Primary pancreatic tumors are rare in pediatric and adolescent patients. Our study showed outcomes of the largest series in South America and the second largest single institution series worldwide. A total of 34 patients underwent resection without mortality.
In line with previous studies [1, 2, 5, 8, 18], the proportion of female sex was higher (82.4%) and the most common histology type was SPN in this population. Most of the patients were ≥ 10 years old (88.2%). The most frequent symptom was abdominal pain. These were also in line with previous studies, showing that the demographic characteristics of pediatric and adolescent pancreatic tumors may be common regardless of the regions worldwide [1, 2, 19, 20].
SPN is a low grade malignant pancreas tumors which contain solid and cystic components and mainly found in female patients in the second to fourth decades of life [4]. A male-to-female ratio in incidence of SPN was 1: 9.5. The size of SPN is generally smaller in male patients than in female patients, and SPN diagnosed in male patients mainly contains solid components [19]. In pediatric and adolescent patients, SPN is generally found at the age from 10 to 20 years old [4]. Our study showed that the 3- and 5-year OS rates were 100% and 83.1% in pediatric and adolescent patients with SPN, respectively. This is in line with previous studies which showed that the OS in pediatric and adolescent patients with SPN was more than 95% and was better than OS in this patient group with other histology types of pancreas tumors [1, 5, 8, 20, 21].
Pancreatoblastoma is the second most common histology type in our study. Pancreatoblastoma was originally termed as infantile pancreatic carcinoma by Becker in 1957 [22] and is an extremely rare pancreas neoplasm which contains typical squamous corpuscles and tumor cells with acinar, glandular, or undifferentiated appearance [23]. It is predominant in male patients who are from 0 to 20 years old and has an association with Beckwith-Wiedemann syndrome [3, 24]. Serum alpha-fetoprotein level is elevated in most patients. Mylonas, et al reported 21 pediatric and adolescent patients with pancreatoblastoma. The median age of the patients 5.5 years old at the time of diagnosis [20]. In our study, of the three patients, two are alive with no evidence of recurrence after surgery and one died because of hepatic recurrence at 46 months after surgery. Bien, et al reported 20 pediatric and adolescent patients with pancreatoblastoma in a multicenter study [25]. The 5-year OS was 79.4% and the 5-year event-free survival was 58.8%. Complete surgical resection was a prognostic factor for a better event-free survival in univariate analysis.
The largest single institution retrospective study about this topic was reported in Asia [2]. The study included 104 pediatric and adolescent patients between 2007 and 2018. Other studies included approximately 30 patients mainly from North America. Our study is the largest series in the population of South America and found that female sex is dominant and SPN was the most common histology types in line with previous studies in other regions. Mylonas et al [20], reported a retrospective multicenter study using Surveillance, Epidemiology and, End Results (SEER) database, and included 114 pediatric and adolescent patients from 1973–2013. In this study, the most common histology type was NET with 40 (35%) patients followed by epithelial tumors with 29 (25%). A total of 73 (64%) patients had surgical treatment. Another study using the SEER database from 1973–2004, showing that the incidence of pancreas tumors in pediatric and adolescent patients was 0.018 per 100000 people [5].
Pancreaticoduodenectomy was the most frequent surgical procedure in our study which accounts for 19 patients (55.9%). Pancreaticoduodenectomy in pediatric and adolescent patients had been reported but the number of cases was low [26]. In children, pylorus-preserving pancreaticoduodenectomy may be considered to preserve gastric function [27, 28]. Mansfield et al reported that morbidity rate after pancreaticoduodenectomy was lower in patients \(\le\) 30 years old than in adult patients [29]. In our study, no patient experienced postoperative mortality and 15 patients (44.1%) developed postoperative complications including 5 patients (14.7%) who had major complications. Pancreatic fistula was found in 6 (31.5%) patients undergoing pancreaticoduodenectomy versus 1 (10%) patient undergoing distal pancreatectomy.
Our study is a retrospective study with a small number of patients. Nonetheless, given the rarity of pancreas tumors in pediatric and adolescent patients, our study is the second largest series worldwide and showed outcomes of pancreas tumors for this patient group in South America. Another limitation is that the functional change after pancreatectomy was not followed because most patients lived in remote areas far from our institution.
In conclusion, SPN was the most frequent cause of surgical treatment for pediatric and adolescent patients in the high-volume cancer center in Peru and was associated with favorable survival. Pancreaticoduodenectomy was safely performed in this patient group with acceptable morbidity and zero mortality.