Analysis Of Clinical And Pathological Features And Prognostic Factors Of Extramammary Paget Disease

Background and objective: Extramammary Paget disease(EMPD)is a relatively rare,slow-growing cutaneous malignancy.The exact incidence and pathogenesis of EMPD are unknown,and no standardized guidelines for the treatment of EMPD have been established.Due to its low incidence,little is known about the diagnosis,treatment and prognosis of EMPD.Therefore,this study aims to explore the clinical and pathological characteristics,treatment,recurrence,survival rate and prognostic factors of EMPD,so as to improve the clinical diagnosis and treatment level of EMPDMethods: The clinical data of 29 patients with EMPD diagnosed in the first affiliated hospital of guangxi medical university and third affiliated hospital from January 2014 to December 2020 were collected.We retrospectively analyzed the gender,age,course of diseases,type of skin lesions,histopathological and immunohistochemical,serum CEA level,lymph node and distant metastasis,treatments,recurrence and prognosis of EMPD.The Kaplan-Meier curve was used to estimate the survival rate,and log-rank univariate analysis was performed for each factor.Results: Among the 29 patients,24 were males and 5 were females.The ratio of males to females was 4.8:1.Patients wre 51-to 92-year-old,with an average age of 66.55±9.61 years.The course of the disease ranged from 1 month to 12 years,with a mean of 48 months.The skin lesions usually occur in the genital area.The most common initial skin lesion is erythema,which is often accompanied by pruritus.The skin lesions are mainly manifested as erythema,plaque,erosion,ulcer,and exudation.The early misdiagnosis rate was 82.76%,and the most common misdiagnosis was eczema.Histopathology showed that the characteristic Paget cells were distributed in single or nested form in the middle and lower parts of the epidermis or in the entire layer,often involving hair follicles and sweat glands(65.52%),and 11 cases(37.96%)with tumor cells infiltrating the dermis.Immunohistochemistry CK7(18/18),EMA(15/15),CEA(13/13)were all positive,CK20 positive rate was 20.69%(6/29),GCDFP15 positive rate was 48.28%(14/29),CK20+/GCDFP15-in 3 cases;HER2 overexpression rate was 62.07%(18/29),of which 8 cases were 3+,10 cases were 2+,5 cases were 1+,and 6 cases were 0;The proportion of HER2 overexpression in invasive EMPD was significantly higher than that in non-invasive EMPD(P=0.019).There were 3 patients of lymph node metastasis and 2 patients of distant metastasis.Extended local excision in 8 patients,11 patients underwent extended local excision and intraoperative frozen section,surgical resection combined with photodynamic therapy in 6 patients,surgical resection combined with chemother-apy in 1 patients,radiotherapy in 1 patients,and 4 patients died.The disease-free survival time of 26 patients treated by surgery was 1-81 months,and the median disease-free survival time was 14.5 months.The 1,3 and 5-year disease-free survival rates estimated by K-M survival curve were 88.2%,58.8%and 29.4%,respectively.Recurrence occurred in 7 patients,the recurrence rate was 30.43%(7/23).The overall survival time of 29 patients was 1-92 months,with a mean of 29 months.The 1,3 and 5-year survival rates were 91.50%,84.90% and 74.30%.Univariate analysis showed that male,mixed Paget cell morphology and serum CEA level>5ng/ml may be the potential risk factors for postoperative recurrence,and Multi-site lesions,tumor invasion,lymph node metastasis,distant metastasis and serum CEA>5ng/ml were significantly associated with poor prognosis in EMPD.Conclusion: EMPD tends to occur in the genital area of elderly men.The early skin lesions lack specificity,the diagnosis is relatively difficult,and the misdiagnosis rate is high.The definite diagnosis depends on histopathology,and immunohistochemical examination can improve the diagnosis rate.The character-istic Paget cells in single or nested distribution in the epidermis can be seen under the microscope,often involving skin appendages,and can infiltrate the dermis;HER2 overexpression rate in EMPD is high,and it is related to tumor aggressive-ness.EMPD generally has a good prognosis,and surgical resection is the first choice for the treatment of EMPD;Paget cell morphology diversity and elevated serum CEA levels may be risk factors for postoperative recurrence.Multi-site lesions,tumor infiltration in the dermis,lymph node metastasis,distant metastasis,and elevated serum CEA levels are associated with poor prognosis.