Indian J Surg Oncol (March 2016) 7(1):82–85 DOI 10.1007/s13193-015-0454-4
CASE REPORT
Plexiform Angiomyxoid Myofibroblastic Tumor (PAMT) of Stomach with Synchronous Bilateral Cystic Ovarian Neoplasms, a Rare Case Presentation Jagannath Dattatreya Dixit 1 & Shiraz Ahamed Sharief 2 & Manish Kumar Goyal 1 & Sameeha Khan 2 & Lubna Kauser 3
Received: 22 January 2015 / Accepted: 17 August 2015 / Published online: 26 August 2015 # Indian Association of Surgical Oncology 2015
Abstract Plexiform Angiomyxoid Myofibroblastic Tumor (PAMT) is a recently identified mesenchymal tumor of the stomach, which was first described in the year 2007 and was added in the 2010 WHO classification of tumors of the digestive system World J Gastroenterol 16(6): 2835–2840, 2010. It closely resembles with other gastric tumors but distinctly varies in clinical management as well as the histopathology. We had a 51 year, female patient, laborer by profession with low socio economic status, who had abdominal pain with vomiting since 6 months. She had similar complaints 3 years ago for which she was evaluated and presumed to have Carcinoma Stomach and underwent laparotomy which ended up only with Gastro- Jejunal anastomosis. She was admitted at our institution. Endoscopy revealed antral bulge with central area ulceration and biopsy was taken which was not confirmatory for malignancy. CT images showed heterogeneous mass with necrotic changes arising from the duodenum favored the diagnosis of perigastric neoplasm. PET CT was done, 8.4×5×6.1 cm exophytic mass in the pyloric region of stomach with solid and cystic components causing significant gastric outlet obstruction. She underwent exploratory laparotomy and complete excision of mass with achievement of R0 clearance. Histopathology was reported as Plexiform angiomyxoid myofibroblastic tumor (PAMT).
Keywords Stomach tumour . WHO classification . Gastric outlet obstruction . PET CT scan . Ovarian neoplasms . * Shiraz Ahamed Sharief [email protected] 1
HCG-Bangalore Institute of Oncology, Bengaluru, Karnataka, India
2
Al-Ameen Medical College, Vijayapur, Karnataka, India
3
Sri Siddhartha Medical College, Tumakuru, Karnataka, India
Laparotomy . Gastro jejunostomy . Rare disease . Histopathology . Immuno-histochemistry
Introduction Plexiform Angiomyxoid Myofibroblastic Tumor (PAMT) is a recently identified mesenchymal tumor of the stomach, which was first described in the year 2007 and was added in the 2010 WHO classification of tumors of the digestive system [1]. It closely resembles with other gastric tumors but distinctly varies in clinical management as well as the histopathology and immunohistochemistry. We had a 51 year old female patient with intermittent abdominal pain associated with vomiting and weight loss since 6 months. She had similar complaints in the past and underwent laparotomy with gastro-jejunal anastomosis at a different institution. A detailed evaluation was done at our hospital, with upper GI endoscopic biopsy, PET CT study and blood investigations. She underwent exploratory laparotomy and complete excision of mass with achievement of R0 clearance. Histopathology and immunohistochemistry assessment revealed Plexiform Angiomyxoid Myofibroblastic Tumor (PAMT) of Stomach.
Case Report We present an interesting case report of a 51 year old woman, daily wage worker from a rural background, with a 6 months history of intermittent abdominal pain with vomiting and weight loss. There was no history of hematemesis and malaena. She had a past history of laparotomy which was performed 3 years ago at a different institution whose discharge summary revealed an unresectable distal gastric tumour for which gastro-
Indian J Surg Oncol (March 2016) 7(1):82–85
83
jejunostomy was done. On examination, she appeared emaciated with an abdominal midline scar and non-tender, vague masses in the epigastrium and the lower abdominal quadrants. A detailed evaluation was done at our institution for a suspected gastric malignancy. Upper GI endoscopy revealed a status-post gastrojejunostomy site with an antral bulge of 4x6cm with smooth surface and central area ulceration. Biopsy was taken and was not confirmatory for malignancy as it showed only myxoid changes on histopathology. CT images of abdomen revealed an 8.4×5×6.1 cm predominantly exophytic mass in the pylorus of stomach with solid and cystic / necrotic components causing gastric outlet obstruction.
Significant strandings with nodularity in the gastro-hepatic ligament and transverse mesocolon were also seen. In addition to this bilateral multiloculated ovarian cystic neoplasms measuring 8.7×5.4 cm on the left and 6.6×3.6 cm on the right were noticed. In this case, contrast-enhanced CT images revealed a pyloric mass with a heterogeneous, prominent enhancement in the late phase of contrast imaging. She was further evaluated with FDG PET-CT scan, which showed lower levels of Standard Uptake Values of the pyloric mass (SUV 5.3) and adnexal regions (SUV 2.9) (Fig. 1). CA125 levels were within the normal levels. Consent was taken for exploratory laparotomy with or without distal gastrectomy only as the patient was not willing for hysterectomy with
Fig. 1 PET CT images of abdomen showing a predominantly exophytic mass in the pylorus of stomach, with solid and cystic / necrotic components and uptake of SUV 5.3, measuring 8.4×5×6.1 cm causing near total gastric outlet obstruction with a previously performed Gastro-
Jejunostomy . Below image, CT pelvis showing bilateral multi loculated ovarian cystic neoplasms measuring 8.7×5.4 cm on the left and 6.6× 3.6 cm on the right
84
bilateral salpingo-oophorectomy. Exploratory laparotomy was done using midline skin incision. Adhesions were released. Distal gastrectomy was done using linear cutting staplers, without disturbing the previous gastro-jejunostomy site (Fig. 2) . Specimen was sent for histopathology (Fig. 3). Fluid from the left paracolic gutter was taken for cytology. Abdominal wash given and drain was placed. The wound was closed in layers . Histo pathology report and immuno-histochemistry features supported the diagnosis of Plexiform Angiomyxoid Myofibroblastic Tumor (PAMT). Histological examination showed extension of tumour from the submucosa to the serosa. The tumour exhibited an irregular multinodular plexiform pattern. The cells were spindle-shaped, with no significant nuclear atypia or mitosis, and were disposed randomly or in a vague fascicular fashion, separated by an abundant myxoid extracellular matrix that was alcian blue (pH 2.5) positive and in which a network of fine capillary caliber arborizing vessels was observed (Fig. 3). Stromal collagenisation was also noted. Tumor necrosis was not observed. On immunohistochemistry, the tumor cells were diffusely positive for α-smooth muscle actin (SMA), but negative for CD117, CD34, S-100 protein, anaplastic lymphoma kinase (ALK), β-catenin, and H-caldesmon [4, 5]. The Ki67 labeling index was less than 1 %. Based on the histological features, and supported by the immunostaining findings, a diagnosis of PAMT was confirmed. Patient recovered well in the post-operative period. She was allowed to take orally on 5th post-operative day and subsequently the drain was removed. She was discharged on the 7th post-operative day.
Discussion Takahashi et al. described 2 cases of a unique gastric mesenchymal tumor designated as “Plexiform Angiomyxoid
Fig. 2 Cut surface of the distal stomach showing antral bulge and nodularity with well-circumscribed polypoidal tumor measuring 7.0 cm×4.0 cm×3.0 cm in the anterior antral wall
Indian J Surg Oncol (March 2016) 7(1):82–85
Fig. 3 Gross pathological specimen in cut section, showing the cystic and degenerative solid components with glistening translucid tumour., below microscopic image showing the fascicular arrangements of Spindle cells separated by an abundant myxoid extracellular matrix
Myofibroblastic Tumour (PAMT)” in 2007 [2]. Two years later, Miettinen et al. described a series of similar tumors, and they advocated the use of the appellation “plexiform fibromyxoma” and estimated that the frequency of PAMT is less than 1/150 that of GIST [4, 5]. Till now only 29 cases of Plexiform Angiomyxoid Myofibroblastic Tumour (PAMT) have been reported, including our present case .The prevalence rate of PAMT are not dependent upon the gender with almost equal distribution among the sexes (M:F=13:16).The average tumor size varies in range (1.5–15 cm), but most are a few cm in size (mean: 6.0 cm) [1, 2]. Typical histological features of this entity include multinodular plexiform growth pattern, spindle-shape bland myofibroblastic tumor cells positive for smooth muscle actin (SMA) and myxoid matrix that is rich in small vessels, but fibrosis or collagenous matrix is only observed in some cases [5]. Therefore, we believe PAMT is an appropriate diagnostic term to cover histogenesis and histology. However, the WHO classification of tumors of the digestive system accepted “plexiform fibromyxoma” as a diagnostic term instead of PAMT [6]. Although PAMT demonstrates characteristic pathological features, it should be considered in the differential diagnosis of gastrointestinal stromal tumors (GIST) and other mesenchymal tumors of the stomach, such as leiomyoma, schwannoma, perineurioma, fibromatosis, solitary fibrous tumor,
Indian J Surg Oncol (March 2016) 7(1):82–85
inflammatory fibroid polyp, and inflammatory myofibroblastic tumor [3, 8]. The application of an appropriate panel of antibodies and awareness of PAMT should result in the correct diagnosis being made [3]. Due to its rarity, the true biological potential of PAMT remains unknown. However, the bland nuclear features, low proliferative index and absence of necrosis, vascular invasion, recurrence or metastasis in all PAMT cases reported to date justify its characterization as a benign tumor [2, 4] but association of this with cystic ovarian disease is of true concern. Currently, complete excision remains the treatment of choice [1].
Conclusion Plexiform Angiomyxoid Myofibroblastic Tumour (PAMT) of the stomach is a very rare tumor without distinctive clinical manifestations. Symptoms may include those of ulceration, hematemesis and anemia [2], our patient presented with intermittent epigastric discomfort and abdominal pain. Usually the endoscopist encounters a submucosal based or nodular mass [9]. A very striking feature is the almost exclusive location in the gastric antrum [3, 4]. The mucosa may be intact, dimpled or ulcerated [3, 9]. Imaging has a difficult role to distinguish it from other stromal tumours [7]. Although this case was diagnosed upon post-surgical histopathology, we recommend that, when myxoid spindle cell lesion is observed in endoscopic biopsy, PAMT should be included in diferential diagnosis [9]. Even though there are about 29 published cases of PAMT, association of this entity with bilateral cystic ovarian neoplasms may be the rarest among rare combinations and has a great concern in surgical oncology.
85 Acknowledgments Dr.Aparna Ganguly, Department of Surgical OncoPathology, HCG Hospital, Bengaluru. Dr.Nishikant Namdev Gujar, Professor of Surgery, Al Ameen Medical College, Vijayapur. Dr.Lubna Kauser, Sri Siddhartha Medical College, Tumakuru. Conflict of Interest None
References 1.
Takahashi Y, Suzuki M, Fukusato T (2010) Plexiform angiomyxoid myofibroblastic tumor of the stomach. World J Gastroenterol 16(23): 2835–2840. doi:10.3748/wjg.v16.i23.2835 2. Takahashi Y, Shimizu S, Ishida T, Aita K, Toida S, Fukusato T, Mori S (2007) Plexiform angiomyxoid myofibroblastic tumor of the stomach. Am J Surg Pathol 31(5):724–728. doi:10.1097/01.pas. 0000213448.54643.2f 3. Kim A, Bae YK, Shin HC, Choi JH (2011) Plexiform angiomyxoid myofibroblastic tumor of the stomach: a case report. J Korean Med Sci 26(11):1508–1511. doi:10.3346/jkms.2011.26.11.1508 4. Wang LM, Chetty R (2012) Selected unusual tumors of the stomach: a review. Int J Surg Pathol 20(1):5–14. doi:10.1177/ 1066896911429300 5. Miettinen M, Makhlouf HR, Sobin LH, Lasota J (2009) Plexiform fibromyxoma: a distinctive benign gastric antral neoplasm not to be confused with a Myxoid GIST. Am J Surg Pathol 33(11):1624–1632. doi:10.1097/PAS.0b013e3181ae666a 6. Miettinen M, Fletcher CD, Kindblom LG, WM T (2010) Mesenchymal tumours of the stomach. In: Bosman FT, Carneiro F, Hruban R, Teise ND (eds) WHO classification of tumours of the digestive system. IARC, Lyon, p 417, NLM ID 101553728 7. Ghanem N, Altehoefer C, Furtwängler A, Winterer J, Schäfer O, Springer O, Kotter E, Langer M (2003) Computed tomography in gastrointestinal stroma tumors. Eur Radiol 13:1669–1678 8. Rau TT, Hartmann A, Dietmaier W, Schmitz J, Hohenberger W, Hofstaedter F, Katenkamp K (2008) Plexiform angiomyxoid myofibroblastic tumour: differential diagnosis of gastrointestinal stromal tumour in the stomach. J Clin Pathol 61:1136–1137 9. Wang WY, Li JN, Li GD (2010) Plexiform angiomyxoid myofibroblastic tumour of the gastric fundus: successful diagnosis and treatment by endoscopy. J Clin Pathol 63:569–570
CASE REPORT
Plexiform Angiomyxoid Myofibroblastic Tumor (PAMT) of Stomach with Synchronous Bilateral Cystic Ovarian Neoplasms, a Rare Case Presentation Jagannath Dattatreya Dixit 1 & Shiraz Ahamed Sharief 2 & Manish Kumar Goyal 1 & Sameeha Khan 2 & Lubna Kauser 3
Received: 22 January 2015 / Accepted: 17 August 2015 / Published online: 26 August 2015 # Indian Association of Surgical Oncology 2015
Abstract Plexiform Angiomyxoid Myofibroblastic Tumor (PAMT) is a recently identified mesenchymal tumor of the stomach, which was first described in the year 2007 and was added in the 2010 WHO classification of tumors of the digestive system World J Gastroenterol 16(6): 2835–2840, 2010. It closely resembles with other gastric tumors but distinctly varies in clinical management as well as the histopathology. We had a 51 year, female patient, laborer by profession with low socio economic status, who had abdominal pain with vomiting since 6 months. She had similar complaints 3 years ago for which she was evaluated and presumed to have Carcinoma Stomach and underwent laparotomy which ended up only with Gastro- Jejunal anastomosis. She was admitted at our institution. Endoscopy revealed antral bulge with central area ulceration and biopsy was taken which was not confirmatory for malignancy. CT images showed heterogeneous mass with necrotic changes arising from the duodenum favored the diagnosis of perigastric neoplasm. PET CT was done, 8.4×5×6.1 cm exophytic mass in the pyloric region of stomach with solid and cystic components causing significant gastric outlet obstruction. She underwent exploratory laparotomy and complete excision of mass with achievement of R0 clearance. Histopathology was reported as Plexiform angiomyxoid myofibroblastic tumor (PAMT).
Keywords Stomach tumour . WHO classification . Gastric outlet obstruction . PET CT scan . Ovarian neoplasms . * Shiraz Ahamed Sharief [email protected] 1
HCG-Bangalore Institute of Oncology, Bengaluru, Karnataka, India
2
Al-Ameen Medical College, Vijayapur, Karnataka, India
3
Sri Siddhartha Medical College, Tumakuru, Karnataka, India
Laparotomy . Gastro jejunostomy . Rare disease . Histopathology . Immuno-histochemistry
Introduction Plexiform Angiomyxoid Myofibroblastic Tumor (PAMT) is a recently identified mesenchymal tumor of the stomach, which was first described in the year 2007 and was added in the 2010 WHO classification of tumors of the digestive system [1]. It closely resembles with other gastric tumors but distinctly varies in clinical management as well as the histopathology and immunohistochemistry. We had a 51 year old female patient with intermittent abdominal pain associated with vomiting and weight loss since 6 months. She had similar complaints in the past and underwent laparotomy with gastro-jejunal anastomosis at a different institution. A detailed evaluation was done at our hospital, with upper GI endoscopic biopsy, PET CT study and blood investigations. She underwent exploratory laparotomy and complete excision of mass with achievement of R0 clearance. Histopathology and immunohistochemistry assessment revealed Plexiform Angiomyxoid Myofibroblastic Tumor (PAMT) of Stomach.
Case Report We present an interesting case report of a 51 year old woman, daily wage worker from a rural background, with a 6 months history of intermittent abdominal pain with vomiting and weight loss. There was no history of hematemesis and malaena. She had a past history of laparotomy which was performed 3 years ago at a different institution whose discharge summary revealed an unresectable distal gastric tumour for which gastro-
Indian J Surg Oncol (March 2016) 7(1):82–85
83
jejunostomy was done. On examination, she appeared emaciated with an abdominal midline scar and non-tender, vague masses in the epigastrium and the lower abdominal quadrants. A detailed evaluation was done at our institution for a suspected gastric malignancy. Upper GI endoscopy revealed a status-post gastrojejunostomy site with an antral bulge of 4x6cm with smooth surface and central area ulceration. Biopsy was taken and was not confirmatory for malignancy as it showed only myxoid changes on histopathology. CT images of abdomen revealed an 8.4×5×6.1 cm predominantly exophytic mass in the pylorus of stomach with solid and cystic / necrotic components causing gastric outlet obstruction.
Significant strandings with nodularity in the gastro-hepatic ligament and transverse mesocolon were also seen. In addition to this bilateral multiloculated ovarian cystic neoplasms measuring 8.7×5.4 cm on the left and 6.6×3.6 cm on the right were noticed. In this case, contrast-enhanced CT images revealed a pyloric mass with a heterogeneous, prominent enhancement in the late phase of contrast imaging. She was further evaluated with FDG PET-CT scan, which showed lower levels of Standard Uptake Values of the pyloric mass (SUV 5.3) and adnexal regions (SUV 2.9) (Fig. 1). CA125 levels were within the normal levels. Consent was taken for exploratory laparotomy with or without distal gastrectomy only as the patient was not willing for hysterectomy with
Fig. 1 PET CT images of abdomen showing a predominantly exophytic mass in the pylorus of stomach, with solid and cystic / necrotic components and uptake of SUV 5.3, measuring 8.4×5×6.1 cm causing near total gastric outlet obstruction with a previously performed Gastro-
Jejunostomy . Below image, CT pelvis showing bilateral multi loculated ovarian cystic neoplasms measuring 8.7×5.4 cm on the left and 6.6× 3.6 cm on the right
84
bilateral salpingo-oophorectomy. Exploratory laparotomy was done using midline skin incision. Adhesions were released. Distal gastrectomy was done using linear cutting staplers, without disturbing the previous gastro-jejunostomy site (Fig. 2) . Specimen was sent for histopathology (Fig. 3). Fluid from the left paracolic gutter was taken for cytology. Abdominal wash given and drain was placed. The wound was closed in layers . Histo pathology report and immuno-histochemistry features supported the diagnosis of Plexiform Angiomyxoid Myofibroblastic Tumor (PAMT). Histological examination showed extension of tumour from the submucosa to the serosa. The tumour exhibited an irregular multinodular plexiform pattern. The cells were spindle-shaped, with no significant nuclear atypia or mitosis, and were disposed randomly or in a vague fascicular fashion, separated by an abundant myxoid extracellular matrix that was alcian blue (pH 2.5) positive and in which a network of fine capillary caliber arborizing vessels was observed (Fig. 3). Stromal collagenisation was also noted. Tumor necrosis was not observed. On immunohistochemistry, the tumor cells were diffusely positive for α-smooth muscle actin (SMA), but negative for CD117, CD34, S-100 protein, anaplastic lymphoma kinase (ALK), β-catenin, and H-caldesmon [4, 5]. The Ki67 labeling index was less than 1 %. Based on the histological features, and supported by the immunostaining findings, a diagnosis of PAMT was confirmed. Patient recovered well in the post-operative period. She was allowed to take orally on 5th post-operative day and subsequently the drain was removed. She was discharged on the 7th post-operative day.
Discussion Takahashi et al. described 2 cases of a unique gastric mesenchymal tumor designated as “Plexiform Angiomyxoid
Fig. 2 Cut surface of the distal stomach showing antral bulge and nodularity with well-circumscribed polypoidal tumor measuring 7.0 cm×4.0 cm×3.0 cm in the anterior antral wall
Indian J Surg Oncol (March 2016) 7(1):82–85
Fig. 3 Gross pathological specimen in cut section, showing the cystic and degenerative solid components with glistening translucid tumour., below microscopic image showing the fascicular arrangements of Spindle cells separated by an abundant myxoid extracellular matrix
Myofibroblastic Tumour (PAMT)” in 2007 [2]. Two years later, Miettinen et al. described a series of similar tumors, and they advocated the use of the appellation “plexiform fibromyxoma” and estimated that the frequency of PAMT is less than 1/150 that of GIST [4, 5]. Till now only 29 cases of Plexiform Angiomyxoid Myofibroblastic Tumour (PAMT) have been reported, including our present case .The prevalence rate of PAMT are not dependent upon the gender with almost equal distribution among the sexes (M:F=13:16).The average tumor size varies in range (1.5–15 cm), but most are a few cm in size (mean: 6.0 cm) [1, 2]. Typical histological features of this entity include multinodular plexiform growth pattern, spindle-shape bland myofibroblastic tumor cells positive for smooth muscle actin (SMA) and myxoid matrix that is rich in small vessels, but fibrosis or collagenous matrix is only observed in some cases [5]. Therefore, we believe PAMT is an appropriate diagnostic term to cover histogenesis and histology. However, the WHO classification of tumors of the digestive system accepted “plexiform fibromyxoma” as a diagnostic term instead of PAMT [6]. Although PAMT demonstrates characteristic pathological features, it should be considered in the differential diagnosis of gastrointestinal stromal tumors (GIST) and other mesenchymal tumors of the stomach, such as leiomyoma, schwannoma, perineurioma, fibromatosis, solitary fibrous tumor,
Indian J Surg Oncol (March 2016) 7(1):82–85
inflammatory fibroid polyp, and inflammatory myofibroblastic tumor [3, 8]. The application of an appropriate panel of antibodies and awareness of PAMT should result in the correct diagnosis being made [3]. Due to its rarity, the true biological potential of PAMT remains unknown. However, the bland nuclear features, low proliferative index and absence of necrosis, vascular invasion, recurrence or metastasis in all PAMT cases reported to date justify its characterization as a benign tumor [2, 4] but association of this with cystic ovarian disease is of true concern. Currently, complete excision remains the treatment of choice [1].
Conclusion Plexiform Angiomyxoid Myofibroblastic Tumour (PAMT) of the stomach is a very rare tumor without distinctive clinical manifestations. Symptoms may include those of ulceration, hematemesis and anemia [2], our patient presented with intermittent epigastric discomfort and abdominal pain. Usually the endoscopist encounters a submucosal based or nodular mass [9]. A very striking feature is the almost exclusive location in the gastric antrum [3, 4]. The mucosa may be intact, dimpled or ulcerated [3, 9]. Imaging has a difficult role to distinguish it from other stromal tumours [7]. Although this case was diagnosed upon post-surgical histopathology, we recommend that, when myxoid spindle cell lesion is observed in endoscopic biopsy, PAMT should be included in diferential diagnosis [9]. Even though there are about 29 published cases of PAMT, association of this entity with bilateral cystic ovarian neoplasms may be the rarest among rare combinations and has a great concern in surgical oncology.
85 Acknowledgments Dr.Aparna Ganguly, Department of Surgical OncoPathology, HCG Hospital, Bengaluru. Dr.Nishikant Namdev Gujar, Professor of Surgery, Al Ameen Medical College, Vijayapur. Dr.Lubna Kauser, Sri Siddhartha Medical College, Tumakuru. Conflict of Interest None
References 1.
Takahashi Y, Suzuki M, Fukusato T (2010) Plexiform angiomyxoid myofibroblastic tumor of the stomach. World J Gastroenterol 16(23): 2835–2840. doi:10.3748/wjg.v16.i23.2835 2. Takahashi Y, Shimizu S, Ishida T, Aita K, Toida S, Fukusato T, Mori S (2007) Plexiform angiomyxoid myofibroblastic tumor of the stomach. Am J Surg Pathol 31(5):724–728. doi:10.1097/01.pas. 0000213448.54643.2f 3. Kim A, Bae YK, Shin HC, Choi JH (2011) Plexiform angiomyxoid myofibroblastic tumor of the stomach: a case report. J Korean Med Sci 26(11):1508–1511. doi:10.3346/jkms.2011.26.11.1508 4. Wang LM, Chetty R (2012) Selected unusual tumors of the stomach: a review. Int J Surg Pathol 20(1):5–14. doi:10.1177/ 1066896911429300 5. Miettinen M, Makhlouf HR, Sobin LH, Lasota J (2009) Plexiform fibromyxoma: a distinctive benign gastric antral neoplasm not to be confused with a Myxoid GIST. Am J Surg Pathol 33(11):1624–1632. doi:10.1097/PAS.0b013e3181ae666a 6. Miettinen M, Fletcher CD, Kindblom LG, WM T (2010) Mesenchymal tumours of the stomach. In: Bosman FT, Carneiro F, Hruban R, Teise ND (eds) WHO classification of tumours of the digestive system. IARC, Lyon, p 417, NLM ID 101553728 7. Ghanem N, Altehoefer C, Furtwängler A, Winterer J, Schäfer O, Springer O, Kotter E, Langer M (2003) Computed tomography in gastrointestinal stroma tumors. Eur Radiol 13:1669–1678 8. Rau TT, Hartmann A, Dietmaier W, Schmitz J, Hohenberger W, Hofstaedter F, Katenkamp K (2008) Plexiform angiomyxoid myofibroblastic tumour: differential diagnosis of gastrointestinal stromal tumour in the stomach. J Clin Pathol 61:1136–1137 9. Wang WY, Li JN, Li GD (2010) Plexiform angiomyxoid myofibroblastic tumour of the gastric fundus: successful diagnosis and treatment by endoscopy. J Clin Pathol 63:569–570
