Metastatic perivascular epithelioid cell tumor of the colon in a child

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 Rare Case of a Translocation-Associated Perivascular Epithelioid Cell Neoplasm (PEComa)

A perivascular epithelioid cell tumor (PEComa) is a rare mesenchymal neoplasm composed of perivascular epithelioid cells with distinctive histologic, immunohistochemical, and genetic features. PEComas arising from various anatomical sites have been reported, but gastrointestinal PEComas are extremely rare entities. Here, we discuss the clinical and pathological features of a gastrointestinal PEComa with a transcription factor E3 (TFE3) translocation in a 17-year old adolescent male with a clinical presentation of abdominal pain and gastrointestinal bleeding. Our case report provides insight into this rare entity as well as discusses the pathophysiological aspects of TFE3-SFPQ-associated GI PEComas and their management.

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 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.

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.

[A case of a perivascular epithelioid cell tumor mimicking colon cancer]

Perivascular epithelioid cell tumor (PEComa) is extremely rare, which originated from mesenchymal cells in the intestine, and composed of histologically and immunohistochemically distinctive perivascular epithelioid cells. We report here on a case of PEComa in the sigmoid colon. A 62-year-old woman presented with hematochzia 10 days ago. Her abdominal computed tomography scan showed a 5 cm sized intraluminal fungating heterogeneously enhanced, high density mass, which infiltrated pericolic tissue surrounding the sigmoid colon. Colonoscopy showed a purple colored polypoid mass with lobulating contour in the sigmoid colon. She underwent laparoscopic anterior resection. On the histologic examination, the tumor consisted of polygonal epithelioid cells with sheet-like growth of nests, which looked like alveolar tissues in lung. The tumor cells were strongly positive stained with human melanoma black-45 (HMB-45). Pathologic examination was compatible with PEComa. Sixteen months after surgery, she did well without tumor recurrence after surgery. We review the literatures concerning PEComa of the intestine focusing on endoscopic findings.

Cardiac Epithelioid PEComa: Report of Two Cases and Review of the Literature

Cardiac PEComa is very rare. We reported two cases of epithelioid PEComas, one in an adult and one in a 2-year-old child. Both tumors were composed of sheets of epithelioid cells with coagulation necrosis. In addition, the adult case showed marked nuclear atypia and high mitotic activity with atypical mitosis and the pediatric case showed unusual clear cell features. Immunohistochemically, both tumors were positive for HMB-45 and SMA and negative for S100 and cytokeratin. Electron microscopy was performed in the pediatric case and showed premelanosomes. The adult patient developed extensive metastasis indicating malignant behavior. Prior to the two cases, only 5 other cases of cardiac PEComa were reported and the literatures are reviewed.

Soft tissue tumors of uncertain origin

Many soft tissue tumors of childhood lack obvious differentiation toward a defined mesenchymal tissue type or have a phenotype that does not correspond to any defined normal tissue. These challenging tumors are currently regarded as neoplasms of uncertain differentiation. Nonetheless, there have been great strides in the understanding of their pathologic and genetic features and biologic underpinnings. The application of new genetic information to the pathologic diagnosis among this group of tumors is an emerging area in diagnostic pediatric pathology. This article reviews the clinicopathologic features of tumors of uncertain and/or miscellaneous origin, with an emphasis on the unique aspects of these neoplasms in children and adolescents, use of diagnostic adjuncts, and differential diagnosis.

Malignant perivascular epithelioid cell tumor in children: description of a case and review of the literature

Perivascular epithelioid cell tumors (PEComas) include different morphological entities originating from perivascular epithelioid cells. Their clinical behavior is not predictable, and there are no strict histologic criteria for malignancy, although larger tumors with infiltrative growth, hypercellularity, cellular atypia, atypical mitoses, and necrosis generally have a malignant course. Pediatric PEComas are rare, with less than 40 cases reported, mostly in children older than 5 years. We describe a case of malignant PEComa of the ligamentum teres in a 2-year-old girl, characterized by the occurrence of local relapse after primary treatment with chemotherapy and surgery and poor response to imatinib mesilate and temsirolimus used after further analyses confirmed p70S6K expression involved in the mTOR pathway. The girl was eventually treated with a debulking surgical procedure and is now alive with disease 6 years after diagnosis. Literature data of children affected by PEComas were also analyzed, trying to identify pathologic characteristics that could predict their course and therapeutic options. Histologically, they may be differentiated in 3 prognostic categories: (1) benign, lacking unfavorable morphological markers; (2) with uncertain malignant potential, carrying 1 unfavorable marker; and (3) malignant, with at least 2 unfavorable markers. In the literature, 9% of cases occurred as a second malignancy probably because of genomic instability related to treatment. Their different biology and the potential value of targeted therapies remain to be explored. The indolent evolution in our patient was similar to that reported in some other cases in the literature. In terms of treatment, the present case suggests a minor response to temsirolimus compared with the adult population.

Perivascular epithelioid cell tumor of the sigmoid colon with transcription factor E3 expression

We describe here a 62-year-old woman who presented with a perivascular epithelioid cell tumor arising in the sigmoid colon. Computed tomography revealed a 5-cm-sized intraluminal fungating mass. Histologically, the tumor consisted of plump, epithelioid cells with abundant clear-to-lightly eosinophilic cytoplasm and round nuclei, arranged in an alveolar or trabecular pattern. The tumor cells were strongly positive for HMB-45 and TFE3, but negative for vimentin, cytokeratin, smooth muscle actin, S100 protein, CD117, CD34, synaptophysin, chromogranin, CD10, hepatocyte antigen, CD1a, and desmin. The tumor cells had a high Ki-67 labeling index (up to 20%). Fluorescent in situ hybridization showed no evidence of the EWS rearrangement. Based on these histologic and immunohistochemical features, our patient was diagnosed with a perivascular epithelioid cell tumor of the sigmoid colon.

Perivascular epithelioid cell tumor (PEComa) of the ascending colon: the implication of IFN-α2b treatment

A 7-year-old boy presented with hematochezia and abdominal pain. A 3.7-cm-sized mass was identified in the ascending colon by abdominal computed tomography and colonoscopy. The patient underwent surgical resection. Pathological examination revealed a low-grade perivascular epithelioid cell tumor (PEComa). PEComa in the colon is very rare. Only a few cases have been reported so far. An effective treatment method for this rare tumor has not been established yet. The patient received adjuvant interferon-α immunotherapy for 1 year. He has been tumor-free for 26 months since the initial diagnosis. This report is the first documented case of the use of interferon-α for pediatric PEComa of the colon.

Perivascular epithelioid cell neoplasm of the colon

A 17-year-old female presented with rectal bleeding from an ulcerated sigmoid mass in 1994. Initial pathological evaluation revealed a rare clear cell neoplasm of the colon, possibly originating from kidneys, adrenals, lung or a gynecologic source as a metastatic lesion. Extensive imaging studies were negative, and over the next 15 years, she remained well with no recurrence. The original resected neoplasm was reviewed and re-classified as a perivascular epithelioid cell neoplasm (PEComa). Although the long-term natural history of PEComas requires definition, increased clinical and pathological awareness should lead to increased recognition of an apparently rare type of colonic neoplasm that likely occurs more often than is currently appreciated.

Perivascular epithelioid cell tumor of the ascending colon mesentery in a child: case report and review of the literature

Perivascular epithelioid cell tumor (PEComa) is a rare mesenchymal tumor. Perivascular epithelioid cell tumors of the gastrointestinal tract are very rare, with only about 20 previous reported cases. We present a 5.5-year-old boy with PEComa of the right colon. Treatment consisted of tumor resection only, without additional adjuvant therapy. Two years after surgery, he remains free of tumor. To the best of our knowledge, this is the youngest reported child with PEComa of the colon. We review the literature concerning PEComas in children, especially those of the gastrointestinal tract. We emphasize the importance of correct immunohistochemistry diagnosis, recommended treatment, and surveillance of this unique family of tumors.

Polypoid PEComa in the rectum of a 15-year-old girl: case report and review of PEComa in the gastrointestinal tract

PEComa of the gastrointestinal tract, composed of perivascular epithelioid cells with myomelanocytic differentiation, is rare with previous literature limited to 16 case reports. There is a marked female preponderance and approximately one-third of the cases occur in the pediatric age group. We report PEComa with lymph node involvement occurring in the rectum of a 15-year-old girl, treated by surgical resection and adjuvant chemotherapy. The patient is well at 9 months follow-up with neither radiologic nor endoscopic evidence of recurrence. We review the differential diagnosis of intestinal PEComa, which includes malignant melanoma, epithelioid gastrointestinal stromal tumors, clear cell sarcoma of soft parts, alveolar soft part sarcoma, leiomyosarcoma with HMB45 expression, and paraganglioma. Immunohistochemistry can rule out many of these morphologically similar tumors but differentiation from clear cell sarcoma may require reverse transcription-polymerase chain reaction. We discuss the determination of pathologic features indicative of malignancy in PEComa, which is complicated in the gastrointestinal tract due to the small number of cases, variability of pathologic features reported, and inconsistent reporting of outcome. All 4 tumors reporting early recurrence or progression were greater than 5 cm in size and had areas of coagulative tumor necrosis. In addition, high nuclear grade and lymphovascular invasion were seen in 2 of these 4 cases. We propose that a minimum dataset for gastrointestinal PEComa should include these features along with mitotic count, infiltrative border, and tumor stage analogous to that used in colorectal carcinoma.

Clinicopathologic analysis of 4 perivascular epithelioid cell tumors (PEComas) of the gastrointestinal tract

This study describes the clinical, histologic, and immunohistochemical features of four cases of GI PEComa. The size of the tumors ranged from 3.5 to 6.0cm in diameter, and all were located in wall of the large bowel. Microscopically, the tumors were characterized by an epithelioid arrangement of tumor cells, which had abundant clear to pale eosinophilic granular cytoplasm, vesicular nuclei and prominent nucleoli. The stroma was rich in capillaries, a sinusoidal vasculature and thick-walled blood vessels. Mitotic figures were generally rare. Immunohistochemically, the tumors were positive for Vimentin (4/4), HMB-45 (4/4), Melan-A(4/4),alpha-smooth muscle actin (4/4), and desmin (3/4). The patients have been well with no evidence of disease at 8, 15, 32 and 36 months,respectively, after the surgical operation. GI tract PEComas should be regarded as tumors of an uncertain malignant potential until long-term outcome data for a larger number of patients become available.