Successful management of perivascular epithelioid cell tumor of the rectum with recurrent liver metastases

Abstract

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.

Unusual Pediatric Sigmoid Perivascular Epithelioid Cell Tumor with Regional Lymph Node Metastasis Treated Using Gemcitabine and Docetaxel: A Case Report and Literature Review

“…Differentiating GI PEComa from GI stromal tumor (GIST) or other sarcoma is challenging because PEComa generally presents a biphasic GIST-compatible morphology [12]. PEComa's clinical manifestation is variable and with little discrimination, including abdominal pain, rectal bleeding, or asymptomatic [3,18].…”

“…Immunohistochemical discernment of melanocytic differentiation is the most effective approach to differentiating GI PEComa from other tumors, such as GIST, angiomyolipoma, paraganglioma, malignant melanoma, and alveolar soft part sarcoma [2]. Although the precursor or normal counterpart of PEComa remains unde ned [12], HMB-45 continues to be the most sensitive and frequent melanocytic marker in 92%-100% of reports [1,2,23]. Other potential melanocytic markers are melan-A, smooth muscle actin, and microphthalmia transcription factor, which were indicated in 23%-88%, 59%-93%, and 50%-92% of reports, respectively, as well as desmin and caldesmon [1,2,8,10,14,23].…”

“…PEComa has negative expression for chromogranin A, synaptophysin and protein S100, which can divergent from paraganglioma [2]. Diagnosis of GIST can be precluded if either perivascular concentric proliferation or representative granular cytoplasm is present [3] and <50% of GISTs are strongly CD117 positive and completely lack expressions of melanocytic markers, especially HMB-45 [12].…”

“…Because of their unpredictable histopathological manifestation, patients with aggressive PEComas have poor prognosis and do not respond well to chemotherapy [5,12,13]. The mammalian target of rapamycin (mTOR) inhibitor treatment remains controversial in patients lacking the tuberous sclerosis complex (TSC) gene mutation [5,9].…”

Remote Radiotherapy in the Treatment of Patients with Perivascular Epithelial Cell Tumors

“…В частности, в 2018 г. был опубликован случай длительного наблюдения за больным ПЭКомой прямой кишки, которому в 2006 г. было выполнено удаление первичной опухоли, а в августе 2014 г. -резекция метастазов в печени, находившихся под динамическим наблюдением с 2010 г. На момент описания случая пациент находился в ремиссии уже 28 мес [6].…”