ABSTRACT
Objective To identify the imaging features of pancreatic acinar cell carcinomas.Methods Eleven patients of pancreatic acinar cell carcinomas proven surgically and pathologically were included.We retrospectively evaluated the CT and MR findings including the location, size, shape, margin, necrosis , calcification, hemorrhage, enhancement degree, enhancement pattern, invasion to other organs, perilesional lymph nodes, metastasis, recurrence.Results The tumors were distributed in the head(n=4), body and tail(n=4),tail(n=3) of pancreas.The median tumor size was 97 mm(27 to 180 mm).Nine cases presented with a well-defined enhancing capsule.Tumor vessels could be seen in 9 cases.Seven cases were hypovascular while the other 4 were hypervascular.Different extents of necrosis could be seen in all masses as a swirling or cleft low density in the enhanced tumors, with an median of 10％ (2％ to 25％).The hypovascular masses more frequently demonstrated a lobulated tumor, heterogeneous enhancement pattern, with a larger necrotic component and were more common invasion to other organs.Conclusions Pancreatic acinar ccll carcinoma typically presents as a sizable pancreatic mass with a well-defined enhancing capsule.
ABSTRACT
Objective To clinically verify the rationality of evaluation standard of oropharynx involvement in the Chinese 2008 staging system for nasopharyngeal carcinoma (NPC).Methods 333 consecutive patients with newly diagnosed,untreated,and nonmetastatic NPC were included.All patients had an MRI examnation of the nasopharynx and neck.The status of oropharynx involvement were evaluated.Results Of the 333 patients with NPC,26 (7.8 ％) patients presented with oropharynx involvement.Tumor invasion into oropharynx was highly related to tumor invasion into nasal cavity,parapharyngeal space,skull base,medial pterygoid muscle,paranasal sinuses,intracalvarium and masticator space excluding medial pterygoid muscle (P ＜ 0.050).The oropharynx involvement was associated with poorer 5-year overall survival (OS) and distant failure-free survival (DFFS) (38.1％ vs 72.6 ％,P＜ 0.001 and 49.1％ vs 84.5 ％,P＜ 0.001,respectively).By multivariate analyze,it was observed that oropharynx involvement was a significant predictive factor for OS and DFFS (P ＜ 0.001,P ＜ 0.001).Significant differences were observed in the 5-year OS (38.1％ vs 80.9 ％,P ＜ 0.001) and DFFS rates (49.1％ vs 89.3 ％,P ＜ 0.001) between the patients with oropharynx involvement and stage T2 patients.Conclusions MRI-evidenced oropharynx involvement had a negative impact on OS and DFFS in NPC patients.The oropharynx involvement is associated with poorer 5-year OS and DFFS compared with stage T2.The evaluation standard of oropharynx involvement for NPC in the Chinese 2008 staging system could be revised.