The incidence of digestive system diseases is high. So digestive system pathology is widely concerned. In the past 10 years, Chinese pathologists insist on hard work and have made significant progress. This article reviews the research and practice progress in digestive system tumors and non-tumors in the past 10 years, including the establishment of diagnostic criteria for gastrointestinal tract, hepatobiliary and pancreatic diseases, the establishment and classification of new diseases with special morphology, the classification and standard update of gastrointestinal and pancreatic neuroendocrine tumors, the progress of molecular pathology, and non-tumor lesions of the digestive system. The future development trend of digestive system pathology is also prospected.

The incidence of digestive system diseases is high. So digestive system pathology is widely concerned. In the past 10 years, Chinese pathologists insist on hard work and have made significant progress. This article reviews the research and practice progress in digestive system tumors and non-tumors in the past 10 years, including the establishment of diagnostic criteria for gastrointestinal tract, hepatobiliary and pancreatic diseases, the establishment and classification of new diseases with special morphology, the classification and standard update of gastrointestinal and pancreatic neuroendocrine tumors, the progress of molecular pathology, and non-tumor lesions of the digestive system. The future development trend of digestive system pathology is also prospected.

Objective:To analyze the differences in clinicopathological features of colon cancers and survival between patients with right- versus left-sided colon cancers.Methods:This was a retrospective cohort study. Information on patients with colon cancer from January 2016 to August 2020 was collected from the prospective registry database at Peking Union Medical College Hospital . Primary tumors located in the cecum, ascending colon, and proximal two‐thirds of the transverse colon were defined as right-sided colon cancers (RCCs), whereas primary tumors located in the distal third of the transverse colon, descending colon, or sigmoid colon were defined as left‐sided colon cancers (LCCs). Clinicopathological features were compared using the χ 2 test or Mann‐Whitney U test. Survival was estimated by Kaplan‐Meier curves and the log‐rank test. Factors that differed significantly between the two groups were identified by multivariate survival analyses performed with the Cox proportional hazards function. One propensity score matching was performed to eliminate the effects of confounding factors. Results:The study cohort comprised 856 patients, with TNM Stage I disease, 391 (45.7%) with Stage II, and 336 (39.3%) with Stage III, including 442 (51.6%) with LCC and 414 (48.4%) with RCC and 129 (15.1%). Defective mismatch repair (dMMR) was identified in 139 patients (16.2%). Compared with RCC, the proportion of men (274/442 [62.0%] vs. 224/414 [54.1%], χ 2=5.462, P=0.019), body mass index (24.2 [21.9, 26.6] kg/m 2 vs. 23.2 [21.3, 25.5] kg/m 2, U=78,789.0, P<0.001), and well/moderately differentiated cancer (412/442 [93.2%] vs. 344/414 [83.1%], χ 2=22.266, P<0.001) were higher in the LCC than the RCC group. In contrast, the proportion of dMMR (40/442 [9.0%] vs. 99/414 [23.9%], χ 2=34.721, P<0.001) and combined vascular invasion (106/442[24.0%] vs. 125/414[30.2%], χ 2=4.186, P=0.041) were lower in the LCC than RCC group. The median follow‐up time for all patients was 48 (range 33, 59) months. The log‐rank test revealed no significant differences in disease-free survival (DFS) ( P=0.668) or overall survival (OS) ( P=0.828) between patients with LCC versus RCC. Cox proportional hazards model showed that dMMR was significantly associated with a longer DFS (HR=0.419, 95%CI: 0.204?0.862, P=0.018), whereas a higher proportion of T3‐4 (HR=2.178, 95%CI: 1.089?4.359, P=0.028), N+ (HR=2.126, 95%CI: 1.443?3.133, P<0.001), and perineural invasion (HR=1.835, 95%CI: 1.115?3.020, P=0.017) were associated with poor DFS. Tumor location was not associated with DFS or OS (all P>0.05). Subsequent analysis showed that RCC patients with dMMR had longer DFS than did RCC patients with pMMR (HR=0.338, 95%CI: 0.146?0.786, P=0.012). However, the difference in OS between the two groups was not statistically significant (HR=0.340, 95%CI:0.103?1.119, P=0.076). After propensity score matching for independent risk factors for DFS, the log‐rank test revealed no significant differences in DFS ( P=0.343) or OS ( P=0.658) between patients with LCC versus RCC, whereas patient with dMMR had better DFS ( P=0.047) and OS ( P=0.040) than did patients with pMMR. Conclusions:Tumor location is associated with differences in clinicopathological features; however, this has no impact on survival. dMMR status is significantly associated with longer survival: this association may be stronger in RCC patients.

Objective:To analyze the differences in clinicopathological features of colon cancers and survival between patients with right- versus left-sided colon cancers.Methods:This was a retrospective cohort study. Information on patients with colon cancer from January 2016 to August 2020 was collected from the prospective registry database at Peking Union Medical College Hospital . Primary tumors located in the cecum, ascending colon, and proximal two‐thirds of the transverse colon were defined as right-sided colon cancers (RCCs), whereas primary tumors located in the distal third of the transverse colon, descending colon, or sigmoid colon were defined as left‐sided colon cancers (LCCs). Clinicopathological features were compared using the χ 2 test or Mann‐Whitney U test. Survival was estimated by Kaplan‐Meier curves and the log‐rank test. Factors that differed significantly between the two groups were identified by multivariate survival analyses performed with the Cox proportional hazards function. One propensity score matching was performed to eliminate the effects of confounding factors. Results:The study cohort comprised 856 patients, with TNM Stage I disease, 391 (45.7%) with Stage II, and 336 (39.3%) with Stage III, including 442 (51.6%) with LCC and 414 (48.4%) with RCC and 129 (15.1%). Defective mismatch repair (dMMR) was identified in 139 patients (16.2%). Compared with RCC, the proportion of men (274/442 [62.0%] vs. 224/414 [54.1%], χ 2=5.462, P=0.019), body mass index (24.2 [21.9, 26.6] kg/m 2 vs. 23.2 [21.3, 25.5] kg/m 2, U=78,789.0, P<0.001), and well/moderately differentiated cancer (412/442 [93.2%] vs. 344/414 [83.1%], χ 2=22.266, P<0.001) were higher in the LCC than the RCC group. In contrast, the proportion of dMMR (40/442 [9.0%] vs. 99/414 [23.9%], χ 2=34.721, P<0.001) and combined vascular invasion (106/442[24.0%] vs. 125/414[30.2%], χ 2=4.186, P=0.041) were lower in the LCC than RCC group. The median follow‐up time for all patients was 48 (range 33, 59) months. The log‐rank test revealed no significant differences in disease-free survival (DFS) ( P=0.668) or overall survival (OS) ( P=0.828) between patients with LCC versus RCC. Cox proportional hazards model showed that dMMR was significantly associated with a longer DFS (HR=0.419, 95%CI: 0.204?0.862, P=0.018), whereas a higher proportion of T3‐4 (HR=2.178, 95%CI: 1.089?4.359, P=0.028), N+ (HR=2.126, 95%CI: 1.443?3.133, P<0.001), and perineural invasion (HR=1.835, 95%CI: 1.115?3.020, P=0.017) were associated with poor DFS. Tumor location was not associated with DFS or OS (all P>0.05). Subsequent analysis showed that RCC patients with dMMR had longer DFS than did RCC patients with pMMR (HR=0.338, 95%CI: 0.146?0.786, P=0.012). However, the difference in OS between the two groups was not statistically significant (HR=0.340, 95%CI:0.103?1.119, P=0.076). After propensity score matching for independent risk factors for DFS, the log‐rank test revealed no significant differences in DFS ( P=0.343) or OS ( P=0.658) between patients with LCC versus RCC, whereas patient with dMMR had better DFS ( P=0.047) and OS ( P=0.040) than did patients with pMMR. Conclusions:Tumor location is associated with differences in clinicopathological features; however, this has no impact on survival. dMMR status is significantly associated with longer survival: this association may be stronger in RCC patients.

In recent years, with being gradually developed, three-dimensional (3D) reconstruction based on pathology and medical imaging technology has shown certain value in the diagnosis and treatment of breast cancer. And with its advantages of providing the spatial location, morphological structure and 3D structure relationships with the surrounding tissues and organs, 3D reconstruction technology has played a key role in the early diagnosis, surgical treatment, and accurate evaluation of the treatment effect after surgery of breast cancer. Although the application of 3D reconstruction technology based on pathology and medical imaging is still inadequate, with the continuous development of science and technology, 3D reconstruction technology will play an increasingly important role in the diagnosis, personalized treatment and prognosis assessment of breast cancer.

Objective    To evaluate the prognosis of interventional treatment with covered stent graft for retrograde Stanford type A aortic dissection and intramural hematoma by single-arm meta-analysis. Methods    Related studies on treating retrograde Stanford type A aortic dissection and intramural hematoma with covered stent graft were retrieved from the databases by computer, including PubMed, EMbase, The Cochrane Library, Wanfang Data, VIP, CNKI and CBM, from inception to January 2020. Literatures were screened by researchers step by step according to the predefined inclusion and exclusion criteria. Quality of the enrolled literatures was evaluated, and data were extracted from the included studies. Afterwards, single-arm meta-analysis was carried out by the R3.6.3 software. Results    A total of 12 English and 5 Chinese studies were included, which were all case series, and the quality of all literatures was moderate evaluated by Newcastle-Ottawa Scale (NOS). After analyzing the clinical prognosis of 260 patients, the 30-day mortality was 6% (95%CI 0.04 to 0.11, P=0.97), the late mortality was 8% (95%CI 0.05 to 0.14, P=0.78), the incidence of endoleak was 21% (95%CI 0.16 to 0.29, P=0.06), the incidence of stroke was 5% (95%CI 0.03 to 0.09, P=0.99), the incidence of new aortic dissection was 7% (95%CI 0.04 to 0.11, P=0.96), the incidence of dissection progression was 10% (95%CI 0.07 to 0.16, P=0.24), and the absorption rate of intramural hematoma was 84% (95%CI 0.37 to 1.00, P<0.01). Conclusion    Interventional treatment with covered stent graft for retrograde Stanford type A aortic dissection and intramural hematoma can obtain good early treatment results for some patients, and can be used as a safe and effective treatment for aged patient with high risk who cannot tolerate surgery. Endoleak, stroke and new aortic dissection are the early serious complications of this method.

Objective To evaluate the diagnostic performance of diffusion kurtosis imaging (DKI) and its combination with DWI and proton MR spectroscopy (1H-MRS) in differentiating malignancy from benign breast lesions. Methods Fifty-three patients with 38 histopathologically confirmed malignant and 15 benign breast lesions were retrospectively studied. The patients were examined by breast MRI at 3.0 T prior to operation, including conventional T1WI, fat-suppression imaging, DWI, DKI and 1H-MRS. The shape and margin of breast lesions, and their corresponding mean values for ADC, mean kurtosis (MK) and mean diffusivity (MD) were determined by two blinded radiologists in consensus. The presence or absence of choline (Cho) peak was identified using LCModel software. Independent-samples t test or χ2 test was performed for the comparison of clinical characteristics, shape and margin of lesions, and imaging parameters between malignancy and benign lesions. ROC analysis was performed to evaluate the diagnostic accuracy of DKI, DWI and 1H-MRS alone or in combination, in comparison with the histopathologic findings. Results The onset age of breast malignancy was higher than that of benign ones, and the difference has statistical significant (P<0.05). Malignant lesions were most often seen in postmenopausal women, with unclear margin. There was no significant differences for body mass index (BMI), fiber type, the size and shape of lesions between benign lesions and malignancy (P>0.05). The mean ADC,MD and MK of benign lesions were(1.464 ± 0.348)× 10-3mm2/s,(1.726 ± 0.268)× 10-3mm2/s and(0.692 ± 0.227), the mean ADC,MD and MK of malignancy were(0.963 ± 0.170)× 10-3mm2/s,(1.158 ± 0.262)× 10-3mm2/s and(1.311 ± 0.218), respectively. Significant differences were obtained between benign and malignant lesions for all parameters (P<0.05).The area under the ROC curve (AUC) of ADC, MD and MK for differentiating malignancy from benign lesions was 0.913, 0.933 and 0.968, respectively. Taken the maximum Youden's index of MK (1.110) as the ROC optimal cut-off point, MK exhibited better diagnostic sensitivity, specificity and accuracy for distinguishing malignancy from benign lesions [89.5%(34/38),93.3%(14/15) and 90.6%(48/53), respectively], compared with MD and ADC. Multiparametric imaging with combination of DKI, DWI and 1H-MRS improves the diagnostic specificity (with the highest as 100.0%) but decreases the sensitivity (with the highest as 81.6% and lowest as 71.1% ), compare with the single parametric imaging. Conclusions MK generated from DKI enables differentiation of breast lesions with a higher diagnostic sensitivity and specificity than DWI and 1H-MRS. DKI combined with DWI and 1H-MRS increase specificity but decrease sensitivity for breast cancer characterization.

OBJECTIVETo evaluate the accuracy and clinical significance of clinical complete response (cCR) after neoadjuvant themoradiotherapy for locally advanced rectal cancer.

METHODSLocally advanced rectal cancer patients who received neoadjuvant chemoradiotherapy following radical resection were retrospectively assessed for tumor response during 2005 to 2014 from the database of colorectal cancer. The concomitant preoperative chemoradiation consisted of 50 Gy radiation, fractionated within 5 weeks and 5-FU combined with oxaliplatin. Endorectal ultrasound and MRI were applied to preoperative staging, and postoperative gross pathologic inspection was retrospectively employed to evaluate the status of clinical complete response(cCR).

RESULTSA total of 227 patients undergoing radical surgery were enrolled in the study. Complete pathological response (ypT0N0, pCR) was found in 40 patients(17.6%) by postoperative pathologic examination while the rate of node involved in ypT0 patients was 11.1%. The preoperative rectal MRI was more sensitive to correlate ypT0 than endorectal ultrasound and gross pathologic inspection(60.0% vs 19.4% and 17.8%), but the accuracy and specificity showed no significant differences among these three tests. Multivariate Logistic regression analysis revealed preoperative MRI evaluation of cT0 might predict ypT0 independently(OR=4.975, 95% CI: 1.073 to 23.067, P=0.040).

CONCLUSIONIt is difficult to diagnose the primary tumor to be a cCR status based on preoperative MRI, EUS, or ulceration of rectal mucosa, and further to predict pCR. Preoperative MRI is more sensitive. The strategy of "wait and see" for cCR patients after neoadjuvant chemoradiation should be seriously considered in the decision-making before surgery.

Chemoradiotherapy ; Fluorouracil ; Humans ; Magnetic Resonance Imaging ; Neoadjuvant Therapy ; Neoplasm Staging ; Postoperative Period ; Preoperative Period ; Rectal Neoplasms ; Remission Induction ; Retrospective Studies ; Treatment Outcome

Objective To evaluate the accuracy and clinical significance of clinical complete response (cCR) after neoadjuvant themoradiotherapy for locally advanced rectal cancer. Methods Locally advanced rectal cancer patients who received neoadjuvant chemoradiotherapy following radical resection were retrospectively assessed for tumor response during 2005 to 2014 from the database of colorectal cancer. The concomitant preoperative chemoradiation consisted of 50 Gy radiation , fractionated within 5 weeks and 5-FU combined with oxaliplatin. Endorectal ultrasound and MRI were applied to preoperative staging, and postoperative gross pathologic inspection was retrospectively employed to evaluate the status of clinical complete response (cCR). Results A total of 227 patients undergoing radical surgery were enrolled in the study. Complete pathological response (ypT0N0, pCR) was found in 40 patients (17.6%) by postoperative pathologic examination while the rate of node involved in ypT0 patients was 11.1%. The preoperative rectal MRI was more sensitive to correlate ypT0 than endorectal ultrasound and gross pathologic inspection (60.0% vs 19.4% and 17.8%), but the accuracy and specificity showed no significant differences among these three tests. Multivariate Logistic regression analysis revealed preoperative MRI evaluation of cT0 might predict ypT0 independently (OR=4.975, 95% CI: 1.073 to 23.067, P=0.040). Conclusion It is difficult to diagnose the primary tumor to be a cCR status based on preoperative MRI, EUS, or ulceration of rectal mucosa, and further to predict pCR. Preoperative MRI is more sensitive. The strategy of “wait and see”for cCR patients after neoadjuvant chemoradiation should be seriously considered in the decision-making before surgery.

Objective To evaluate the accuracy and clinical significance of clinical complete response (cCR) after neoadjuvant themoradiotherapy for locally advanced rectal cancer. Methods Locally advanced rectal cancer patients who received neoadjuvant chemoradiotherapy following radical resection were retrospectively assessed for tumor response during 2005 to 2014 from the database of colorectal cancer. The concomitant preoperative chemoradiation consisted of 50 Gy radiation , fractionated within 5 weeks and 5-FU combined with oxaliplatin. Endorectal ultrasound and MRI were applied to preoperative staging, and postoperative gross pathologic inspection was retrospectively employed to evaluate the status of clinical complete response (cCR). Results A total of 227 patients undergoing radical surgery were enrolled in the study. Complete pathological response (ypT0N0, pCR) was found in 40 patients (17.6%) by postoperative pathologic examination while the rate of node involved in ypT0 patients was 11.1%. The preoperative rectal MRI was more sensitive to correlate ypT0 than endorectal ultrasound and gross pathologic inspection (60.0% vs 19.4% and 17.8%), but the accuracy and specificity showed no significant differences among these three tests. Multivariate Logistic regression analysis revealed preoperative MRI evaluation of cT0 might predict ypT0 independently (OR=4.975, 95% CI: 1.073 to 23.067, P=0.040). Conclusion It is difficult to diagnose the primary tumor to be a cCR status based on preoperative MRI, EUS, or ulceration of rectal mucosa, and further to predict pCR. Preoperative MRI is more sensitive. The strategy of “wait and see”for cCR patients after neoadjuvant chemoradiation should be seriously considered in the decision-making before surgery.