Colorectal cancer (CRC) ranks among the most prevalent malignancies globally, posing a substantial threat to public health. At initial diagnosis, 20%-25% of patients present with metastatic disease, while 50% of localized cases eventually progress to metastatic colorectal cancer (mCRC). The prognosis for mCRC remains poor, with a 5-year survival rate below 20%. Precision medicine, an individualized and deeply stratified approach to disease prevention and management, demonstrates exceptional potential in treatment of CRC.The pathogenesis and progression of CRC are closely linked to diverse genetic abnormalities. Through genomic profiling to define clinically actionable subgroups, the efficacy of targeted therapies and immunotherapies can be significantly enhanced. The mutational status of RAS and BRAF genes holds critical importance in guiding therapeutic selection for targeted agents. Patients with DNA mismatch repair deficiency/microsatellite instability-high status exhibit notable responses to immunotherapies. Emerging modalities such as chimeric antigen receptor-T-cell immunotherapy and fecal microbiota transplantation show therapeutic promise in mCRC. Additionally, circulating tumor DNA, multi-omics technologies, and artificial intelligence are increasingly utilized in early screening, diagnostic refinement, treatment response monitoring, and prognostic prediction. The authors comprehensively discuss the current status and advances in precision diagnosis and treatment of metastatic colorectal cancer from perspectives including genomic abnormalities, targeted therapy, immunotherapy, and future directions.

Colorectal cancer (CRC) ranks among the most prevalent malignancies globally, posing a substantial threat to public health. At initial diagnosis, 20%-25% of patients present with metastatic disease, while 50% of localized cases eventually progress to metastatic colorectal cancer (mCRC). The prognosis for mCRC remains poor, with a 5-year survival rate below 20%. Precision medicine, an individualized and deeply stratified approach to disease prevention and management, demonstrates exceptional potential in treatment of CRC.The pathogenesis and progression of CRC are closely linked to diverse genetic abnormalities. Through genomic profiling to define clinically actionable subgroups, the efficacy of targeted therapies and immunotherapies can be significantly enhanced. The mutational status of RAS and BRAF genes holds critical importance in guiding therapeutic selection for targeted agents. Patients with DNA mismatch repair deficiency/microsatellite instability-high status exhibit notable responses to immunotherapies. Emerging modalities such as chimeric antigen receptor-T-cell immunotherapy and fecal microbiota transplantation show therapeutic promise in mCRC. Additionally, circulating tumor DNA, multi-omics technologies, and artificial intelligence are increasingly utilized in early screening, diagnostic refinement, treatment response monitoring, and prognostic prediction. The authors comprehensively discuss the current status and advances in precision diagnosis and treatment of metastatic colorectal cancer from perspectives including genomic abnormalities, targeted therapy, immunotherapy, and future directions.

Objective:To compare four postmastectomy radiotherapy plans with different arc angles for left-sided breast cancer prepared using deep inspiration breath hold (DIBH) technique, in order to explore the feasibility of selecting optimal arc angles based on the parameters of patients′ anatomical structures.Methods:A total of 51 patients who underwent postmastectomy radiotherapy for left-sided breast cancer using DIBH at the Second Affiliated Hospital of Guangxi Medical University and the First Affiliated Hospital of Guangzhou Medical University were selected. Among these, 40 patients selected using simple random sampling were treated with four radiotherapy plans with different arc angles, labeled as SV120, SV100, SV80, and SV60, while the remaining 11 patients were treated with only the SV60 plans. The dose parameters of the target volumes (TVs) and organs at risk (the heart, lungs, and contralateral breast), as well as the beam-on times of individual arcs, in these plans were compared. The parameters of the anatomical structures (i.e., the heart, lung, and breast) of the 51 patients, including PHeart, PLungl, and PBreast, were extracted. Taking these parameters as independent variables and the quality of the SV60 plans as the dependent variable, fitting was conducted using P(SV60)—a multivariate logistic regression model—based on a training set (45 patients) and a testing set (six patients). The classification threshold of the plans was set at 0.5. Results:As the arc angle increased, the plans exhibited improved modulation capabilities for TVs and the left lung. However, the V5 of the right lung and the average beam-on time of a single arc also increased. The SV120 plans demonstrated significantly better V107% of planning target volume (PTV; 6.84%), homogeneity index (HI; 0.13), conformity index (CI; 0.81), and mean dose to the left lung (1 330.97 cGy) compared to the other three types of plans, with statistically significant differences ( W = 0-99, P < 0.001). The SV60 plans displayed lower mean doses to the contralateral breast (198.97 cGy) and the heart (440.35 cGy) and lower V5 of the right lung (0.27%) than the other three types of plans, with significant differences in V5 of the right lung and the mean dose to the contralateral breast ( W = 0-157, P < 0.001). In contrast, no significant difference was observed in these parameters (except for V5 of the right lung) among the other three types of plans. The four types of plans exhibited average beam-on times of individual arcs of 22.0, 19.1, 16.1, and 14.4 s, respectively, with statistically significant differences ( χ2= 93.0, P < 0.001). A multivariate logistic regression model revealed that PLungl, PHeart, and PBreast were negatively correlated with the quality of the SV60 plans ( t = -64.84, -28.20, -24.45, P<0.001). This model yielded an accuracy of 93.33% and a precision of 92.86% in the training set, while its accuracy and precision reached 100% in the testing set. Conclusions:For patients treated with postmastectomy radiotherapy for left-sided breast cancer using DIBH, it is feasible to select appropriate arc angles based on patients’ anatomical structures.

Objective:To compare four postmastectomy radiotherapy plans with different arc angles for left-sided breast cancer prepared using deep inspiration breath hold (DIBH) technique, in order to explore the feasibility of selecting optimal arc angles based on the parameters of patients′ anatomical structures.Methods:A total of 51 patients who underwent postmastectomy radiotherapy for left-sided breast cancer using DIBH at the Second Affiliated Hospital of Guangxi Medical University and the First Affiliated Hospital of Guangzhou Medical University were selected. Among these, 40 patients selected using simple random sampling were treated with four radiotherapy plans with different arc angles, labeled as SV120, SV100, SV80, and SV60, while the remaining 11 patients were treated with only the SV60 plans. The dose parameters of the target volumes (TVs) and organs at risk (the heart, lungs, and contralateral breast), as well as the beam-on times of individual arcs, in these plans were compared. The parameters of the anatomical structures (i.e., the heart, lung, and breast) of the 51 patients, including PHeart, PLungl, and PBreast, were extracted. Taking these parameters as independent variables and the quality of the SV60 plans as the dependent variable, fitting was conducted using P(SV60)—a multivariate logistic regression model—based on a training set (45 patients) and a testing set (six patients). The classification threshold of the plans was set at 0.5. Results:As the arc angle increased, the plans exhibited improved modulation capabilities for TVs and the left lung. However, the V5 of the right lung and the average beam-on time of a single arc also increased. The SV120 plans demonstrated significantly better V107% of planning target volume (PTV; 6.84%), homogeneity index (HI; 0.13), conformity index (CI; 0.81), and mean dose to the left lung (1 330.97 cGy) compared to the other three types of plans, with statistically significant differences ( W = 0-99, P < 0.001). The SV60 plans displayed lower mean doses to the contralateral breast (198.97 cGy) and the heart (440.35 cGy) and lower V5 of the right lung (0.27%) than the other three types of plans, with significant differences in V5 of the right lung and the mean dose to the contralateral breast ( W = 0-157, P < 0.001). In contrast, no significant difference was observed in these parameters (except for V5 of the right lung) among the other three types of plans. The four types of plans exhibited average beam-on times of individual arcs of 22.0, 19.1, 16.1, and 14.4 s, respectively, with statistically significant differences ( χ2= 93.0, P < 0.001). A multivariate logistic regression model revealed that PLungl, PHeart, and PBreast were negatively correlated with the quality of the SV60 plans ( t = -64.84, -28.20, -24.45, P<0.001). This model yielded an accuracy of 93.33% and a precision of 92.86% in the training set, while its accuracy and precision reached 100% in the testing set. Conclusions:For patients treated with postmastectomy radiotherapy for left-sided breast cancer using DIBH, it is feasible to select appropriate arc angles based on patients’ anatomical structures.

Objective:To explore the relationship between Epstein-Barr virus (EBV) infection, hepatitis B virus (HBV) reactivation and clinical features and prognosis in HBV-infected non-Hodgkin lymphoma (NHL) patients and influencing factors of HBV reactivation.Methods:A retrospective cohort study was conducted. A total of 80 NHL patients with hepatitis B surface antigen (HBsAg) positive (which was defined as HBV positive) who were admitted to the Second People's Hospital of Lianyungang and Jiangsu Province Hospital from December 2012 to October 2022 were selected. All patients were divided into EBV-positive group and EBV-negative group according to EBV DNA results, and further grouped into the HBV reactivation group and the non-reactivation group according to whether HBV were reactivated after chemotherapy. The clinical characteristics of patients among groups were compared. Multivariate logistic regression model was used to analyze the factors influencing HBV reactivation. The Kaplan-Meier method was used to evaluate the progression-free survival (PFS) and overall survival (OS) of patients, and the log-rank test was used for inter-group comparison.Results:Among NHL patients with HBV positive, 27 cases (33.8%) were EBV-positive and 29 cases (36.3%) were HBV reactivation. Compared with the EBV-negative group, the proportion of patients with Ann Arbor stage Ⅲ-Ⅳ [92.6% (25/27) vs. 66.0% (35/53)], elevated β 2-microglobulin level [88.9% (24/27) vs. 62.3% (33/53)], bone marrow involvement [40.7% (11/27) vs. 15.1% (8/53)], and HBV reactivation [51.9% (14/27) vs. 28.3% (15/53)] was higher in the EBV-positive group, and the differences were statistically significant (all P<0.05). There were no statistically significant differences in the composition of patients stratified by age, gender, pathological type, B symptom, lactate dehydrogenase level, international prognostic index score, number of extranodal involvements, liver involvement, hepatitis outbreak, prophylactic anti-HBV therapy, hepatitis B surface antibody (HBsAb), rituximab therapy, and the last chemotherapy effects between the 2 groups (all P > 0.05). Compared with the HBV non-reactivation group, the proportion of patients undergoing hepatitis outbreak [48.3% (14/29) vs. 17.6% (9/51)], not receiving prophylactic anti-HBV therapy [65.5% (19/29) vs. 39.2% (20/51)], HBsAb negative [79.3% (23/29) vs. 21.6% (11/51)], EBV positive [48.3% (14/29) vs. 25.5% (13/51)], receiving rituximab [82.8% (24/29) vs. 60.8% (31/51)] was higher in the HBV reactivation group, and the differenves were statistically significant (all P < 0.05); while there were no statistically significant differences in the composition of patients stratified by the other clinical characteristics between the 2 groups (all P > 0.05). Multivariate logistic regression analysis showed that EBV-positivity was an independent risk factor for HBV reactivation after chemotherapy in NHL patients with HBsAg positive ( OR = 7.073, 95% CI: 1.613-31.010, P = 0.009), while HBsAb positive ( OR = 0.038, 95% CI: 0.008-0.186, P < 0.001) and preventive anti-HBV therapy ( OR = 0.172, 95% CI: 0.039-0.756, P = 0.020) were independent protective factors. The last follow-up was in December 2023 and the median follow-up time was 36.5 months. There were no statistically significant differences in PFS and OS between the EBV-positive group and the EBV-negative group, HBV reactivation group and the non-reactivation group (all P > 0.05). Conclusions:Among HBV-infected NHL patients, those with concurrent EBV infection have a more advanced clinical stage and are very prone to bone marrow invasion, and they also show a higher probability of HBV reactivation; HBV reactivation may be related to whether receiving preventive anti-HBV therapy and rituximab therapy. EBV infection may increase the risk of HBV reactivation in NHL patients; EBV infection and HBV reactivation may not be relevant to the prognosis of patients.

Acute T-lymphoblastic leukemia (T-ALL) is a hematopoietic malignancy, and in recent years, with the advancement of combined chemotherapy and hematopoietic stem cell transplantation, the prognosis of T-ALL has improved significantly, but for patients with primary drug resistance or relapsed/refractory disease the prognosis is still poor. The plant homeodomain finger 6 (PHF6) is a tumor suppressor protein, it plays a pivotal role in T cell differentiation, epigenetic regulation and oncogenic pathway synergy, and its mutations and deletions are commonly associated with the development of T-lymphocytic leukemia. However, the underlying mechanism of PHF6 in the pathogenesis of T-ALL remains unclear. This article reviews the structure, function and mechanism of action of PHF6 in T-ALL, the important coexisting genes associated with the progression of T-ALL, and the research progress in targeted therapy.

Objective:To investigate the safety and therapeutic effect of split liver transplantation (SLT) in clinical application.Methods:This is a retrospective case-series study. The clinical data of 203 consecutive SLT, 79 living donor liver transplantation (LDLT) and 1 298 whole liver transplantation (WLT) performed at the Third Affiliated Hospital of Sun Yat-sen University from July 2014 to July 2023 were retrospectively analyzed. Two hundred and three SLT liver grafts were obtained from 109 donors. One hundred and twenty-seven grafts were generated by in vitro splitting and 76 grafts were generated by in vivo splitting. There were 90 adult recipients and 113 pediatric recipients. According to time, SLT patients were divided into two groups: the early SLT group (40 cases, from July 2014 to December 2017) and the mature SLT technology group (163 cases, from January 2018 to July 2023). The survival of each group was analyzed and the main factors affecting the survival rate of SLT were analyzed. The Kaplan-Meier method and Log-rank test were used for survival analysis.Results:The cumulative survival rates at 1-, 3-, and 5-year were 74.58%, 71.47%, and 71.47% in the early SLT group, and 88.03%, 87.23%, and 87.23% in the mature SLT group, respectively. Survival rates in the mature SLT group were significantly higher than those in the early SLT group ( χ2=5.560, P=0.018). The cumulative survival rates at 1-, 3- and 5-year were 93.41%, 93.41%, 89.95% in the LDLT group and 87.38%, 81.98%, 77.04% in the WLT group, respectively. There was no significant difference among the mature SLT group, the LDLT group and the WLT group ( χ2=4.016, P=0.134). Abdominal hemorrhage, infection, primary liver graft nonfunction,and portal vein thrombosis were the main causes of early postoperative death. Conclusion:SLT can achieve results comparable to those of WLT and LDLT in mature technology liver transplant centers, but it needs to go through a certain time learning curve.

Objective:To investigate the safety and therapeutic effect of split liver transplantation (SLT) in clinical application.Methods:This is a retrospective case-series study. The clinical data of 203 consecutive SLT, 79 living donor liver transplantation (LDLT) and 1 298 whole liver transplantation (WLT) performed at the Third Affiliated Hospital of Sun Yat-sen University from July 2014 to July 2023 were retrospectively analyzed. Two hundred and three SLT liver grafts were obtained from 109 donors. One hundred and twenty-seven grafts were generated by in vitro splitting and 76 grafts were generated by in vivo splitting. There were 90 adult recipients and 113 pediatric recipients. According to time, SLT patients were divided into two groups: the early SLT group (40 cases, from July 2014 to December 2017) and the mature SLT technology group (163 cases, from January 2018 to July 2023). The survival of each group was analyzed and the main factors affecting the survival rate of SLT were analyzed. The Kaplan-Meier method and Log-rank test were used for survival analysis.Results:The cumulative survival rates at 1-, 3-, and 5-year were 74.58%, 71.47%, and 71.47% in the early SLT group, and 88.03%, 87.23%, and 87.23% in the mature SLT group, respectively. Survival rates in the mature SLT group were significantly higher than those in the early SLT group ( χ2=5.560, P=0.018). The cumulative survival rates at 1-, 3- and 5-year were 93.41%, 93.41%, 89.95% in the LDLT group and 87.38%, 81.98%, 77.04% in the WLT group, respectively. There was no significant difference among the mature SLT group, the LDLT group and the WLT group ( χ2=4.016, P=0.134). Abdominal hemorrhage, infection, primary liver graft nonfunction,and portal vein thrombosis were the main causes of early postoperative death. Conclusion:SLT can achieve results comparable to those of WLT and LDLT in mature technology liver transplant centers, but it needs to go through a certain time learning curve.

Objective:To understand the use of post-exposure prophylaxis (PEP) and analyze related factors among men who have sex with men (MSM) in Qingdao, and provide a reference for the AIDS prevention and control in this population.Methods:A cross-sectional survey conducted from April 2022 to February 2023. Relying on MSM social groups in Qingdao, a snowball sampling method was applied to recruit research subjects who met the inclusion criteria of age ≥18 years old, having had homosexual anal or oral sex in the past six months, and HIV-negative or infection status unknown. The sample size was estimated at 566. Data on demographic characteristics, sexual behavior characteristics, PEP use, and others of the research subjects was collected through on-site questionnaires. The logistic regression model was used to analyze the factors associated with using PEP.Results:A total of 811 participants were recruited, mainly aged 25-34 (53.6%, 435/811), unmarried (74.7%, 606/811), with an average monthly income of ≥5 000 yuan (52.2%, 423/811), and having lived in Qingdao for ≥10 years (75.6%, 613/811). The proportion of those who knew the HIV status of their sexual partners in the last six months was 67.1% (544/811), and those with HIV-positive partners were 3.6% (29/811). In the last six months, the proportion of participants who had group sex (86.4%, 701/811), unprotected anal sex (98.2%, 796/811), and use of club drugs (80.3%, 651/811) was high. Moreover, 28.4% (230/811) had used PEP. The multivariate logistic regression analysis showed that the factors related to the use of PEP included divorced or widowed (a OR=5.46,95% CI:1.96-15.17), average monthly income ≥5 000 yuan (a OR=2.04,95% CI:1.44-2.89), same-sex sexual orientation (a OR=0.40,95% CI:0.22-0.71), having HIV-positive sexual partners in the last six months (a OR=2.54,95% CI:1.13-5.71) and having been tested for HIV ≥3 times in the last six months (a OR=1.46,95% CI:1.04-2.06). Conclusions:The prevalence of risk behaviors among MSM in Qingdao was high, and the use of PEP was low. In the future, it is essential to increase HIV/AIDS prevention education among MSM, promote MSM to know the HIV status of their sexual partners, and reduce the prevalence of risk behaviors among this population. Additionally, explore medical insurance reimbursement plans for PEP to reduce utilization costs and promote the use of PEP by MSM after HIV exposure occurs as soon as possible.

Objective:To investigate the differences in dosimetric impacts of the systematic errors induced by the leaf positions of a multi-leaf collimator (MLC) on the volumetric modulated arc therapy (VMAT) for patients with different T stages of nasopharyngeal carcinoma (NPC).Methods:A total of 44 patients with T 1-4N 1M 0 NPC were selected to design the VMAT plans using the Pinnacle planning system as the initial plans. The prescribed doses to the primary gross tumor volume (PGTV) were 68-70 Gy in 33 fractions for patients with T 1 and T 2 stage NPC and 71 Gy in 33 fractions for patients with T 3 and T 4 stage NPC. The prescribed doses to other target volumes were identical. In the initial plan files, a systematic error ranging from ±0.2 to ±1 mm was introduced to the position of each MLC leaf, leading to an increase or decrease in the subfield area. Then, potential error plans at the positions of MLC leaves during VMAT treatment were simulated. Dose evaluation indices involved target volumes and organs at risk (OARs). The indices related to target volumes consisted of the D98% of PGTV and PGTVnd, while those concerning OARs included the D0.1 cm 3 of the brainstem, spinal cord, and optic chiasm. Results:After the systematic errors induced by the positions of MLC leaves were introduced, the sensitivity range of each dose index range was (3.87%-9.87%)/mm ( R2 = 0.932-0.998, P < 0.01). Specifically, patients with stage T 4 NPC displayed higher sensitivity to the D98% of PGTV than those with stage T 1, T 2 and T 3 NPC ( Z = -3.12, -2.86, -2.59, P < 0.05), patients with stage T 3 NPC exhibited lower sensitivity to the D0.1 cm 3 of optic chiasm than those with stage T 1 and T 2 NPC ( Z = -2.92, -2.72, P < 0.05), and patients with stage T 4 NPC manifested lower sensitivity to the D0.1 cm 3 of chiasma than those with stage T 1 and T 2 NPC ( Z = -3.51, -3.25, P < 0.05). The relationship between the sensitivity of MU/Gy and PGTV D98% was y=-3.020+ 0.025 x ( r = 0.80, P < 0.05). Conclusion:The MU/Gy in the plans increased with the T stage of NPC, and the D98% of PGTV was more significantly affected by the systematic errors induced by the positions of MLC leaves. After the systematic errors induced by the positions of MLC leaves were introduced into the VMAT plans, doses to patients with T 4 stage NPC changed more significantly than those to patients with other T stages of NPC. Therefore, stricter quality control of leaf positions is required for patients with T 4 stage NPC, and it is recommended that the systematic errors should be less than 0.42 mm.