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The aim of this paper is to prove a sufficient stochastic maximum principle for the optimal control of systems driven by normal martingales. We also show the relationship between stochastic maximum principle and dynamic programming in which the control of the jump size is essential and the corresponding Hamilton-Jacobi-Bellman (HJB) equation in this case is a mixed second-order partial differential-difference equation. As an application, we solve explicitly a mean-variance portfolio selection problem. [ABSTRACT FROM AUTHOR]

Objective: To investigate the efficacy of V-Y advancement flap with facial artery perforator for the repair of midface skin defects. Methods: A retrospective analysis was performed on 18 patients with facial skin cancer, including 11 males and 7 females, aged 65-83 years, who underwent the repair of midface skin defects using V-Y advancement flap with facial artery perforator in the Department of Head and Neck Surgery, Affiliated Cancer Hospital of Nantong University from January 2020 to April 2023. Medium, large or complex midface skin defects developed after surgical resections of the primary lesions. According to the defect site, size, location information of facial vessels, a V-Y advancement flap with appropriate shape was designed for each case. During the operation, the facial vessels and their perforators were retained in the pedicle of the flap, the facial nerve branches were dissected and protected, and the further denuded pedicle was determined according to actual amount of advancement. After the flap was advanced, the facial defect area was repaired without tension, and the anatomical positions and functions of the eyes, nose and mouth were restored as far as possible. Postoperative follow-ups were conducted to observe the survival rate of the flaps, postoperative complications, recurrences and metastases of tumors. Results: Midface defects of 3.0 cm×3.5 cm-6.5 cm×7.5 cm were observed after tumor resections, which involved one or more subregions. The sizes of the flaps were 3.5 cm×9.0 cm-7.0 cm×18.0 cm. All flaps were completely alive except for one with temporary local bruising. With following-up of 4-40 months, 5 of the 12 patients with lower eyelid and inner canthus invasions had lower eyelid ectropion, but no exposed keratitis was found; one case with poorly differentiated squamous cell carcinoma had lymph node metastasis in the submandibular region and underwent neck dissection again; no recurrence or metastasis occurred in the remaining cases. Conclusion: The V-Y advancement flap with facial artery perforator can be used to repair medium, large or complex midface skin defects, with a high survival rate, and the operation method is safe and reliable.

Objective: To investigate the main indications and prognosis of patients undergoing orbital exenteration (OE). Methods: It was a retrospective case series study. The medical records were collected of patients who underwent OE surgery at Beijing Tongren Hospital from January 2007 to December 2021, and their general information, tumor characteristics, lymph node metastasis, diagnosis and treatment, specific surgical techniques, pathological diagnosis and prognosis were analyzed. Kaplan-Meier survival curves were used to evaluate overall survival and recurrence-free survival. Results: A total of 147 patients were included, with a median age of 58 (48, 68) years. Among them, 82 patients (55.8%) were male and 65 (44.2%) were female, and all underwent unilateral OE. Five patients (3.4%) had benign lesions. Among the 142 patients with malignant tumors, conjunctival malignancies (37.3%) were the most common, followed by eyelid (29.6%), orbital (19.0%), and ocular (14.1%) malignancies. Among the 53 patients with conjunctival tumors, 38 (71.7%) had conjunctival melanoma and 14 (26.4%) had squamous cell carcinoma. Among the 42 patients with eyelid malignancies, 19 (45.2%) had sebaceous gland carcinoma and 16 (38.1%) had basal cell carcinoma. Among the 20 patients with ocular malignancies, 10 (50.0%) had choroidal melanoma and 9 (45.0%) had retinoblastoma. The most common pathological types among the 142 patients with malignant tumors were melanoma (51 cases, 35.9%), squamous cell carcinoma (20 cases, 14.1%), sebaceous gland carcinoma (19 cases, 13.4%), and basal cell carcinoma (16 cases, 11.3%). Of the 135 patients included in the survival analysis, all 5 patients with benign lesions were alive at the last follow-up. The median follow-up time for the 130 patients with malignant tumors was 6.9 (2.5, 6.9) years, ranging from 0.2 to 14.0 years. The overall survival rates at 1, 3, and 5 years after surgery were 90.9% (95 %CI : 85.8%-96.0%), 68.4% (95 %CI: 59.6%-77.2%), and 60.1% (95 %CI : 50.5%-69.7%), respectively. The recurrence-free survival rates of patients with and without lymph node metastasis before surgery were 57.6% and 56.7%, respectively ( OR =1.062, 95% CI : 0.525-2.148, P =0.864), and the overall survival rates were 61.5% and 57.7%, respectively ( OR =1.019, 95% CI : 0.512-2.033, P =0.957), with no significant differences both. The recurrence-free survival rates of patients with melanoma (47 cases) and non-melanoma (83 cases) were 40.4% and 67.5%, respectively ( OR =2.576, 95% CI : 1.390-4.775, P <0.001), and the overall survival rates were 42.6% and 67.5%, respectively ( OR =2.845, 95% CI : 1.549-5.225, P <0.001), with significant differences both. Conclusions: The primary indications for OE are malignant tumors of the conjunctiva and eyelids, with melanoma being the most common malignant tumor of the conjunctiva. Melanoma patients who undergo OE have a lower survival rate compared to other types of malignant tumors. Nevertheless, even in the presence of tumor lymph node metastasis, patients can achieve a relatively good prognosis through OE.

Objective: To investigate the causes,prevention and treatment of femoral artery puncture related complications caused by the application of resuscitative endovascular balloon occlusion of the aorta (REBOA) in the resection of pelvic and sacral tumors. Methods: Clinical data of 23 patients with femoral artery puncture related complications who received REBOA in the resection of pelvic and sacral tumors from August 2010 to August 2018 at the Musculoskeletal Tumor Center,Peking University People's Hospital were retrospectively analyzed.There were 8 males and 15 females,with the an age of (37.0±16.2) years (range:15 to 65 years).Arterial access via the Seldinger technique for REBOA was obtained in the right common femoral artery of 18 cases,and in the left of 6 cases.An arterial sheath with a diameter of 11 to 12 F(1 F≈0.33 mm) was used for the patient.The occurrence and treatment of postoperative complications were analyzed. Results: Acute femoral arterial thrombosis occurred in 18 patients,which was managed by open repair 48 hours postoperatively.Among the 349 patients admitted before 2015 who received hemostasis by compression after femoral artery sheath removal,12 patients (3.4%) developed acute femoral artery thrombosis.While the 476 patients admitted after 2015 who used a vascular stapler to close the femoral artery wound,6 patients (1.3%) developed acute femoral artery thrombosis.One case of retroperitoneal hematoma and 1 case of femoral pseudoaneurysm were found and surgically fixed.Postoperative follow-up was (40±18) months (range:13 to 108 months).Three cases with chronic lower extremity ischemia were confirmed by Doppler ultrasonography during 1 to 5 years follow-up.Two of them had minimal symptoms and denied further treatment,while the other one received femoral-femoral artery bypass surgery to restore distal flow for pain and numbness relief. Conclusions: Acute femoral arterial thrombosis was the most common femoral artery puncture.Technique refinement of REBOA,the use of percutaneous suture device and close follow-up can reduce the approach-specific complications,and help to detect and treat the complications timely,which may popularize the clinical application of REBOA.

Objective: To summarize the clinical features, treatment and prognosis of retinoblastoma (RB) patients in distant metastasis stage. Methods: Retrospective case series study. Clinical data of 24 cases (30 eyes) with diagnosis of distant metastasis stage RB were collected in pediatrics department of Beijing Tongren Hospital affiliated with Capital Medical University, from September 2005 to December 2013. In these cases, including 11 male cases and 13 female cases, the treatment age ranged from 7 months to 9 years with the median of 26 months. There were 18 unilateral cases (12 cases of right eye and 6 cases of left eye) and 6 bilateral cases. All cases were treated with surgery, chemotherapy and radiotherapy. The adverse reaction, blood routine and biochemical routine were monitored dynamically and regularly during treatment. The clinical manifestations and auxiliary examination were combined to evaluate the therapeutic effect. Determining the prognosis with death and survival, the survival curve and the median survival time were calculated by the product limit method. Results: The results of pathologic examination of 13 cases showed 11 cases of optic nerve involvement, 6 cases of optic nerve and choroid involvement, 1 case of post laminar involvement, 1 case of cornea and conjunctiva involvement. The most common metastatic site was central nerve system (CNS) (23 cases), followed by orbital involvement (10 cases). Other metastatic sites included bone (9 cases), bone marrow (1 case), pleura (1 case) and lymph node (1 case). 23 patients with CNS metastasis underwent systemic chemotherapy and intrathecal injection. The toxicity and side effects of radiotherapy and chemotherapy were evaluated and classified as grade I-II. Those adverse effects were tolerated by all cases. Followed up to December 31, 2015, all patients with CNS metastasis died and the median survival time was 6 months. Only 1 patient without CNS metastasis disease-free survived for 64 months. Conclusions: The most common metastasis site of RB was CNS. The overall prognosis of RB with distant metastasis was poor, in spite of given combined treatment mainly including surgery, chemotherapy and radiotherapy. But the prognosis of RB patients without CNS metastasis in distant metastasis stage was better than with CNS metastasis. (Chin J Ophthalmol, 2017, 53: 121-126) .

Objective: To observe the treatment and prognosis of choroid invasion of retinoblastoma (RB) in children. Method: A total of 149 children who had been diagnosed with unilateral RB and received enucleation disclosing tumor invasion to choroid from January 2006 to December 2013 in Beijing Tongren Hospital were recruited in this study. Choroid involvement was classified as massive choroid invasion and focal choroid invasion. Massive choroid invasion was defined as a maximum diameter of invasive tumor focus of 3 mm or more in diameter that might reach the scleral tissue. Focal choroid invasion was defined as a tumor focus of less than 3 mm in diameter without involvement of sclera. The treatment was delivered according to the invasive status of tumor with combination of histopathological high risk factors. The prognosis of different degrees of choroid invasion was observed. They were divided into two groups according to whether the merger of other high histopathologic risk factors, the survival situation was compared. The subjects were followed up for 1 to 9 years (the median follow-up time: 4 years and 1 month). Result: Among the 149 subjects, 90 were boys and 59 were girls. The right eye was affected in 81 patients and the left eye in 68 patients. Sixteen patients died, resulting in an overall survival rate of 89.3%. Among massive choroid invasion in 47 cases, 9 patients experienced disease recurrence and death resulting in a survival rate of 80.9%. While the focal choroid invasion was found in 102 cases, only 7 children had disease relapsed and died resulting in a survival rate of 93.1% which was statistically significant (χ 2 =5.067, P =0.024). Among 8 patients with massive choroid invasion without pathological high-risk factors, no death occurred, while in other 39 patients with high-risk factors, 9 died with a mortality rate of 23.1%, however, the difference was not statistically significant (Fisher's exact probability method, P =0.323). Among 60 patients with focal choroid invasion without pathological high-risk factors, no death was observed, while among the other 42 patients presenting high-risk factors, 7 of them died with a mortality rate of 16.7% (Fisher's exact probability method, P =0.003). Cox multivariate analysis showed that massive choroid invasion and surgical margin of the optic nerve were influential factors of prognosis. Conclusion: Patients with focal choroid invasion have a low disease recurrence and may not receive adjuvant chemotherapy. Patients with massive choroid invasion without presenting pathological high-risk factors warrant further prospective study to assess whether adjuvant chemotherapy is needed. However chemotherapy is recommended for those with massive choroid invasion presenting with risk factors to avoid the high disease recurrence in such patients.