Pancreatic solid cystic desmoid tumor: Case report and literature review

Comprehensive RNA Sequencing Analysis Identifies Network Hub Genes and Biomarkers Differentiating Desmoid-type Fibromatosis From Reactive Fibrosis

Desmoid-type fibromatosis (DTF) is a benign but locally aggressive neoplasm characterized by persistent fibroblast activation, unlike reactive fibrosis (RF), where fibroblast activation is transient. Although the Wnt/β-catenin signaling pathway is known to play a role in DTF pathogenesis, the specific genetic drivers contributing to this abnormal fibroblast activation are not fully understood. To identify additional driver genes that underlie the persistent activation of fibroblasts in DTF, we conducted a comparative transcriptome analysis between 29 DTF and 14 RF tissue samples, identifying 4267 differentially expressed genes (DEGs) specific to DTF. These DTF-specific DEGs were significantly associated with pathways involved in embryonic limb morphogenesis and muscle contraction, whereas RF-specific DEGs were linked to immune response and apoptosis. Using weighted gene coexpression network analysis to further elucidate the key regulatory circuits associated with persistent activation of DTF fibroblasts, we identified a highly DTF-specific gene module comprising 120 genes. This module was also significantly enriched in other fibroproliferative conditions showing persistent fibroblast activation, such as keloid disease and idiopathic pulmonary fibrosis. Subsequent analyses identified 7 driver transcription factors (ZNF536, IRX5, TWIST2, NKD2, PAX9, SHOX2, and SALL4) within this DTF-specific module that may contribute to the sustained activation of DTF fibroblasts. We further assessed the utility of 5 key genes from this module (TWIST2, LRRC15, CTHRC1, SHOX2, and SALL4) as potential biomarkers to distinguish DTF from RF using immunohistochemistry. All markers demonstrated excellent diagnostic performance, with TWIST2 showing exceptionally high sensitivity and specificity, surpassing β-catenin, the current standard biomarker for DTF. In conclusion, our study identifies gene modules and driver transcription factors that are highly specific to DTF, offering new insights into the genetic underpinnings of abnormal fibroblast activation in DTF. We also propose novel biomarkers that could improve the diagnostic accuracy and clinical management of DTF.

Radiological features of pancreatic desmoid-type fibromatosis: a case series and systematic review

PURPOSE

This retrospective study aimed to investigate the radiological features of pancreatic desmoid-type fibromatosis (PDF) and systematically review the previous publications and two new cases.

METHODS

We searched PubMed, Cochrane Library, and Web of Science Core Collection and included 31 patients with pathologically proven PDFs with analyzable preoperative computed tomography (CT) and magnetic resonance imaging, including two patients from our institution and 29 patients from 28 publications. Two board-certified radiologists reviewed all images.

RESULTS

The median age of the patients was 39 years, with a male dominance observed (male, 54.8% vs. female, 45.2%). Abdominal pain was the most frequent symptom, occurring in 58.1% of cases. Surgical resection was performed in all cases of PDFs, resulting in a recurrence rate of 8.3% (2/24). The tumors were most commonly located in the pancreatic tail (23/31, 74.2%). In terms of morphology, a "solid" shape was most prevalent (14/31, 45.2%), followed by a "solid and cystic" shape (9/31, 29.0%) and a "cystic" shape (8/31, 25.8%). Characteristic radiological features included heterogeneous enhancement of the solid portion of the tumors on CT scans (13/20, 65%), moderate-to-weak enhancement in the late phase on CT (16/17, 94.1%), and a presence of cystic components in the tumors (17/31, 54.8%). In 16.1% (5/31) of PDFs, the cystic component was pathologically confirmed to be a dilated pancreatic duct.

CONCLUSION

We summarized the clinical and imaging characteristics of PDF. Although the incidence may not be high, cystic components suggesting a dilated pancreatic duct within the tumor are unique imaging features in PDF.

Large Desmoid Tumor of the Pancreas: A Report of a Rare Case and Review of the Literature

BACKGROUND Desmoid tumor (DT), also known as aggressive fibromatosis or desmoid-type fibromatosis, is a rare disease. It can occur in anyone at any age, and is more likely to appear in female patients. DTs are sometimes associated with familial adenomatous polyposis and rare syndromes such as Gardner syndrome. Arising from specific cells, fibroblasts, they tend to develop in patients with a history of abdominal surgery and rarely produce metastases. CASE REPORT We present a case of a 41-year-old man who was referred for abdominal discomfort with no digestive or general symptoms. An abdominal CT scan revealed a mass in the left hypochondrium, corresponding to an intraperitoneal tumor extending to left colon. Based on MRI, we suspected a gastrointestinal stromal tumor. Colonoscopy showed no intraluminal tumor in the colon. A PET-CT scan revealed tumor hypermetabolism and no metastases. The mass was diagnosed as a DT after percutaneous biopsy. Six weeks after diagnosis and as the tumor continued increasing despite pharmacological treatment, the patient underwent surgical pancreatic tail resection with splenectomy and left colonic segmentectomy. Histological examination revealed a 7.047-g DT with severe infiltration of pancreatic parenchyma and transmural colic barrier, with no high-grade differentiation and negative resection margins. The postoperative recovery was uneventful, and we proposed surveillance with MRI. CONCLUSIONS The DT was surgically removed and patient remains under MRI surveillance. Other reported management approaches consist of radiotherapy, tyrosine kinase inhibitors, anti-hormonal therapies/non-steroidal anti-inflammatory drugs, chemotherapy, or close surveillance only. This is, to our knowledge, the largest and heaviest DT reported in the modern literature.

Intraabdominal sporadic desmoid tumors and inflammation: an updated literature review and presentation and insights on pathogenesis of synchronous sporadic mesenteric desmoid tumors occurring after surgery for necrotizing pancreatitis

Sporadic intra-abdominal desmoid tumors are rare and known to potentially occur after trauma including previous surgery, although knowledge of the underlying pathogenetic mechanism is still limited. We reviewed the recent literature on sporadic intraabdominal desmoids and inflammation as we investigated the mutational and epigenetic makeup of a case of multiple synchronous mesenterial desmoids occurring after necrotizing pancreatitis. A 62-year-old man had four mesenteric masses up to 4.8 cm diameter detected on CT eighteen months after laparotomy for peripancreatic collections from necrotizing pancreatitis. All tumors were excised and diagnosed as mesenteric desmoids. DNA from peripheral blood was tested for a multigene panel. The tumour DNA was screened for three most frequent β-catenin gene mutations T41A, S45F and S45P. Expression levels of miR-21-3p and miR-197-3-p were compared between the desmoid tumors and other wild-type sporadic desmoids. The T41A CTNNB1 mutation was present in all four desmoid tumors. miR-21-3p and miR-197-3p were respectively upregulated and down-regulated in the mutated sporadic mesenteric desmoids, with respect to wild-type lesions. The patient is free from recurrence 34 months post-surgery. The literature review did not show similar studies. To our knowledge, this is the first study to interrogate genetic and epigenetic signature of multiple intraabdominal desmoids to investigate potential association with abdominal inflammation following surgery for necrotizing pancreatitis. We found mutational and epigenetic features that hint at potential activation of inflammation pathways within the desmoid tumor.

Combination of Anlotinib and Celecoxib for the Treatment of Abdominal Desmoid Tumor: A Case Report and Literature Review

Desmoid tumor is a rare disease, which is histologically characterized by local invasion, monoclonality, and fibroblast proliferation; and clinically characterized by a variable and often unpredictable course. The treatment of desmoid tumor is mainly surgical resection, but the recurrence rate is high. In recent years, a variety of treatment methods, including endocrine therapy, surgery, radiotherapy, chemotherapy, non-steroidal anti-inflammatory drugs, targeted drugs, interferon and more, have been used and achieved certain curative effects. In addition, in view of the inertia characteristics of desmoid tumor, observation is also a first-line scheme recommended by multiple guidelines. In the past, the research progress of targeted therapy for desmoid tumor is relatively slow and the curative effect is limited. Thus, targeted therapy is usually used as a remedial treatment after the failure of other conventional treatment methods. However, in recent years, with the rapid progress in the basic research of targeted therapy, some new targeted drugs are increasingly used for the clinical treatment of desmoid tumor and have achieved good results. Herein, we described a patient with aggressive fibromatosis in the abdominal cavity. Following a combined treatment using anlotinib and celecoxib, the patient achieved a partial response with mild toxicity. Simultaneously, the patient’s pain symptoms completely disappeared. This case indicates that the combination of anlotinib and NSAIDs could be an effective treatment for desmoid tumor.

Invasive giant pancreatic desmoid-type fibromatosis with curative resection: A case report

Introduction

Desmoid-type Fibromatoses (DTF) tumours are rare, benign fibrous tumours with aggressive invasive behaviour that account for approximately 0.03% of all neoplasms. We report the success in curing a rare, invasive, and huge pancreatic intraabdominal DTF.

Presentation of case

A 42 years old male was medically free apart from recurrent left upper abdominal pain, anorexia, and nausea for more than ten years and no significant past surgeries, trauma, or family history of cancer. The patient has a non-tender large abdominal mass at the left hypochondria area extending down to the pelvis below the umbilicus with a rigid and smooth surface. The computed tomography scan showed a huge heterogeneous mass appears to be of pancreatic origin, measuring about 23 cm by 15 cm by 11 cm. The patient underwent radical antegrade modular pancreato-splenectomy, segmental transverse colectomy, adrenalectomy, and subsequent colo-colic anastomosis. The accurate gross size of the tumour specimen was 26 × 17 × 9 cm, and the weight was found to be 3.6 kg. Immunohistochemistry confirmed the diagnosis of pancreas DTF. The follow up to 5 years confirmed no recurrence reported clinically or by imaging.

Discussion

The Pancreas origin of DTF is a rarely reported subset with an incidence of around 5% of all DTF. Establishing the diagnosis is fundamentally based on the characteristic pathological and immunohistochemical studies, for the only available cure modality by complete radical resection to be promptly offered.

Conclusion

Our case is rare and uniquely the largest pancreatic DTF reported in the literature with curative resection despite being locally invasive.

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Desmoid-type Fibromatoses (DTF) tumours are rare, benign fibrous tumours with aggressive invasive behaviour.

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Account for approximately 0.03% of all neoplasms.

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The Pancreas is a rarely reported subset with an incidence of around 5% of all DTF.

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Accurate diagnosis is fundamentally by characteristic pathological and immunohistochemical studies.

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Cure can be achieved only by complete radical resection

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We report curative resection of a rare and the largest pancreatic locally invasive DTF (26x17x9 cm in size and weight 3.6Kg)

Desmoid type fibromatosis of the distal pancreas: A case report

A 23-year-old Korean female presented epigastric pain of two-months’ duration. She had a laparoscopic ovarian cyst excision 8 months previously. Clinical examination was normal. An abdominal computed tomogram (CT) demonstrated a 10-cm solid mass in the distal pancreas, with signs of splenic artery and vein occlusion, gastric and transverse colon invasion. Operative findings showed a mass involving distal pancreas, invasive to the posterior wall of the antrum of the stomach and transverse colon and 4th portion of the duodenum without lymph node involvement. The surgery consisted of a distal pancreatectomy, splenectomy and combined partial resection of the stomach, transverse colon and 4th portion of the duodenum. The immunohistochemistry and histopathological features were consistent with a confirmed diagnosis of intra-abdominal desmoid type fibromatosis (DTF). The prognosis of pancreatic DTF is not known and she showed no recurrence or distant metastasis during a 3 year follow-up. Herein we report a rare case with an isolated, sporadic, and non-trauma-related DTF, located at the pancreatic body and tail.

Pancreatic cystic desmoid tumor following metastatic colon cancer surgery: A case report

Desmoid tumors are rare, benign, and locally aggressive neoplasms that stem from connective tissue that have high rates of recurrence after surgery. Intra-abdominal desmoid-type fibromatosis can arise in 2 forms: sporadic or hereditary (associated with familial adenomatous polyposis and Gardner syndrome). The diagnosis of desmoid-type tumors is based on imaging modalities and histopathological examination. The primary treatment is resection surgery. We report a 64-year-old male with a distal pancreatic desmoid tumor. We focus on tumor management by the application of radiological modalities and pathological analysis.

Desmoid fibromatosis of the pancreas--A case report with radiologic-pathologic correlation

Pancreas is an exceptionally rare location for desmoid tumors. There are very few case reports of pancreatic fibromatosis in the English radiology literature. We present a case of a 45-year-old male with a mixed solid and cystic desmoid tumor of the pancreas which was surgically resected and was followed by recurrence in the mesentery. This will be the first case report of pancreatic desmoid with documented recurrence of fibromatosis in the mesentery which was also surgically resected and confirmed on pathology. In this case report, we discuss this entity's radiological findings with pathology correlation, clinical findings and management along with literature review.

A rare sporadic pancreatic desmoid fibromatosis diagnosed by endoscopic ultrasound-guided fine-needle aspiration: Case report and literature review

Intra-abdominal desmoid fibromatosis (also known as desmoid tumor) is a rare benign but often locally aggressive infiltrative fibrous proliferation. Pancreatic desmoid fibromatosis is even rarer, with only 31 cases previously reported in the English-language literature. These tumors present a distinct diagnostic challenge due to their rarity and non-specific image findings and presentation, with most cases diagnosed as desmoid fibromatosis only after surgical resection. This report presents a rare case of pancreatic desmoid fibromatosis in a 72 year old man, who on a follow-up CT for a previously diagnosed angiomyolipoma of the kidney was found to have a 4.0 cm pancreatic tail mass. This was sampled pre-operatively by endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA). Examination of the cytology material showed a low-grade spindle cell lesion. Immunohistochemistry (IHC) performed on FNA cell block showed the lesional cells to be positive for beta-catenin, consistent with fibromatosis. Additional mutational analysis on cell block material revealed the characteristic CTNNB1 gene mutation (T41A), confirming the diagnosis. The mass was then surgically resected and again confirmed to be desmoid fibromatosis on histopathologic examination. On review of previously published cases of pancreatic desmoid fibromatosis, most were initially suspected to be some type of pancreatic neoplasm and were not biopsied prior to surgical resection. This case suggests a potential key role for fine-needle aspiration cytology in the preoperative diagnosis of pancreatic and other intra-abdominal desmoid tumors, particularly as evidence emerges that non-surgical treatment may be a viable first option for some cases.

Laparoscopic spleen-preserving distal pancreatectomy for a solid-cystic intraabdominal desmoid tumor at a gastro-pancreatic lesion: a case report

Background

We report a case of an intraabdominal desmoid tumor that occurred at a gastro-pancreatic lesion with spontaneous cystic features, and present the successful laparoscopic resection of the tumor.

Case presentation

A 20-mm retroperitoneal cystic mass with a solid component was found adjacent to the stomach and pancreatic body in a 52-year-old woman with no history of familial adenomatous polyposis. Laparoscopic spleen-preserving distal pancreatectomy with wedge resection of the stomach was performed, and complete resection was achieved without intraoperative and postoperative complications. Histopathological examination by immunohistochemistry enabled diagnosis of a desmoid tumor that had originated from the stomach and invaded the pancreatic parenchyma with a spontaneous cystic change. We herein report an extremely rare case of an intraabdominal desmoid tumor with a spontaneous cystic change.

Conclusion

Regardless of its rarity, desmoid tumor should be included in the preoperative differential diagnosis of a cystic intraabdominal mass, and laparoscopic function-preserving surgery may be an optimal treatment option.

An Intra-abdominal Solid-cystic Desmoid That Emerged after Distal Gastrectomy

Desmoid is a locally aggressive fibroblastic neoplasm, typically showing a heterogeneous solid mass, and its pathogenesis is multifactorial, including surgical scars. We herein report a rare case of an intra-abdominal desmoid, consisting of solid and cystic components covered with epithelial linings, that emerged after distal gastrectomy. The preoperative diagnosis was inconclusive, so laparotomy was performed. Histopathology of the solid component showed proliferating spindle cells, which were positive for beta-catenin in their nuclei. Clinicians need to bear in mind that desmoids can appear in a solid-cystic form, and immunostaining of beta-catenin should be applied for tumors that emerge around postoperative wounds.

Desmoid-type fibromatosis mimicking cystic retroperitoneal mass: case report and literature review

Background

Retroperitoneal desmoid-type fibromatosis (DF) is an uncommon mesenchymal neoplasm presenting as a firm mass with locally aggressive features. It usually manifests as a well-circumscribed or ill-defined, solid mass on cross-sectional imaging. Cystic changes of DF have been described in the literature in association with prolonged medical treatment or abscess formation. However, spontaneous cystic change is rarely reported.

Case presentation

Here we report the case of a 46-year-old patient with a DF mimicked a large cystic tumor in the retroperitoneum. Ultrasonography and computed tomography were performed in order to search for localizations and characteristics of the cystic tumor. Radiological findings showed an oval cystic mass with a relatively thick wall, measuring 18.3 × 12.3 × 21.5 cm in the left upper abdomen. Laparoscopic spleen-preserving distal pancreatectomy was performed and histopathological examination by immunohistochemical study enabled us to diagnose a DF invading the pancreatic parenchyma. The patient remained asymptomatic during an 8-month follow up period.

Conclusions

We report an extremely rare case of retroperitoneal DF with spontaneous cystic change. DF can manifest as a mainly cystic mass with a thick wall, as in our case, which makes the correct diagnosis difficult. DF should be included in the preoperative differential diagnosis of a cystic retroperitoneal mass, regardless of its rarity.

Pancreatic desmoid tumor: A rare case with radiologic-pathologic correlation

A 39-year-old female patient was referred to our tertiary oncologic center for additional investigations relating to a suspect pancreatic tail lesion. An abdominal computed tomography scan and magnetic resonance imaging scan showed a solid lesion demonstrating progressive enhancement. Complete resection was obtained and the final diagnosis was that of a desmoid tumor of the pancreas, an exceptionally rare tumor demonstrating overlap with other solid and cystic lesions of the pancreas [1]. Therefore, it is important to recognize the essential role of pathology, particularly immunohistochemistry, in identifying this tumor. The high rate of postsurgical recurrence should prompt repeated follow-ups considering the potential aggressive nature of desmoid tumors.

An unusual finding in a desmoid-type fibromatosis of the pancreas: a case report and review of the literature

Background

Desmoid-type fibromatoses are rare benign and fibrous tumors that account for approximately 0.03% of total neoplasms. Within this category of neoplasms, pancreatic desmoid-type fibromatosis is an extremely rare subgroup, accounting for approximately 5% of desmoid-type fibromatoses. Although the etiology is unknown, some risk factors include trauma, surgery, family history of desmoid tumor, pregnancy, use of contraceptives, genetic mutation, and familial adenomatous polyposis or Gardner syndrome. Desmoid-type tumors are primarily diagnosed by pathological and immunohistochemical studies. The treatment of choice is surgical resection of the tumor. Systemic chemotherapy and radiotherapy are optional treatment approaches for patients with high risk for surgery.

The following is a report of an unusual case of a pancreatic desmoid-type fibromatosis in which a very rare variation in the immunohistochemistry findings was demonstrated: slides were immunopositive for S100 protein and not immunonegative. Most desmoid tumors are immunonegative for S100 protein with just a few cases being positive for this protein.

Case presentation

We describe the case of a 15-year-old boy, a Chinese national, who was diagnosed as having a pancreatic desmoid-type fibromatosis. He was a healthy individual who was incidentally diagnosed with an abdominal mass. His chief complaints were mild generalized abdominal pain for 1 week, nausea, vomiting, and a low-grade fever. An enhanced computed tomography scan of his abdomen showed a large cystic mass in the anterior surface of the body of his pancreas. He underwent a radical resection of the pancreatic mass, partial pancreatectomy, splenectomy, segmental resection of transverse colon and distal jejunum, and subsequently a one-stage jejunojejunostomy and colonic anastomosis. Postoperatively, he was diagnosed as having a desmoid-type fibromatosis of the pancreas by pathological and immunohistochemical studies.

Conclusions

The diagnosis of desmoid-type fibromatosis is usually incidental and challenging. Pathological and immunohistochemical testing are essential for confirming diagnosis where demonstration of β-catenin nuclear staining is probably the single most important characteristic. Other markers, such as vimentin, are usually positive, while S100 protein is usually negative. Our case however, confirms that there are rare cases that can be S100 positive. This is the first diagnosed case of pancreatic desmoid-type fibromatosis with S100 protein positivity.

Rare pancreatic tumors

In this review, we will focus on rare pancreatic tumors. Most of these tumors do not have distinct characteristic appearances so the key to diagnosis requires a combination of imaging appearance, laboratory data, patient demographics, and associated medical syndromes in order to narrow the differential diagnosis. Nonetheless, imaging plays a vital role in narrowing the differential and guiding management. While there are many variant pathologic entities that cannot be encompassed by a single review, we aim to illustrate the imaging appearance of less common pancreatic tumors highlighting key distinctive diagnostic characteristics and discuss the implications for management. While there is overlap in the imaging appearances of many of these entities, for educational purposes, lesions will be categorized into solid (hypoenhancing and hyperenhancing), cystic lesions, mesenchymal neoplasms, and neoplasms seen in younger patients (< 40 years).

Primary mesenchymal tumors of the pancreas in a single center over 15 years

In total, 95% of primary tumors in the pancreas are epithelial tumors; primary mesenchymal tumors at this site are extremely rare. At present, only one comprehensive study about these rare tumors has been performed. Another retrospective analysis of these rare tumors is performed in the present study, which, to the best of our knowledge, is the first to be performed in China. In the present study, 10 patients that underwent resection for primary mesenchymal tumors of the pancreas were identified in a 15-year period at the Chinese Academy of Medical Sciences and Peking Union Medical College, which accounted for 0.51% of the total surgically resected primary tumors of the pancreas at this hospital. Among the 10 patients, 7 patients (70%) were diagnosed with benign/borderline tumors, and the remaining 3 patients (30%) were diagnosed with malignant tumors. It was a unique finding of the present study that the preoperative diagnosis was frequently a misdiagnosis, in terms of the specific pathological diagnosis. Therefore, although primary mesenchymal tumors of the pancreas are extremely rare, they should be considered in order to make the correct preoperative diagnosis. Contrarily to a previous study, in the present study, the most common benign tumor was not desmoid tumor, but solitary fibrous tumors; the most frequent primary sarcoma was not undifferentiated/unclassified sarcoma either. In conclusion, the present study aids the understanding of these rare tumors; however, primary mesenchymal tumors of the pancreas require additional exploration in the future.

Complete remission of pancreatic head desmoid tumor treated by COX-2 inhibitor-a case report

Background

Desmoid tumors (DTs) are non-metastatic, locally aggressive neoplasms with high postoperative recurrence rates. The pancreas is an extremely rare location for DTs. The local control of DTs is challenging. Surgery and radiotherapy are currently the principal treatment modalities for DTs; however, some resections might not be radical, and radiotherapy has several drawbacks. Therefore, many studies have been focusing on the molecular pathways involved in DTs in order to develop molecular-targeted therapies or chemotherapy. Cyclooxygenase-2 (COX-2) has been demonstrated to play a role in the growth of DTs, and the pharmacologic blockade of COX resulted in decreased cell proliferation in desmoid cell cultures in vitro.

Case presentation

Herein, we report a 57-year-old woman who presented with recurrent epigastric pain and weight loss. An abdominal computed tomography scan showed an approximately 10-cm mass over the pancreatic head region and dilatation of the pancreatic duct. Tumor biopsy and bypass surgery were performed. A DT was confirmed on pathologic analysis. After resection, we prescribed treatment with the COX-2 inhibitor celecoxib. The patient showed complete remission and there was no local recurrence or distant metastasis within the 24-month follow-up period.

Conclusions

The outcome of this case study is encouraging, and long-term follow-up studies are required to establish the effect of treatment with celecoxib on the prognosis of DTs.

Pancreatic desmoid-type fibromatosis with beta-catenin gene mutation-Report of a case and review of the literature

We experienced a rare case of pancreatic desmoid-type fibromatosis (DTF) in a 75-year-old Japanese woman. She was asymptomatic but routine examination including ultrasonography revealed a mass in the abdomen. For precise examination, she was referred to the regional hospital. Computed tomography showed that the mass was protruding anteriorly from the left-sided pancreas. Because of the enlargement of the mass lesion, distal pancreatectomy with splenectomy was performed after about 3 months. Macroscopically, the mass was encapsulated and approximately 8cm in diameter. Histological examination revealed that spindle or blunt stellate cells were proliferating in parallel or storiform fashion with myxoid and fibrous background. The tumor cells did not show prominent atypia and mitoses were rarely seen, suggesting that the tumor was low grade or borderline. Immunohistochemistry showed obvious nuclear staining of beta-catenin. Furthermore, analysis of beta-catenin gene revealed that the tumor had a typical missense mutation of threonine to alanine at colon 41 (T41A) in exon 3. These findings confirmed the pathological diagnosis of DTF of the pancreas. To the best of our knowledge, 18 cases of pancreatic DTF have been reported in the English literature and beta-catenin gene mutation had been examined in only one case among them. Thus, our case is the 19th pancreatic DTF and the second case with confirmed beta-catenin gene mutation.

Desmoid Tumor of the Pancreas

Desmoid tumors, also known as desmoid-type fibromatoses or aggressive fibromatoses, are clonal fibroblastic proliferations that arise in the deep soft tissues. They are characterized by infiltrative growth, a tendency toward local recurrence and the inability to metastasize. We present a case of a 63-year-old woman who complained of abdominal pain, and a contrast-enhanced computed tomography scan revealed a well-circumscribed tumor in the pancreatic tail, measuring 5.1 cm. A left-sided, spleen-preserving pancreatic resection was performed, and pathological analysis showed a mesenchymal tumor. The diagnosis of a pancreatic desmoid tumor was made based on the characteristic morphology and the immune phenotype of the tumor. The English-language literature on pancreatic desmoid tumors was reviewed. In total, 16 previous cases were identified.