Long-Term Effect Of Treatment Of Midface Tumors

Part Ⅰ Local recurrence of midfacial neoplasmsObjective:To evaluate the incidence of locally recurrence midfacial neoplasms and to determine the clinical features and risk factors associated with the locally recurrence midfacial tumors.Methods:A total of 327 patient records with midfacial neoplasms who received treatment from 2010 to 2018 in Department of Oral and Maxillofacial Surgery,Peking University School and Hospital of Stomatology were reviewed.The three-dimensional image of the tumor is divided into 6 aspects:superior,inferior,anterior,posterior,medial and lateral.The incidence of local recurrence was recorded according to the 6 aspects.Clinical features associated with the local recurrence were also documented.All data was analyzed using SPSS 19.0.Results:The midfacial neoplasm local recurrence rate was 32.8%.Local recurrence rate was observed to be highest in sarcoma,55.9%(38/68),followed by adenoid cystic carcinoma(ACC),45.9%(39/85);squamous cell carcinoma(SCC),19.3%(26/135)and ameloblastoma,10.3%(4/39).These rates were significantly different between each histopathological type(P<0.001).The incidence of local recurrence of SCC and sarcoma was highest during the first year postoperatively.While the recurrence rates of ACC and ameloblastoma varied from 1 to 10 years.Among the 107 patients with local recurrence,most frequent sites of recurrence were superior aspect,followed by medial and lateral.Sarcomas were observed to have more recurrence at superior and lateral aspects.SCC recurred at medial and lateral aspects more commonly and recurrence rate was significantly higher in T3/4 patients as compared to T1/2 patients.ACC predominantly recurred at the superior and medial aspects and presence of nerve invasion and tumor size were associated with the local recurrence rate(P=0.01,P=0.035).Ameloblastoma recurred mostly along the maxillary bone and superior,lateral and posterior aspects were observed most frequently.The recurrence rate after extended resection is 2.9%(1/34),which is significantly lower than the curettage(60.0%,3/5).Conclusions:Most frequent sites of local recurrence in midfacial neoplasms were superior aspect,followed by medial and lateral.High local recurrence rates were observed in sarcoma and ACC.Tumor size was associated with recurrence of ACC and SCC while nerve invasion was associated with recurrence of ACC.The recurrence rate of ameloblastoma is significantly lower if a radical approach is used.Part Ⅱ Predictive factors for long term survival in oral maxillary squamous cell carcinoma(SCC)Objective:We aim to evaluate the long-term survival rate and to determine the associated prognostic factors in oral maxillary SCC.This study also aims to explore the relationship between the tumor size and defect types using Brown’s maxillary defects classification and lastly to assess the local recurrence rate and long-term survival in different maxillary defect types.Methods:The clinical data of 137 patients with oral maxillary SCC from 2000 to 2010 were reviewed and 105 patients were followed up.The preoperative tumor size(AJCC TNM staging)and postoperative maxillectomy classification were recorded.The relationship between the classification of maxillectomy defect and T grade of oral maxillary SCC,the correlation between classification of maxillectomy defects and local recurrence rate and survival rate were analyzed using SPSS 19.0.Results:The most common maxillectomy defect type was class IIb,54.7%(75/137).Classification of maxillectomy defect was statistically significant with the increase of T grade(P<0.001).There was no significant correlation between classification of maxillectomy defect and local recurrence and neck metastasis(P=0.831,P=0.266).Cervical lymph node metastasis(P<0.001),vestibular sulcus invasion(P=0.002),local and regional recurrence(P=0.001,P<0.001)are all prognostic-related risk factors.Both T grade and classification of maxillectomy defect have the correlation with the survival rate of the patients with maxillary SCC(P=0.003,P<0.001).Conclusions:The predictive factors of long-term survival rate in oral maxillary SCC is associated with tumor recurrence and neck metastasis.Brown,s class Ⅱb maxilla defect was most frequently seen following maxillectomy.Types of maxillectomy defect were associated with the tumor size(T grade)and long-term survival rate.Brown’s classification of maxillectomy defects is simpler and more straightforward as compared to the TNM staging in daily clinical practice.Part Ⅲ Long-term effect of individualized titanium mesh in orbital floor reconstruction after maxillectomyObjective:The aim of this study was to determine the clinical outcomes and long-term stability of individualized titanium mesh combined with free flap for orbital floor reconstruction after maxillectomy and to identify the risk factors for titanium mesh exposure.Material and Methods:The data of 66 patients who underwent maxillectomy and orbital floor defect reconstruction by individualized titanium mesh in Peking University School and Hospital of Stomatology between 2011 and 2019 were reviewed retrospectively.Postoperative ophthalmic function and aesthetic outcomes were assessed.Titanium mesh exposure was recorded and the potential risk factors were identified.Results:The mean follow-up period was for 24.8 months(range,6-92 months).Ophthalmic functions were successfully restored in 95.5%patients(63 out of 66 patients)whilst 10 out of 66 patients were unsatisfied with the aesthetic outcomes.Titanium mesh exposure occurred in 6 patients(exposure rate,9.1%).Preoperative radiotherapy was identified as an independent risk factor for mesh exposure(OR=28.8,P=0.006).Previous surgery,postoperative radiotherapy,pathological type of the primary lesion,the type of tissue flap,and the use of intraoperative navigation were not significant risk factors.Six patients with titanium mesh exposure underwent second surgery,but mesh exposure recurred in two patients due to insufficient soft tissue coverage.Conclusion:Individualized titanium mesh with free flap can effectively restore maxilla-orbital defects.Preoperative radiotherapy is an independent predictor of postoperative titanium mesh exposure.Adequate soft tissue coverage of the mesh may reduce the risk of mesh exposure.Part Ⅳ The clinical study of fat grafting to prevent the exposure of maxillary titanium meshObjective:To evaluate the effect and stability of fat grafting technique on the aesthetics outcomes following orbital floor reconstruction,and to explore the related treatment methods of fat grafting technique.Material and Methods:Patients who underwent globe-sparing maxillectomy and reconstruction with vascularized free flap and individualized titanium mesh between 2011 to 2020 were recruited.The patients were divided into 2 groups:experimental and controlled groups.In both groups,the patients received vascularized free flap reconstruction.In experimental group,the patients received fat graft transfer for titanium mesh coverage as opposed to the controlled group.The soft tissue thickness at the inner canthal,zygomatic and infraorbital region were measured at postoperative 6 months.Granular fat grafts were performed in patients with insufficient soft tissue coverage and in patients unsatisfied with the aesthetic outcomes.Results:A total of 41 patients were enrolled,and the average follow-up time was 30.3(6-96)months.Titanium mesh exposure occurred in 4 patients,the exposure rate was 9.8%(4/41),and preoperative radiotherapy was an independent influencing factor.There were 23 cases in the test group(intraoperative fat transplantation group)and 18 cases in the control group.The titanium mesh exposure rates were similar in both groups(8.7%and 11.1%).There is no significant difference in the minimum value of the soft tissue thickness on the surface of the titanium mesh.However,the proportion of malignant tumors and the proportion of preoperative or postoperative radiotherapy in the experimental group were significantly higher than those in the control group.Five patients underwent postoperative granular fat transplantation,and their soft tissue thickness and facial appearance were improved postoperatively.Conclusion:Intraoperative fat transplantation can effectively reduce the risk of titanium mesh exposure in high-risk patients,and improve the long-term stability of orbital floor repair and reconstruction.Epidermal and dermal layers might not be sufficient for titanium mesh coverage.Local irritants should be strictly avoided and granular fat transplantation can be performed if necessary to improve the overlying soft tissue coverage and to improve the aesthetic outcomes.