Histological Risk Factors for Lymph Node Metastasis in pT1 Colorectal Cancer:Does Submucosal Invasion Depth Really Matter?

Objective After endoscopic resection of colorectal cancer with submucosal invasion(pT1 CRC),additional surgical treatment is recommended if deep submucosal invasion(DSI)is present.This study aimed to further elucidate the risk factors for lymph node metastasis(LNM)in patients with pT1 CRC,especially the effect of DSI on LNM.Methods Patients with pT1 CRC who underwent lymph node dissection were selected.The Chi-square test and multivariate logistic regression were used to analyze the relationship between clinicopathological characteristics and LNM.The submucosal invasion depth(SID)was measured via 4 methods and analyzed with 3 cut-off values.Results Twenty-eight of the 239 patients presented with LNM(11.7%),and the independent risk factors for LNM included high histological grade(P=0.003),lymphovascular invasion(LVI)(P=0.004),intermediate to high budding(Bd 2/3)(P=0.008),and cancer gland rupture(CGR)(P=0.008).Moreover,the SID,width of submucosal invasion(WSI),and area of submucosal invasion(ASI)were not significantly different.When one,two,three or more risk factors were identified,the LNM rates were 1.1%(1/95),12.5%(7/56),and 48.8%(20/41),respectively.Conclusion Indicators such as the SID,WSI,and ASI are not risk factors for LNM and are subjective in their measurement,which renders them relatively inconvenient to apply in clinical practice.In contrast,histological grade,LVI,tumor budding and CGR are relatively straightforward to identify and have been demonstrated to be statistically significant.It would be prudent to focus on these histological factors rather than subjective measurements.

Current indications for endoscopic submucosal dissection of early gastric cancer

The development of endoscopic treatment technology has further promoted the minimally invasive treatment of early gastric cancer(EGC).Endoscopic treatment has achieved better therapeutic effects in terms of safety and prognosis and is the preferred treatment method for patients who meet the indications for endoscopic treatment.However,the consequent problem is that some patients receiving endoscopic treatment may undergo non-curative resection,and the principle of follow-up management for non-curative resection patients deserves further attention.In addition,there are still debates on how to improve the accuracy of clinical staging,select a reasonable treatment method for patients who meet the expanded indications for endoscopic treatment,manage patients with positive endoscopic surgical margins,conduct research on function-preserving surgery,and manage the treatment of EGC under the current situation in China.Consequently,we aim to review current indications for endoscopic submucosal dissection of EGC in order to better inform treatment options.

Malignant tumors associated with Peutz-Jeghers syndrome: Five cases from a single surgical unit

BACKGROUND Peutz-Jeghers syndrome(PJS) is an autosomal dominant inherited disease easily causing secondary malignant changes without effective treatments.AIM To assess the clinical characteristics, diagnosis, and treatment of malignant changes secondary to PJS.METHODS The clinical data of five patients with malignant changes secondary to PJS diagnosed and treated at Beijing Friendship Hospital from June 2014 to January 2017 were retrospectively analyzed;the follow-up ended in May 2018.RESULTS There were three male and two female patients with an average age of 43.6 years.Intestinal obstruction, intussusception, and abdominal pain were the first symptoms. Computed tomography and gastrointestinal imaging combined with endoscopy helped evaluate the depth of tumor infiltration and determine the need for radical resection. Three patients underwent surgery. Postoperative pathology confirmed adenocarcinoma, genetic test indicated STK11 mutation,and the patients received chemotherapy, including one who succumbed to tumor progression 6 months post-surgery. Other two patients underwent endoscopic resection, and postoperative pathology confirmed high grade intraepithelial neoplasia. The surviving patients had no recurrence by May 2018.CONCLUSION Endoscopy combined with computed tomography and gastrointestinal imaging is of great significance in the diagnosis and treatment of PJS, and pathological examination and gene detection are the gold standards for detecting malignant changes secondary to PJS. Some malignant polyps can be removed under endoscopy, and surgery is feasible when malignant polyps cannot be remove dunder an endoscope. For patients unable to achieve R0 resection, clinical symptoms should be relieved, and postoperative adjuvant chemotherapy could improve long-term prognosis. Meanwhile, close and regular surveillance should be conducted to prevent severe complications.

Coexistent Kaposi sarcoma and post-transplant lymphoproliferative disorder in the same lymph nodes after pediatric liver transplantation:A case report

BACKGROUND Kaposi sarcoma and post-transplant lymphoproliferative disorder have been occasionally reported in post-liver transplant patients.However,the simultaneous occurrence of these two diseases in the same lymph nodes is very rare.CASE SUMMARY We report the case of a 19-mo-old boy,who presented with intermittent fever and enlarged cervical lymph nodes after liver transplantation.Six cervical lymph nodes were biopsied,and the histopathological examinations revealed multifocal hyperplasia of spindle cells around small blood vessels,extravasated erythrocytes,and heavy infiltration of plasma cells in the cortex and medulla of the lymph nodes.The immunohistochemical analyses of spindle cells revealed positive expression of CD34,CD31,erythroblast transformation-specific-related gene,friend leukemia integration 1,and human herpesvirus-8.The lymphoproliferative lesions expressed CD38,CD138,and multiple myeloma 1.Epstein-Barr encoded RNA in situ hybridization demonstrated Epstein-Barr virus-positive lymphoid cells.Finally,we diagnosed the coexistence of Kaposi sarcoma and post-transplant lymphoproliferative disorder(plasmacytic hyperplasia)in the same lymph nodes.Treatment strategy included anti-CD20 monoclonal antibody(rituximab)and discontinuation of the immunosuppressant therapies.Lymph node biopsies during follow-up examinations revealed lymphoid hyperplasia.CONCLUSION The rare coexistence of Kaposi sarcoma and post-transplant lymphoproliferative disorder in the same lymph nodes post-liver transplantation possibly associates with immunodeficiency and Epstein-Barr virus and human herpesvirus-8 coinfection.

Mediastinum metastasis in a post-surgical pancreatic cancer patient successfully confi rmed with endoscopic ultrasonography

Dear editor,Pancreatic carcinoma is highly malignant and is mainly characterized by a low rate of eligibility for curative-intent resection,rapid metastases and/or local relapses even after surgery.[1-3]Imaging examinations like enhanced computed tomography(CT)/magnetic resonance imaging(MRI),and positron emission tomography-computed tomography(PET-CT),play an important role in detecting tumor recurrence or residual after radical resection of pancreatic cancer.However,these detection platforms are increasingly reported to have insufficient sensitivity and specificity.[4,5]Here we report a pancreatic cancer patient who had progressively increased carbohydrate antigen 19-9(CA199)level one year and three months after surgery;however,none of the above imaging methods were able to identify the cause.After our investigations,we discovered mediastinal metastasis using endoscopic ultrasonography(EUS)and confi rmed by EUS-guided fi ne needle aspiration(EUS-FNA).

Bladder paraganglioma after kidney transplantation:A case report

BACKGROUND Kidney transplantation is associated with an increased risk of tumors in the urinary bladder.Among all the pathological types of tumors in the bladder,paraganglioma,which arises from extra-adrenal paraganglia and consists of chromaffin cells,is rare.Paragangliomas might cause severe clinical symptoms due to catecholamine hypersecretion or mass compression.Bladder paragangliomas are rare,especially those appearing after kidney transplantation.Here,we report a case of bladder paraganglioma developing after kidney transplantation.CASE SUMMARY A 63-year-old woman received a kidney transplant 12 years ago and took oral immunosuppressants(cyclosporine,mizoribine,and methylprednisolone)for regular post-transplant treatment.The patient felt no discomfort and she came to the hospital for a routine checkup.A mass located in the bladder was incidentally discovered by computed tomography,and she underwent surgical treatment.A 2 cm×2 cm invasive mass was found in the trigone of the bladder and the mass was removed.The diagnosis of paraganglioma was confirmed by morphology and immunophenotyping.The patient had a good prognosis and is still alive.CONCLUSION Paraganglioma can grow in the bladder,which might cause no clinical symptoms.The diagnosis mainly depends on morphology and immunophenotyping.Surgical resection is an important treatment option for such patients.

Variable projection algorithms with sparse constraint for separable nonlinear models

Separable nonlinear models are widely used in various fields such as time series analysis, system modeling, and machine learning, due to their flexible structures and ability to capture nonlinear behavior of data. However, identifying the parameters of these models is challenging, especially when sparse models with better interpretability are desired by practitioners. Previous theoretical and practical studies have shown that variable projection (VP) is an efficient method for identifying separable nonlinear models, but these are based on \(L_2\) penalty of model parameters, which cannot be directly extended to deal with sparse constraint. Based on the exploration of the structural characteristics of separable models, this paper proposes gradient-based and trust-region-based variable projection algorithms, which mainly solve two key problems: how to eliminate linear parameters under sparse constraint;and how to deal with the coupling relationship between linear and nonlinear parameters in the model. Finally, numerical experiments on synthetic data and real time series data are conducted to verify the effectiveness of the proposed algorithms.