Objective Evaluate the accuracy o f co-registration of PET and C T (PET-CT) images on line with phantom, and utilize it on patients to provide c l inical evidence for target delineation in radiotherapy. Methods A phantom with m arkers and different volume cylinders was infused with various concentrations of 18FDG, and scanned at 4?mm by PET and CT respectively. Aft er having been transmi tted into GE eNTEGRA and treatment planning system (TPS) workstations, the image s were fused and reconstructed. The distance between the markers and the errors were monitored in PET and CT images respectively. The volume of cylinder in PET and CT images were measured and compared by certain pixel value proportion deduc tion method. The same procedure was performed on the pulmonary tumor image in te n patients. Results eNTEGRA and TPS workstations had a good length linearity, b ut the fusion error of the latter was markedly greater than the former. Tumors i n different volume filled by varying concentrations of 18FDG required different pixel deduction proportion. The cylinder volume of PET and CT images were almost the same, so were the images of pulmonary tumor of ten patients. Conclusions T he accuracy of image co-registration of PET-CT on line may fulfill the clinica l demand. Pixel value proportion deduction method can be used for target delineati on on PET image.

Objective To investigate the value of 18 F-fluorodeoxyglucose FDG) positron emission tomography (PET)-computed tomography (CT) in predicting the progression-free survival (PFS)and overall survival (OS) of patients with esophageal squamous cell carcinoma (ESCC) after threedimensional (3D) radiotherapy.Methods A retrospective analysis was performed on 98 ESCC patients,who underwent FDG PET-CT before 3D radiotherapy from 2004 to 2010,to investigate their 1-,3-,and 5-year PFS and OS rates.The relationship of maximum standard uptake value (SUVmax),mean SUV (SUVmean),metabolic target volume (MTV),length of primary tumor on PET-CT before radiotherapy,and number of tumors on PET with PFS and OS were analyzed.The SUVs and clinical data were analysed by independent samples t-test or Hotelling T2 test; the Kaplan-Meier method was used for calculating PFS and OS rates,and the Logrank test was used for survival difference analysis;the prognostic factors were analysed using the Cox proportional hazard model.Results The follow-up rate was 100％ ;56 patients were followed up for at least 3 years,and 27 for at 5 years.The SUVmax SUVmean and MTV of primary tumor,length of primary tumor on PET-CT before radiotherapy,and number of tumors on PET were correlated with PFS and OS (x2 =8.99-41.82,all P ＜ 0.01).The Cox regression analysis showed that PFS could be well predicted based on SUVmean (x2 =4.41,P =0.036,RR =1.398) and number of tumors on PET (x2 =6.79,P =0.009,RR =3.650) and that OS could be well predicted based on number of tumors on PET (x2 =5.03,P =0.025,RR =3.740).Conclusions When estimating the long-term response to precise radiotherapy in patients with ESCC,SUV mean and number of tumors on PET may be used to predict PFS,and number of tumors on PET may be used to predict OS.

Objective To compare the difference of decreasing radiation-induce lung injure among CT scans including active breathing control (ABC), slow CT scan and general axial CT scan under free breathing (FB) in precise radiotherapy of peripheral non-small cell lung cancer (NSCLC). Methods Ten patients of peripheral NSCLC were included. For each patient, three CT scans were obtained: (1) the general axial CT scans under FB;(2) the fast spiral CT scans under ABC;(3) the slow CT scans under FB. Three treatment plans based on three CT scans were optimized. Gross tumor volume (GTV), clinical target volume (CTV) and planning target volume (PTV) along with V20 (lung volume accepted > 20 Gy/all lung volume ×100%) and Dmean (average dosage accepted irradiation of all lung)of three treatment plans were calculated and compared. Results The GTV and CTV of the slow CT plan seem in largest, and those of ABC plan in smallest, but no statistics signification among the three plans (F = 1.513, P = 0.238;F = 1.376, P = 0.270). However, The PIV of the FB plan was largest, and the difference of PTV between plans of ABC and FB, plans of slow CT scans and FB were statistics significant (F = 26. 148, P = 0.000). The differences of V20 and Dmean between plans of FBand ABC, plans of FB and slow CT scans were statistics significant yet (F = 7.623, P = 0.002;F = 18.217, P = 0.000). Conclusion Compared with FB conditions, ABC or the slow CT scan method in precise radiotherapy of peripheral NSCLC can decrease radiation volume and dose to normal tissues as well as the probability of decreasing radiation-induce lung injure.

Objective To evaluate therapeutic effects and complications of concurrent three-dimensional conformal radiotherapy (3DCRT) and chemotherapy in patients with limited-stage small cell lung cancer (LSCLC).Methods From June 2000 to August 2005, 93 histologically proved LSCLC patients were randomized into two groups:3DCRT group (n =46) and conventional group (n =47).In both groups, patients received one cycle chemotherapy, followed by concurrent chemoradiotherapy and then received consolidate chemotherapy.Chemotherapy was four to six cycles of PE regimen.Conventional irradiation field was setup in conventional group, while in 3 DCRT group clinical target volume (CTV) only involved visible tumor and adjacent lymphatic region.Radiotherapy was delivered at 2 Gy per fraction, 5 fractions per week to a median total dose of 60 -64 Gy.Those who achieved a complete response were treated with prophylactic cranial irradiation (PCI) with 30 Gy in 10 fractions.Results The follow-up rate was 100% in both groups.The number of patients completed 1-, 2-and 3-year follow-up were 36, 34 and 16 in 3DCRT group, 14, 7 and 8 in conventional group, respectively.The complete and overall response rate were 52% and 89% in 3DCRT group, while 47% and 85% in conventional group, respectively.The 1-, 2-and 3-year survival rates were 78%, 35% and 15% in 3DCRT group, 72%, 30% and 17% in conventional group, respectively.The median survival time was 23.2 and 22.8 months, respectively.There was no statistical difference in short-term (Χ~2 = 0.34 ,P = O.759) and long-term outcomes (Χ~2 = 0.18 ,P = 0.92).In 3DCRT group, the incidence of grade 1 +2 acute radiation pneumonitis and esophagitis, grade 1 +2 and grade 3 chronic radiation pneumonitis were lower than those in conventional group.There was no grade 3 or 4 acute radiation pneumonitis or esophagitis, or grade 4 chronic radiation pneumonitis in both groups.There was no difference in grade 1 + 2, grade 3 or grade 4 acute myelo-suppression between the two groups.Conclusions In the treatment of LSCLC, concurrent 3DCRT and chemotherapy can achieve satisfactory short-term and long-term outcomes with acceptable complications.

Objective To discuss the value of dual-time-point 18FDG PET-CT imaging on involved field radiotherapy for hilar and mediastinal metastatic lymph nodes in patients with non-small cell lung cancer (NSCLC).Methods Fifty-four patients with NSCLC were included in this analysis,including 34 men and 20 women with mean age of 59(34-76)years.Two sequential PET-CT scans given 3-5 days before surgery were standard single-time-point imaging for the whole body and delayed imaging for the thorax.The pathologic data were used as golden standard to determine the difference between the standard single-time-point and dual-time-point FET-CT imaging in the definition of gross target volume(GTV)of involved-field radiotherapy for metastatic lymph nodes. Results For hilar metastatic lymph nodes,the GTV defined by single-time-point imaging was consistent with pathologic GTV in 21 patients(39%),comparing with 31 patients(57%) by dual-time-point imaging.Using pathologic data as golden standard,GTV alteration defined by single-time-point imaging had statisticaly significant difference comparing with that defined by dual-time-point imaging(u=519.00,P=0.023).For mediastinal metastatic lymph nodes,the GTV defined by single-time-point imaging was consistent with pathologic GTV in 30 patients(56%),comparing with 36 patients(67%)by dual-time-point imaging.Using pathologic data as golden standard.GTV alteration defined by single-time-point imaging had no statisticaly significant difference comparing with that defined by dual-time-point imaging(u=397.50,P=0.616).Conclusions For patients with NSCLC receiving involved-field radiotherapy,GTV definition for hilar and mediastinal metastatic lymph nodes by dual-time-point imaging is more consistent with that by pathologic data.Dual-time-point imaging has a larger value in terms of target delineation for hilar and mediastinal metastatic lymph nodes.

The standard treatment mode for locally advanced operable esophageal carcinoma is neoadjuvant chemoradiotherapy combined with radical esophagectomy. However, considering the clinical need for organ retention, the treatment strategies for those achieving complete clinical response after neoadjuvant chemoradiotherapy include watchful waiting (omitting surgery), delayed or salvage surgery, and strengthened systemic treatment. These treatment strategies can significantly improve the quality of patients' life while ensuring local control and long-term survival. The feasibility and clinical value of these treatment strategies are deeply explored, hoping to provide new treatment ideas for this group of patients.

Objective:To investigate distribution characteristics of Treponema pallidum (Tp) in secondary syphilis lesions, and to analyze its correlation with histopathological findings. Methods:Totally, 41 patients were collected from Department of Dermatology and Venereology, Peking Union Medical College Hospital from January 2008 to December 2018, who were confirmedly diagnosed with secondary syphilis according to clinical manifestations and serological examinations, and had undergone histopathological examinations. Immunohistochemical results of skin tissue sections were analyzed, and differences in clinical and histopathological characteristics were analyzed between immunohistochemically Tp-positive and Tp-negative sections. Continuous data were compared by using t test or Kruskal-Wallis test, and categorical data were compared by using Chi-square test or Fisher′s exact test. Results:Immunohistochemical examination showed that Tp was detected in 68.3% of the 42 secondary syphilis tissue sections, and Tp was mainly distributed in the lower epidermis and superficial and middle dermis. The positive rate of Tp was significantly higher in secondary syphilis lesions mainly manifesting as maculae (80% [16/20]) than in those mainly manifesting as papules (50% [11/22], P < 0.05) . Among 10 pathological characteristics, extended rete ridges, basal cell liquefaction degeneration, neutrophil infiltration in the stratum corneum, lichenoid pattern of infiltration and punctate keratinocyte necrosis were observed more frequently in immunohistochemically Tp-positive sections than in Tp-negative sections (all P < 0.05) . Immunohistochemical study revealed that tissue sections with a larger number of Tp showed more pathological features ( H = 17.914, P < 0.001) . Immunohistochemical staining showed that there were 8, 7 and 6 syphilis-specific histopathological characteristics on average in 8 tissue sections with a larger number of Tp, 14 with a medium number of Tp and 5 with a small number of Tp, respectively; while only 4 syphilis-specific histopathological characteristics were observed on average in 15 immunohistochemically Tp-negative tissue sections. Conclusion:Immunohistochemical staining could show the distribution of Tp in secondary syphilis lesions, and it seems that tissue sections with a larger number of Tp present with more syphilis-specific histopathological characteristics.

Neoadjuvant chemoradiotherapy is the preferred treatment mode for the diagnosis and treatment of locally advanced operable esophageal carcinoma recommended by many guidelines. However, some problems remain to be further explored. In this article, current problems perplexing clinical practice were sorted out, aiming to provide constructive suggestions for the smooth development of neoadjuvant chemoradiotherapy for esophageal carcinoma in the future.

Objective:To explore the clinical efficacy and safety of the camrelizumab combined with apatinib and chemotherapy as second-line or later therapy in human epidermal growth factor receptor-2 (HER-2) negative advanced gastric cancer.Methods:A total of 66 patients with HER-2 negative advanced gastric cancer and first-line treatment failure in Shandong Cancer Hospital Affiliated to Shandong First Medical University from March 2018 to September 2021 were selected. They were divided into study group ( n=22) and control group ( n=44) according to the different treatment regimens. The patients in the study group were treated with camrelizumab combined with apatinib and chemotherapy, and the patients in the control group were treated with chemotherapy alone. The short-term efficacy, progression-free survival (PFS) , overall survival (OS) and the occurrence of adverse reactions were compared, and Cox regression analysis was used to analyze the influencing factors of prognosis. Results:After at least 2-4 cycles of treatment, the ORR in the study group and the control group were 9.1% (2/22) and 0 (0/44) respectively, with no statistically significant difference ( P=0.108) . DCR in the two groups were 77.3% (17/22) and 45.5% (20/44) respectively, with a statistically significant difference ( χ2=6.03, P=0.014) . The study group didn’t reach median OS and the median OS in the control group was 11.7 months, with no statistically significant difference ( χ2=1.59, P=0.207) . The study group didn’t reach median PFS and the median PFS in the control group was 3.2 months, with a statistically significant difference ( χ2=10.13, P=0.001) . Multivariate Cox regression analysis showed that treatment method was an independent influencing factor for PFS in patients with HER-2 negative advanced gastric cancer ( HR=0.33, 95% CI: 0.15-0.75, P=0.008) . In terms of adverse reactions, there was a statistically significant difference in the incidence of elevated alanine aminotransferase between the study group and the control group [31.8% (7/22) vs. 6.8% (3/44) , χ2=5.32, P=0.021]. There were no adverse-related deaths in both groups. Conclusion:Compared with chemotherapy alone, camrelizumab combined with apatinib and chemotherapy as a second-line or later therapy in HER-2 negative advanced gastric cancer can prolong PFS and improve DCR, but the incidence of elevated alanine aminotransferase increases significantly.