2022, Volume 38, Number 1, Page(s) 046-053
Mesenchymal Tumors Involving the Pancreas: A Clinicopathologic Analysis and Review of the Literature
Gokce ASKAN, Olca BASTURK
Department of Pathology, Memorial Sloan Kettering Cancer Center, NEW YORK, USA
Keywords: Pancreas, Mesenchymal tumors, Benign, Malignant
Most pancreatic tumors are epithelial, and, among these, more than 90% are of ductal origin. However, a variety of mesenchymal
tumors may involve the pancreas and may manifest different clinicopathological characteristics. The literature on mesenchymal tumors in the
pancreas is largely limited to individual case reports or analyses of small series, predominantly focusing on radiologic features.
Material and Method: Authorsí institutional and consultation databases were reviewed to identify the mesenchymal tumors involving the
Results: Forty cases were identified; twenty-five (63%) tumors were benign/borderline, and the remaining fifteen (37%) were malignant. Of
the benign/borderline tumors; 9 were solitary fibrous tumors, 6 gastrointestinal stromal tumors (GISTs), 4 schwannomas, 2 desmoid type
fibromatosis, 1 lymphangioma, 1 ganglioneuroma, 1 inflammatory myofibroblastic tumor, and 1 low grade mesenchymal neoplasm. Malignant
tumors included 6 cases of leiomyosarcomas, 4 liposarcomas, 2 rhabdomyosarcomas, 1 epithelioid angiosarcoma, 1 malignant peripheral nerve
sheet tumor, and 1 undifferentiated pleomorphic sarcoma. Four cases (multicystic schwannoma, desmoid fibromatosis, lymphangioma and
inflammatory myofibroblastic tumor) were preoperatively misdiagnosed as a primary epithelial tumor of the pancreas.
Conclusion: Mesenchymal tumors rarely involve the pancreas. They are usually benign/borderline neoplasms but may be diagnostically
challenging, especially clinically/radiologically, as they may form cystic and/or large lesions in the pancreas. Mesenchymal tumors should be
considered in both the clinical/radiological and pathological differential diagnosis of pancreatic lesions.
The majority of the tumors involving the pancreas
are of epithelial origin, and of these, pancreatic ductal
adenocarcinomas (PDACs) are the most common primary
. However, mesenchymal tumors could involve
the pancreas, too. Although imaging studies might be
helpful to distinguish, some mesenchymal tumors might
mimic epithelial ones very well 2
. Moreover, radiologic
findings could be misleading when the tumors present as a
cystic and/or large lesion, as it gets difficult to identify the
site of origin 1,3-5
Primary mesenchymal tumors of the pancreas comprise
only 1-2% of all pancreatic neoplasms 1, and the literature
on mesenchymal tumors involving the pancreas is largely
limited to case reports or analyses of small series 3,6-15.
Here, we present a large series of mesenchymal tumors
involving the pancreas, discuss their clinicopathologic
features and differential diagnoses, and compare our
findings with the previous experience reported in the
Pathology reports of autopsies and surgical pancreatic
specimens from the authorsí institutional and consultation
databases (1997-2020) have been reviewed to identify the
mesenchymal tumors involving the pancreas.
Available gross photographs and descriptions as well
as all histologic sections and immunohistochemical
staining slides were re-evaluated to confirm the diagnosis.
Available medical records, including imaging study
reports, were reviewed to obtain clinical data including
age, sex, presenting symptoms, treatment, and outcome.
For the consultation cases, contributing physicians were
contacted. Tumors that are metastatic to the pancreas
from a remote site as well as tumors that were confined
to the peripancreatic soft tissue or lymph nodes, without
pancreatic involvement, were excluded.
Mean, median and ranges were used to describe quantitative
variables. The Mann-Whitney U test or Fisher`s exact test was used to evaluate the differences in clinicopathologic
features between benign/borderline and malignant
tumors of the pancreas. P-values of <0.05 were considered
A total of forty cases were identified. Clinicopathologic
features of these cases were summarized in Table I
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|Table I: Clinicopathologic features of benign/borderline and malignant mesencyhmal tumors involving the pancreas.
The mean age of the patients was 55 years for the entire
cohort, younger than that of PDAC (mean age: 64 years).
Twenty (50%) patients were female and twenty (50%) were
male. Mean tumor size was 6 cm (range, 0.5-20 cm).
Twenty-five (63%) cases were classified as benign/
borderline tumors, including nine solitary fibrous tumors
(detailed analysis of these tumors is subject to another
study) (16), six gastrointestinal stromal tumors (GISTs),
four schwannomas (two (multi)cystic, two solid), two
desmoid type fibromatosis, one lymphangioma, one
ganglioneuroma, one inflammatory myofibroblastic
tumor, and one low grade mesenchymal neoplasm. The
remaining fifteen (37%) cases were malignant tumors,
including six cases of leiomyosarcomas, four liposarcomas
(three dedifferentiated liposarcomas, one pleomorphic
liposarcoma), two rhabdomyosarcomas (one alveolar, one
embryonal), one epithelioid angiosarcoma, one malignant
peripheral nerve sheet tumor, and one undifferentiated
When benign/borderline and malignant mesenchymal
tumors were compared, no gender predominance was
identified in either group, and there was no statistically
significant difference in the mean age of the patients (55 years vs. 56 years, respectively; p=0.68). The mean tumor
size of benign/borderline mesenchymal tumors was smaller
than that of malignant tumors (5 cm vs. 11 cm, respectively;
Detailed clinical information was available for twenty-five
(63%) patients. The most common presenting symptoms
were abdominal pain, loss of appetite, and weight loss.
Four (16%) cases (solitary fibrous tumor, GIST, desmoid
type fibromatosis, and dedifferentiated liposarcoma)
were diagnosed incidentally during work-up for other
intraabdominal pathologies. Four tumors (multicystic
schwannoma, desmoid type fibromatosis, lymphangioma,
and inflammatory myofibroblastic tumor) were
clinically misdiagnosed (as mucinous cystic neoplasm,
serous cystadenoma, lymphoepithelial cyst, and PDAC,
Two patients, one with GIST and another one with
embryonal rhabdomyosarcoma, received neoadjuvant
chemotherapy; one patient with leiomyosarcoma received
neoadjuvant radiotherapy. Twenty patients underwent a
pylorus-preserving pancreaticoduodenectomy: nine had a
distal pancreatectomy, and ten had a local excision. One
patient with leiomyosarcoma underwent autopsy.
Of the known thirty-six cases, twenty-one (58%) tumors
were involving the head of the pancreas (Figure 1).
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|Figure 1: A) Desmoid type fibromatosis, characterized by a solid, ill-defined mass with tan-white cut surface, involving tail of the
pancreas. B) Leiomyosarcoma involving the pancreas, peripancreatic adipose tissue, and the gastric wall. The mass is vaguely nodular
and reveals hemorrhagic foci. C) Dedifferentiated liposarcoma involving head of the pancreas. The tumor is relatively well-circumscribed
and has a fleshy cut surface.
Pathologic features of the majority of the tumors were
identical to those of mesenchymal tumors arising from soft
tissue or other organs (Figures 1-8). Solitary fibrous tumors
(Figure 2) characteristically revealed variable labeling with CD34 and STAT6 immunohistochemical stains. GISTs
(Figure 3) showed positivity for CD117, DOG1, SMA, and
CD34. Moreover, two GISTs revealed KIT and another
one revealed PDGFRA mutations. Schwannomas (Figure
4) demonstrated S100 protein expression. Fibromatoses
were confirmed by nuclear beta-catenin staining.
Lymphangioma labeled with CD31. Schwann cells and
ganglion cells of ganglioneuroma (Figure 5) were positive
for S100 and neurofilament proteins, and synaptophysin.
The inflammatory myofibroblastic tumor revealed ALK
expression. Leiomyosarcomas (Figure 6) showed diffuse
and strong immunoreactivity for SMA and desmin.
Liposarcomas (Figure 7) were positive for CDK4 and
MDM2 immunohistochemical stains, and the only case
tested was found to harbor CDK4 and MDM2 mutations.
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|Figure 2: Solitary fibrous tumor composed of alternating zones
of hypo and hypercellular areas and variably collagenous stroma
(x100). Ovoid to fusiform spindled tumor cells, with indistinct
cell borders and bland nuclei, are haphazardly distributed around
dilated vascular structures (inset, x200).
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|Figure 3: Gastrointestinal stromal tumor composed of spindle
cells, with oval shaped nuclei and lightly eosinophilic cytoplasm,
arranged in fascicles (x100).
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|Figure 4: Schwannoma composed of interlacing bundles of
spindle cells and collagen. The tumor cells have ill-defined, dense
eosinophilic cytoplasm and ovoid to spindled nuclei (x200).
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|Figure 5: Ganglioneuroma composed of an admixture of schwann
cells, with eosinophilic cytoplasm and wavy nuclei, arranged in
a fascicular or whorled pattern (x100) and mature ganglion cells
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|Figure 6: Leiomyosarcoma composed of palisading of tumor
cells with prominent pleomorphism (x100). Tumor cells have
oval to cigar-shaped, blunt-ended nuclei and light eosinophilic
cytoplasm (inset, x200).
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|Figure 7: Pleomorphic liposarcoma involving pancreatic
parenchyma (x100). Tumor cells have hyperchromatic bizarre
nuclei (some in floret-like multinucleated giant cell forms) and
light eosinophilic cytoplasm (inset, x200).
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|Figure 8: Malignant peripheral nerve sheet tumor composed of
predominantly monomorphic spindle cells with scant to moderate
eosinophilic, ill-defined cytoplasm arranged in fascicular and
whorling pattern. Our case revealed heterologous chondromatous
Rhabdomyosarcomas expressed vimentin, desmin, myoD1,
and myogenin. Epithelioid angiosarcoma was diffusely
and strongly positive for vascular markers, CD31, Factor
VIII, and Fli-1, as well as for keratin. Of note, this case also
had a minute solid pseudopapillary neoplasm (SPN) of
the pancreas; however, the tumors were morphologically
distinct, and the immunohistochemical staining of the SPN
component was quite characteristic, with vimentin, alpha
1 antitrypsin, CD10, and nuclear beta-catenin expression.
Moreover, the SPN component was negative for vascular
markers and keratin.
Another case revealed a predominantly monomorphic
spindle cell neoplasm arranged in intersecting long
fascicles, associated with areas of necrosis and high mitotic activity. A focus of cartilaginous divergent differentiation
was also identified (Figure 8). By immunohistochemistry,
the tumor cells were positive for S100 protein, while
negative for desmin, myogenin, SOX10, MDM2, and
CDK4. KIT and PDGFRA mutation analyses were also
negative. FISH studies, performed to rule out the possibility
of gastrointestinal clear cell sarcoma and a myoepithelial
tumor, showed no rearrangement of the EWSR1, FUS,
ATF1, and CREB1 genes. Based on the morphology and
immunoprofile, the tumor was classified as a high grade
malignant peripheral nerve sheath tumor with divergent
There were two unusual cases: one multinodular tumor
was composed of monomorphic cells with ovoid to
round nuclei, arranged in a vaguely nested pattern
(Figure 9). Despite extensive work-up the tumor could
not be further characterized and classified as a low-grade
mesenchymal neoplasm. (Immunohistochemical stains
showed that the tumor cells were positive for desmin and
TFE3, while negative for pancytokeratin, CAM5.2, EMA,
chromogranin, synaptophysin, NSE, CD45, SMA, HHF35,
myogenin, CD117, DOG1, MUC4, S100, SOX10, HMB45,
Melan-A, CD31, ERG, TLE1, STAT6, and Cathepsin-K).
Beta-catenin revealed membranous staining. The Ki67
proliferative index was less than 5%. FISH studies
showed no rearrangement of the EWSR1, FUS, GLI1,
TFE3, NOTCH2, NCOA2, and PHF genes. Targeted next
generation sequencing involving all targeted (≥ 400) genes
did not reveal any somatic mutations or amplifications/
homozygous deletions in any known oncogenes or tumor
suppressor genes. The Archer FusionPlex assay did not
detect any recurrent likely pathogenic gene fusions).
Another tumor was composed of pleomorphic spindle
cells with malignant features including necrosis, high
mitotic counts, and nuclear atypia. The tumor did not
reveal any specific differentiation (immunohistochemical
stains showed that the tumor cells were negative for
pancytokeratin, SMA, desmin, CD117, DOG1, CD34S100,
Melan-A, and HMB45). FISH analysis for the detection
of MDM2 gene amplifications was also performed to rule
out the possibility of dedifferentiated liposarcoma, and the
result was negative. Based on these, the tumor was classified
as an undifferentiated pleomorphic sarcoma.
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|Figure 9: Low grade mesenchymal neoplasm involving pancreatic
parenchyma and duodenal wall (x100). The tumor is composed
of monomorphic cells with ovoid to round nuclei, arranged in a
vaguely nested pattern. Increased vascularity is also noted (inset,
x200). This tumor could not be further characterized despite
Moreover, two benign (desmoid type fibromatosis and
ganglioneuroma) and four malignant (three dedifferentiated
liposarcomas and one embryonal rhabdomyosarcoma)
tumors had positive surgical margin(s). Five tumors (two
rhabdomyosarcomas, two GISTs, and one solitary fibrous
tumor) were found to have metastatic lymph node(s). The tumor diameter for GISTs with metastatic lymph node was
4 cm and 5 cm, and the mitotic count was 1 mitosis per 50
high power fields and 3 mitoses per 50 high power fields,
respectively. Of note, the case with the largest tumor (16
cm) had no lymph node metastasis.
Moreover, one GIST and the epithelioid angiosarcoma
had concurrent tumors in other organs: an ampullary
adenocarcinoma and an appendiceal neuroendocrine
Clinical follow-up was available for twenty-eight (70%)
cases. The mean follow-up was 37 months for the entire
cohort (range, 3-140 months).
Follow-up information was available for twenty patients
with a benign/borderline mesenchymal tumor. Eighteen
(90%) patients are alive with no evidence of disease, with
a mean follow-up 39 months. One patient with a GIST
had distant metastasis after 68 months and is alive. The
remaining one died of other causes.
Follow-up information was available for eight patients
with a malignant mesenchymal tumor. Four (50%) patients
are alive with no evidence of disease, with a mean followup
28 months. Two (25%) patients with dedifferentiated
liposarcoma had a local recurrence after 6 and 48 months,
respectively and are alive. Two (25%) patients, one with
a leiomyosarcoma and one with a malignant peripheral
nerve sheet tumor, had distant metastasis after 4 months
and both patients died of disease after 8 months.
Mesenchymal tumors rarely involve the pancreas and most
of them are believed to be secondary lesions 1,17
experience is mainly based on individual case reports,
analyses of small series of cases, or opinions presented in
textbooks, predominantly focusing on radiologic features
. To the best of our knowledge, our study is
the largest study documenting clinicopathologic features of
mesenchymal tumors involving the pancreas.
In the literature, the most commonly reported primary
benign/borderline mesenchymal tumors were schwannoma
followed by inflammatory myofibroblastic tumor, whereas
the most commonly reported malignant ones were
leiomyosarcoma and undifferentiated sarcomas 3,6-11,19-23. In our series, the most common benign/borderline
mesenchymal tumors involving the pancreas were solitary
fibrous tumor (n=9), followed by schwannoma (n=4), and
the most common malignant ones were leiomyosarcoma
(n=6), followed by liposarcoma (n=4).
Mesenchymal tumors can mimic epithelial tumors of
the pancreas and the patientsí demographics, clinical
symptoms, or tumor location are not helpful to distinguish
these two tumor categories. In our series, the mean age
was 55 years, younger than that of PDAC, but the most
common presenting symptom was abdominal pain in both
groups. Moreover, radiologically, mesenchymal tumors
may closely mimic pancreatic epithelial tumors, making
the preoperative diagnosis difficult 3-5,17,24. Therefore,
surgical resection and histologic examination is necessary.
For example, desmoid type fibromatosis is a benign but
locally agressive tumor, mostly located in the pancreatic
tail 25-28. Radiologically, it can mimic PDAC due to
obstruction of the pancreatic duct 28-30. Interestingly,
one of the desmoid type fibromatosis cases in our series
was preoperatively diagnosed as microcystic serous
cystadenoma. Fortunately, these tumors are histologically
When they are cystic, mesenchymal tumors may mimic
pancreatic epithelial tumors not only radiologically but
also histologically. Schwannomas and lymphangiomas
are the most common mesenchymal tumors that can
present as cystic lesions and mimic the cystic epithelial
tumors such as intraductal papillary mucinous neoplasm,
mucinous cystic neoplasm, serous cystadenoma, and cystic
neuroendocrine tumor 15,31. One of our schwannoma
cases presented as a multicystic lesion and not only
clinically but also histologically mimicked mucinous cystic
neoplasm (spindle cells mimicked ovarian-type stroma).
Immunohistochemical stains were helpful (the tumor cells
were positive for S100, while negative for SMA, desmin,
ER, and PR) to exclude the possibility of mucinous cystic
neoplasm. The lymphangioma case that presented as a
cystic lesion in our series was also clinically misdiagnosed
as a lymphoepithelial cyst 31-33. Morphology and
immunohistochemical stains were helpful to confirm
the lymphatic nature of the tumor (the tumor cells were
positive for CD31, CD34, and factor VIII, while negative
Malignant mesenchymal tumors could be also very
challenging because the possibility of sarcomatoid
carcinoma must be excluded by extensive, if not total,
sampling, and careful microscopic examination is required
to search for epithelial components, which might be very
focal. Immunohistochemical stains and molecular studies
are also frequently necessary, especially if the malignant
tumors in the differential diagnosis have a specific
immunoprofile or molecular features. For example,
presence of MDM2 protein expression and/or MDM2 gene amplifications confirm the diagnosis of dedifferentiated
liposarcoma 2,3,34-36. In our series, there were three
liposarcomas; two were dedifferentiated and one was of
the pleomorphic subtype. Patients with dedifferentiated
liposarcoma had positive surgical margin(s) and developed
a local recurrence, after 10 months and 53 months,
Interestingly, in our series, there were also two cases of
rhabdomyosarcoma, one embryonal and one alveolar
subtype, which were consultation cases. The ages of the
patients were 2 and 19 years, respectively and both tumors
were located in the pancreatic head. Rhabdomyosarcomas
are malignant tumors arising from the embryonic
mesenchyme with the potential to differentiate into
skeletal muscle. They are most commonly seen in infants
and children. The pancreas is a very unusual site for this
tumor, and only a few cases have been described in the
literature 37. This rare entity should be kept in mind
for children and young adults with an abdominal mass to
expedite the diagnosis and start the additional treatment
as they are chemosensitive tumors and surgical treatment
is followed by chemoradiation therapy 38,39. Follow-up
information was available for only one of our patients with
rhabdomyosarcoma, who received chemoradiation therapy
and the patient has no evidence of disease after 4 months.
In conclusion, mesenchymal tumors rarely involve
the pancreas. They could present as a solid or a cystic
mass and preoperative diagnosis is usually challenging
as their radiologic findings may not be specific. These
tumors may mimic the pancreatic epithelial neoplasms
even histologically. In our series, four patients, all with a
benign/ borderline mesenchymal tumor, were clinically
misdiagnosed. Histopathological examination and
extensive ancillary studies are necessary for a definite
CONFLICT of INTEREST
The authors declare no conflict of interest.
Concept: OB, Design: OB, GA, Data collection or
processing: OB, Analysis or Interpretation: OB, GA,
Literature search: GA, Writing: OB, GA, Approval: OB.
1) Lazar AJ, Hornick JL. WHO Classification of Tumours of the
Digestive System. 5th ed. Fukayama M, Goldblum JR, Miettinen
M, Lazar AJ, editors. Lyon: WHO; 2019. 433-97.
2) Askan G, Basturk O. Expression of calretinin, marker of
mesothelial differentiation, in pancreatic ductal adenocarcinoma:
A potential diagnostic pitfall. Turk Patoloji Derg. 2021;37:115-20.
3) Kim JY, Song JS, Park H, Byun JH, Song KB, Kim KP, Kim SC,
Hong SM. Primary mesenchymal tumors of the pancreas: Singlecenter
experience over 16 years. Pancreas. 2014;43:959-68.
4) Manning MA, Srivastava A, Paal EE, Gould CF, Mortele KJ.
Nonepithelial neoplasms of the pancreas: Radiologic-pathologic
correlation, part 1--benign tumors: From the radiologic
pathology archives. Radiographics. 2016;36:123-41.
5) Manning MA, Paal EE, Srivastava A, Mortele KJ. Nonepithelial
neoplasms of the pancreas, part 2: Malignant tumors and tumors
of uncertain malignant potential from the radiologic pathology
archives. Radiographics. 2018;38:1047-72.
6) Devi J, Sathyalakshmi R, Chandramouleeswari K, Devi NR.
Pancreatic schwannoma - a rare case report. J Clin Diagn Res.
7) Ciledag N, Arda K, Aksoy M. Pancreatic schwannoma: A case
report and review of the literature. Oncol Lett. 2014;8:2741-43.
8) Ohbatake Y, Makino I, Kitagawa H, Nakanuma S, Hayashi H,
Nakagawara H, Miyashita T, Tajima H, Takamura H, Ninomiya
I, Fushida S, Fujimura, Ohta T. A case of pancreatic schwannoma
- The features in imaging studies compared with its pathological
findings: Report of a case. Clin J Gastroenterol. 2014;7:265-70.
9) Moriya T, Kimura W, Hirai I, Takeshita A, Tezuka K, Watanabe
T, Mizutani M, Fuse A. Pancreatic schwannoma: Case report
and an updated 30-year review of the literature yielding 47 cases.
World J Gastroenterol. 2012;18:1538-44.
10) Lacoste L, Galant C, Gigot JF, Lacoste B, Annet L. Inflammatory
myofibroblastic tumor of the pancreatic head. JBR-BTR.
11) Kocakoc E, Havan N, Bilgin M, Atay M. Primary pancreatic
leiomyosarcoma. Iran J Radiol. 2014;11:e4880.
12) Akbulut S, Yavuz R, Otan E, Hatipoglu S. Pancreatic
extragastrointestinal stromal tumor: A case report and
comprehensive literature review. World J Gastrointest Surg.
13) Xu B, Zhu LH, Wu JG, Wang XF, Matro E, Ni JJ. Pancreatic solid
cystic desmoid tumor: Case report and literature review. World J
14) Rao RN, Agarwal P, Rai P, Kumar B. Isolated desmoid tumor
of pancreatic tail with cyst formation diagnosed by beta-catenin
immunostaining: A rare case report with review of literature.
15) Witkowski G, Kolos M, Nasierowska-Guttmejer A, Durlik M.
Neuroma (schwannoma). A rare pancreatic tumor. Pol Przegl
16) Yavas A, Tan J, Yilmaz F, Reid M, Bagci P, Shi J, Klimstra D,
Basturk O. Solitary fibrous tumor of the pancreas. (Abstract).
2020; The United States and Canadian Academy of Pathology
(USCAP) Annual Meeting. Vancouver, Canada. Mod Pathol.
Abstracts from USCAP. 2020;33:1808-66. 2020: Pancreas,
Gallbladder, Ampulla, and Extra-Hepatic Biliary Tree (1739-
17) Zhang H, Yu S, Wang W, Cheng Y, Xiao Y, Lu Z, Chen J. Primary
mesenchymal tumors of the pancreas in a single center over 15
years. Oncol Lett. 2016;12:4027-34.
18) Poves I, Burdio F, Iglesias M, Martinez-Serrano Mde L, Aguilar
G, Grande L. Resection of the uncinate process of the pancreas
due to a ganglioneuroma. World J Gastroenterol. 2009;15:4334-38.
19) Le Guellec S. Nerve sheath tumours. Ann Pathol. 2015;35:54-70.
20) Gupta A, Subhas G, Mittal VK, Jacobs MJ. Pancreatic
schwannoma: Literature review. J Surg Educ. 2009;66:168-73.
21) Okuma T, Hirota M, Nitta H, Saito S, Yagi T, Ida S, Okamura
S, Chikamoto A, Iyama K, Takamori H, Kanamitsu K, Baba
H. Pancreatic schwannoma: Report of a case. Surg Today.
22) Di Benedetto F, Spaggiari M, De Ruvo N, Masetti M, Montalti
R, Quntini C, Ballarin R, Di Sandro S, Constantini M, Gerunda
GE. Pancreatic schwannoma of the body involving the splenic
vein: case report and review of the literature. Eur J Surg Oncol.
23) Ma Y, Shen B, Jia Y, Luo Y, Tian Y, Dong Z, Chen W, Li ZP,
Feng ST. Pancreatic schwannoma: A case report and an updated
40-year review of the literature yielding 68 cases. BMC Cancer.
24) Zhang H, Jensen MH, Farnell MB, Smyrk TC, Zhang L. Primary
leiomyosarcoma of the pancreas: Study of 9 cases and review of
literature. Am J Surg Pathol. 2010;34:1849-56.
25) Jafri SF, Obaisi O, Vergara GG, Cates J, Singh J, Feeback J,
Yandrapu H. Desmoid type fibromatosis: A case report with an
unusual etiology. World J Gastrointest Oncol. 2017;9:385-89.
26) Amiot A, Dokmak S, Sauvanet A, Vilgrain V, Bringuier PP,
Scoazec JY, Sastre X, Ruszniewski P, Bedossa P, Couvelard
A. Sporadic desmoid tumor. An exceptional cause of cystic
pancreatic lesion. JOP. 2008;9:339-45.
27) Torres JC, Xin C. An unusual finding in a desmoid-type
fibromatosis of the pancreas: A case report and review of the
literature. J Med Case Rep. 2018;12:123.
28) Gerleman R, Mortensen MB, Detlefsen S. Desmoid tumor of
the pancreas: Case report and review of a rare entity. Int J Surg
29) Wang YC, Wong JU. Complete remission of pancreatic head
desmoid tumor treated by COX-2 inhibitor-a case report. World
J Surg Oncol. 2016;14:190.
30) Jia C, Tian B, Dai C, Wang X, Bu X, Xu F. Idiopathic desmoidtype
fibromatosis of the pancreatic head: Case report and
literature review. World J Surg Oncol. 2014;12:103.
31) Anbardar MH, Soleimani N, Aminzadeh Vahedi A, Malek-
Hosseini SA. Large cystic lymphangioma of pancreas mimicking
mucinous neoplasm: Case report with a review of histological
differential diagnosis. Int Med Case Rep J. 2019;12:297-301.
32) Losanoff JE, Richman BW, El-Sherif A, Rider KD, Jones JW.
Mesenteric cystic lymphangioma. J Am Coll Surg. 2003;196:598-
33) Allen JG, Riall TS, Cameron JL, Askin FB, Hruban RH, Campbell
KA. Abdominal lymphangiomas in adults. J Gastrointest Surg.
34) Dodo IM, Adamthwaite JA, Jain P, Roy A, Guillou PJ, Menon
KV. Successful outcome following resection of a pancreatic
liposarcoma with solitary metastasis. World J Gastroenterol.
35) Machado MC, Fonseca GM, de Meirelles LR, Zacchi FF, Bezerra
RO. Primary liposarcoma of the pancreas: A review illustrated by
findings from a recent case. Pancreatology. 2016;16:715-18.
36) Askan G, Bagci P, Hameed M, Basturk O. Dedifferentiated
liposarcoma of the gastroesophageal junction. Turk Patoloji
37) Shirafkan A, Boroumand N, Komak S, Duchini A, Cicalese L.
Pancreatic pleomorphic rhabdomyosarcoma. Int J Surg Case
38) Ogilvie CM, Crawford EA, Slotcavage RL, King JJ, Lackman RD,
Hartner L, Staddon AP. Treatment of adult rhabdomyosarcoma.
Am J Clin Oncol. 2010;33:128-31.
39) Little DJ, Ballo MT, Zagars GK, Pisters PW, Patel SR, El-Naggar
AK, Garden AS, Benjamin RS. Adult rhabdomyosarcoma:
Outcome following multimodality treatment. Cancer.
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