Perivascular epithelioid cell neoplasm of the colon

Pediatric case of colonic perivascular epithelioid cell tumor complicated with intussusception and anal incarceration: A case report

BACKGROUND

Perivascular epithelioid cell tumor (PEComa) represents a group of rare mesenchymal tumors. PEComa can occur in many organs but is rare in the colorectum, especially in children. Furthermore, PEComa is a rare cause of intussusception, the telescoping of a segment of the gastrointestinal tract into an adjacent one. We describe a rare case of pediatric PEComa complicated with intussusception and anal incarceration, and conduct a review of the current literature.

CASE SUMMARY

A 12-year-old girl presented with abdominal pain and abdominal ultrasound suggested intussusception. Endoscopic direct-vision intussusception treatment and colonoscopy was performed. A spherical tumor was discovered in the transverse colon and removed by surgery. Postoperative pathologic analyses revealed that the tumor volume was 5.0 cm × 4.5 cm × 3.0 cm and the tumor tissue was located in the submucosa of the colon, arranged in an alveolar pattern. The cell morphology was regular, no neoplastic necrosis was observed, and nuclear fission was rare. The immunohistochemical staining results were as follows: Human melanoma black 45 (HMB 45) (+), cluster of differentiation 31 (CD31) (+), cytokeratin (-), melanoma-associated antigen recognized by T cells (-), smooth muscle actin (-), molleya (-), desmin (-), S-100 (-), CD117 (-), and Ki67 (positive rate in hot spot < 5%). Combined with the results of pathology and immunohistochemistry, we diagnosed the tumor as PEComa. Postoperative recovery was good at the 4 mo follow-up.

CONCLUSION

The diagnosis of PEComa mainly depends on pathology and immunohistochemistry. Radical resection is the preferred treatment method.

A Liver Transplant for Local Control in a Pediatric Patient with Metastatic TFE3-Associated Perivascular Epithelioid Cell Tumor (PEComa) to the Liver

Perivascular epithelioid cell tumors (PEComas) are rare mesenchymal tumors with widespread distribution throughout the body and unpredictable clinical behavior. Recently, a subset of these tumors has been reported to harbor Transcription Factor E3 (TFE3) gene rearrangement with distinct morphologic and immunophenotypic features. Although limited, these tumors may represent a separate entity from the conventional PEComas and may require different treatment approaches. Surgery is the main treatment option with no clear consensus on systemic therapy. Here, we present the first case of a malignant pediatric colonic TFE3-associated PEComa with isolated liver metastasis leading to liver transplantation for the local control.

Unusual paediatric sigmoid perivascular epithelioid cell tumour with regional lymph node metastasis treated using gemcitabine and docetaxel: a case report and literature review

Perivascular epithelioid cell tumour (PEComa) is an extremely rare neoplasm with distinctive morphology and specific expression of immunohistochemical markers. The lesion is typically diagnosed in middle-aged women, with few reports of paediatric cases, and there is no standardized treatment for the tumour type. Here, the case of a 17-year-old female, who presented with painless haematochezia for 2 days and was diagnosed with gastrointestinal PEComa of the sigmoid colon with regional lymph node metastasis after serial examination, is presented. She was treated by surgical resection of the tumour and cytotoxic chemotherapy comprising 900 mg/m² gemcitabine and 100 mg/m² docetaxel every 3 weeks for six cycles. Haematochezia did not recur, and complete response was achieved, with progression-free survival at the 24-month follow-up examination. Surgical resection with adjuvant conventional cytotoxic chemotherapy may be considered as an option for treating gastrointestinal PEComa.

Successful management of perivascular epithelioid cell tumor of the rectum with recurrent liver metastases: A case report

RATIONALE

The perivascular epithelioid cell tumor (PEComa) is rare in young man and rarely occurs in the large intestine.

PATIENT CONCERNS

The clinical characteristics, diagnosis, and managements in a 28-year-old boy who presented with sudden onset of cramping and abdominal pain and intermittent melena with a blood pressure of 74/39 mm Hg was retrospectively reviewed. CT scan of the abdomen revealed a 8.9 × 7.2 cm mass in the pelvic floor.

DIAGNOSES

Given the difficulty of obtaining a diagnostic specimen, surgical resection was performed. The pathology report of lower anterior resection was malignant PEComa of the rectum in 2006.

INTERVENTIONS

Treatment consisted of surgical resection only without additional adjuvant therapy. Over the next 49 months (until 2010) after surgery, abdominal CT showed a 0.6-cm hypodense mass over the liver with suspected liver metastasis. He refused any further evaluation and treatment. After 4 years (2014), abdominal CT showed that the original mass had increased from 0.6 to 1.5 cm and the number of tumors had increased from 1 to 3. In August 2014, he underwent a metastatic hepatectomy without additional chemotherapy or radiotherapy.

OUTCOMES

We noted that the metastatic progression was slow in the 4 years after the first operation. At 28 months after metastatic hepatectomy, the patient was doing well. There was also no recurrence of the PEComa of the rectum at the 120-month follow-up in 2016.

LESSONS

To the best of our knowledge, this is the first report of a PEComa of the rectum with liver metastases treated with only surgical resection. At approximately 8.8 cm, this is the largest PEComa of the rectum reported in the recent literature.

A systematic review: perivascular epithelioid cell tumor of gastrointestinal tract

Perivascular epithelioid cell tumor (PEComa) is a rare entity with distinctive morphology and of expressing myomelanocytic markers. Gastrointestinal tract (GI) is one of the most common anatomic sites of origin and counts for 20% to 25% of all reported cases of perivascular epithelioid cell tumors not otherwise specified (PEComas-NOS). However, the biologic behavior of perivascular epithelioid cell tumors of gastrointestinal tract (GI PEComas-NOS) is still unclear. The aim of conducting this systematic review is to sum up what is known so far of the epidemiology, natural history, management and prognosis of GI PEComas-NOS.A systematic research was performed on PubMed and EMBASE using the following terms: ("perivascular epithelioid cell tumor" or "PEComa") and ("gastrointestinal tract" or "GI" or "oral " or "mouth" or "esophagus" or "gullet" or "gastric" or "stomach" or "duodenum" or "jejunum" or "ileum" or "cecum" or "colon" or "colorectal" or "sigmoid" or "rectum" or "anus" or "mesentery") up to December 1, 2015. Retrieved GI PEComas-NOS publications, which included these terms, contains case reports, case series to case characteristic researches.A total of 168 articles were reviewed, 41 GI PEComa-NOS English studies among which were retrieved for analysis. We reviewed epidemiology, natural history, management and prognosis of GI PEComa-NOS. Generally GI PEComa-NOS is believed to have women predomination. The most frequently involved location is colon with non-specific clinical signs. Pathologically, GI PEComas-NOS shows epithelioid predominance (70%), meanwhile coexpresses melanocytic and muscle markers characteristically, while immunohistochemistry is a useful tool for identify, which indicates that HMB-45 is regarded as the most sensitive reagent. Complete resection served as mainstay of treatment, while chemotherapy should be unanimously considered to apply in malignant cases. Eventually, it is necessary for closed and long-term follow-up with endoscope and imaging for ruling out local recurrence or distant metastasis of this tumor.GI PEComas-NOS lives with unclear behavior. There are still many unverified clinicopathological issues of GI PEComas-NOS that needs to be clarified. Further studies and analyses concerning this rare entity should be brought out. Thus, the randomized clinical researches (RCTs) are required to be conducted.

Perivascular epithelioid cell tumor in the duodenum: challenge in differential diagnosis

Defined as a family of scarce mesenchymal neoplasm which distinctively co-express melanocytic markers and muscle markers, perivascular epithelioid cell tumors (PEComas) have been reported almost everybody site. Perivascular epithelioid cell tumors-not otherwise specified (PEComas-NOS) arising in the gastrointestinal (GI) tract are still restricted into sporadic case reports. Herein we present a case of GI PEComas-NOS which occurs in the duodenum of a 27-year-old male. Our initial diagnosis tended to gastrointestinal stromal tumor or smooth muscle tumor till the correct diagnosis of perivascular epithelioid cell tumor (PEComa) was established by postoperative pathological examination. We also make a literature review of GI PEComas-NOS and highlight the challenge it brings to the differential diagnosis.

Perivascular epithelioid cell tumor of gastrointestinal tract: case report and review of the literature

Perivascular epithelioid cell tumors of gastrointestinal tract (GI PEComas) are exceedingly rare, with only a limited number of published reports worldwide. Given the scarcity of GI PEComas and their relatively short follow-up periods, our current knowledge of their biologic behavior, molecular genetic alterations, diagnostic criteria, and prognostic factors continues to be very limited.We present 2 cases of GI PEComas, one of which showed an aggressive histologic behavior that underwent multiple combined chemotherapies. We also review the available English-language medical literature on GI PEComas-not otherwise specified (PEComas-NOS) and discuss their clinicopathological and molecular genetic features.Pathologic analyses including histomorphologic, immunohistochemical, and ultrastructural studies were performed to evaluate the clinicopathological features of GI PEComas, their diagnosis, and differential diagnosis. Immunohistochemistry, semiquantitative reverse transcriptase polymerase chain reaction, and DNA sequencing assays were carried out to detect the potential molecular genetic alterations in our cases. Microscopically, the tumors showed distinctive histologic features of PEComas-NOS, including fascicular or nested architecture, epithelioid or spindled cell type, and clear to eosinophilic cytoplasm. The tumor cells were immunohistochemically positive for melanocytic markers. Molecular pathological assays confirmed a PSF-TFE3 gene fusion in one of our cases. Furthermore, in this case microphthalmia-associated transcription factor and its downstream genes were found to exhibit elevated transcript levels.Knowledge about the molecular genetic alterations in GI PEComas is still limited and warrants further study.

Perivascular epithelioid cell tumor of the rectum: report of a case and review of the literature

We report a case of perivascular epithelioid cell tumor arising in the rectum of a 55-year-old woman. The tumor was treated by transanal endoscopic microsurgery. After 1 year follow-up, the patient is alive with no radiologic or endoscopic evidence of recurrence. Perivascular epithelioid cell tumor is a rare mesenchymal tumor characterized by co-expression of melanocytic and smooth muscle markers. This rare tumor can arise in various organs, including the falciform ligament, uterus, uterine cervix, liver, kidney, lung, breast, cardiac septum, pancreas, prostate, thigh, and gastrointestinal tract. Perivascular epithelioid cell tumor of the gastrointestinal tract is very rare, with only 23 previously reported cases. We review the literature on perivascular epithelioid cell tumors arising in the gastrointestinal tract.

Malignant perivascular epithelioid cell tumor of the retroperitoneum

Perivascular epithelioid cell tumors (PEComas) are a rare type of mesenchymal neoplasms characterized by a proliferation of perivascular cells with an epithelioid phenotype and expression of myo-melanocytic markers. The majority of PEComas seem to be benign and usually their prognosis is good. Malignant cases are extremely rare, exhibiting a malignant course with local recurrences and distant metastases. We herein report a case of a malignant PEComa arising in the retroperitoneum. The patient was a 55-year-old woman experiencing abdominal discomfort for approximately one month. Ultrasound and computer tomography (CT) scans of the abdomen revealed a solid mass arising from the retroperitoneum. Microscopically, the tumor was composed of epithelioid cells mixed with spindled cells. The nucleus had significant atypia, and the mitoses were obvious. The focal intravascular tumor embolus was visible. Immunohistochemically, the epithelioid tumor cells were positive for HMB45 and Melan-A, and the spindled tumor celLs were positive for SMA and desmin. Seven months after a surgical resection, an ultrasound revealed liver metastases. In conclusion, the malignant PEComas of the retroperitoneum is a very rare neoplasm with unique morphological and immunohistochemical characteristics. It should be differentiated from other epithelioid cell tumors of the retroperitoneum.

Mesenchymal Tumors of the Gastrointestinal Tract Other than GIST

Mesenchymal tumors involve the gastrointestinal (GI) tract more frequently than other visceral organs. Many such tumors are small, and are benign and increasingly being detected incidentally during colonoscopic screening. Some tumors show distinctive features at this site, such as schwannoma and clear cell sarcoma-like tumor of the GI tract. Without knowledge of these features, recognition of these tumor types can be difficult. This reviews addresses recent developments and diagnostic features of mesenchymal tumors of the GI tract other than gastrointestinal stromal tumor (GIST).

Primary perivascular epithelioid cell tumor in the rectum: a case report and review of the literature

Perivascular epithelioid cell tumor (PEComa) is a rare collection of tumors arising in a wide array of anatomic locations. It is characterized by the presence of a peculiar population of myomelanocytic marker-positive perivascular epithelioid cells, and is commonly detected in the uterus. The colorectal area is an uncommon site for primary PEComa. In this study, we describe a 17-year-old patient presenting with a rectal polyp. Histologically, the tumor consisted of sheets of round to polygonal epithelioid cells with clear and granular cytoplasm, and a prominent capillary network. Some of the tumor cells were positive for Fontana-Masson staining. Immunohistochemically, the tumor cells were positive for HMB-45, and were negative for cytokeratin, vimentin, S-100 protein, actin, desmin, EMA, CD34, and c-kit. After finding melanosomes or premelanosomes at the ultrastructural level, the diagnosis of PEComa was made. Although PEComa arising within the intestinal tract is unusual and clinically unexpected, PEComa should be considered in the differential diagnosis of rectal polypoid lesions.

Perivascular epithelioid cell tumor of male pelvic cavity: a case report and literature review

Perivascular epithelioid cell tumors (PEComas) are a family of rare mesenchymal neoplasms. The PEComas, composed of epithelioid and spindle cells, have the same cellular and immunohistochemical features but are found in different visceral and soft tissue sites. Here, we report the histological and immunohistochemical features of one case of PEComa restricted in the pelvic visceral peritoneum of a male patient. The patient was treated with radical surgery, and was well and on follow-up visits without tumor recurrence.

Malignant perivascular epithelioid cell tumor of the esophagus

Malignant perivascular epithelioid cell tumor (PEComa) is a rare tumor composed of hybrid tumor cells characterized by immunoreactivity for both melanocytic and smooth muscle markers. This paper describes the uncommon esophageal location of an 8 cm PEComa in a 75-year-old Caucasian man who was presented with ingravescent dysphagia. Although PEComas arising within the gastrointestinal tract are exceptional findings, clinicians should not exclude this class of tumors in the diagnostic investigation of a bulky lesion of the esophageal wall.