CT Study Of Primary Liver Cancer With Pulmonary Metastases

Objective: To retrospectively analyze the incidence and CT features of pulmonary metastases of primary liver cancer,and provide reliable basis for clinical diagnosis.Materials and method: From January 2013 to December 2014,total of 4268 patients with primary liver cancer confirmed by surgery and pathology were collected from our hospital.The incidence of lung metastasis of primary hepatocellular carcinoma(HCC)was about 8.06%(344/4268).Among them,97 cases of lung metastases were confirmed by 1-4times follow up,including 85 males and 12 females,aged from 21 to 76,with an average age of 48.5 years.The number and distribution of metastatic lesions were observed by conventional pulmonary window and mediastinal window,and the edge,shape and internal structure,density and enhancement of the lesions were evaluated.To analyze and compare the CT imaging features and follow up changes of different types of liver cancer with lungs metastases.Result: 1)primary tumor: In this study,97 cases of primary liver cancer,with size from 1cm-23 cm,the most common one with huge type of hepatocellular carcinoma(59 cases,60.82%),followed by mixed type of hepatocellular carcinoma(18 cases,18.56%),diffuse type of hepatocellular carcinoma(6 cases,6.85%),nodular type of hepatocellular carcinoma(14 cases.14.43%).Of which16 cases was complicated with portal vein tumor thrombus(16.49%,maximum),whereas 6 cases of inferior venacava,4 cases of hepatic vein and 2 cases of superior mesenteric vein tumor thrombi.The incidence of lung metastasis from primary liver cancer was about 8.06%(344/4268).2)Distribution of lungs metastases: multiple metastatic tumor were most frequently seen in 53 patients,54.64%),followed by diffuse metastasis in(27patients,27.83%)and solitary metastasis in(17 patients,17.52%).Most of the metastatic tumors were located in the lower lobes of the lungs,and mostly seen in peripheral side.3)The size,shape and boundary of lungs metastases: In this study of lungs metastases,tumor sized range from 0.1~3cm,mostly nodular type were seen in(86 patients,88.66%),followed by circular type in(40 cases,41.24%),soft tissue mass were seen in(9 patients,9.27%).boundary was smooth in most of the cases(93 patients,95.88%),and a few of the patients presented with blurred edges(4cases,4.12%).4)Density and Enhancement patterns of lungs metastases: In maximum cases of CT scan showed homogeneous density(92 cases,94.85%),and few cases presented with heterogeneous density(5 patients,5.15%)and in metastatic lesions cavity were seen in(1patient 1%).A total of 65 cases underwent enhanced scan,mild enhancement were mostly seen in(26 patients,40%), obvious enhancement seen in(26patients,40%),and moderate enhancement seen in(4patients,6.15%)and no enhancement were seen in 9 patients.5)Follow up: 23 cases were diagnosed as HCC with lungs metastases at the same time,whereas 74 cases were diagnosed first as HCC then diagnosed as lung metastases during follow up periods.Follow up was done 1-3 times,times duration was from 1-24 months.The majority of lung metastases showed an increased in size and numbers whereas few cases were found to have decreased in size,number,and few cases lesions was unchanged.6)The characteristics of lung metastases in patients with hepatocellular carcinoma(HCC)complicated with tumor thrombus: Pulmonary metastasis of portal vein tumor thrombus and other tumor thrombus is common in multiple metastases,and few in solitary and diffuse metastasis.7)Pulmonary and extrapulmonary signs associated with lung metastasis:pulmonary associated signs include pleural effusion(30 cases,30.93%),pneumothorax(2 cases,2.06%),pleural nodules(4 cases,4.12%),enlarged hilar lymph node(6 cases,6.18%)and mediastinal lymph node enlargement(7 cases,7.23%);most common extra pulmonary metastasis was lymph node metastases(18 cases,18.56%),followed by adrenal(n = 3)and spleen(n = 1).Conclusion: 1)In primary Liver cancer with lung metastasis,most common types of HCC is of huge type and most of them are complicated with portal vein tumor thrombus.2)The characteristics of HCC with lungs metastasis are as follows: both lungs have multiple nodular lesions,with different size,well-defined nodules,homogeneous density,and mild and severe enhancement,mostly seen in lower lobes of the lungs with peripheral distribution.3)Most of the metastatic tumors size and number were increased at the time of follow-up,accompanied by other signs of intra pulmonary and extra pulmonary metastasis.