Cemental tear is a rare and indetectable condition unless obvious clinical signs present with the involvement of surrounding periodontal and periapical tissues. Due to its clinical manifestations similar to common dental issues, such as vertical root fracture, primary endodontic diseases, and periodontal diseases, as well as the low awareness of cemental tear for clinicians, misdiagnosis often occurs. The critical principle for cemental tear treatment is to remove torn fragments, and overlooking fragments leads to futile therapy, which could deteriorate the conditions of the affected teeth. Therefore, accurate diagnosis and subsequent appropriate interventions are vital for managing cemental tear. Novel diagnostic tools, including cone-beam computed tomography (CBCT), microscopes, and enamel matrix derivatives, have improved early detection and management, enhancing tooth retention. The implementation of standardized diagnostic criteria and treatment protocols, combined with improved clinical awareness among dental professionals, serves to mitigate risks of diagnostic errors and suboptimal therapeutic interventions. This expert consensus reviewed the epidemiology, pathogenesis, potential predisposing factors, clinical manifestations, diagnosis, differential diagnosis, treatment, and prognosis of cemental tear, aiming to provide a clinical guideline and facilitate clinicians to have a better understanding of cemental tear.
Humans ; Dental Cementum/injuries* ; Consensus ; Diagnosis, Differential ; Cone-Beam Computed Tomography ; Tooth Fractures/therapy*

Objective:To detect the association of tumor circumferential involvement range (CIR) with neoadjuvant chemoradiotherapy (NCRT) efficacy and long-term survival outcomes in locally advanced rectal cancer (LARC) patients.Methods:Clinical data of 451 patients admitted to our hospital from January, 2018 to January, 2022 were retrospectively collected. According to the CIRs as determined by rectal magnetic resonance imaging, patients were divided into the High group (≥2/3 cycle, 270 patients) and the Low group (＜2/3 cycle, 181 patients). The primary outcome was three-year disease-free survival. The baseline characteristics, pathological features, and survival outcomes were compared.Results:Compared to patients in the Low group, patients in the High group exhibited significantly larger tumor vertical diameters [(4.7±1.7) vs. (3.6±1.4)cm, P＜0.001], higher rates of mrT4 stage (37.8% vs. 13.2%, P＜0.001), and higher rates of positive mesorectal fascia (54.1% vs. 29.8%, P＜0.001) and extramural vascular invasion (55.6% vs. 38.1%, P＜0.001). Patients in the High group were mainly pT3-4 stages (46.7% vs. 30.9%, P=0.002), with significantly lower rates of pathological complete response (22.2% vs. 33.1%, P=0.010) , poorer tumor regression grades (48.9% vs. 60.8%, P=0.013), and higher rates of positive peripheral nerve invasion (11.5% vs. 5.5%, P=0.031), as compared to patients in the Low group. The median follow-up time was 40 months. About 11 (2.4%) and 48 patients (10.6%) experienced tumor local recurrence and distant metastasis, respectively. The recurrence rates were 2.2% and 2.6%, and the distant metastasis rates were 7.7% and 12.6%, respectively, in the Low group and the High group, with no statistical significance ( P=0.957, P=0.096). The three-year disease-free survival in the High group was significantly lower than that in the Low group (84.4% vs. 92.4%, P=0.014). Conclusions:The CIR is closely related to tumor burden, which can judge tumor response to NCRT, and is negatively related to survival prognosis. For patients who have more than a 2/3 cycle of CIR, intensified or consolidated treatments may be required to improve survival outcomes.

Background and Aims:For patients with mid-to-low rectal cancer who achieve clinical complete response(cCR)or near-cCR after neoadjuvant chemoradiotherapy(nCRT),the key concern for both clinicians and patients is how to preserve anal function as much as possible without significantly compromising oncological outcomes.This study was performed to evaluate the safety and feasibility of local excision as an anus-preserving approach in rectal cancer patients with cCR or near-cCR.Methods:A retrospective analysis was conducted on 51 patients with mid-to-low rectal cancer who underwent local resection after achieving cCR or near-cCR following nCRT at Peking Union Medical College Hospital,Chinese Academy of Medical Sciences,between March 2014 and July 2023.The clinical characteristics,imaging and pathological findings,surgical outcomes,as well as oncological and functional results were reviewed.Results:Among the 51 patients,34 were male and 17 were female,with a mean age of 61±14 years.Pre-nCRT imaging staging showed:cT1-2N0 in 12 cases(23.5％),cT3N0 in 13 cases(25.5％),cT1-3N0-1 in 19 cases(37.4％),and cT1-3N2 in 7 cases(13.7％).The average tumor distance from the anal verge was(4.5±1.1)cm.After achieving cCR or near-cCR following nCRT,all patients underwent local resection:40 cases(78.4％)underwent transanal endoscopic microsurgery(TEM),7 cases(13.7％)underwent transanal minimally invasive surgery(TAMIS),and 4 cases(7.8％)underwent conventional transanal local excision.The postoperative complication rate was 27.5％(14/51),with 71.4％classified as Clavien-Dindo grade Ⅰ.Postoperative histopathology showed ypT0 in 26 cases(51.0％),ypT1 in 8 cases(15.7％),ypT2 in 16 cases(31.4％),and ypT3 in 1 case(2.0％).The concordance rate between pathological results and preoperative imaging was 54.9％.Over a median follow-up of 60 months(range:34-79),there were 4 cases(7.8％)of local recurrence,12 cases(23.5％)of distant metastasis,and 5 cancer-related deaths(9.8％).Six months postoperatively,both the Wexner score and the low anterior resection syndrome(LARS)score significantly improved compared to post-nCRT values[Wexner:1(0-2)vs.2(1-5);LARS:3.3±5.75 vs.4.3±6.86;both P＜0.01].Conclusion:For patients with mid-to-low rectal cancer who achieve cCR or near-cCR after nCRT,local en bloc resection of the bowel wall lesions enables accurate assessment of residual tumor status and facilitates personalized subsequent treatment,potentially sparing some patients from radical surgery.Local resection can be a viable anus-preserving option for patients who are unfit for or strongly averse to radical resection.However,local excision cannot replace radical surgery,and its precise indications warrant further investigation.

Objective:To evaluate the clinical features and risk factors of anastomotic leakage (AL) in patients with locally advanced rectal cancer (LARC) receiving neoadjuvant chemoradiotherapy (nCRT) followed by laparoscopic radical resection and proctocol ostomy.Method:Clinicla data of LARC patients receiving neoadjuvant chemoradiotherapy followed by laparoscopic radical resection and proctocol ostomy admitted to Peking Union Medical College Hospital between Jan 2019 and Oct 2023 was enrolled. According to the occurrence of AL, patients were divided into AL group and non-AL group.Results:After propersity matching score(PSM), there were 40 patients (33.4%) and 80 patients (66.6%) in the AL and non-AL group, respectively. The first-onset symptoms of AL were abnormal character and color of the drainage (23 cases, 57.5%) and fever (14 cases, 35.0%). About 82.5% of the AL were graded as B,and all 36 patients (90.0%) were managed consveratively by fully drainage anti-infection therapy. Logistic regression analysis indicated that tumor circumferential range more than 1/2 cycle ( OR=5.95, 95% CI:2.12-1.67, P=0.004), male ( OR=4.28, 95% CI:1.22-15.00, P=0.023) and high-ligation of Inferior mesenteric artery ( OR=8.08, 95% CI:1.86-37.78, P=0.006) were independent risk factors of AL. Conclusions:In this series, grade-B AL ranks the top of the incidence, and all were cured by conservative therapy. Special attention should be paid to those patients with the characteristics of male, tumor circumferential range more than 1/2 cycle, and high-ligation of inferior mesenteric artery.

Background and Purpose:Neoadjuvant immunotherapy currently significantly enhances treatment efficacy for locally advanced rectal cancer(LARC);However,clinical management of immune-related adverse events(irAEs)lacks robust evidence.This study aimed to investigate the characteristics,clinical management strategies,and outcomes of irAEs during neoadjuvant immunotherapy for rectal cancer,providing a basis for optimizing irAEs monitoring and intervention.Methods:We retrospectively analyzed clinical data from LARC patients who developed irAEs after receiving neoadjuvant immunotherapy at Peking Union Medical College Hospital,Chinese Academy of Medical Sciences,between July 2022 and June 2024.Types of irAEs,severity,time of onset,management strategies,and outcomes were recorded.All patients underwent regular follow-up for at least 6 months.This study has been approved by Peking Union Medical College Hospital,Chinese Academy of Medical Sciences(ethical approval number:I-24PJ0024).Descriptive statistics were used to summarize irAEs patterns and management approaches.Results:A total of 41 irAE episodes occurred among the 30 patients.Mild irAEs(Grade 1-2)accounted for 78.0%(32/41),while severe irAEs(Grade 3-4)constituted 22.0%(9/41).Five patients(16.7%)permanently discontinued treatment due to severe toxicity.Endocrine toxicities were most frequent(36.6%,15/41),primarily characterized by progression from hyperthyroidism to hypothyroidism;75.0%required thyroid hormone replacement therapy.One case of delayed-onset adrenal insufficiency was alleviated with glucocorticoid(GC)therapy.Among hepatotoxicities(19.5%,8/41),62.5%were Grade 3 injury,and 37.5%required GC intervention;two patients experienced recurrence during adjuvant chemotherapy.Three cases of severe myositis occurred,accompanied by asymptomatic myocardial injury(evidenced by markedly elevated creatine kinase and concurrent changes in cardiac biomarkers),all requiring high-dose GC pulse therapy combined with intravenous immunoglobulin or immunosuppressants(recovery period:2-4 months).Nine dermatological reactions were managed with topical therapy.Two gastrointestinal events occurred,including one Grade 3 diarrhea treated with GCs.The overall GC usage rate was 31.7%(13/41),with 76.9%administered for Grade≥3 irAEs.Conclusion:irAEs during neoadjuvant immunotherapy for LARC are predominantly mild-to-moderate and manageable with supportive care.However,some patients develop severe(Grade 3-4)irAEs requiring multidisciplinary management.GC usage is concentrated in higher-grade irAEs,with severe myositis and cardiac involvement necessitating intensive immunosuppressive therapy despite their rarity.Recurrence of irAEs during adjuvant chemotherapy in a minority of patients underscores the necessity for early recognition,graded intervention,and comprehensive management throughout the entire treatment cycle.

Objective:To analyze the types and characteristics of post-operative complications in colorectal cancer patients aged over 85 years undergoing laparoscopic surgery, and to summarize peri-operative management strategies.Methods:This was an observational study. Inclusion criteria: pathologically confirmed adenocarcinoma; tumor located in ileocecum, ascending colon, transverse colon, descending colon, sigmoid colon, or rectum; undergoing laparoscopic radical resection for colorectal cancer; complete clinical data. Exclusion criteria included distant metastasis, synchronous resection of multiple primary cancers, simultaneous liver metastasis surgery, and follow-up duration <1 month. A retrospective analysis was conducted on 191 patients of colorectal cancer patients aged over 85 years who underwent laparoscopic radical surgery in the General Surgery Department at Peking Union Medical College Hospital from January 2019 to January 2024. Among 191 patients, 107 patients (56.0%) had colon cancer and 84 (44.0%) rectal cancer. All patients received "home-based prehabilitation" and post-operative "enhanced recovery after surgery" protocols. Patient characteristics, peri-operative complication types, treatments, and outcomes were analyzed.Results:Post-operative complications occurred in 97 patients (50.8%), including 53 colon cancer patients (54.6%) and 44 rectal cancer patients (45.4%). Comorbidities existed in 88 patients (90.7%), with 93 patients (95.9%) classified as ASA II-III pre-operatively and 86 (88.7%) having nutritional risks. Surgical procedures included Dixon procedure (38 patients, 39.2%), right hemicolectomy (33 patients, 34.0%), sigmoidectomy (10 patients, 10.3%), and 17 patients (17.5%) received prophylactic stomas. Complication types comprised non-anastomotic infections (38 patients, 19.9%), intestinal flora disorder (26 patients, 13.6%), anastomotic/wound/stoma-related complications (16 patients, 8.4%), thrombotic/hemorrhagic events (6 patients, 3.1%), and others (11 patients, 5.8%). By Clavien-Dindo classification: Grade I (12 patients, 6.3%), Grade II (69 patients, 36.1%), Grade III (12 patients, 6.3%), and Grade IV (4 patients, 2.1%). Except for 5 patients (2.6%) requiring unplanned re-operation, all complications resolved with conservative treatment. The median duration of post-operative hospitalization was 9.5 days (7–13).Conclusion:Non-anastomotic infections and intestinal flora disorder constitute predominant complications after laparoscopic surgery in colorectal cancer patients aged over 85 years, mostly manageable with conservative treatment. Strengthened peri-operative management incorporating pre-operative prehabilitation and post-operative enhanced recovery after surgery protocols is crucial for patients aged over 85 years.

Objective:To explore the application of the camera inversion technique in laparoscopic sphincter-preserving surgery for mid to low rectal cancer.Methods:A retrospective study with historical controls was conducted on patients with non-metastatic mid to low rectal cancer which received laparoscopic total mesorectal excision at Peking Union Medical College Hospital from January 2019 to June 2024. The experimental group (2021.7-2024.6) utilized the camera inversion technique (rotating the lens 180° to position the bevel upward and switching the system to reverse display mode for improved visualization and operative angles) during key surgical steps (such as intraoperative mobilization of the mid-to-lower rectum and anastomosis), while the control group (2019.1-2021.6) did not. Clinical data and surgical videos were collected to analyze indicators like operative time, blood loss, mesorectal integrity, surgical complications, and postoperative hospital stay.Results:A total of 624 patients with non-metastatic mid to low rectal cancer were included, including 412 males and 212 females, with an average age of 59.8 years and an average tumor distance of 5.6 cm from the anal verge. The experimental group comprised 301 patients, while the control group had 323 patients.The proportion of abdominal ISR (intersphincteric resection) was significantly higher in the experimental group [19.3% (58/301) vs. 10.2%(33/323), χ 2=10.140, P=0.001], with a reduction in operative time [(161.8±67.8) minutes vs. (150.2±68.5) minutes, t=2.134, P=0.033] and a decrease in postoperative hospital stay [(7.8±2.1) days vs. (8.3±3.4) days, t=2.003, P=0.046]. The experimental group also demonstrated advantages in intraoperative blood loss, mesorectal integrity rate, and postoperative complications such as urinary retention, though these differences were not statistically significant (all P>0.05). Conclusion:In laparoscopic surgery for mid to low rectal cancer, using camera inversion technique during distal rectum dissection and transanal anastomosis can provide better surgical field exposure, facilitate precise operations within the correct anatomical plane, and minimize collateral damage. The camera inversion technique is safe and effective.

Objective:To investigate the complications, along with their diagnosis and management, that follow local excision for rectal cancer after neoadjuvant therapy.Methods:The clinical data of 53 patients with rectal cancer who underwent local resection after neoadjuvant treatment in Peking Union Medical College Hospital from January, 2010 to December, 2024 were retrospectively collected for this descriptive case series study. Indications for local resection were: (1) age ≥ 18 years; (2) American Society of Anesthesiologists (ASA) classification I-III; (3) pathologically confirmed rectal adenocarcinoma; (4) distance from the lower edge of the tumor to the anal edge of less than 8 cm; and (5) use of preoperative neoadjuvant therapy. Contraindications of local resection were: (1) multiple primary colorectal cancer and (2) intestinal obstruction, intestinal perforation, or and gastrointestinal bleeding that required emergency surgery. There were 36 males and 17 females, and the median age was 62 (26-85) years. After neoadjuvant therapy, the median distance from the tumor to the anal margin was 4.5 (range, 2.2-6.9) cm. The main outcome measures included: surgical details, pathological findings, postoperative complications, anorectal function, and oncological outcomes (recurrence and survival).Results:Surgical methods included transanal endoscopic microsurgery (TEM) in 47 cases, transanal minimally invasive surgery (TAMIS) in 3 cases, and traditional transanal local resection in 3 cases. Of the 53 patients, 29 (54.7%) had pathological complete response (pCR), namely pT0 stage; 8 cases were pT1, 15 cases were pT2, and 1 case was pT3. Twenty-four cases (45.3%) had 33 complications. Clavien-Dindo grade I-II accounted for 97.0% (32/33), including 14 cases (26.4%) of wound dehiscence. Low anterior resection syndrome (LARS) occurred in 7 cases (13.2%), including 5 minor cases and 2 major cases. Postoperative fever occurred in 7 cases (13.2%); urinary retention occurred in 3 cases (5.7%); and diarrhea occurred in 1 case (1.9%). Clavien Dindo grade III was observed in only 3.0% (1/33) of patients, which was a rectovaginal fistula. Among the 14 patients with wound dehiscence, 7 cases only suffered anal pain and were cured after symptomatic analgesic treatment. Five cases suffered anal pain with hematochezia but improved after treatment with essential diet, hemostasis, intravenous antibiotics, pain relief, and sitz bath. Two cases of secondary perianal infection were treated with intravenous antibiotics, local drainage, parenteral nutrition support, and symptomatic treatment, and the wounds healed within 2 months. One patient with rectovaginal fistula underwent transverse colostomy. After six months, the fistula healed and stoma reversal was performed. Seven patients with LARS received anal lifting exercise and defecation reflex training, and anal function recovered to the preoperative level after 1 year. Other complications improved after symptomatic treatment, pain relief, or catheter replacement. The median follow-up time was 60 months. Local recurrence occurred in 4 patients (7.5%) and distant metastasis occurred in 12 patients (22.6%). Seven patients (13.2%) died. The 5-year disease-free survival rate was 75.5%, and the 5-year overall survival rate was 86.8%.Conclusions:Local excision for rectal cancer following neoadjuvant therapy has a high incidence of complications, mainly wound-related, due to the decline of rectal wound healing ability after radiotherapy. However, most of the complications were relieved after symptomatic treatment, and the risk was controllable.

Background and Purpose:Neoadjuvant immunotherapy currently significantly enhances treatment efficacy for locally advanced rectal cancer(LARC);However,clinical management of immune-related adverse events(irAEs)lacks robust evidence.This study aimed to investigate the characteristics,clinical management strategies,and outcomes of irAEs during neoadjuvant immunotherapy for rectal cancer,providing a basis for optimizing irAEs monitoring and intervention.Methods:We retrospectively analyzed clinical data from LARC patients who developed irAEs after receiving neoadjuvant immunotherapy at Peking Union Medical College Hospital,Chinese Academy of Medical Sciences,between July 2022 and June 2024.Types of irAEs,severity,time of onset,management strategies,and outcomes were recorded.All patients underwent regular follow-up for at least 6 months.This study has been approved by Peking Union Medical College Hospital,Chinese Academy of Medical Sciences(ethical approval number:I-24PJ0024).Descriptive statistics were used to summarize irAEs patterns and management approaches.Results:A total of 41 irAE episodes occurred among the 30 patients.Mild irAEs(Grade 1-2)accounted for 78.0%(32/41),while severe irAEs(Grade 3-4)constituted 22.0%(9/41).Five patients(16.7%)permanently discontinued treatment due to severe toxicity.Endocrine toxicities were most frequent(36.6%,15/41),primarily characterized by progression from hyperthyroidism to hypothyroidism;75.0%required thyroid hormone replacement therapy.One case of delayed-onset adrenal insufficiency was alleviated with glucocorticoid(GC)therapy.Among hepatotoxicities(19.5%,8/41),62.5%were Grade 3 injury,and 37.5%required GC intervention;two patients experienced recurrence during adjuvant chemotherapy.Three cases of severe myositis occurred,accompanied by asymptomatic myocardial injury(evidenced by markedly elevated creatine kinase and concurrent changes in cardiac biomarkers),all requiring high-dose GC pulse therapy combined with intravenous immunoglobulin or immunosuppressants(recovery period:2-4 months).Nine dermatological reactions were managed with topical therapy.Two gastrointestinal events occurred,including one Grade 3 diarrhea treated with GCs.The overall GC usage rate was 31.7%(13/41),with 76.9%administered for Grade≥3 irAEs.Conclusion:irAEs during neoadjuvant immunotherapy for LARC are predominantly mild-to-moderate and manageable with supportive care.However,some patients develop severe(Grade 3-4)irAEs requiring multidisciplinary management.GC usage is concentrated in higher-grade irAEs,with severe myositis and cardiac involvement necessitating intensive immunosuppressive therapy despite their rarity.Recurrence of irAEs during adjuvant chemotherapy in a minority of patients underscores the necessity for early recognition,graded intervention,and comprehensive management throughout the entire treatment cycle.

Background and Aims:For patients with mid-to-low rectal cancer who achieve clinical complete response(cCR)or near-cCR after neoadjuvant chemoradiotherapy(nCRT),the key concern for both clinicians and patients is how to preserve anal function as much as possible without significantly compromising oncological outcomes.This study was performed to evaluate the safety and feasibility of local excision as an anus-preserving approach in rectal cancer patients with cCR or near-cCR.Methods:A retrospective analysis was conducted on 51 patients with mid-to-low rectal cancer who underwent local resection after achieving cCR or near-cCR following nCRT at Peking Union Medical College Hospital,Chinese Academy of Medical Sciences,between March 2014 and July 2023.The clinical characteristics,imaging and pathological findings,surgical outcomes,as well as oncological and functional results were reviewed.Results:Among the 51 patients,34 were male and 17 were female,with a mean age of 61±14 years.Pre-nCRT imaging staging showed:cT1-2N0 in 12 cases(23.5％),cT3N0 in 13 cases(25.5％),cT1-3N0-1 in 19 cases(37.4％),and cT1-3N2 in 7 cases(13.7％).The average tumor distance from the anal verge was(4.5±1.1)cm.After achieving cCR or near-cCR following nCRT,all patients underwent local resection:40 cases(78.4％)underwent transanal endoscopic microsurgery(TEM),7 cases(13.7％)underwent transanal minimally invasive surgery(TAMIS),and 4 cases(7.8％)underwent conventional transanal local excision.The postoperative complication rate was 27.5％(14/51),with 71.4％classified as Clavien-Dindo grade Ⅰ.Postoperative histopathology showed ypT0 in 26 cases(51.0％),ypT1 in 8 cases(15.7％),ypT2 in 16 cases(31.4％),and ypT3 in 1 case(2.0％).The concordance rate between pathological results and preoperative imaging was 54.9％.Over a median follow-up of 60 months(range:34-79),there were 4 cases(7.8％)of local recurrence,12 cases(23.5％)of distant metastasis,and 5 cancer-related deaths(9.8％).Six months postoperatively,both the Wexner score and the low anterior resection syndrome(LARS)score significantly improved compared to post-nCRT values[Wexner:1(0-2)vs.2(1-5);LARS:3.3±5.75 vs.4.3±6.86;both P＜0.01].Conclusion:For patients with mid-to-low rectal cancer who achieve cCR or near-cCR after nCRT,local en bloc resection of the bowel wall lesions enables accurate assessment of residual tumor status and facilitates personalized subsequent treatment,potentially sparing some patients from radical surgery.Local resection can be a viable anus-preserving option for patients who are unfit for or strongly averse to radical resection.However,local excision cannot replace radical surgery,and its precise indications warrant further investigation.