Preoperative prediction of lymphovascular and perineural invasion in gastric cancer using spectral computed tomography imaging and machine learning

BACKGROUND Lymphovascular invasion(LVI)and perineural invasion(PNI)are important prognostic factors for gastric cancer(GC)that indicate an increased risk of metastasis and poor outcomes.Accurate preoperative prediction of LVI/PNI status could help clinicians identify high-risk patients and guide treatment deci-sions.However,prior models using conventional computed tomography(CT)images to predict LVI or PNI separately have had limited accuracy.Spectral CT provides quantitative enhancement parameters that may better capture tumor invasion.We hypothesized that a predictive model combining clinical and spectral CT parameters would accurately preoperatively predict LVI/PNI status in GC patients.AIM To develop and test a machine learning model that fuses spectral CT parameters and clinical indicators to predict LVI/PNI status accurately.METHODS This study used a retrospective dataset involving 257 GC patients(training cohort,n=172;validation cohort,n=85).First,several clinical indicators,including serum tumor markers,CT-TN stages and CT-detected extramural vein invasion(CT-EMVI),were extracted,as were quantitative spectral CT parameters from the delineated tumor regions.Next,a two-step feature selection approach using correlation-based methods and information gain ranking inside a 10-fold cross-validation loop was utilized to select informative clinical and spectral CT parameters.A logistic regression(LR)-based nomogram model was subsequently constructed to predict LVI/PNI status,and its performance was evaluated using the area under the receiver operating characteristic curve(AUC).RESULTS In both the training and validation cohorts,CT T3-4 stage,CT-N positive status,and CT-EMVI positive status are more prevalent in the LVI/PNI-positive group and these differences are statistically significant(P<0.05).LR analysis of the training group showed preoperative CT-T stage,CT-EMVI,single-energy CT values of 70 keV of venous phase(VP-70 keV),and the ratio of standardized iodine concentration of equilibrium phase(EP-NIC)were independent influencing factors.The AUCs of VP-70 keV and EP-NIC were 0.888 and 0.824,respectively,which were slightly greater than those of CT-T and CT-EMVI(AUC=0.793,0.762).The nomogram combining CT-T stage,CT-EMVI,VP-70 keV and EP-NIC yielded AUCs of 0.918(0.866-0.954)and 0.874(0.784-0.936)in the training and validation cohorts,which are significantly higher than using each of single independent factors(P<0.05).CONCLUSION The study found that using portal venous and EP spectral CT parameters allows effective preoperative detection of LVI/PNI in GC,with accuracy boosted by integrating clinical markers.

A novel tube for sperm density gradient centrifugation procedure

Objective:Density gradient centrifugation(DGC),swim up(SU),or a combination of DGC and SU is used to prepare sperm for infertility treatments using assisted reproductive technologies(ARTs).This study aimed to investigate the efficiency of a new device for detecting sperm DGC.Methods:Sperm samples were collected from 119 males who required semen analysis at three differentin vitro fertilization(IVF)centers(71 samples from Center A,28 samples from Center B,and 20 samples from Center C).Semen samples were divided into two groups for DGC:(1)a normal centrifugation tube and(2)a specially designed RC-Tube.The sperm concentration,motility,and DNA fragmentation index(DFI)were assessed using DGC.Sperm concentration and motility were assessed using a MAKLER counting chamber.Sperm DFI was measured and analyzed using flow cytometry using a DFI Kit.Results:There were no significant differences in sperm concentrations recovered following DGC between the two groups(31.1%±1.7%vs.28.8%±1.3%).Sperm motility was not significantly different following the DGC procedure in both groups(77.6%±1.6%.vs.75.8%±1.6%).The percentage of sperm DFI was also not significantly different following DGC between the two groups(10.4%±1.0%vs.10.5%±1.0%).Conclusions:The newly designed RC-Tube is efficient for sperm DGC and can be used to simplify sperm preparation for infertility treatment.

Changes in human sperm motility and DNA fragmentation index after incubation at different temperatures following density gradient centrifugation and swim-up procedures

Objective:The purpose of this study was to evaluate the sperm motility and DNA integrity at different temperatures to analyze whether the sperms are suitable on the second day for insemination of in vitro matured oocytes by intra-cytoplasmic sperm injection(ICSI)following density gradient centrifugation(DGC)and swim-up(SU)procedures.Methods:Semen samples were collected from 30 outpatients who visited the Center for Reproductive Medicine for semen analyses.Following sperm selection by DGC and SU procedures,the liquified semen samples were divided into three groups and incubated at 4,25,and 37°C,respectively.Following incubation for 24,48,and 72 hours,the sperm motility and sperm DNA fragmentation index(DFI)were analyzed.Results:Following the combination of DGC and SU procedures,the sperm motility(91.8%±8.6%vs.50.8%±13.1%)and DFI(5.1%±7.9%vs.13.0%±11.6%)were significantly improved(P<0.01)compared to those without any treatment.The sperm motility of the 3 groups significantly declined(P<0.05)post-incubation compared to that of the groups prior incubation.However,sperm motility significantly increased(76.9%±10.4%)(P<0.05)at 25°C compared to that of the other 2 groups(53.5%±11.0%and 47.6%±10.2%).Sperm DFI significantly increased(P<0.05)at 37°C following incubation for 24 and 72 hours in comparison to that of the other 2 groups.However,the sperm DFI did not significantly increase when the sperm samples were incubated at 4(5.7%±5.9%)and 25°C(6.8%±5.6%)for 24 hours compared to that before incubation(5.1%±7.9%).Conclusions:These results indicate that the sperm quality,in terms of motility and DFI,can be efficiently improved by DGC in combination with SU.Following which,the sperm samples can be incubated at 25°C and be used on the second day for insemination of in vitro matured oocytes by ICSI.

A nonobstructive azoospermic patient with Trichomonas vaginalis infection in testes

Dear Editor, Trichomonas vaginalis （ T. vaginalis）, a flagellated protozoan parasite emerged as one of the most common nonviral sexually transmitted infections worldwide, often inhabits the vagina, urethra, prostate, and epididymis.X It has been estimated that there are more than 170 million new cases of T. vaginalis infections per year worldwide. However, current knowledge of T. vaginalis and trichomoniasis is based mainly on studies in female vaginal infections. The prevalence of trichomoniasis in males is far less well characterized than that in females, probably because the infection seems to be asymptomatic in most men and can be resolved after treatment with one dose of metronidazole.