Clinical Features And Survival Analysis Of 32 Cases Of Primary Parathyroid Carcinoma

BackgroundParathyroid carcinoma(PC)is a very rare malignant tumor,accounting for about 0.005%of all cancers.Therefore,it is challenging to study the clinical characteristics of PC.The clinical characteristics,standard treatment modality,and prognostic factors of PC patients are still unclear.ObjectiveThis study aimed to explore the clinical characteristics,therapeutic models,and prognostic factors of PC based on large sample data and data from our center,and evaluate the possibility of surviving for several additional years on the basis of surviving for a certain period of time.MethodsWe had analyzed the clinical data of PC patients registered in the SEER(Surveillance Epidemiology and End Result)database from 1975 to 2017,and analyzed the clinical data of PC patients diagnosed and treated in the First Affiliated Hospital of Zhengzhou University from June 2013 to January 2020,in order to explore the incidence trend,clinicopathological characteristics and prognostic factors of PC.SEER*Stat 8.3.8 and Joinpoint Regression 4.8.0.1 software were used to analyze the incidence trend of PC,and R-4.0.3 and GraphPad Prism 8 software were applied to survival analysis and conditional survival probability calculation.Kaplan-Meier was adopted to draw the survival curve,the Cox model was applied to analyze the survival-related prognostic factors,and the Log-rank test was used to detect the survival difference between different groups.Conditional survival(CS)rate is directly calculated on the basis of the existing survival time;Conditional survival calculation formula is CS=S(X+Y)/S(X),X is the survival time,Y is the additional survival time.Results1.Age-adjusted incidence trend in PCFrom 1992 to 2000,the annual percent change(APC)of the age-adjusted incidence of PC in American men was 13.41%(P<0.05).From 2000 to 2017,the age-adjusted incidence of PC in American men was-4.18%(P<0.05);but from 1992 to 2017,the age-adjusted incidence of PC in American women was 0.74%(P>0.05).2.Clinical features and prognostic analysis in PC based on the SEER databaseA total of 652 PC patients from the SEER database met our inclusion criteria,and 38(5.83%)PC patients had distant metastases.The median follow-up time for PC was 85.5 months.During the follow-up period,a total of 226 PC patients(34.66%)died.The overall median survival time was 210 months(95%Cl:191-249 months),and the 5-year overall survival(OS)rate was about 82.9%.Cox regression analysis showed that age,race,distant metastasis,and surgical status were prognostic factors for PC patients.3.Clinical features and prognostic analysis in PC based on the data from our centerAmong the 32 cases of PC patients diagnosed and treated in the First Affiliated Hospital of Zhengzhou University,seven patients progressed and four cases died.And we found that the 5-year progression-free survival(PFS)rate was 62.6%,5-years OS rate was 83.3%for PC patients,and PC patients with local tumor invasion or distant metastasis had shorter PFS and OS time.4.Conditional survival in PC based on the SEER databaseThe 5-year conditional survival rate increased with the prolonged survival time.In addition,younger patients with early stage have a better 5-year conditional survival rate.Conclusion1.From 2000 to 2017,the age-adjusted incidence of PC in American men has decreased year by year;however,from 1992 to 2017,the age-adjusted incidence of PC in American women has not changed.2.Age,race,distant metastasis,and surgery are the prognostic factors in PC patients.3.The 5-year conditional survival probability increase with the prolonged survival time.