- Email: [email protected]
Mixed mucinous adenocarcinoma and somatostatinoma of the ampulla of Vater associated with neurofibromatosis type 1
Pathology (- 2017) -(-), pp. 1e3
CORRESPONDENCE Mixed mucinous adenocarcinoma and somatostatinoma of the ampulla of Vater associated with neurofibromatosis type 1 Sir, Neurofibromatosis type 1 (NF1) is an autosomal dominant condition with a prevalence of approximately 1 in every 3000e5000 people.1,2 It is characterised by the presence of six or more cutaneous ‘cafe au lait’ macules; two or more neurofibromas, or one plexiform neurofibroma; freckling in the axillary or inguinal regions; optic glioma; two or more Lisch nodules of the iris; specific osseous lesions; or a first degree relative affected by NF1.3 Life expectancy in people with NF1 is reduced by 10e15 years primarily due to an increased risk of malignancy.1,2 In adults these malignancies include: malignant peripheral nerve sheath tumour (MPNST), gastrointestinal stromal tumour (GIST), breast cancer, duodenal neuroendocrine tumours (NET), pheochromocytoma and glioblastoma.1,2,4 In the periampullary region of the gastrointestinal tract, NETs, GISTs, adenocarcinomas, neurofibromas, schwannomas and gangliocytic paragangliomas are the most common tumours.4 A 47-year-old woman, with known NF1, underwent a pancreaticoduodenectomy (Whipple’s procedure) to remove a tumour located on the minor ampulla of Vater. The tumour was received as a frozen section specimen measuring 20 mm in maximum diameter. The main specimen contained a small amount of residual tumour associated with the minor papilla. Microscopically, both the frozen and paraffin sections of the tumour showed infiltrative neuroendocrine nests and sheets with low grade nuclear morphology (Fig. 1A,B). The tumour cells infiltrated through the muscularis propria and into the adjacent adventitia. Multiple psammomatous calcifications were present (Fig. 1C). There was a distinct 9 mm mucinous adenocarcinoma within the adventitia (Fig. 1D), adjacent to the neuroendocrine component. Mucinous metaplasia of the adjacent pancreatic duct was noted with no high grade epithelial dysplasia present. Two peripancreatic lymph nodes contained metastatic deposits of the neuroendocrine component only. The neuroendocrine component stained positively for synaptophysin, chromogranin A and somatostatin, and Ki-67 was <1%. The adenocarcinoma stained positively for CK7, CEA and CAM 5.2 but was negative for chromogranin A (Fig. 2). The patient’s post-operative course was complicated by portal venous thrombosis. A magnetic resonance imaging (MRI) cholangio-pancreatogram and abdominal computed tomography (CT) 4 years later showed no recurrent disease. Somatostatinomas, or more correctly, somatostatin expressing neuroendocrine tumours, are a rare entity with less than 200 cases reported in the gastrointestinal tract.5,6 With a predilection for the pancreas, less than 100 tumours have been reported in the duodenum.6 Compared to their pancreatic counterparts, duodenal somatostatinomas tend to be smaller when diagnosed, possibly related to their obstructive symptoms. Histologically they demonstrate characteristic psammoma bodies and tend to be purely somatostatin
producing rather than multihormonal. Patients present less often with liver or regional lymph node metastasis compared with pancreatic somatostatinomas.2,6 Duodenal somatostatinomas are rarely associated with somatostatinoma syndrome, a clinical triad of diabetes mellitus, cholelithiasis and diarrhoea.2,5 Periampullary somatostatinomas are classically related to NF1 and half of all duodenal somatostatinomas are estimated to occur in patients with NF1.2,5 Of all the periampullary tumours that occur in NF1 patients, 40% are somatostatinomas.4 Somatostatinomas occurring in patients with or without NF1 do not appear to have any significant differences in features such as presence of somatostatinoma syndrome, tumour size or the presence of psammoma bodies on histology.5 Tumours with mixed adenocarcinoma and neuroendocrine tumours are malignant lesions with considerable variation in the percentage of each component. Termed mixed adenoneuroendocrine carcinomas (MANEC) in the WHO classification (2010), these tumours will be renamed mixed neuroendocrine non-neuroendocrine neoplasm (MiNEN) in the next edition, planned for release later this year.7 Both editions require the neuroendocrine and non-neuroendocrine neoplastic components to comprise at least 30% of the lesion for the diagnosis to be made.7,8 The occurrence of periampullary MANEC/MiNENs are exceedingly rare, with only 19 cases including this current case being reported in the literature so far.9e12 This tumour was composed of mucinous adenocarcinoma and low grade (G1) neuroendocrine tumour. Overall, MANEC/MiNEN have a median age of diagnosis of 60 years (range 27e89 years), and a median tumour size of 2.0 cm (range 1.2e5.0 cm). Metastases of both the endocrine and exocrine components have been reported.9,10 Of the 19 cases, only four have reported pure somatostatin expression and none appear to be associated with a functional clinical syndrome. Interestingly, three of the four cases are associated with NF1. It has been postulated that the ampullary region in NF1 patients may be predisposed to tumour development.4 In one review, 12 cases of periampullary non-carcinoid epithelial tumour occurring in a NF1 patient were examined. The authors identified two potentially significant findings: first, the average age of the first tumour diagnosis was significantly younger than that of the general population (47 versus 68 years); second, 25% of NF1 patients subsequently developed a second non-carcinoid epithelial tumour of the periampulla.9 The presence of an endodermal-neuroectodermal complex containing multipotent cell lines has been postulated as a mechanism by which this may occur.4 This unusual case demonstrates the combination of several rare entities, which may be more than a coincidence. It is only the third reported case of a MANEC expressing somatostatinoma occurring in an NF1 patient (Table 1). The first was described by Deschamps et al in 20109 and the second by Tewari et al.12 All three patients were in their 40s when diagnosed and none appeared to have a clinical neuroendocrine syndrome. Histologically, the three tumours displayed psammoma bodies typical of duodenal somatostatinomas. Regional lymph node metastases were present in our case report and the case reported by Deschamps et al.
Print ISSN 0031-3025/Online ISSN 1465-3931 Ó 2017 Published by Elsevier B.V. on behalf of Royal College of Pathologists of Australasia.
Please cite this article in press as: Reynolds R, Marjoniemi V, Mixed mucinous adenocarcinoma and somatostatinoma of the ampulla of Vater associated with neurofibromatosis type 1, Pathology (2017), http://dx.doi.org/10.1016/j.pathol.2017.03.014
2
CORRESPONDENCE
Pathology (2017), -(-), -
The tumour demonstrated distinct areas of (A) neuroendocrine and (B) adenocarcinoma infiltrating the stroma adjacent to the ampulla of Vater. (C) The neuroendocrine component produced psammoma bodies typical of duodenal somatostatin producing neuroendocrine tumours, and (D) the adenocarcinoma produced abundant mucin.
Fig. 1
Immunohistochemistry showed neuroendocrine markers such as synaptophysin to be strongly positive in neuroendocrine tumour cells (A), and negative in mucinous adenocarcinoma cells (B). Conversely, CEA was strongly positive in the adenocarcinomatous component but negative in adjacent neuroendocrine cells (C).
Fig. 2
They reported metastasis of both adenocarcinoma and somatostatinoma components whilst only the endocrine component had metastasised in our case. Although follow up was short, both patients were alive and disease free at 3 and 4 years, respectively, despite regional lymph node metastasis.
Whilst this is the third reported somatostatin expressing MANEC/MiNEN to occur in an NF1 patient, it is only the fourth such tumour to have been reported with or without an NF1 association. Such a rare association makes it prudent to consider NF1 in any patient diagnosed with a periampullay somatostatin expressing MANEC/MiNEN. In fact, it has
Please cite this article in press as: Reynolds R, Marjoniemi V, Mixed mucinous adenocarcinoma and somatostatinoma of the ampulla of Vater associated with neurofibromatosis type 1, Pathology (2017), http://dx.doi.org/10.1016/j.pathol.2017.03.014
CORRESPONDENCE
Table 1
3
Reported cases of somatostatin producing MANEC associated with NF1 Jones et al. 198914
Deschamps et al. 20109
Tewari et al. 201412
Age Gender Clinical syndrome NF1 Overall tumour size Exocrine component
64 F No No 15 mm Goblet cell adenocarcinoma
44 M NS Yes 35 mm Well differentiated adenocarcinoma
47 F No Yes 20 mm Mucinous adenocarcinoma
Endocrine component Lymph node metastasis
Somatostatinoma No
Somatostatinoma NS
Somatostatinoma 2 nodes endocrine component
Psammoma bodies Follow up
NS Alive 3 months
49 F No Yes 50 mm High grade tubulovillous adenoma with area of invasive adenocarcinoma Somatostatinoma 3 nodes adenocarcinoma, 3 nodes endocrine component Yes Alive and disease free at 3 years
Yes NS
Yes Alive and disease free at 4 years
Current
NS, not stated.
recently been observed that rare tumours such as triple negative GIST may occur before the diagnosis of NF1 has been made13 and a high index of suspicion is warranted. In summary, we have presented an unusual case of periampullary MANEC/MiNEN, composed of a mucinous adenocarcinoma and low grade neuroendocrine tumour that expressed somatostatin and occurred in a patient with NF1. NF1 patients have an increased risk of multiple malignancies and of periampullary tumours specifically. Including this case, four periampullary MANEC/MiNEN expressing somatostatin have been reported so far. Three of these cases have occurred in association with NF1 and may represent an inherent predisposition in NF1 patients of the cancer occurring at the periampulla, and specifically for MANEC/MiNEN which produce somatostatin only. In patients not known to have NF1, consideration of this diagnosis may be prudent. These tumours present not only a diagnostic challenge, but also challenges involving patient management. Although a limited sample size, the prognosis appears promising, with two patients reported to be alive without recurrence at least 3 years following surgery. Conflicts of interest and sources of funding: The authors state that there are no conflicts of interest to disclose. Róisín Reynolds1 Veli Marjoniemi2 1
Department of Histopathology, Douglass Hanly Moir Pathology, and 2Department of Anatomical Pathology, St George Hospital, Sydney, NSW, Australia Contact Dr Róisín Reynolds. E-mail: [email protected] 1. Rasmussen SA, Friedman JM. NF1 gene and Neurofibromatosis 1. Am J Epidemiol 2000; 151: 33e40.
2. Relles D, Baek J, Witkiewicz A, et al. Periampullary and duodenal neoplasms in neurofibromatosis type 1: Two cases and an updated 20year review of the literature yielding 76 cases. J Gastrointest Surg 2010; 14: 1052e61. 3. National Institutes of Health Consensus Development. Neurofibromatosis: Conference Statement. Arch Neurol 1988; 45: 575e8. 4. Zoller M, Rembeck B, Akesson HO, et al. Life expectancy, mortality and prognostic factors in neurofibromatosis type 1: a twelve-year follow up of an epidemiological study in Goteborg, Sweden. Acta Derm Venereol 1995; 79: 136e40. 5. Nesi G, Marcucci T, Rubio CA, et al. Somatostatinoma: clinicopathological features of three cases and literature reviewed. J Gastroenterol Hepatol 2008; 23: 524e6. 6. Koc O, Duzkoylu Y, Sari YS, et al. Duodenal somatostatinoma: a case report and review of the literature. J Med Case Rep 2013; 7: 115. 7. Klöppel G. Update of WHO classification of Endocrine Pancreatic Tumors. Cited 13 Mar 2017. https://www.esp-congress.org/fileadmin/ user_upload/Congress_2016/IAP_ESP_Presentations/Mon/0830-1200/ SY-02/SY-02-004-Klöppel-Update%20of%20WHO%20classification% 20of%20endocrine%20pancreatic%20tumours.pdf. 8. Rindi G, Arnold R, Bosman FT, et al. Nomenclature and classification of neuroendocrine neoplasms of the digestive system. In: Bosman FT, Carneiro F, Hruban RH, Theise ND, editors. WHO Classification of Tumours of the Digestive System. 4th ed. Lyon: IARC Press, 2010; 13e 4. 9. Deschamps L, Dokmak S, Guedj N, et al. Mixed endocrine somatostatinomas of the Ampulla of Vater associated with a Neurofibromatosis type 1: A case report and review of the literature. J Pancreas 2010; 11: 64e8. 10. Vilardell F, Velasco A, Cuevas D, et al. Composite papillary intestinaltype adenocarcinomas/poorly differentiated neuroendocrine carcinomas of the ampulla of Vater. J Clin Pathol 2011; 64: 174e7. 11. Huang Z, Wei-Dong X, Li Y, et al. Mixed adenoneuroendocrine carcinoma of the ampulla: Two case reports. World J Gastroenterol 2015; 21: 2254e9. 12. Tewari N, Rollins, Gandhi N, et al. Mixed periampullary adenocarcinoma and somatostatinoma with small bowel gastrointestinal stromal tumour in neurofibromatosis Type 1. JOP 2014; 15: 600e3. 13. Gasparotto D, Rossi S, Polano M, et al. Quadruple-negative GIST is a sentinel for unrecognized neurofibromatosis type 1 syndrome. Clin Cancer Res 2017; 23: 273e8. 14. Jones MA, Griffith LM, West AB. Adenocarcinoid tumor of the periampullary region: a novel duodenal neoplasm presenting as biliary tract obstruction. Hum Pathol 1989; 20: 198e200.
DOI: http://dx.doi.org/10.1016/j.pathol.2017.03.014
Please cite this article in press as: Reynolds R, Marjoniemi V, Mixed mucinous adenocarcinoma and somatostatinoma of the ampulla of Vater associated with neurofibromatosis type 1, Pathology (2017), http://dx.doi.org/10.1016/j.pathol.2017.03.014
CORRESPONDENCE Mixed mucinous adenocarcinoma and somatostatinoma of the ampulla of Vater associated with neurofibromatosis type 1 Sir, Neurofibromatosis type 1 (NF1) is an autosomal dominant condition with a prevalence of approximately 1 in every 3000e5000 people.1,2 It is characterised by the presence of six or more cutaneous ‘cafe au lait’ macules; two or more neurofibromas, or one plexiform neurofibroma; freckling in the axillary or inguinal regions; optic glioma; two or more Lisch nodules of the iris; specific osseous lesions; or a first degree relative affected by NF1.3 Life expectancy in people with NF1 is reduced by 10e15 years primarily due to an increased risk of malignancy.1,2 In adults these malignancies include: malignant peripheral nerve sheath tumour (MPNST), gastrointestinal stromal tumour (GIST), breast cancer, duodenal neuroendocrine tumours (NET), pheochromocytoma and glioblastoma.1,2,4 In the periampullary region of the gastrointestinal tract, NETs, GISTs, adenocarcinomas, neurofibromas, schwannomas and gangliocytic paragangliomas are the most common tumours.4 A 47-year-old woman, with known NF1, underwent a pancreaticoduodenectomy (Whipple’s procedure) to remove a tumour located on the minor ampulla of Vater. The tumour was received as a frozen section specimen measuring 20 mm in maximum diameter. The main specimen contained a small amount of residual tumour associated with the minor papilla. Microscopically, both the frozen and paraffin sections of the tumour showed infiltrative neuroendocrine nests and sheets with low grade nuclear morphology (Fig. 1A,B). The tumour cells infiltrated through the muscularis propria and into the adjacent adventitia. Multiple psammomatous calcifications were present (Fig. 1C). There was a distinct 9 mm mucinous adenocarcinoma within the adventitia (Fig. 1D), adjacent to the neuroendocrine component. Mucinous metaplasia of the adjacent pancreatic duct was noted with no high grade epithelial dysplasia present. Two peripancreatic lymph nodes contained metastatic deposits of the neuroendocrine component only. The neuroendocrine component stained positively for synaptophysin, chromogranin A and somatostatin, and Ki-67 was <1%. The adenocarcinoma stained positively for CK7, CEA and CAM 5.2 but was negative for chromogranin A (Fig. 2). The patient’s post-operative course was complicated by portal venous thrombosis. A magnetic resonance imaging (MRI) cholangio-pancreatogram and abdominal computed tomography (CT) 4 years later showed no recurrent disease. Somatostatinomas, or more correctly, somatostatin expressing neuroendocrine tumours, are a rare entity with less than 200 cases reported in the gastrointestinal tract.5,6 With a predilection for the pancreas, less than 100 tumours have been reported in the duodenum.6 Compared to their pancreatic counterparts, duodenal somatostatinomas tend to be smaller when diagnosed, possibly related to their obstructive symptoms. Histologically they demonstrate characteristic psammoma bodies and tend to be purely somatostatin
producing rather than multihormonal. Patients present less often with liver or regional lymph node metastasis compared with pancreatic somatostatinomas.2,6 Duodenal somatostatinomas are rarely associated with somatostatinoma syndrome, a clinical triad of diabetes mellitus, cholelithiasis and diarrhoea.2,5 Periampullary somatostatinomas are classically related to NF1 and half of all duodenal somatostatinomas are estimated to occur in patients with NF1.2,5 Of all the periampullary tumours that occur in NF1 patients, 40% are somatostatinomas.4 Somatostatinomas occurring in patients with or without NF1 do not appear to have any significant differences in features such as presence of somatostatinoma syndrome, tumour size or the presence of psammoma bodies on histology.5 Tumours with mixed adenocarcinoma and neuroendocrine tumours are malignant lesions with considerable variation in the percentage of each component. Termed mixed adenoneuroendocrine carcinomas (MANEC) in the WHO classification (2010), these tumours will be renamed mixed neuroendocrine non-neuroendocrine neoplasm (MiNEN) in the next edition, planned for release later this year.7 Both editions require the neuroendocrine and non-neuroendocrine neoplastic components to comprise at least 30% of the lesion for the diagnosis to be made.7,8 The occurrence of periampullary MANEC/MiNENs are exceedingly rare, with only 19 cases including this current case being reported in the literature so far.9e12 This tumour was composed of mucinous adenocarcinoma and low grade (G1) neuroendocrine tumour. Overall, MANEC/MiNEN have a median age of diagnosis of 60 years (range 27e89 years), and a median tumour size of 2.0 cm (range 1.2e5.0 cm). Metastases of both the endocrine and exocrine components have been reported.9,10 Of the 19 cases, only four have reported pure somatostatin expression and none appear to be associated with a functional clinical syndrome. Interestingly, three of the four cases are associated with NF1. It has been postulated that the ampullary region in NF1 patients may be predisposed to tumour development.4 In one review, 12 cases of periampullary non-carcinoid epithelial tumour occurring in a NF1 patient were examined. The authors identified two potentially significant findings: first, the average age of the first tumour diagnosis was significantly younger than that of the general population (47 versus 68 years); second, 25% of NF1 patients subsequently developed a second non-carcinoid epithelial tumour of the periampulla.9 The presence of an endodermal-neuroectodermal complex containing multipotent cell lines has been postulated as a mechanism by which this may occur.4 This unusual case demonstrates the combination of several rare entities, which may be more than a coincidence. It is only the third reported case of a MANEC expressing somatostatinoma occurring in an NF1 patient (Table 1). The first was described by Deschamps et al in 20109 and the second by Tewari et al.12 All three patients were in their 40s when diagnosed and none appeared to have a clinical neuroendocrine syndrome. Histologically, the three tumours displayed psammoma bodies typical of duodenal somatostatinomas. Regional lymph node metastases were present in our case report and the case reported by Deschamps et al.
Print ISSN 0031-3025/Online ISSN 1465-3931 Ó 2017 Published by Elsevier B.V. on behalf of Royal College of Pathologists of Australasia.
Please cite this article in press as: Reynolds R, Marjoniemi V, Mixed mucinous adenocarcinoma and somatostatinoma of the ampulla of Vater associated with neurofibromatosis type 1, Pathology (2017), http://dx.doi.org/10.1016/j.pathol.2017.03.014
2
CORRESPONDENCE
Pathology (2017), -(-), -
The tumour demonstrated distinct areas of (A) neuroendocrine and (B) adenocarcinoma infiltrating the stroma adjacent to the ampulla of Vater. (C) The neuroendocrine component produced psammoma bodies typical of duodenal somatostatin producing neuroendocrine tumours, and (D) the adenocarcinoma produced abundant mucin.
Fig. 1
Immunohistochemistry showed neuroendocrine markers such as synaptophysin to be strongly positive in neuroendocrine tumour cells (A), and negative in mucinous adenocarcinoma cells (B). Conversely, CEA was strongly positive in the adenocarcinomatous component but negative in adjacent neuroendocrine cells (C).
Fig. 2
They reported metastasis of both adenocarcinoma and somatostatinoma components whilst only the endocrine component had metastasised in our case. Although follow up was short, both patients were alive and disease free at 3 and 4 years, respectively, despite regional lymph node metastasis.
Whilst this is the third reported somatostatin expressing MANEC/MiNEN to occur in an NF1 patient, it is only the fourth such tumour to have been reported with or without an NF1 association. Such a rare association makes it prudent to consider NF1 in any patient diagnosed with a periampullay somatostatin expressing MANEC/MiNEN. In fact, it has
Please cite this article in press as: Reynolds R, Marjoniemi V, Mixed mucinous adenocarcinoma and somatostatinoma of the ampulla of Vater associated with neurofibromatosis type 1, Pathology (2017), http://dx.doi.org/10.1016/j.pathol.2017.03.014
CORRESPONDENCE
Table 1
3
Reported cases of somatostatin producing MANEC associated with NF1 Jones et al. 198914
Deschamps et al. 20109
Tewari et al. 201412
Age Gender Clinical syndrome NF1 Overall tumour size Exocrine component
64 F No No 15 mm Goblet cell adenocarcinoma
44 M NS Yes 35 mm Well differentiated adenocarcinoma
47 F No Yes 20 mm Mucinous adenocarcinoma
Endocrine component Lymph node metastasis
Somatostatinoma No
Somatostatinoma NS
Somatostatinoma 2 nodes endocrine component
Psammoma bodies Follow up
NS Alive 3 months
49 F No Yes 50 mm High grade tubulovillous adenoma with area of invasive adenocarcinoma Somatostatinoma 3 nodes adenocarcinoma, 3 nodes endocrine component Yes Alive and disease free at 3 years
Yes NS
Yes Alive and disease free at 4 years
Current
NS, not stated.
recently been observed that rare tumours such as triple negative GIST may occur before the diagnosis of NF1 has been made13 and a high index of suspicion is warranted. In summary, we have presented an unusual case of periampullary MANEC/MiNEN, composed of a mucinous adenocarcinoma and low grade neuroendocrine tumour that expressed somatostatin and occurred in a patient with NF1. NF1 patients have an increased risk of multiple malignancies and of periampullary tumours specifically. Including this case, four periampullary MANEC/MiNEN expressing somatostatin have been reported so far. Three of these cases have occurred in association with NF1 and may represent an inherent predisposition in NF1 patients of the cancer occurring at the periampulla, and specifically for MANEC/MiNEN which produce somatostatin only. In patients not known to have NF1, consideration of this diagnosis may be prudent. These tumours present not only a diagnostic challenge, but also challenges involving patient management. Although a limited sample size, the prognosis appears promising, with two patients reported to be alive without recurrence at least 3 years following surgery. Conflicts of interest and sources of funding: The authors state that there are no conflicts of interest to disclose. Róisín Reynolds1 Veli Marjoniemi2 1
Department of Histopathology, Douglass Hanly Moir Pathology, and 2Department of Anatomical Pathology, St George Hospital, Sydney, NSW, Australia Contact Dr Róisín Reynolds. E-mail: [email protected] 1. Rasmussen SA, Friedman JM. NF1 gene and Neurofibromatosis 1. Am J Epidemiol 2000; 151: 33e40.
2. Relles D, Baek J, Witkiewicz A, et al. Periampullary and duodenal neoplasms in neurofibromatosis type 1: Two cases and an updated 20year review of the literature yielding 76 cases. J Gastrointest Surg 2010; 14: 1052e61. 3. National Institutes of Health Consensus Development. Neurofibromatosis: Conference Statement. Arch Neurol 1988; 45: 575e8. 4. Zoller M, Rembeck B, Akesson HO, et al. Life expectancy, mortality and prognostic factors in neurofibromatosis type 1: a twelve-year follow up of an epidemiological study in Goteborg, Sweden. Acta Derm Venereol 1995; 79: 136e40. 5. Nesi G, Marcucci T, Rubio CA, et al. Somatostatinoma: clinicopathological features of three cases and literature reviewed. J Gastroenterol Hepatol 2008; 23: 524e6. 6. Koc O, Duzkoylu Y, Sari YS, et al. Duodenal somatostatinoma: a case report and review of the literature. J Med Case Rep 2013; 7: 115. 7. Klöppel G. Update of WHO classification of Endocrine Pancreatic Tumors. Cited 13 Mar 2017. https://www.esp-congress.org/fileadmin/ user_upload/Congress_2016/IAP_ESP_Presentations/Mon/0830-1200/ SY-02/SY-02-004-Klöppel-Update%20of%20WHO%20classification% 20of%20endocrine%20pancreatic%20tumours.pdf. 8. Rindi G, Arnold R, Bosman FT, et al. Nomenclature and classification of neuroendocrine neoplasms of the digestive system. In: Bosman FT, Carneiro F, Hruban RH, Theise ND, editors. WHO Classification of Tumours of the Digestive System. 4th ed. Lyon: IARC Press, 2010; 13e 4. 9. Deschamps L, Dokmak S, Guedj N, et al. Mixed endocrine somatostatinomas of the Ampulla of Vater associated with a Neurofibromatosis type 1: A case report and review of the literature. J Pancreas 2010; 11: 64e8. 10. Vilardell F, Velasco A, Cuevas D, et al. Composite papillary intestinaltype adenocarcinomas/poorly differentiated neuroendocrine carcinomas of the ampulla of Vater. J Clin Pathol 2011; 64: 174e7. 11. Huang Z, Wei-Dong X, Li Y, et al. Mixed adenoneuroendocrine carcinoma of the ampulla: Two case reports. World J Gastroenterol 2015; 21: 2254e9. 12. Tewari N, Rollins, Gandhi N, et al. Mixed periampullary adenocarcinoma and somatostatinoma with small bowel gastrointestinal stromal tumour in neurofibromatosis Type 1. JOP 2014; 15: 600e3. 13. Gasparotto D, Rossi S, Polano M, et al. Quadruple-negative GIST is a sentinel for unrecognized neurofibromatosis type 1 syndrome. Clin Cancer Res 2017; 23: 273e8. 14. Jones MA, Griffith LM, West AB. Adenocarcinoid tumor of the periampullary region: a novel duodenal neoplasm presenting as biliary tract obstruction. Hum Pathol 1989; 20: 198e200.
DOI: http://dx.doi.org/10.1016/j.pathol.2017.03.014
Please cite this article in press as: Reynolds R, Marjoniemi V, Mixed mucinous adenocarcinoma and somatostatinoma of the ampulla of Vater associated with neurofibromatosis type 1, Pathology (2017), http://dx.doi.org/10.1016/j.pathol.2017.03.014