-free survival (LRFS),and progression-free survival (PFS) were calculated by Kaplan-Meier method.Results The short-term tumor response rate was 98％.The follow-up rate was 100％.Twenty-two patients were followed up for at least 2 years.The 1-and 2-year OS rates were 84％ and 48％,respectively; the LRFS rates were 89％ and 85％,respectively; the PFS rates were 61％ and 41％,respectively.Grade 0-1 radiation-related pneumonia was observed in 65％(26/40) of all patients,grade 2 in 25％ (10/40),grade 3 in 5％ (2/40),and grade 5 in 5％ (2/40).Grade 0-1 radiation-related esophagitis was observed in 53％ (21/40) of all patients,grade 2 in 43％ (17/40),and grade 3 in 5 ％ (2/40).Conclusions Preliminary results from this study suggested that IMRT combined with reduction in dose of prophylactic irradiation is safe and effective in patients with stage Ⅲ SCLC and is worth further evaluation in a large,prospective,randomized study.