Neurogenic polyps of the gastrointestinal tract: a clinicopathologic review with emphasis on differential diagnosis and syndromic associations

Retroperitoneal solitary neurofibroma mimicking lymph node metastasis of colon cancer: a case report

BACKGROUND

A neurofibroma is a benign tumor that arises from Schwann cells and neurofibromas occur throughout the skin of neurofibromatosis type 1 (NF-1: Von Recklinghausen's disease) patients. A retroperitoneal solitary neurofibroma without any clinical signs of NF1 has been rarely reported. Herein, we present a case of a retroperitoneal solitary neurofibroma mimicking lymph node metastasis of colon cancer as well as a literature review.

CASE PRESENTATION

An 80-year-old woman with abdominal pain and nausea was transported and diagnosed with bowel obstruction arising from sigmoid colon cancer A colonic stent was inserted to alleviate the bowel obstruction. A computed tomography scan with contrast revealed a liver tumor in segment 3, and an enlarged lymph node around the abdominal aorta. Whole-body 18F-fluorodeoxyglucose-positron emission tomography-CT (FDG-PET-CT) examine revealed increased FDG uptake in the liver tumor and enlarged lymph node. Liver and distant lymph node metastasis were diagnosed and we made a plan for a two-stage operation of the colon cancer and the metastatic lesions because laparotomy resection was needed for the retroperitoneal lymph node. Laparoscopic sigmoid colectomy was performed first. Pathological examination showed a tubular adenocarcinoma. A laparotomy for the metastatic lesions was performed to ensure complete lymph node dissection secondly. Histopathological findings of the liver tumor showed metastasis of sigmoid colon cancer. However, the tissue regarded as the enlarged lymph node was diagnosed as a neurofibroma. No metastasis and recurrence were observed.

CONCLUSION

Although most neurofibromas are benign, malignant transformation of a neurofibroma is possible. PET-CT showed our patient had a high accumulated retroperitoneal tumor co-existing with colon cancer and liver metastasis. The treatment strategy of a solitary neurofibroma must be selected carefully considering the site of occurrence and the patient's background and aggressive resection of a tumor co-existing with another malignant tumor is needed.

Incidental Delayed Diagnosis of Isolated Diffuse Ganglioneuromatosis Caused the Death of a 6-Year-Old Boy: Case Report

Intestinal diffuse ganglioneuromatosis is a rare, benign, neoplastic condition characterized by disseminated proliferation of neural elements. It has an established association with several systemic disorders including: multiple endocrine neoplasia IIB (MEN IIB) and von Recklinghausen's disease. However, isolated GNs are very rare and sporadic. We report a case of a 6-year-old patient was referred to the emergency department due to a colon perforation during endoscopy. He then underwent sigmoidectomy and the pathologic studies revealed prominent signs of diffuse ganglioneuromatosis. Unfortunately, the patient died the day after because of the late diagnosis and treatment. Such presentation emphasizes the importance of considering diffuse ganglioneuromatosis, among other causes, in patients with intractable GI symptoms despite medical treatment.

Solitary and complicated neurofibroma of small Bowel: A case report

INTRODUCTION

Neurofibromatosis is a genetic disorder characterized by tumors and pigmentary changes on the skin, such as spots that color leans to 'White Coffee'. Neurofibromas of the gastrointestinal tract are commonly associated with neurofibromatosis type I (NF1). Although, digestive involvement can be the single manifestation of the disease and may consequently; represent the only diagnostic element.

PRESENTATION OF CASE

We report here; a case of a patient admitted to the emergency department with a bowel obstruction, for which radiological investigations revealed the presence of intussusception due to an intestinal tumor. The patient underwent a bowel resection with anastomosis, and then, after being examined histologically, the result has identified an intestinal neurofibroma without evidence of malignancy. Then and on the fourth day following the surgery, the patient was discharged with good clinical improvement.

DISCUSSION

The intestinal neurofibroma may be the first and the only manifestation of neurofibromatosis type I. Also, it's uncommon to present a neurofibroma isolated from the small bowel with an intussusception, which makes the pre-surgical diagnosis very difficult. And until now, only a few case reports of these conditions have been reported.

CONCLUSION

We report this uncommon clinical case of an isolated neurofibroma from the small bowel to raise awareness among the medical team about this exceptional pathology. Nevertheless, its risk of developing serious complications and malignant transformation led us to opt for earlier surgical treatment. Furthermore, it requires a close clinical follow-up to eliminate the neurofibromatosis type I or the multiple endocrine neoplasia type II.

RET overactivation leads to concurrent Hirschsprung disease and intestinal ganglioneuromas

Appropriately balanced RET signaling is of crucial importance during embryonic neural crest cell migration, proliferation and differentiation. RET deficiency, for example, leads to intestinal aganglionosis (Hirschsprung disease), whereas overactive RET can lead to multiple endocrine neoplasia (MEN) syndromes. Some RET mutations are associated with both intestinal aganglionosis and MEN-associated tumors. This seemingly paradoxical occurrence has led to speculation of a 'Janus mutation' in RET that causes overactivation or impairment of RET activity depending on the cellular context. Using an intestinal catenary culture system to test the effects of GDNF-mediated RET activation, we demonstrate the concurrent development of distal colonic aganglionosis and intestinal ganglioneuromas. Interestingly, the tumors induced by GDNF stimulation contain enteric neuronal progenitors capable of reconstituting an enteric nervous system when transplanted into a normal developmental environment. These results suggest that a Janus mutation may not be required to explain co-existing Hirschsprung disease and MEN-associated tumors, but rather that RET overstimulation alone is enough to cause both phenotypes. The results also suggest that reprogramming tumor cells toward non-pathological fates may represent a possible therapeutic avenue for MEN-associated neoplasms.

Isolated colonic neurofibroma, a rare tumor: A case report and review of literature

BACKGROUND

Neurofibromas are tumors comprised of peripheral nerve sheath and connective tissue components. They can occur sporadically or as part of familial syndromes such as neurofibromatosis type 1. Isolated colonic neurofibroma without systemic manifestations is a rarely reported clinical entity. Here we present a case of a 51 years old male with an isolated colonic neurofibroma seen on a screening colonoscopy.

CASE SUMMARY

Fifty-one years old male who was otherwise healthy without a significant family history of cancer underwent a screening colonoscopy and was found have a 2.3 cm × 1.4 cm lesion in the colon. Tissue biopsy revealed a spindle cell tumor. Magnetic resonance imaging of the pelvis was negative for adenopathy. He underwent an endoscopic ultrasound that showed an ill-defined avascular lesion of mixed echogenicity measuring 2.8 cm × 15.2 cm in the submucosa with no communication with muscularis mucosa or propria. Immunohistochemistry staining of the tumor was strongly positive for S100, with rare penetrating axons deep within the tumor. Tumor cells were negative for c-kit and desmin and had low Ki-67 index. These findings were consistent with a solitary colonic submucosal neurofibroma. A detailed history and physical examination did not reveal any evidence of extraintestinal neurofibromatosis. He underwent transanal surgical resection of the tumor. The patient tolerated the procedure well without any complications.

CONCLUSION

While neurofibromas have been well described in literature, an isolated colonic neurofibroma is a rare pathological entity. Malignant transformation of neurofibromas has been reported in patients with neurofibromatosis syndromes. We report a case of isolated colonic neurofibroma and highlight the importance of resection due to the increased risk of tumorigenesis.

Endoscopic Management of Ganglioneuroma in the Stomach

Ganglioneuromas are rare benign tumors of neuroblastic origin that can occur anywhere along the sympathetic chain. They are rarely found in the gastrointestinal tract and can appear as solitary polypoid lesions or diffuse as part of a familial syndrome. They are often asymptomatic but may present with nonspecific symptoms depending on their anatomic location. They have no special endoscopic appearance and are diagnosed by histology and immunohistochemistry staining. We present a case of solitary gastric ganglioneuroma treated successfully with endoscopic resection.

Duodenal gangliocytic paraganglioma: A rare cause for gastrointestinal polyp

Duodenal gangliocytic paragangliomas are rare neoplasms often arising in the duodenum in close proximity to the ampulla of Vater. These neoplasms are considered to have a benign behavior with lymph node metastases being a rare phenomenon and distant metastases even more so. Although a standardized treatment has not been determined, a margin-free tumor resection seems to be the best treatment modality. We report herein the case of a 36-year-old female who presented with abdominal pain and was found to have a polyp in the second part of duodenum which was excised endoscopically. Histopathology and immunohistochemistry revealed characteristic features of this rare tumor.

Diffuse Gastric Ganglioneuromatosis: Novel Presentation of PTEN Hamartoma Syndrome-Case Report and Review of Gastric Ganglioneuromatous Proliferations and a Novel PTEN Gene Mutation

Gastrointestinal ganglioneuromatous proliferations are rare, most often found in the colon, and are three types: polypoid ganglioneuromas, ganglioneuromatous polyposis, and diffuse ganglioneuromatosis. We present a case of diffuse ganglioneuromatosis in the posterior gastric wall in a nine-year-old female. To our knowledge, this is the first reported case of diffuse ganglioneuromatosis located in the stomach. Only six cases of gastric ganglioneuromatous proliferations have previously been reported, two in English and none were diffuse ganglioneuromatosis. A diagnosis of diffuse ganglioneuromatosis is relevant for patient care because, unlike sporadic polypoid ganglioneuromas or ganglioneuromatous polyposis, most are syndromic. Diffuse ganglioneuromatosis is commonly associated with neurofibromatosis type 1, multiple endocrine neoplasia type 2b, and Cowden Syndrome, one of the phenotypes of PTEN hamartoma tumor syndrome. The patient had the noted gastric diffuse ganglioneuromatosis, as well as other major and minor criteria for Cowden syndrome. Genetic testing revealed a novel frameshift mutation in the PTEN gene in the patient, her father, paternal aunt, and the aunt's son who is a paternal first cousin of the patient.

Distinctive crypt shape in a sessile serrated adenoma/polyp: Distribution of Ki67-, p16INK4a-, WNT5A-positive cells and intraepithelial lymphocytes

Serrated lesions in the colorectum are currently predominantly classified as hyperplastic polyps (HPs), sessile serrated adenomas/polyps (SSA/Ps), and traditional serrated adenomas (TSAs) according to their morphology. However, the histological morphology and the molecular changes in the serrated lesions are still unclear. We performed immunohistochemistry for Ki67, p16^INK4a, and WNT5A in human HPs (n=22), SSA/Ps (n=41), and TSAs (n=19). The distribution of Ki67 and p16^INK4a positive cells in TSAs was different from that in HPs and SSA/Ps. Co-expression of Ki67 and P16^INK4a was infrequent in HPs and SSA/Ps; p16^INK4a-positive cells were found in the crypt cleft and stromal WNT5A-positive stromal cells were localized near the cleft in SSA/Ps, while intraepithelial lymphocytes (IELs) in SSA/Ps were more abundant than HPs. In conclusion, our study provides evidence that HPs branch because of the increase in and patchy distribution of senescent and proliferative cells, with increased and misdistributed stromal and inflammatory cells, which might contribute to creation of L- and/or T-shaped crypts, which are of distinctive shapes in SSA/Ps. Our findings may facilitate better understanding and therapy in the serrated lesions.