Cotyledonoid hydropic intravenous leiomyomatosis: a new variant leiomyoma

AIMS: We present the histopathological findings of a series of six cases of a benign uterine smooth muscle tumour with an unusual growth pattern. METHODS AND RESULTS: All cases have the appearances of the recently described dissecting (cotyledonoid) leiomyoma. In addition, three of these lesions demonstrate the features of intravenous leiomyomatosis with varying degrees of hydropic degeneration. CONCLUSIONS: This combination of phenotypes has not previously been described within the literature; therefore we propose that these are classified as examples of 'cotyledonoid hydropic intravenous leiomyomatosis', a new variant of unconventional leiomyoma.     

子宫静脉内平滑肌瘤病临床病理与生物学行为分析

目的观察和分析子宫静脉内平滑肌瘤病（intravenous leiomyomatosis of the uterus,IVL）的临床和病理学特征,期望更好地了解其生物学行为,为临床和病理诊断提供帮助。方法回顾分析29例IVL的临床和病理资料,采用LABC法免疫组化检测desmin、SMA、CD10、vimentin、CD34、ER、PR表达。结果所有患者术前均诊断为子宫平滑肌瘤或子宫腺肌病,无1例怀疑为静脉内平滑肌瘤病。手术中,29例均行冷冻切片检查且均正确诊断为子宫静脉内平滑肌瘤病;所有病例术后经石蜡包埋病理切片检查确诊。28例全子宫切除标本中,肿块均沿脉管腔穿出宫旁或浆膜下。获访的18例患者中,1例患者在肌瘤剥出术后两次复发,行全子宫＋双侧附件切除术后随访至今无复发,其余患者随访无复发。免疫组化染色显示脉管内的肿瘤细胞desmin、SMA均阳性;脉管内皮细胞CD34阳性。结论正确认识这种少见肿瘤的大体和剖面特点可减少误诊率,术中冷冻切片检查有助于提高术中诊断率和正确选择处理方式;由于肿瘤有潜在的复发性,患者术后长期随访十分必要。     

Cutaneous clear cell neoplasms: a systematic review

Neoplasms of the skin with clear cell morphology consist of a broad variety of primary and metastatic lesions with epithelial, mesenchymal and melanocytic differentiation. The clear cell changes are attributable to a variety of causes from artifact to accumulation of intracellular substances such as glycogen, mucin, and/or lipids. The clear cell morphology is easily identified by the pathologist, however is it not specific. Additional salient histologic findings may be subtle and therefore ancillary studies such as immunohistochemistry and molecular studies may be necessary to help elucidate a diagnosis. This review features cutaneous neoplasms characterized by clear cell changes, organized by histogenesis. It discusses the differential diagnosis of these lesions with a focus on helpful immunohistochemical and molecular studies which may aid in the clinicopathologic evaluation of these challenging lesions.     

Intravenous leiomyomatosis of the uterus with multiple pulmonary metastases associated with large bullae-like cyst formation

We present a case of uterine intravenous leiomyomatosis associated with multiple pulmonary metastases with bullae-like cystic change. A 53-year-old woman who had undergone hysterectomy 5 years previously underwent an operation for multiple pulmonary nodules with bullae formation. After resection of several large bullae, a subsequent extirpation of the pulmonary nodules was performed, and a pathological examination showed multiple leiomyomatous nodules with occasional cystic change. A review of the previous slides of the uterus and immunohistochemical analysis of the proliferating ability using anti-Ki-67 and anti-proliferating cell nuclear antigen (PCNA) antibodies were performed. Proliferating cells of the uterus had very few mitotic figures for their high cellularity, and the labeling indices of Ki-67 and PCNA indicated very low levels in both uterine neoplasm and pulmonary nodules. From these findings, an intravenous leiomyomatosis associated with multiple pulmonary metastases was diagnosed.     

Perivascular epithelioid cell tumor (PEComa) of soft tissue: case report with ultrastructural study

A perivascular epithelioid cell tumor (PEComa) arising in the abdominal wall of a 44-year-old female is described. The lesion was a well-circumscribed but unencapsulated, rubbery, subcutaneous mass measuring 3.5 x 3.5 x 3.0 cm which was removed by simple excision. It was characterized by a nest- or sheet-like arrangement of round to polygonal cells with round nuclei and abundant clear to slightly eosinophilic cytoplasm containing glycogen. There was mild to moderate nuclear pleomorphism with mitotic activity of 6 per 10 high power fields. A short fascicular proliferation of the tumor cells was observed focally. The stroma contained abundant small vascular channels with hyalinization. Immunohistochemically, the tumor cells were strongly positive for vimentin, epithelial membrane antigen, alpha-smooth muscle actin, and HMB45. Ultrastructural examination showed poorly differentiated mesenchymal tumor cells without premelanosomes. There was local recurrence 6 years after excision. Pathologists and clinicians should be aware of the existence of PEComa in soft tissue and should differentiate it from other similar lesions.     

Metastatizing low-grade clear cell leiomyosarcoma of the uterus

An unusual case of uterine clear cell tumor is reported In a 56-year-old woman. The neoplasm was Identified as a peculiar low-grade leiomyosarcoma, composed mainly of watery, clear large cells with round, fairly regular nuclei. No appreciable pleomorphlsm or high mitotlc activity was noted. There was no necrosis. The presence of occasional areas of transition between these cells and typical spindle leiomyosarcoma cells, together with the immunohisto-chemical results, allowed the recognition of a smooth muscle origin of this clear cell tumor. The patient was treated by hysterectomy. Six years later she developed an Inguinal metastasis resembling an hibernoma, and then later developed a large retroperitoneal metastasis, which was composed entirely of clear cells and was distinguished from a Ilposarcoma by Immunohlstochemlstry.     

Intravenous leiomyomatosis of the uterus: A clinicopathologic analysis of 13 cases with an emphasis on histogenesis

The object of this study is to investigate the prognosis and potential histologic origin of uterine intravenous leiomyomatosis (IVL). We retrospectively analyzed the clinicopathologic and immunohistochemical features of 13 cases of IVL from a single institute. The patients underwent hysterectomy (3 with bilateral salpingo-oophorectomy, and 8 with excision of the broad ligaments and/or parametrium). They survived with no evidence of disease for 6–90 months. Intravascular worm-like plugs were macroscopically identified in the myometrium in 10 of 13 cases (76.9%). Six patients (46.1%) had extra-uterine involvement. Histopathologically, the intravascular tumor foci were covered with endothelium. We found the presence of congested vessels in the tumor and the surrounding myometrium in 9 of 13 cases (69.2%). The concurrent entities included seven uterine leiomyomas, one leiomyoma with adenomyosis, one adenomyosis, and one pulmonary benign metastasizing leiomyoma. Estrogen receptor and desmin were positive in IVL, and negative in the vascular wall. We conclude that IVL confined to the uterus may have a favorable prognosis, and we believe IVL is likely to originate from contiguous leiomyoma or myometrium.     

Diffuse leiomyomatosis of the uterus

The clinical and pathological features of four cases of the rare entity diffuse leiomyomatosis of the uterus are described. The patients, who ranged in age from 28 to 35 years, presented with a six month to ten year history of abnormal uterine bleeding, dysmenorrhoea and an enlarged uterus. Hysterectomy in each case revealed a symmetrically enlarged uterus containing numerous small ill-defined leiomyomatous nodules. On microscopic examination the nodules were composed of compact fascicles and interweaving bundles of plump uniform benign smooth muscle cells. The nodules blended with each other and merged imperceptibly with the surrounding less cellular normal myometrium. The four patients are alive and well without further treatment. The follow-up period ranged from six months to twelve years.     

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

Neoplasms with perivascular epithelioid cell differentiation (PEComas) of the pancreas are rare, and only 22 cases have been reported globally. Therefore, clinician and pathologist knowledge of this tumor’s biologic behavior and molecular genetics has been limited. A 40-year-old female patient presented with a space-occupying mass in the pancreas found by abdominal B-mode ultrasonography upon physical examination. Laparoscopic resection of the pancreatic body and tail was performed, and a cystic-solid tumor of about 2 × 2 cm was identified. PEComa is a type of mesenchymal tumor with uncertain biologic behavior, more frequently found in females. PEComa features a unique histomorphology and immunophenotype. We summarize the characteristics and research progress of the pancreatic PEComa, which will be convenient for physicians and pathologists to fully understand the disease to avoid misdiagnosis and to provide a reference for treatment and prognosis.     

Cytologic findings of a clear cell parathyroid lesion

On fine‐needle aspiration (FNA) biopsy, clear cell parathyroid lesions can be misdiagnosed as thyroid neoplasms, salivary gland neoplasms, paraganglioma, or even metastatic renal cell carcinoma. We report the clinicopathological, cytologic, and histologic findings of a clear cell parathyroid tumor in a 64‐year‐old HIV‐positive patient. A computed tomography (CT) scan with contrast showed a heterogeneous and enhancing mass at the inferolateral aspect of the left thyroid lobe. FNA showed a cellular smear with many single and loosely clustered tumor cells with finely granular and vacuolated light‐purple cytoplasm and central nuclei. Occasional microfollicular structures were noted. No colloid was seen. This FNA was misdiagnosed as a follicular neoplasm of the thyroid. Sections of the excised mass showed large polyhedral cells with well‐defined cell membranes and clear cytoplasm with a small amount of eosinophilic granular material. These clear cells were positive for pancytokeratin and PTH immunohistochemical stains. These results favored a diagnosis of parathyroid Water Clear Cell Adenoma. This brief report highlights the cytologic findings of clear cell parathyroid lesions and their potential diagnostic pitfalls. Diagn. Cytopathol. 2013;41:725–728. © 2013 Wiley Periodicals, Inc.     

Sclerosing variant of perivascular epithelioid cell tumor in the female genital organs

Perivascular epithelioid cell tumor (PEComas), other than angiomyolipoma, clear cell 'sugar' tumor of the lung, and lymphangioleiomyomatosis, is an uncommon mesenchymal neoplasm that arises in the soft tissue and visceral organs. We report herein two cases of sclerosing PEComa; a distinctive variant of PEComa, which is characterized by extensive stromal hyalinization, occurring in the uterus and broad ligament. The patients were 34- and 51-year-old females with no family history of tuberous sclerosis complex. Macroscopically, the tumors had white to gray cut surfaces and were microscopically composed of predominantly spindle- to polygon-shaped cells with clear to slightly eosinophilic cytoplasm and pleomorphic nuclei focally arranged in a perivascular pattern, accompanied by marked stromal hyalinization. These tumor cells were immunohistochemically positive for HMB45 and α-smooth muscle actin. Although this variant of PEComa is very rare, this entity should be considered as a potential primary neoplasm of the female genital organs.     

子宫绒毛叶状水泡状静脉内平滑肌瘤病一例

患者女,37岁。体检发现盆腔肿块2d,于2006年2月6日入院。体检:子宫如孕2个月大小,形态规则,表面光整。盆腔左侧6cm×5cm大小肿物,质中,活动度欠佳,与子宫分界欠清。超声检查:子宫前位、偏大,宫后壁肌层增厚,回声不均匀,内膜线前移。左附件区见一53mm×47mm×35mm大小的混合性回声团块,正常左卵巢未显示,右侧卵巢未见超声异常,考虑左侧卵巢畸胎瘤、子宫腺肌症可能。拟施腹腔镜下卵巢瘤剥除术。术中镜下见子宫增大如孕2个月,子宫左后壁见一约5cm×5cm大小囊性结节状肿块,两侧附件正常,无腹水,实施腹腔镜辅助下阴式全子宫切除术。临床初步诊断…     

Perivascular epithelioid cell tumor (PEComa) of the pancreas: Immunoelectron microscopy and review of the literature

A perivascular epithelioid tumor (PEComa) is a rare tumor probably arising from the perivascular epithelioid cells. Only three cases of pancreatic PEComa have been reported in the English-language literature. The present report describes an extremely rare case of pancreatic PEComa. A 47-year-old Japanese woman complained of lower abdominal pain and a well-demarcated solid tumor was found in the pancreatic head. There was no history of tuberous sclerosis complexes. Pylorus-preserving pancreaticoduodenectomy was thus performed. There was a well-demarcated, solid tumor measuring 17 mm in the pancreatic head. The tumor was composed of a diffuse proliferation of epithelioid tumor cells with many blood vessels but no adipose tissue. The tumor cells expressed HMB45 and α-smooth muscle actin. Ultrastructurally, the tumor cells possessed many membrane-bound granules that were positive for HMB45 on immunoelectron microscopy. The results of immunoelectron microscopy show that some PEComas possess not only typical melanosomes or premelanosomes but also aberrant melanosomes.     

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.     

Glycogen-rich clear cell carcinoma of the breast: a solid variant with mucus. A light microscopic, immunohistochemical and ultrastructural study of a case

The light microscopic, immunohistochemical and ultrastructural features of a clear cell carcinoma of the breast have been studied. Both intraductal and invasive components were found. Histochemistry showed large amounts of intracytoplasmic glycogen and sparse neutral mucin in the tumour. The tumour cells were stained by antisera to carcinoembryonic antigen, keratin and epithelial membrane antigen, but not by antisera to alpha-lactalbumin, desmin or vimentin. Ultrastructurally, the epithelial derivation of the tumour was confirmed. Only a few intracytoplasmic lumina were demonstrated. The tumour was classified as a mucin-containing variant of glycogen-rich, clear cell carcinoma of the breast.     

Perivascular epithelioid cell tumor of the uterus: a case report

A case of a perivascular epithelioid cell tumor (PEComa) arising in the uterus of a 35-year-old woman is presented. Imaging studies revealed a 5 cm well circumscribed mass in the uterine fundus. The tumor was composed of clear to faintly eosinophilic, epithelioid and spindled cells. Immunohistochemically, most tumour cells were strongly positive for HMB-45, smooth muscle actin and desmine, but negative for epithelial markers, S-100 Protein and neuroendocrine markers. Reevaluation of the patient for signs of tuberous sclerosis complex after the diagnosis gave negative results. At the most recent follow-up 4 months later there was no evidence of recurrence.     

Comparative genomic hybridization study of perivascular epithelioid cell tumor: molecular genetic evidence of perivascular epithelioid cell tumor as a distinctive neoplasm

Perivascular epithelioid cell tumor (PEComa) is a neoplasm composed chiefly of HMB-45-positive epithelioid cells with clear to granular cytoplasm and a perivascular distribution. Such tumors have been reported in different organs under a variety of designations. The cytogenetic features of these neoplasms have not been well studied. We collected 9 tumors (5 of kidney, 1 of prostate, 1 of urinary bladder, 1 of the pelvic cavity soft tissue, and 1 of uterus) from 8 patients, including one patient with tuberous sclerosis complex. The paraffin blocks of tumor tissue were submitted for comparative genomic hybridization analyses. Gross chromosomal aberrances were observed in all cases. The frequent imbalances were losses on chromosome 19 (8 cases), 16p (6 cases), 17p (6 cases), 1p (5 cases), and 18p (4 cases) and gains on chromosome X (6 cases), 12q (6 cases), 3q (5 cases), 5 (4 cases), and 2q (4 cases). The frequent deletion of 16p in which TSC2 gene is located indicates the oncogenetic relationship of PEComas with angiomyolipoma as a TSC2-linked neoplasm. From a molecular genetic perspective, the recurrent chromosomal alterations in both renal and extrarenal tumors further support the concept of PEComa as a distinctive tumor entity regardless of anatomic location.