Prognostic Analysis Of Postoperative Chemotherapy For Stage IB Lung Adenocarcinoma With A Micropapillary Pattern

Objective : The clinical factors that may affect the prognosis of pulmonary adenocarcinoma with a micropapillary pattern(MPPAC)in stage IB were analyzed to determine the correlation between postoperative adjuvant chemotherapy and prognosis.Meanwhile,it provides some references for the treatment and prognosis of patients with stage IB MPPAC after lung cancer surgery.Methods:A total of 112 patients who received surgical treatment for lung cancer in the department of thoracic surgery,the first affiliated hospital of Dalian medical university from December 2011 to December 2016 were collected.Moreover,the paraffin sections of the postoperative pathological tissues of all patients were confirmed to contain micropapillary pattern by two or more pathologists.The staging was classified as IB(T2a N0M0)according to TNM(Tumor Node Metastasis)staging method of 2018.v5 clinical practice guide for non-small cell lung Cancer(NSCLC)published by the National Comprehensive Cancer Network.According to the data statistics,the clinical data of the 112 patients were perfect,including the clinical factors such as whether to receive adjuvant chemotherapy,age,gender,tumor maximum diameter,smoking history,degree of differentiation,whether the visceral pleura was involved and the surgical method.The follow-up methods include phone calls,text messages,letters and visits,and the deadline is December 2019.All postoperative adjuvant chemotherapy regimens are based on platinum-based two-drug combined first-line chemotherapy regimens,ensuring at least 2 cycles of adjuvant chemotherapy.Using the SPSS25.0 statistical software to analyze the data,we found that the chi-square test was used for the difference of clinical factors between the postoperative adjuvant chemotherapy group and the non-adjuvant chemotherapy group.Kaplan-meier method was used for univariate analysis of prognosis,the 3-year overall survival rate and disease-free survival rate were obtained and the corresponding curves were drawn.Differences between groups were tested by log-rank method.Finally,COX proportional hazard model was used for multi-factor analysis to obtain the independent factors affecting the prognosis,and p value less than 0.05 was considered statistically significant.Results:All enrolled patients were collected strictly according to inclusion and exclusion criteria.Kaplan-meier analysis showed that Postoperative adjuvant chemotherapy(p=0.009)and the degree of tumor differentiation(p<0.001)were statistically significant for overall survival(OS)of stage IB MPPAC patients.Postoperative adjuvant chemotherapy(p=0.004),pathologic differentiation(p=0.004)and involvement of visceral pleura(p=0.018)were statistically significant in disease-free survival(DFS)of stage IB MPPAC patients.After chisquare test,there was no significant difference in clinical factors between the group receiving adjuvant chemotherapy and the group not receiving adjuvant chemotherapy,except gender.The 3-year overall survival rate(OS rate)of the group receiving adjuvant chemotherapy and the group not receiving adjuvant chemotherapy was 96.2% and 86.4%.The 3-year disease-free survival rate(DFS)of the group receiving adjuvant chemotherapy and the group not receiving adjuvant chemotherapy was 91.7% and 74.5%.Furthermore,the overall survival curve and disease-free survival curve of the group receiving adjuvant chemotherapy were significantly higher than that of the group not receiving adjuvant chemotherapy.The results of COX proportional hazard model and multifactor analysis suggested that postoperative adjuvant chemotherapy was correlated with overall survival(p=0.041)and disease-free survival(p=0.018),while the degree of tumor differentiation was only correlated with overall survival(p=0.008).Postoperative adjuvant chemotherapy was a protective factor for the prognosis of patients.Among the 112 patients included,there were 53 patients received postoperative adjuvant chemotherapy,accounting for 47.3% of the total,and 59 patients without adjuvant chemotherapy,accounting for 52.7% of the total.There were 16 patients with low differentiation of tumor tissue,accounting for 14.3% of the total,and 96 patients with medium and high differentiation,accounting for85.7% of the total.Postoperative pathological results showed that 102 patients(91.1%)were involved in the visceral pleura,and 10 patients(8.9%)were not involved in the visceral pleura.Conclusion:1.Postoperative adjuvant chemotherapy is a protective factor for the prognosis of patients with stage IB MPPAC,which can prolong the overall survival and disease-free survival of patients and improve the prognosis of patients significantly.2.the degree of tumor differentiation was an independent influencing factor for the overall survival of stage IB MPPAC patients,and the differentiation is lower,the prognosis is worse.