[Stereotactic body radiation therapy for patients with lung and liver oligometastases from colorectal cancer: a phase Ⅱ trial]

Objective: To explore the safety and effectiveness of stereotactic body radiation therapy (SBRT) for oligometastases from colorectal cancer (CRC). Methods: This is a prospective, single-arm phase Ⅱ trial. Patients who had histologically proven CRC, 1 to 5 detectable liver or lung metastatic lesions with maximum diameter of any metastases ≤5 cm were eligible. SBRT was delivered to all lesions. The primary endpoint was 3-year local control (LC). The secondary endpoints were treatment-related acute toxicities of grade 3 and above, 1-year and 3-year overall survival (OS) and progression free survival (PFS). Survival analysis was performed using the Kaplan-Meier method and Log rank test. Results: Petients from 2016 to 2019 who were treated in Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College. Forty-eight patients with 60 lesions were enrolled, including 37 liver lesions and 23 lung lesions. Forty-six patients had 1 or 2 lesions, with median diameter of 1.3 cm, the median biologically effective dose (BED(10)) was 100.0 Gy. The median follow-up was 19.5 months for all lesions. Twenty-five lesions developed local failure, the median local progression free survival was 15 months. The 1-year LC, OS and PFS was 70.2% (95% CI, 63.7%~76.7%), 89.0% (95% CI, 84.3%~93.7%) and 40.4% (95%CI, 33.0%~47.8%). The univariate analysis revealed that planning target volume (PTV) and total dose were independent prognostic factors of LC (P<0.05). For liver and lung lesions, the 1-year LC, OS and PFS was 58.7% and 89.4% (P=0.015), 89.3% and 86.5% (P=0.732), 30.5% and 65.6% (P=0.024), respectively. No patients developed acute toxicity of grade 3 and above. Conclusion: SBRT is safe and effective treatment method for oligometastases from CRC under precise respiratory motion management and robust quality assurance.

Long-Term Outcome of Centrally Located Hepatocellular Carcinomas Treated by Radical Resection Combined With Intraoperative Electron Radiotherapy (IOERT)

Purpose

To explore the feasibility and safety of centrally located hepatocellular carcinoma (CL-HCC) treated by narrow-margin resection combined with intraoperative electron radiotherapy (IOERT).

Methods and Materials

From November 2009 to November 2016, 37 consecutive patients were treated with IOERT as adjuvant treatment during narrow-margin resection for CL-HCC. Long-term outcomes, adverse events for surgery, and acute and chronic toxicities were analyzed.

Results

The median follow-up was 57.82 months (range, 3.75-111.41 months). A total dose of 15 Gy (range 12 to 17Gy) (prescribed at the 90% isodose) was delivered with a 0.9cm (range 0.8-1.2 cm) median treatment depth targeting the narrow-margin. The 1-year, 3-year and 5-year OS rates were 91.39%, 88.34% and 88.34%, respectively. The 1-year, 3-year and 5-year DFS rates were 80.81%, 68.59% and 54.17%, respectively. In the univariate analysis, none of the treatment characteristics were predictive of overall survival. Fifteen (40.5%) patients suffered from a recurrence event. No patient had marginal recurrence. The 1-year, 3-year and 5-year intrahepatic recurrence rates were 19.75%, 25.92% and 39.58%, respectively. The 1-year, 3-year and 5-year extrahepatic recurrence rates were 2.7%, 5.95% and 9.87%, respectively. There was no 30-day surgical-related death. Three patients had grade 4, and 28 patients had grade 3 alanine aminotransferase (ALT) levels, and seven patients had grade 4, and 30 patients had grade 3 aspartate transaminase (AST) levels. All of them returned to normal within four months. There was no acute radiation-induced liver injury during follow-up. There were no acute or chronic toxicities associated with IOERT.

Conclusion

IOERT for narrow-margin CL-HCC may achieve good long-term survival outcomes, without significantly increasing acute and chronic toxicities. An IOERT dose of 15Gy may be the safest and most feasible. IOERT might be considered as an adjuvant therapy for CL-HCC patients with a narrow-margin.

The role of metal ions in the behavior of bovine serum albumin molecules under physiological environment

Metal ions released from metallic implants can affect the conformation and structural stability of proteins in biological fluids, which eventually affects the biocompatibility of implants. The present study aimed at understanding the interactions between the metal ions (Mn²⁺, Fe²⁺, Fe³⁺, Co²⁺, Cu²⁺, and Zn²⁺) and bovine serum albumin (BSA) molecules in physiological context. The structural information of BSA molecules and the microenvironment of functional groups were investigated using UV, Raman, and circular dichroism spectroscopy. The results revealed that addition of Fe³⁺, Fe²⁺, and Cu²⁺ ions alters the tertiary structure of BSA molecules and exposes the aromatic heterocyclic hydrophobic group of BSA amino acid residues. The addition of Fe³⁺ and Cu²⁺ ions results in increased viscosity and decreased intensity of the water peak in the BSA solution. Furthermore, Fe³⁺ and Cu²⁺ ions evidently promote the α-helix to β-sheet transformation of BSA molecules due to decreased disulfide bond stability. Tryptophan residues of BSA and metal ions containing BSA (Me⁺/BSA) solutions were found to be in a hydrophilic environment. Moreover, the addition of metal ions to BSA results in several of tyrosine residues acting as hydrogen-bond donors. Coomassie brilliant blue staining revealed that the addition of Cu²⁺ ions promotes the aggregation of BSA molecules. The findings of this study will be helpful for evaluating the biocompatibility of metallic implants.

[Help-seeking efficacy and the intention of social assistance among medical care personnel during the major public health events]

Objective: To explore the help seeking efficacy and social assistance willingness of medical staff during major public health events, so as to provide basis for improving the psychological resources and service quality of medical staff and further optimizing the prevention and treatment policies. Methods: In February 2020, a convenient sampling method was used to conduct an online questionnaire survey on medical staff in Henan Province, and a total of 2136 questionnaires were collected. Among them, there were 1940 valid questionnaires, and the effective recovery rate was 90.82%. The questionnaire of help seeking efficacy and willingness to social assistance under epidemic situation was used to investigate the help seeking efficacy and willingness of medical staff. The frequency and rate (%) were used to analyze the overall situation of medical staff's help seeking efficacy and social assistance willingness. The differences among different demographic variables were tested by χ(2) test. Results: Among the 1940 medical and nursing staff, 18.81% (365/1940) did not know how to obtain appropriate psychological assistance. Compared with the low age group, the medical staff in the high age group had the ability of information query, the ability to occupy knowledge resources, the ability to distinguish rumors and facts and the sense of efficacy of obtaining appropriate medical help, and the difference was statistically significant (P<0.05) . The willingness of medical and nursing staff to actively cooperate with the government, maintain social stability and volunteer work were 99.43% (1929/1940) , 98.81% (1917/1940) and 97.11% (1884/1940) . Conclusion: The medical staff had a higher sense of help seeking efficacy and willingness to social assistance. It is necessary to further strengthen the resource support of psychological, social and humanistic care for medical staff.

[Proportion and rate: connotation and understanding route]

Proportion and rate have multiple and overlapping meanings, which blur their concepts. Based on the existence of the states and the occurrence of the events and their measuring process, we first put forward the concept of "cumulative number of states in point time". Considering the general meaning of "rate" in mathematics and the units of the elements in indexes, this paper puts forward the concept of "the change of cumulative number of states in point time", which is equal to the commonly acknowledged concept "number of incident event within observation period" or "absolute rate", and further constructs relative rate and proportion. Proportions can be classified into three types: time-point (or rate-type) constitutional proportion, time-period incidence proportion and their synthesis, time-period constitutional proportion. The essential difference between relative rate and time-period proportions is whether the observation period is regarded as a one-unit-length fixed period which would be further moved to the description of the indexes. Furthermore, the sources populations of relative rate and proportions are exclusively those at the beginning of the observation period. Thus, we established a unified identification route about ratios, proportions, and rates, the basic indicators of categorical data in populations. These are applicable to both fixed and dynamic populations. The paper aims to clarify the connotation of the indexes and the feasible understanding route and provide some reference for the population researchers.

[A new classification of maxillary defect and simultaneous accurate reconstruction]

Objective: To select the preferred flaps for the reconstruction of different maxillary defects and to propose a new classification of maxillary defects. Methods: A total of 219 patients (136 males and 83 females) underwent the simultaneous reconstruction of maxillary defects in the Beijing Tongren Hospital, Capital Medical University, between January 2005 and December 2018 were reviewed. Age ranged from 16 to 78 years. Based on the proposed new classification of the maxillary defects, 22 patients with class Ⅰ defects (inferior maxillectomy), 44 patients with class Ⅱ defects (supperior maxillectomy), 132 patients with class Ⅲ defects (total maxillectomy) and 21 patients with class Ⅳ defects (extensive maxillectomy) were enrolled. Survival rate, functional and aesthetic outcomes of flaps were evaluated. Survival analysis was performed in 169 patients with malignant tumor, Kaplan-Meier method was used to calculate the survival rate, and Log-rank method was used to compare the difference of survival rate in each group. Results: A total of 234 repairs for maxillary defects were performed in 219 patients. Fibula flaps were used in 4/13 of class Ⅰ defects; temporal muscle flaps (11/24, 45.8%) and anterolateral thigh flaps (6/24, 25.0%) used in class Ⅱ defects; temporal muscle flaps (71/128, 55.5%), anterolateral thigh flaps (6/24, 25.0%) and fibula flaps (12/128, 9.4%) used in class Ⅲ defects; and anterolateral thigh flaps (8/20, 40.0%) and rectus abdominis flaps (8/20, 40.0%) used in class Ⅳ defects. The success rate of local pedicled flaps was 95.6% (109/114) and that of free flaps was 95.8% (115/120). Thrombosis(10/234,4.3%) was a main reason for repair failure. Among the followed-up 88 patients, swallowing and speech functions recovered, 82 (93.2%) of them were satisfied with appearance, and 75 (85.2%) were satisfied with visual field. The 3-year and 5-year overall survival rates were 66.5% and 63.6%, and the 3-year and 5-year disease-free survival rates were 57.1% and 46.2%, respectively, in the 169 patients with malignant tumors. Conclusion: A new classification of maxillary defects is proposed, on which suitable flaps are selected to offer patients good functional and aesthetic outcomes and high quality of life.

Survival benefit of surgery in patients with clinical T4 esophageal cancer who achieved complete or partial response after neoadjuvant chemoradiotherapy or radiotherapy

Objective:

This study aimed to determine the long-term survival of patients with cT4 esophageal cancer (EC) and whether neoadjuvant chemoradiotherapy/radiotherapy plus surgery (nCRT/RT + S) is superior to definitive CRT(dCRT)/RT in terms of survival in cT4 EC downstaged after nCRT/RT.

Summary background data:

Treatment options for cT4 EC include dCRT/RT and nCRT/RT + S, but it is not clear whether the latter provides survival benefit in patients downstaged after nCRT/RT.

Methods:

From 2002 to 2017, 726 patients with cT4 esophageal squamous cell carcinoma (ESCC) were retrospectively analyzed. Patients achieving clinical complete response (cCR) or partial response (PR) after 4-week RT (median dose, 40.7 Gy) and considered fit for surgery were offered esophagectomy. Of the 726 patients, 308 (42.4%) achieved cCR/PR, while 74 patients received subsequent surgery (nCRT/RT + S group), 234 patients received dCRT/RT.

Results:

Median follow-up was 58 months. The 3-year overall survival (OS) and progression-free survival (PFS) rates for all patients were 33.3% and 35.6%, respectively. The corresponding OS and PFS rates were 54.8% and 48.5% in the nCRT/RT + S group versus 30.0% and 22.1% in the dCRT/RT group (both p < 0.0001). After adjusting the confounding variables with inverse probability of treatment weighting, the adjusted 3-year OS rates were 50.4% in the nCRT/RT + S group versus 50.8% in the dCRT/RT group (p = 0.15). However, the adjusted 3-year PFS rates were significantly different between the two groups (49.0% and versus 38.3%, p = 0.004). Postoperative complications occurred in 18 (24.3%) patients.

Conclusion:

The long-term survival of cT4 ESCC was improved after the use of three-dimensional CRT. In cT4, EC responded to nCRT/RT, surgery improves PFS but not OS.

[The expression of clock gene CLOCK and its clinical significance in nasopharyngeal carcinoma]

Objective: To explore the relationship between expression levels of CLOCK mRNA and protein and the clinical characteristics of patients with nasopharyngeal carcinoma. Methods: The frozen tissue specimens from 33 patients with nasopharyngeal carcinoma in the Affiliated Tumor Hospital of Guizhou Medical University from 2018 to 2019 were collected. Seventeen cases of tissue specimens from patients with nasopharyngeal chronic inflammation in the Affiliated Hospital of Guizhou Medical University in 2019 were collected. From 2008 to 2014, 68 cases of formalin-fixed paraffin-embedding (FFPE) nasopharyngeal carcinoma tissue and 37 cases of FFPE nasopharyngeal chronic inflammation tissue were collected from the Affiliated Tumor Hospital of Guizhou Medical University. Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blot (WB) were used to detect the mRNA and protein expression levels of CLOCK. The nasopharyngeal carcinoma cells including CNE1, CNE2, 5-8F and the normal nasopharyngeal epithelial cell NP69 were cultured. qRT-PCR was used to detect the expression level of CLOCK mRNA in each cell line at the time points of ZT2, ZT6, ZT10, ZT14, ZT18 and ZT22. The cosine method was used to fit the rhythm of CLOCK gene in nasopharyngeal carcinoma. The protein expression of CLOCK protein was detected by using immunohistochemical method in 68 cases of nasopharyngeal carcinoma and 37 cases of nasopharyngeal chronic inflammation tissue. Survival was analyzed by Kaplan-Meier method and Log rank test, and the influencing factors was analyzed by Cox regression model. Results: The expression levels of CLOCK mRNA in CNE1, CNE2 and 5-8F cells (0.63±0.07, 0.91±0.02 and 0.33±0.04, respectively) were lower than that in NP69 cell (1.00±0.00, P<0.05). The expression levels of CLOCK protein in CNE1, CNE2 and 5-8F cells (0.79±0.06, 0.57±0.05 and 0.74±0.10, respectively) were lower than that of NP69 cells (1.00±0.00, P<0.05). The expressions of CLOCK mRNA in nasopharyngeal carcinoma cells including CEN1, CNE2, 5-8F and normal nasopharyngeal epithelial cell NP69 were different at different time points, with temporal fluctuations. The fluctuation periods of CLOCK mRNA in CNE1, CNE2, 5-8F, and NP69 cells were 16, 14, 22 and 24 hours, respectively. The peak and trough times were ZT10: 40 and ZT18: 40, ZT10 and ZT3, ZT14: 30 and ZT3: 30, ZT12: 39 and ZT0: 39, respectively. CLOCK mRNA and protein expression levels in nasopharyngeal carcinoma tissues (0.37±0.20 and 0.20±0.26, respectively) were lower than those in nasopharyngeal chronic inflammation tissues (1.00±0.00 and 0.51±0.41, respectively, P<0.05). The 1, 3, and 5-year survival rates of patients in the CLOCK protein high expression group (CLOCK protein expression level ≥ 0.178) were 96.2%, 92.1%, and 80.1%, respectively, which were higher than those in the low expression group (CLOCK protein expression level <0.178, 92.9% , 78.6% and 57.1%, respectively, P=0.009). The 1, 3, and 5-year progression-free survival (PFS) rates of patients in the CLOCK protein high expression group were 96.2%, 87.8%, and 87.7%, respectively, which were higher than those in the low expression group (92.7%, 82.2%, and 70.8%, respectively, P=0.105). Compared with the low-expression group (100.0%, 96.9%, and 90.0%, respectively), the 1, 3, and 5-year recurrence-free survival rates of patients in the CLOCK protein high expression group (100.0%, 95.7%, and 95.7%, respectively) were not statistically significant (P=0.514). Compared with the low-expression group (92.7%, 82.2%, and 79.3%), the 1, 3, and 5-year survival rates without metastasis in the CLOCK protein high expression group (96.2%, 92.0%, and 92.0%, respectively) were not statistically significant (P=0.136). CLOCK protein expression and T stage were independent prognostic factors of overall survival (P<0.05). Conclusions: The expression of CLCOK is downregulated in the nasopharyngeal carcinoma cell and nasopharyngeal carcinoma tissues. Clock gene CLOCK is rhythmically expressed in the nasopharyngeal carcinoma cells and normal nasopharyngeal epithelial cells. Compared with normal nasopharyngeal epithelial cells, the fluctuation period of CLOCK in nasopharyngeal carcinoma cells is shortened. The overall survival of patients in the CLOCK protein high expression group is better than that of low expression group. The expression of CLOCK protein is an independent influencing factor for overall survival. CLOCK gene may be a potential tumor suppressor gene in the nasopharyngeal carcinoma.

Effect of postmastectomy radiotherapy on pT1-2N1 breast cancer patients with different molecular subtypes

Objective

To clarify the effect of postmastectomy radiotherapy (PMRT) on pT_1-2N₁ breast cancer patients with different molecular subtypes.

Methods

We retrospectively analyzed the data of 5442 patients with pT_1-2N₁ breast cancer treated using modified radical mastectomy in 11 hospitals in China. Univariate, multivariate, and propensity score matching (PSM) analyses were used to evaluate the effect of PMRT on locoregional recurrence (LRR).

Results

With a median follow-up duration of 63.8 months, the 5-year LRR rates were 4.0% and 7.7% among patients treated with and without PMRT, respectively (p < 0.001). PMRT was independently associated with reduced LRR after adjustments for confounders (p < 0.001). After grouping the patients according to the molecular subtype of cancer and conducting PSM, we found that the 5-year LRR rates among patients treated with and without PMRT (in that order) were as follows: luminal HER2-negative cancer, 1.9% and 6.5% (p < 0.001); luminal HER2-positive cancer, 3.8% and 13.7% (p = 0.041); HER2-overexpressing cancer, 10.2% and 15.5% (p = 0.236); and triple-negative cancer, 4.6% and 15.9% (p = 0.002). Among patients with HER2-overexpressing and triple-negative cancers, the LRR hazard rate displayed a dominant early peak, and was extremely low after 5 years. However, patients with luminal cancer continued to have a long-lasting high annual LRR hazard rate during follow-up.

Conclusion

PMRT significantly reduced the LRR risk in patients with pT_1-2N₁ luminal and triple-negative breast cancers, but had no effect on the LRR risk in patients with HER2-overexpressing cancer. Patients with different molecular subtypes displayed different annual LRR patterns, and the late recurrence of the luminal subtype suggests the necessity of long-term follow-up to evaluate the efficacy of PMRT.

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PMRT reduces LRR of pT_1-2N₁ luminal and triple-negative breast cancers.

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PMRT has no effect on the LRR of HER2-overexpressing breast cancer.

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Different molecular subtypes display different annual LRR patterns.

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Late LRR beyond 5 years is observed in luminal breast cancers.

[Safety analysis of definitive surgery for chronic radiation intestinal injury]

Objective: To investigate the safety of definitive surgery for chronic radiation intestinal injury. Methods: A descriptive case series study was performed. Clinical data of 105 patients who were diagnosed as chronic radiation intestinal injury, had complete data and received definitive surgery (the radiation-induced intestinal segment and digestive tract reconstruction) at Department of Gastrointestinal Surgery of Beijing Tsinghua Changgung Hospital from June 2016 to May 2020 were retrospectively analyzed. There were 30 males (28.6%) and 75 females (71.4%) with the median age of 58 years (P25, P75: 52, 64 years). Patients who had tumor recurrence or refused surgical treatment were excluded. According to the preoperative evaluation and clinical manifestations, to select the resection range. Outcome parameters: (1) preoperative evaluation (nutrition risk assessment and status of obstruction or fistula); (2) clinical manifestations and treatment strategies; (3) details of surgical parameters; (4) postoperative complications, and Clavien-Dindo classification III to V was defined as main moderate-severe complication. Results: (1) Preoperative evaluation: Eighty-eight patients (83.8%) developed symptoms of chronic radiation intestinal injury more than 1 year after the end of radiotherapy. Ninety-eight patients (93.3%) had preoperative NRS-2002 score ≥3, 74 patients (70.5%) received preoperative parenteral nutritional support, and the median time of nutritional support was 10.5 (7.0, 16.0) days. Sixteen patients (15.2%) received small intestinal decompression tube implantation due to severe obstruction. (2) Clinical manifestations and treatment strategies: Among 105 patients, 87 (82.9%) presented with obstruction and received definitive resection of the radiation-induced intestinal segment plus one-stage digestive tract reconstruction; 18 (17.1%) presented with intestinal fistula and all of them received definitive resection of the radiation-induced intestinal segment, intestinal fistula plus one-stage digestive tract reconstruction. Among above 18 patients with fistula, 3 patients with ileorectal stump fistula received pedicled pelvic closure of greater omentum at the same time; 4 patients had ileal vesical fistula, of whom 2 patients received cystectomy and bladder repair due to preoperative nephrostomy decompression, and the other 2 patients received transection of the small intestine proximal and distal to the fistula and anastomosis of the intestinal loop without fistula resection, intestinal fistula or bladder fistula repair. (3) The details of surgical parameters: Median operative time and intraoperative blood loss was 230 (180, 300) minutes and 50 (20, 50) ml respectively. Ninety-two patients (92/105, 87.6%) underwent ileocolonic anastomosis, and anastomosis on the hepatic flexure or splenic flexure colon were performed in 88 (83.8%) and 4 (3.8%) patients respectively. Ileoileal anastomosis was performed in 13 patients (12.4%). The anastomotic site of 92 patients (87.6%) was strictly located in the contralateral quadrant of the radiation field, and the anastomotic site of 13 patients (12.4%) was far from the radiation field. Nine patients (8.6%) had more than one anastomosis, 5 patients (4.8%) had less than 180 cm of residual small intestine, 7 patients (6.7%) underwent retrograde intestinal permutation, 4 patients (3.8%) underwent abdominal wall reconstruction surgery due to abdominal wall defects, and 87 patients (82.9%) had severe abdominal pelvic adhesions (grade 3-4 adhesions). Intraoperative complications occurred in 3 patients (2.9%), which were found in time and handled properly. The median postoperative hospital stay was 13.0 (12.0, 24.5) days, and all the patients had resumed oral feeding upon discharge. (4) Postoperative complications: Fourteen patients (13.3%) had 18 major complications (grade III to V). The incidence of postoperative anastomotic leakage was 5.7% (6/105), and the incidence of anastomotic leakage for ileocolon anastomosis and ileoileal anastomosis was 2.2% (2/92) and 4/13, respectively (χ(2)=17.29, P<0.001). The incidence of postoperative anastomotic leakage of intestinal fistula and intestinal obstruction was 3/18 and 3.4% (3/87), respectively (χ(2)=4.84, P=0.028). The mortality at 30 days after operation was 1.0% (1/105), after abdominal infection and septic shock caused by postoperative anastomotic leakage resulting in multiple organ failure. Conclusion: For chronic radiation intestinal injury patients with obstruction or fistula, definitive surgical treatment is feasible and safe with acceptable major complications.

POstmastectomy radioThErapy in Node-posiTive breast cancer with or without Internal mAmmary nodaL irradiation (POTENTIAL): a study protocol for a multicenter prospective phase III randomized controlled trial

BACKGROUND

Various randomized trials have demonstrated that postmastectomy radiotherapy (RT) to the chest wall and comprehensive regional nodal areas improves survival in patients with axillary node-positive breast cancer. Controversy exists as to whether the internal mammary node (IMN) region is an essential component of regional nodal irradiation. Available data on the survival benefit of IMN irradiation (IMNI) are conflicting. The patient populations enrolled in previous studies were heterogeneous and most studies were conducted before modern systemic treatment and three-dimensional (3D) radiotherapy (RT) techniques were introduced. This study aims to assess the efficacy and safety of IMNI in the context of modern systemic treatment and computed tomography (CT)-based RT planning techniques.

METHODS

POTENTIAL is a prospective, multicenter, open-label, parallel, phase III, randomized controlled trial investigating whether IMNI improves disease-free survival (DFS) in high-risk breast cancer with positive axillary nodes (pN+) after mastectomy. A total of 1800 patients will be randomly assigned in a 1:1 ratio to receive IMNI or not. All patients are required to receive ≥ six cycles of anthracycline and/or taxane-based chemotherapy. Randomization will be stratified by institution, tumor location (medial/central vs. other quadrants), the number of positive axillary nodes (1-3 vs. 4-9 vs. ≥10), and neoadjuvant chemotherapy (yes vs. no). Treatment will be delivered with CT-based 3D RT techniques, including 3D conformal RT, intensity-modulated RT, or volumetric modulated arc therapy. The prescribed dose is 50 Gy in 25 fractions or 43.5 Gy in 15 fractions. Tiered RT quality assurance is required. After RT, patients will be followed up at regular intervals. Oncological and toxilogical outcomes, especially cardiac toxicities, will be assessed.

DISCUSSION

This trial design is intended to overcome the limitations of previous prospective studies by recruiting patients with pN+ breast cancer, using DFS as the primary endpoint, and prospectively assessing cardiac toxicities and requiring RT quality assurance. The results of this study will provide high-level evidence for elective IMNI in patients with breast cancer after mastectomy.

TRIAL REGISTRATION

ClinicalTrails.gov , NCT04320979 . Registered 25 Match 2020, https://clinicaltrials.gov/ct2/show/NCT04320979.

Postoperative Chemoradiotherapy With Capecitabine and Oxaliplatin vs Capecitabine for Stage II to III Rectal Cancer: A Randomized Clinical Trial

IMPORTANCE

Several studies have explored the efficacy and toxic effects of concurrent 5-fluorouracil (5-FU)- or capecitabine-based chemoradiotherapy (CRT) with or without oxaliplatin in the neoadjuvant setting. Addition of oxaliplatin to 5-FU or capecitabine elicited similar outcomes but with significantly increased toxic effects; however, there is a need for randomized clinical trials comparing 2 CRT regimens for patients receiving CRT in the adjuvant setting.

OBJECTIVE

To explore the efficacy and toxic effects of oxaliplatin combined with postoperative concurrent capecitabine and radiotherapy (RT) for pathological stage II and III rectal cancer.

DESIGN, SETTING, AND PARTICIPANTS

This multicenter randomized clinical trial enrolled patients from 7 centers in China between April 1, 2008, and December 30, 2015. Patients with pathologically confirmed stage II and III rectal cancer were randomized (1:1) to receive concurrent CRT with capecitabine or capecitabine plus oxaliplatin. Analysis was conducted from December 31, 2019, to March 15, 2020.

INTERVENTIONS

RT comprised 45 to 50 Gy in 25 fractions of 1.8 to 2.0 Gy over 5 weeks. In the capecitabine with RT group, concurrent chemotherapy included 2 cycles of capecitabine (1600 mg/m2) on days 1 to 14 and 22 to 35. The capecitabine and oxaliplatin with RT group received identical postoperative RT to that in the capecitabine with RT group combined with capecitabine (1300 mg/m2) on days 1 to 14 and 22 to 35 and a 2-hour infusion of oxaliplatin (60 mg/m2) on weeks 1, 2, 4, and 5. Patients in both groups received adjuvant chemotherapy (capecitabine or fluorouracil and oxaliplatin) after CRT.

MAIN OUTCOMES AND MEASURES

The primary end point was 3-year disease-free survival (DFS).

RESULTS

A total of 589 patients (median [IQR] age, 55 [47-52] years; 375 [63.7%] men and 214 [36.3%] women) were enrolled, including 294 patients randomized to the capecitabine with RT group and 295 patients randomized to the capecitabine and oxaliplatin with RT group. Median (IQR) follow-up was 68 (45-96) months. Most patients had stage III disease (574 patients [75.9%]). Three-year DFS was 76.3% for the capecitabine with RT group and 74.1% for the capecitabine and oxaliplatin with RT group, and 5-year DFS was 72.0% for the capecitabine with RT group and 71.1% for the capecitabine and oxaliplatin with RT group (hazard ratio [HR], 1.07; 95% CI, 0.79-1.44; P = .68). There was no significant difference between groups in overall survival (HR, 0.93; 95% CI, 0.64-1.34; P = .70) or local recurrence (HR, 0.61; 95% CI, 0.31-1.22; P = .16). More grade 3 and 4 acute toxic effects were observed in the capecitabine and oxaliplatin with RT group than in the capecitabine with RT group (114 patients [38.6%] vs 84 patients [28.6%]; P = .01).

CONCLUSIONS AND RELEVANCE

This randomized clinical trial found that addition of oxaliplatin to capecitabine-based postoperative CRT did not improve the efficacy of treatment but increased the risk of severe acute toxic effects. This finding highlights the basic role of postoperative capecitabine with RT for patients with locally advanced rectal cancer.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT00714077.

[Effects of SGLT2i on 24-hour ambulatory blood pressure in patients with type 2 diabetes complicating hypertension: a meta-analysis]

Objective: To analyze the effects of different types of sodium-glucose cotransporter 2 inhibitors (SGLT2i) on 24-hour ambulatory blood pressure in patients with type 2 diabetes mellitus and hypertension. Method: In this meta-analysis, we searched for randomized controlled trials on the effect of SGLT2i on 24-hour ambulatory blood pressure in patients with type 2 diabetes and hypertension. Three databases, namely PubMed, Web of Science and Cochrane Library, were searched. The search was organized on the concept of 3 conceptual groups: the first group contained terms used to describe SGLT2i, the second group contained terms related to blood pressure, and the third group contained terms used to describe randomized controlled trials. The search time was from the establishment of the database to December 2020. The inclusion and exclusion criteria were formulated in accordance with the requirements of the Cochrane systematic review. According to whether the heterogeneity of the study was significant or not, a random effect model or a fixed effect model were used to conduct the analysis on the impact of different types of SGLT2i on 24-hour ambulatory blood pressure and day and night blood pressure in patients with type 2 diabetes and hypertension. Further subgroup analysis was performed to define potential factors, which might lead to clinical heterogeneity. Results: Seven clinical trials were finally included. The result of the meta-analysis showed that compared with placebo group, SGLT2i could reduce the 24-hour dynamic systolic blood pressure of patients with type 2 diabetes and hypertension by 4.36 mmHg (1 mmHg=0.133 kPa). Reduction was 4.59, 3.74, 5.06, and 3.64 mmHg by canagliflozin, dapagliflozin, empagliflozin, and ertugliflozin respectively; SGLT2i could reduce the 24-hour dynamic diastolic blood pressure of patients with type 2 diabetes and hypertension by 2.20 mmHg, and the reduction was 2.30, 1.22, 2.00, and 2.69 mmHg by canagliflozin, dapagliflozin, empagliflozin and ertugliflozin respectively. SGLT2i could reduce the daytime systolic blood pressure of patients with type 2 diabetes and hypertension by 5.25 mmHg, and reduction was 5.38, 4.87, 6.00, and 4.37 mmHg by canagliflozin, dapagliflozin, empagliflozin and ertugliflozin, respectively. Simultaneously, SGLT2i could reduce the diastolic blood pressure of patients with type 2 diabetes and hypertension by 2.62 mmHg, and the reduction was 2.56, 2.47, and 2.80 mmHg by canagliflozin, empagliflozin and ertugliflozin, respectively. SGLT2i could reduce the nighttime systolic blood pressure of patients with type 2 diabetes and hypertension by 3.62 mmHg, and the reduction was 2.09, 2.06, 3.92, and 2.45 mmHg by canagliflozin, dapagliflozin, empagliflozin and ertugliflozin, respectively. At the same time, SGLT2i could reduce the nighttime diastolic blood pressure of patients with type 2 diabetes and hypertension by 1.60 and 1.51 mmHg, the reduction was 1.53 and 2.58 mmHg by canagliflozin, empagliflozin and ertugliflozin, respectively. Conclusion: SGLT2i can reduce 24-hour ambulatory blood pressure in patients with type 2 diabetes and hypertension.

[Comparison of preoperative chemotherapy with concurrent chemoradiotherapy combined with TME for 305 patients with locally advanced rectal cancer]

Objective: To retrospectively analyze the long-term efficacy and prognostic factors of preoperative chemotherapy (PCT) or chemoradiotherapy (PCRT) combined with total mesorectal excision in locally advanced rectal cancer. Methods: Clinical pathology data of 305 patients with localized advanced rectal cancer admitted to the Cancer Hospital, Chinese Academy of Medical Sciences from 2006 to 2018 were collected, of whom 246 patients received PCRT (PCRT group), 59 patients received PCT (PCT group). Kaplan-Meier and Log rank test were used for the survival analysis, Cox regression model was used for multivariate analysis, and the prognosis of two groups of patients were compared by the propensity score matching (PSM). Results: In the whole group of 305 patients, 20 cases of tumors located in the upper part of the rectum and at the junction of rectum and colon, 96 cases in the middle of the rectum and 189 cases in the lower part of the rectum. PCRT group included 38 cases of cT2-3 phase, 11 cases of cT4a stage, 10 cases of cT4b stage, while the cases in PCT group were 184, 0 and 62 cases, respectively, the difference is statistically significant (P<0.05). The R0 excision rates of PCRT group and PCT group were 100% (246/246) and 96.6% (57/59), respectively, and the total pathological remission rates were 13.4% and 3.3%, respectively (P<0.05). After PSM, the 3-year survival rates of PCRT group and the PCT group were 86.6% and 89.9% (P>0.05), respectively, and the progression-free survival rates were 74.6% and 77.2% (P>0.05), local recurring free survival rates were 100% and 92.3% (P>0.05), distant metastasis free survival rate were 75.6% and 77.3% (P>0.05). Pre-treatment N-positive, N-degeneration and MRF-positive were all associated with total survival (P<0.05). Conclusion: In the PCRT group, with a higher proportion of patients with stage T4b and lower rectal cancer, the long-term efficacy of PCRT was similar to that of PCT, and higher R0 excision rate and pathological complete response rate could be obtained.

[Outcome of radiotherapy for low-risk early-stage patients with extranodal NK/T-cell lymphoma, nasal-type]

Objective: To evaluate the prognosis and determine the failure patterns after radiotherapy for low-risk early-stage patients with extranodal NK/T-cell lymphoma, nasal-type (ENKTCL). Methods: A total of 557 patients from 2000-2015 with low-risk early-stage ENKTCL who received radiotherapy (RT) with or without chemotherapy (CT) from China Lymphoma Collaborative Group were retrospectively reviewed. Among them, 427 patients received combined modality therapy, whereas 130 patients received RT alone. Survivals were calculated by Kaplan-Meier method and compared with Log-rank test. Overall survival (OS) was compared with age and sex-matched general Chinese population using expected survival and standardized mortality ratio (SMR). Cox stepwise regression model was used for multivariate analysis. Results: The 5-year OS and progression-free survival (PFS) were 87.2% and 77.2%. The SMR was 3.59 (P<0.001) at 1 year after treatment, whereas it was 1.50 at 4 years after treatment, without significant difference between ENKTCL group and country-matched general population (P=0.146). Compared with RT alone, CMT did not result in significantly superior 5-year OS (87.0% vs 87.4%, P=0.961) or PFS (76.1% vs 80.7%, P=0.129). Local failure (11.5%, 64/557) and distant failure (10.8%, 60/557) were the main failure modes, while regional failure was rare (2.9%, 16/557). The 5-year locoregional control rate (LRC) was 87.2% for the whole group, with 89.5% for ≥50 Gy versus 73.7% for <50 Gy (P<0.001). Radiotherapy dose was an independent factor affecting LRC(P<0.05). Conclusions: Radiotherapy achieves a favorable prognosis in patients with low-risk early-stage ENKTCL. The incidence of either locoregional or distant failure is low. Radiation dose still is an important prognostic factor for LRC.

Efficacy and toxicity of capecitabine combined with intensity-modulated radiotherapy after D1/D2 lymph node dissection in patients with gastric cancer

BACKGROUND

Adjuvant chemoradiotherapy (ACRT) with oral capecitabine and intensity-modulated radiotherapy (IMRT) were well tolerated in a phase I study in patients who had undergone partial or total gastrectomy for locally advanced gastric cancer (GC). This phase II study aimed to further determine the efficacy and toxicity of this combination after radical resection and D1/D2 lymph node dissection (LND) for patients with locally advanced GC.

AIM

To further determine the efficacy and toxicity of this combination after radical resection and D1/D2 LND for patients with locally advanced GC.

METHODS

Forty patients (median age, 53 years; range, 24-71 years) with pathologically confirmed adenocarcinoma who underwent D1/D2 LND were included in this study. The patients received ACRT comprising IMRT (total irradiation dose: 45 Gy delivered in daily 1.8-Gy fractions on 5 d a week over 5 wk) and capecitabine chemotherapy (dose: 800 mg/m² twice daily throughout the duration of radiotherapy). The primary study endpoint was disease-free survival (DFS), and the secondary endpoints were overall survival (OS), toxic effects, and treatment compliance.

RESULTS

The 3-year DFS and OS were 66.2% and 75%, respectively. The median time to recurrence was 19.5 mo (range, 6.1-68 mo). Peritoneal implantation (n = 10) was the most common recurrence pattern, and the lung was the most common site of extra-abdominal metastases (n = 5). Nine patients developed grade 3 or 4 toxicities during ACRT. Two patients discontinued ACRT, while eleven underwent ACRT without receiving the entire course of capecitabine. There were no treatment-related deaths.

CONCLUSION

The ACRT protocol described herein showed acceptable safety and efficacy for patients with locally advanced GC who received radical gastrectomy and D1/2 LND.

Quality of Life After Partial or Whole-Breast Irradiation in Breast-Conserving Therapy for Low-Risk Breast Cancer: 1-Year Results of a Phase 2 Randomized Controlled Trial

Purpose

To report patients’ quality of life (QoL) at 1 year in a phase 2 randomized trial comparing partial breast irradiation (PBI) with whole-breast irradiation (WBI) after breast-conserving surgery (BCS) for breast cancer.

Methods

Women aged ≥ 45 years with low-risk breast cancer after BCS were randomly assigned (1:1) to receive PBI (40 Gy in 10 fractions over 2 weeks) or WBI (43.5 Gy in 15 fractions over 3 weeks). The primary endpoint—the incidence of toxicities of grade 2 or higher—will be reported when participants complete 5 years of follow-up. QoL was assessed at baseline (T0), at the end of radiotherapy (RT) (T1), 6 months (T2) and 1 year (T3) after RT by using the EORTC QLQ-C30 and QLQ-BR23 questionnaires. We calculated the scores for all QOL subscales and differences in mean scores were compared. This study was registered at ClinicalTrials.gov (NCT03583619).

Results

Between June 2017 and January 2019, 140 women were randomly assigned to receive PBI or WBI (n = 70 per group). Fifty-nine and 56 patients treated with PBI and WBI, respectively, were eligible for the QoL analysis. There were no significant differences in any subscale scores at T0, T1, T2, or T3 between the PBI and WBI arms. The scores for most QoL subscales that were influenced by RT recovered to a similar or better level relative to T0 scores within 1 year after RT, except for the scores of the dyspnea subscale. Longitudinal analysis showed that time since RT had a significant impact on physical functioning, role functioning, social functioning, fatigue, pain, dyspnea, financial difficulties, body image, and breast and arm symptoms.

Conclusion

PBI using the intensity-modulated RT affords QoL comparable to that provided by WBI. Most QoL subscale scores that were influenced by RT recovered to a similar or better level relative to baseline scores within 1 year after RT.

Radiomics Analysis of Fat-Saturated T2-Weighted MRI Sequences for the Prediction of Prognosis in Soft Tissue Sarcoma of the Extremities and Trunk Treated With Neoadjuvant Radiotherapy

Purpose

To create a prognostic prediction radiomics model for soft tissue sarcoma (STS) of the extremities and trunk treated with neoadjuvant radiotherapy.

Methods

This study included 62 patients with STS of the extremities and trunk who underwent magnetic resonance imaging (MRI) before neoadjuvant radiotherapy. After tumour segmentation and preprocessing, 851 radiomics features were extracted. The radiomics score was constructed according to the least absolute shrinkage and selection operator (LASSO) method. Survival analysis (disease-free survival; DFS) was performed using the log-rank test and Cox’s proportional hazards regression model. The nomogram model was established based on the log-rank test and Cox regression model. Harrell’s concordance index (C-index), calibration curve and receiver operating characteristic (ROC) curve analysis were used to evaluate the prognostic factors. The clinical utility of the model was assessed by decision curve analysis (DCA).

Results

The univariate survival analysis showed that tumour location (p = 0.032), clinical stage (p = 0.022), tumour size (p = 0.005) and the radiomics score were correlated with DFS (p < 0.05). The multivariate analysis showed that tumour location, tumour size, and the radiomics score were independent prognostic factors for DFS (p < 0.05). The combined clinical-radiomics model based on the multivariate analysis showed the best predictive ability for DFS (C-index: 0.781; Area Under Curve: 0.791). DCA revealed that the use of the radiomics score-based nomogram was associated with better benefit gains relative to the prediction of 2-year DFS events than other models in the threshold probability range between 0.12 and 0.38.

Conclusion

The radiomics score from pretreatment MRI is an independent prognostic factor for DFS in patients with STS of the extremities and trunk. The radiomics score-based nomogram could improve prognostic stratification ability and thus contribute to individualized therapy for STS patients.

[Correlation between aspiration and long-term survival of inpatients with chronic obstructive pulmonary disease]

Objective: To retrospectively analyze the high risk factors of death in patients with chronic obstructive pulmonary disease (COPD) and to explore the influence of aspiration on the long-term survival rate of COPD patients. Methods: A retrospective analysis of clinical data of inpatients, who were admitted to the First Affiliated Hospital of Guangzhou Medical University from April 2012 to December 2013 due to COPD exacerbations and had radionuclide aspiration test, was conducted. Meanwhile, we phoned the patients' family members, whose phone numbers were recorded in the electronic patient record system, to follow up the patients' survival status, and learn the causes of death from their death records if patients died during follow-up period. Inquired the resident administration patients belonging to according to their original address to get patient's current contact information if changed. Besides, if family members of patients failed to provide death record, we should look up information concerned from the medical records room of the hospital where they died. Results: The follow-up for the last patient was performed on February 20, 2017.The time span of this study is 58 months, starting from the radionuclide aspiration test for the first patient and ending with the follow-up for the last patient. 16 of the 53 patients(16/53, 30.2%)were tested positive whose average age was slightly higher than patients without aspiration (76.0±6.8 vs 70.9±9.9), but there was no significant difference between them(P=0.064). The aspiration rates among patients over and under the age of seventy were 14/35 and 2/18 respectively, and there was a significant difference between them(P = 0.03). Compared to the aspiration-negative patients, the aspiration-positive patients had higher incidence rate of pneumonia in COPD exacerbations (11/16 vs 9/37, χ²= 9.383, P = 0.002).The major cause of death in the patients with and without aspiration were respectively severe pneumonia and pulmonary encephalopathy(P<0.05 in both cases).Among COPD patients who took radionuclide aspiration test, the median survival time of the patients with and without aspiration were about 3 and 5 years respectively. The high-risk factors influencing long-term survival of the COPD patients with aspiration included ICU-involved medical history and accompanying pneumonia. Conclusions: The incidence rate of aspiration is relatively high in COPD patients over 70 years old. Compared to COPD patients without aspiration, COPD patients with aspiration have higher incidence rate of pneumonia and shorter median survival time. ICU-involved medical history and severe pneumonia are the two high-risk factors influencing long-term survival of COPD patients with aspiration.To improve the survival time of COPD patients with aspiration, we need to attach importance to the prevention and treatment of aspiration.

[Screening and analysis of Treponema pallidum specific antibody among childbearing age people in rural areas of Yunnan province, 2013-2017]

Objective: To determine the prevalence, epidemiological characteristics, and related factors of syphilis infection among rural childbearing age people to promote medical interventions on pre-pregnancy aristogenesis and syphilis infection in Yunnan province. Methods: The subjects in this study were 18-49-year-old rural couples of childbearing age from the National Free Preconception Health Examination Project in Yunnan province during 2013-2017. The descriptive study was carried out to determine the positive rate of Treponema pallidum specific antibody (TPsAb) and related sociodemographic characteristics. Results: The overall positive rate of TPsAb was 0.38% (8 204/2 160 455) in 2 160 455 rural childbearing age people in Yunnan. The positive rate of TPsAb was 0.39% (4 019/1 040 981) in men,higher than that in women (0.37%,4 185/1 119 474). The positive rate of TPsAb was highest in the age group 45-49 years (0.70%,158/22 511). The positive rate of TP antibody in the minority ethnic groups and Han ethnic groups appeared the same (0.38%). However,the highest positive rate of TPsAb was 0.77% (461/60 153) in Hani ethnic group among all the 17 minority ethnic groups. People with education level of primary education had the highest anti-TP positive rate (0.54%,2 327/431 275). The positive rate of TPsAb appeared the highest in Zhaotong (0.73%, 2 049/281 614) area among all the 16 prefectures of the province. The positive rate of TPsAb in the population from the impoverished regions (0.50%,2 963/590 039) was higher than in other disadvantaged areas (0.34%, 3 115/929 368) or areas with average income (0.33%,2 126/641 048). Significant differences appeared in the positive rate of TPsAb among populations of different ages, ethnic, education level, and economic level groups (trend χ² test, P<0.001). Conclusions: The positive rate of TP antibody in rural childbearing age people in Yunnan was related to multi factors,including sex,age,ethnic group,education level,area, residence, and local economic situation. The positive rate of TPsAb was higher in men than in women. And people with elder age, lower education level, being Hani or Lahu ethnic group, and Zhaotong areas had higher TPsAb positive rates and higher syphilis infection risk.

Ultrafast X-Ray Diffraction Visualization of B1-B2 Phase Transition in KCl under Shock Compression

The classical B1(NaCl)↔B2(CsCl) transitions have been considered as a model for general structural phase transformations, and resolving corresponding phase transition mechanisms under high strain rate shock compression is critical to a fundamental understanding of phase transition dynamics. Here, we use subnanosecond synchrotron x-ray diffraction to visualize the lattice response of single-crystal KCl to planar shock compression. Complete B1-B2 orientation relations are revealed for KCl under shock compression along ⟨100⟩_{B1} and ⟨110⟩_{B1}; the orientation relations and transition mechanisms are anisotropic and can be described with the standard and modified Watanabe-Tokonami-Morimoto model, respectively, both involving interlayer sliding and intralayer ion rearrangement. The current study also establishes a paradigm for investigating solid-solid phase transitions under dynamic extremes with ultrafast synchrotron x-ray diffraction.

[Formation of study population for causal inference]

Epidemiological analysis describes and compares the characteristics of a certain number of people to make causal inferences. The formation of the study population is always the first step. In this paper, we first define the concepts of cross-sections at both individual level and population level and introduce the three assumptions needed in the measurements in observational studies, i. e. the true values of the attributes are stable with time, the attribute variables are independent and the individuals are independent during the measuring process. We also determine that the causal inference research should be unified based on the time of the occurrence or beginning of a postulated cause, or exposure, should be in. Then, based on the dual roles of the population cross-section with causal thinking, we propose that research designs can be classified into two types with different characteristics: history reconstruction research and future exploration research. Finally, we briefly analyze the research design framework and the relationship between estimated effects and different designs. The discussion of the formation of a study population from the perspective of causal thinking can make a foundation for the classification of causal inference research design with appropriate effect parameters, which needs to be further studied.