Solid-pseudopapillary tumor of the pancreas: clinical features, pathological characteristics, and origin.
OBJECTIVE
[corrected] To study clinically pathological features and origin of solid-pseudopapillary tumor of pancreas (SPT).


METHODS
Clinical and pathological data of 82 cases with SPT were retrospectively studied. SAS6.12 statistics package was used for analysis. P < 0.05 was regarded as statistically significant difference.


RESULTS
The SPT patients included 70 females and 12 males, with a median age of 31 years old. The mean tumor size was 6.71 ± 4.42 cm. Vascular or organs was invaded in nine cases. The clinical and pathological characteristics show no significant difference between male and female patients. In the non-encapsulate group (22 cases), the tumor was larger (P = 0.0015), exogenous growth pattern (P = 0.0194), and would probably involve major vascular or organs (P = 1.697E-06). The typical features of SPT include pseudopapillary pattern with fibro vascular stalks by uniform poorly cohesive polygonal cells. The tumor cell expresses a variety of immune markers in heterogeneity. Under electron microscope, there are some electron dense granules, about 8-1.2 µm in diameter, with membrane similar to the zymogen granules in SPT cell cytoplasm.


CONCLUSIONS
SPT with incomplete capsule often presents malignant behaviors. SPT shows multi-heterogeneity, which is caused by the disorder in the development of pancreatic stem cell.
Department of General Surgery, Institute of Digestive Surgery, Ruijin Hospital, Shanghai JiaoTong University Medical college, Shanghai, China.
Jinhua
J
Ye
Mingzhe
M
Ma
Dongfeng
D
Cheng
Fei
F
Yuan
Xiaxing
X
Deng
Qian
Q
Zhan
Baiyong
B
Shen
Chenghong
C
Peng
D000328:Adult; D002291:Carcinoma, Papillary / Q000401:mortality / Q000473:pathology* / Q000628:therapy; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D046529:Microscopy, Electron, Transmission; D008875:Middle Aged; D010190:Pancreatic Neoplasms / Q000401:mortality / Q000473:pathology* / Q000628:therapy; D011379:Prognosis