CT Evaluation Of Gastric Neuroendocrine Tumors:Relationships Between CT Features And Pathologic Classification And Survival Outcomes

Part 1 CT Evaluation of Gastric Neuroendocrine Tumors:Relationship between CTFeatures and WHO 2010 pathologic classificationObjectives To find out whether CT features can distinguish neuroendocrine tumors(NETs,G1/G2)from neuroendocrine carcinomas(NECs G3 tumors and mixed adenoneuroendocrine carcinomas)Material and methods 86 cases of pathologically proven G-NENs,including 17 cases of neuroendocrine tumors(NETs,G1and G2 tumors)and 70 cases of neuroendocrine carcinomas(NECs,G3 tumors and mixed adenoneuroendocrine carcinomas)were retrospectively studied.We analyzed demographic characteristics and CT various features of the primary tumor(tumor location,tumor size,boundary between tumor and surrounding tissue,growth pattern,ulceration,transmural invasion,areas of cystic change or necrosis,enhancement pattern),nodal status,and metastasis and compared these features with pathologic grading.Results There are 87 lesions in 86 patients and only one showed endocrine symptoms.Grade 1 tumors were found in 13 patients with 14 lesions,and G2 in 3 patients,G3 in 49 cases and 21 in mixed adenoneuroendocrine carcinomas.Of all the tumors 44 were located ingastric cardia,28 were located in the gastric body and 15 in gastric fundus.The CT features that favor NECs over NETs include larger tumor size(>3.0cm),poorly defined margin,transmural invasion,infiltrative growth,both intra-and extra luminal involvement,ulceration,heterogeneous enhancement and regional lymph node metastasis with p values<0.05,The CT features that do not distinguish between the two types of G-NENs include adjacent organ invasion,areas of cystic change or necrosis and distant organ metastasis,withp values>0.05.Conclusion CT can be useful in the classification of GE-NENs.Part 2 Prognostic value of CT findings to predict survival outcomes in patients with gastric neuroendocrine neoplasmsObjectives To evaluate the prognostic value of CT in predicting recurrence-free survival and overall survival in patients with gastric neuroendocrine neoplasms(G-NENs).Methods Between January 2010 and January 2017,altogether 80 patients who underwent preoperative CT and surgical resection for G-NENs were identified.We analyzed demographic characteristics and various CT features of the primary tumor(tumor location,tumor size,boundary between tumor and surrounding tissue,growth pattern,ulceration,transmural invasion,areas of cystic change or necrosis,enhancement pattern),nodal status,and metastasis.The log-rank statistics was used to determine the association between CT features and recurrence-free survival and overall survival.Results By log-rank statistics,we find that heterogeneous enhancement pattern and lymph node metastasis are associate with worse recurrence-free survival.Age(>61 years),tumor size(>4.5cm),surgical type(R2),heterogeneous enhancement pattern and lymph node metastasis are associate with worse overall survival.Conclusions CT can be useful in predicting the survival outcomes of GE-NENs patients.