The Clinical Characteristics And Prognosis Of 234 Multiple Primary Cancer Patients

OBJECTIVEThe number of patients who suffered from multiple primary cancer(MPC)was increasing year by year.Previous clinical studies were limited by small sample size and few prognostic factors.Moreover,most studies were devoted to studying risk factors,but the prognostic factors of multiple primary cancers were still unclear.This study was aimed to explore the clinical characteristics of multiple primary cancer and the prognostic factors through large sample size and more prognostic factors.Meanwhile,this study analyzed different subgroups of multiple primary cancer.METHODSThis study retrospectively analyzed the clinical data of 234 patients with multiple primary cancers from January 2006 to December 2017 at the Sir Run Run Shaw Hospital,Zhejiang University.The overall survival rate was calculated by Kaplan-Meier method.And the clinical parameters associated with survival were analyzed using Log-rank test.The Cox regression models was used to explore possible varieties that had affection to patients with multiple primary cancer.RESULTSOf the 234 patients with multiple primary cancer,169 were male patients and 65 were female patients.The male to female ratio was 2.6:1.The average age of female patients was younger than that of male patients.There were 214 cases of double primary cancers(DPC)(91.5%),and 20 cases(8.5%)of triplicate primary cancers(TPC)or more advanced cancers.The digestive system was the most common lesion location of multiple primary cancer in this study.Of the 234 patients,77(32.9%)patients' first and second primary cancer-foci were located in the same system,of which 61 were in digestive system.In this study,156 cases(66.4%)were synchronous multiple primary cancers(SMPC).The number was larger than that of metachronous multiple primary cancer(MMPC)patients.The first 5 years after the diagnosis of the first primary cancer was the peak period of the incidence.Survival analysis was performed on 194 patients.The overall 1-year,3-year,and 5-year survival rate was 76.5%,45.2%,and 33.8%,respectively.Univariate analysis showed that male,the second primary cancer lesion located in the digestive system,the higher stage of the first primary cancer,the higher stage of the second primary cancer,the lack of radical treatment for the first primary cancer,the lack of radical treatment for the the second primary cancer,and the smoking history were poor prognostic factors affecting overall survival.Multivariate regression analysis showed that smoking history(p=0.006)and second primary cancer without radical surgery(p<0.001)were independent adverse prognostic factors affecting the overall survival of multiple primary cancers.For patients with simultaneous multiple primary cancers,the 1-year and 3-year overall survival rates were 77.3%and 48.8%,respectively.Univariate analysis showed that the smoking history(p=0.023),the first primary cancer without radical surgery(p=0.009),and the second primary cancer without radical surgery(p=0.002)were independent adverse prognostic factors affecting overall survival of multiple primary cancers.The 1-year and 3-year survival rate of multiple primary cancers in patients with digestive system cancer was 73.4%and 38.3%,respectively.Multivariate regression analysis showed that the higher stage of second primary cancer(p<0.001)was an independent adverse prognostic factor affecting the overall survival of multiple primary cancers.CONCLUSIONThe male patients' morbidity was higher than that of the female patients.The female patients' age of onset was younger than that of the male patients.For the whole group,the second primary cancer without radical surgery was an independent risk factor affecting its prognosis.Therefore,for patients with multiple tumors,physicians should be very cautious in diagnosis.They should not arbitrarily diagnose the illness as advanced tumor so that the patients might miss the opportunity for radical surgery.After the diagnosis of the multiple primary cancer,surgery should be performed if possible.The smoking history was not only an important risk factor for the pathogenesis of multiple primary cancers,but also an important risk factor affecting the prognosis of multiple primary cancer.In the subgroup analysis,smoking was also a risk factor of simultaneous multiple primary cancers.Advocating universal smoking cessation was very meaningful.For people with multiple primary cancers who have risk factors,such as genetic susceptibility,they should quit smoking as soon as possible.For the patients whose first primary cancer-foci located in the digestive system,the second primary cancer stage was an independent factor affecting its prognosis.And there was no significant difference between stage ? and ?,while stages ? and ? were independent adverse prognostic factors for patients whose first primary cancer located in the digestive system.