Objective: To study the clinicopathological and immunohistochemical features, histogenesis and biological behavior, clinical treatment and prognosis of solid pseudopapillary tumor of the pancreas (SPT).
Methods: Routine HE and immunohistochemical (SP) stainings were used in the pathological examination of 18 cases of SPT. Their clinical data were retrospectively analyzed. All the 18 postoperative patients were followed-up for 3 months to 10 years with an average of 29.2 months.
Results: There were 16 females and 2 males, age ranging from 9 to 65 years with mean age of 25.3 years. Abdominal pain and palpable mass were among the major complains. Tumors were encapsulated and mixed with solid and cystic tissues. Histological features were pseudopapillary structure with a fibrovascular core. Immunhistologically, most tumors were positive for alpha-AT, alpha-ACT and Vim, with a high percentage of 94.4%. The eighteen cases were followed-up from 3 to 120 months. Five cases received reoperation after recurrence, and 14 cases were alive. Maximum survival time was 121 months and the minimum survival time was 3 months, with a median survival time of 23.0 months. The 5-year survival rate was 72.2%. A Kaplan-Meier analysis revealed that patient's age, tumor size, pathologic features, metastasis were major prognostic factors for SPT.
Conclusion: SPT is a tumor of low-grade malignancy and may be derived from multipotent stem cells. SPT most frequently affects young female, and has distinct clinicopathologic manifestation with excellent prognosis after surgical treatment.