Testicular (gonadal stromal) fibroma: case report and review of the literature

A 25-year-old man presented with complaint of a painless enlargement in his left testis. The solid, encapsulated, circumscribed and grayish-white testicular mass displayed the characteristics of testicular fibroma histologically. It was composed of acellular collagenized plaques and hypercellular areas of fibroblastic spindle cells. Immunohistochemically, the neoplastic cells were positive for vimentin and smooth muscle actin, but not for cytokeratin, S-100 protein, desmin, CD99/MIC2 (a protein expressed by Sertoli cells and granulosa cells) and CD34. Only 18 cases of testicular (gonadal stromal) fibroma composed exclusively of spindle cells have been reported to date. An additional case of fibroma, which lacks definite neoplastic sex cord elements, and its differential diagnosis from other mesenchymal lesions of testis are discussed here, together with other cases in the literature.     

Periosteal chondromyxoid fibroma: a case study using imprint cytology

Bone surface is an exceptional location for chondromyxoid fibroma. Only 14 cases of juxtacortical chondromyxoid fibroma have been reported to date and, to our knowledge, none of these cases are documented with imprint cytology. We report a case of periosteal chondromyxoid fibroma located in the distal tibial metaphysis of a 4-yr-old boy. The clinical diagnosis was metaphyseal fibrous defect. Cytologic examination revealed a mixoid matrix, with stellate and spindle-shaped cells seen singly, focus of chondroid material, and epithelioid cells. Multinucleate giant cells were not seen. The diagnosis of periosteal chondromyxoid fibroma can be made by fine-needle aspiration or imprint cytology with clinico-radiologic correlation.     

胃肠道间质瘤17例临床诊治分析

目的：探讨胃肠道间质瘤（ GIST ）的临床特点、治疗方法,以提高诊断和治疗效果。方法：回顾分析我院2007年1月～2012年10月17例胃肠道间质瘤患者的临床诊断、治疗、病理及随访。结果：GIST临床表现缺少特异性。17例GIST中,9例（52．9％）发生于胃,6例（35．3％）发生于小肠（其中1例伴肝脏转移）,1例（5．9％）发生于直肠,1例（5．9％）发生于左半结肠系膜根部。 CT检查呈现不规则软组织肿块,大部分边界完整。 GIST免疫组织化学表达CD117阳性者16例（94．1％）,CD34阳性者15例（88．2％）。2例胃间质瘤患者于术后1年死于远处转移,其余患者尚未发现明显远处转移及复发征象。结论：对于疑似GIST患者,可采用胃镜、超声胃镜、B超、CT等多种手段以明确诊断。对于确诊患者,应根据肿瘤的位置、大小等采用适合手术治疗,以降低其复发率和转移率,提高患者生存期。     

Pleomorphic hyalinizing angiectatic tumor of soft parts: ultrastructural analysis of a case with original features

Pleomorphic hyalinizing angiectatic tumor, a rare neoplasm of uncertain lineage resembling malignant fibrous histiocytoma and schwannoma, was first described in 1996 by M. E. F. Smith et al. (Am Surg Pathol. 20:21-29). To date, less than 100 cases have been reported in the international literature. It occurs in subcutaneous and intramuscular soft tissues of extremities or trunk in adults without sex predilection. All lesions are composed of sheets and fascicles of spindled and pleomorphic cells associated with clusters of thick-walled ectatic vessels surrounded by a perivascular hyaline material and inflammatory cells such as mast cells. About one-half of these neoplasms express CD34. No patient has developed metastases but occasional local recurrences are possible. This tumor of uncertain lineage is suggested to be an aggressive locally growing low-grade sarcoma. Only 3 cases were previously studied by electron microscopy and appeared to consist of primitive fibroblastic cells. The authors report histological and ultrastructural characteristics of a new case of PHAT excised from the right buttock of a 66-year-old man with the presence of ganglion-like cells, a feature that has not been previously reported, and unusual central ischemic necrosis. The features of this case are suggestive of a fibroblastic origin.     

Pleomorphic Hyalinizing Angiectatic Tumor of Soft Parts: Ultrastructural Analysis of a Case with Original Features

Pleomorphic hyalinizing angiectatic tumor, a rare neoplasm of uncertain lineage resembling malignant fibrous histiocytoma and schwannoma, was first described in 1996 by M. E. F. Smith et al. (Am Surg Pathol. 20:21–29). To date, less than 100 cases have been reported in the international literature. It occurs in subcutaneous and intramuscular soft tissues of extremities or trunk in adults without sex predilection. All lesions are composed of sheets and fascicles of spindled and pleomorphic cells associated with clusters of thick-walled ectatic vessels surrounded by a perivascular hyaline material and inflammatory cells such as mast cells. About one-half of these neoplasms express CD34. No patient has developed metastases but occasional local recurrences are possible. This tumor of uncertain lineage is suggested to be an aggressive locally growing low-grade sarcoma. Only 3 cases were previously studied by electron microscopy and appeared to consist of primitive fibroblastic cells. The authors report histological and ultrastructural characteristics of a new case of PHAT excised from the right buttock of a 66-year-old man with the presence of ganglion-like cells, a feature that has not been previously reported, and unusual central ischemic necrosis. The features of this case are suggestive of a fibroblastic origin.     

Solid pancreatic hamartoma

A case of solid pancreatic hamartoma in a 58-year-old Japanese woman is presented. She had no symptoms, and a pancreatic mass was incidentally found on screening ultrasonography 4 months before admission. The patient was not alcoholic and had no history of pancreatitis. Physical examination and laboratory data were unremarkable. Preoperative imaging demonstrated a nodule in the body of the pancreas, measuring 2.0 cm in maximum diameter, which showed marked delayed enhancement during dynamic CT. The patient underwent a distal pancreatectomy under the preoperative diagnosis of pancreatic endocrine tumor and had an uneventful postoperative course. A well-demarcated solid nodule, 1.9 cm in diameter, was evident in the body of the pancreas. Microscopically, the lesion was composed of non-neoplastic, disarranged acinar cells and ducts embedded in a sclerotic stroma with elongated spindle cells, lacking discrete islets. The stromal spindle cells were immunoreactive for CD34 and CD117. The histological diagnosis was solid hamartoma of the pancreas. There was no recurrence 5 months after surgery. Herein is reported a case of solid hamartoma of the pancreas and review of the literature. A search through the literature found only two cases of solid hamartoma of the pancreas, among the 14 cases previously reported as pancreatic hamartoma.     

Renal angiomyolipoma with epithelial cysts: a rare entity and review of literature

Renal angiomyolipoma (AML) with epithelial cysts (AMLEC) is a comparatively rare benign renal tumor that is recently recognized as a distinct entity and there are relatively few reported cases in the English-language literature. To date 19 cases of AMLEC have been reported in 2 case series and a few case reports. AMLEC has been described as a cystic variant of AML. Herein we reported an AMLEC in a 25-year-old female patient, and to the best of our knowledge this is the first case report of AMLEC in Chinese. She was incidentally found to have a kidney-occupying lesion during a routine medical examination for 1 month. CT examination demonstrated a multilocular cystic lesions arising from right-kidney lower pole. The patient underwent the partial nephrectomy. Histological examination of the tumor was composed of epithelial cysts, compact subepithelial mullerian-like stroma and muscle-predominant AML. Immunohistochemically, epithelial cysts were positive for CK but negative for ER, PR, CD10 and HMB-45; the subepithelial stroma and muscle-predominant AML were positive for ER, PR and HMB-45; the subepithelial stroma was negative for SMA, but muscle-predominant AML was positive for SMA. The final histopathological diagnosis was AMLEC.     

Classical Hodgkin lymphoma arising in the rectum

We report a case of an 81-year-old immunocompetent Mexican man who underwent an abdominal-perineal rectal resection for a mass clinically thought to be carcinoma. Histopathologic diagnosis revealed classical Hodgkin lymphoma, nodular sclerosis type, involving the rectum. The diagnosis was confirmed by immunohistochemical studies that showed that the neoplastic cells were positive for CD15 and CD30 and negative for CD45 (LCA). In situ hybridization for Epstein-Barr virus small-encoded RNA was also positive in the neoplastic cells. Hodgkin lymphoma arising in the rectum of immunocompetent patients is rare, with only 12 cases (including this one) reported in the literature. Of these, the diagnosis was confirmed by immunohistochemical studies in only two cases, and this is the first case assessed and shown to be positive for Epstein-Barr virus.     

Leukaemia of natural killer cell large granular lymphocyte type with HLA-DR-CD16-CD56bright+ phenotype.

The case is reported of a 45 year old woman with the rare leukaemia of natural killer cell large granular lymphocyte (NK/ LGL) type. Cytometric analysis of leukaemic blasts showed that they were positive for CD2, CD38, and CD56 antigens but negative for a series of antigens including CD3, CD7, CD16, and HLA-DR. Rearrangements of the beta T cell receptor, and heavy and kappa immunoglobulin genes were not detected and neither were chromosomal abnormalities. Leukaemic blasts developed NK cytotoxicity. The patient failed to respond to aggressive chemotherapy and died three months after diagnosis. The lack of expression of HLA-DR is an extraordinary characteristic of this case, as all cases of acute NK cell leukaemias described to date expressed HLA-DR. The immunophenotype observed in the NK cell leukaemic blasts may represent the counterpart of a hypothetical normal cell precursor in an early stage of ontogenic NK cell development.     

Endometrial stromal sarcoma arising in vaginaEndometrial stromal sarcoma arising in vagina

Endometrial stromal sarcoma (ESS) arising in the vagina is an extremely rare extrauterine endometrial stroma sarcoma, with only 4 cases reported in the literature up to date. Here we report a case of neoplasm originating from vagina. A 32-year-old woman complained of intermittent vaginal bleeding especially after intercourse. A mass with a diameter of 1.0 cm was found in the middle and upper segments of the right posterior vaginal wall. Biopsy showed ESS. Total abdominal hysterectomy, unilateral salpingo-oophorectomy (right) and partial vaginectomy were performed. No ESS lesion was found in endometrium. The patient received six courses of platinum-containing combination chemotherapy after surgery and was free of tumor 18 months after the diagnosis of ESS. The diagnosis of ESS relies on pathologic examination. CD10 is the most useful immunohistochemical marker for the diagnosis of this tumor. The mainstay treatment of ESS is surgery. Local excision and ovarian retaining may be considered in premenopausal women.     

Fine-needle aspiration of adult small-round-cell tumors studied with flow cytometry

Immunophenotypic study is critical for the diagnosis of adult small-round-cell tumors (SRCTs). We describe three patients with Ewing's sarcoma/primitive neuroectodermal tumor (ES/PNET) and one patient with neuroblastoma in which flow cytometry immunophenotyping (FCI) on the fine-needle aspirate (FNA) and bone marrow aspirate (BMA) demonstrated an abnormal population of cells that were CD45(-) and CD16/CD56(+). Four patients with mean age of 30 years, three male and one female, clinically suspicious for a lymphoma or SRCT are described. FNA, BMA, and biopsy specimens were obtained for routine cytologic and histologic evaluation. Fresh tissue was studied by FCI. In all cases, the cytology smears showed small cells with round nuclei, slightly irregular nuclear membranes, fine chromatin, and scant cytoplasm. FCI showed CD16/56(+) and CD45(-) neoplastic cells in all cases. In one case, 76% of these cells were CD99(+). The diagnoses of ES/PNET were confirmed by immunohistochemical, ultrastructural, and cytogenetic studies. ES/PNET in FNA and BMA can be efficiently and rapidly diagnosed by combining cytologic examination with FCI using a panel including CD45, CD16/56, and CD99.     

CD117阴性胃肠道间质瘤的临床病理及免疫组织化学研究

目的 探讨免疫组织化学在形态学典型、免疫组织化学CD117阴性胃肠道间质瘤(GIST)诊断中的意义.方法 对10例CD117阴性、形态学典型的GIST进行c-kit基因第9、11、13、17号外显子及血小板源性生长因子受体α(PDGFRA)基因第12和18号外显子的基因检测,同时所有病例均进行CD117、CD34、平滑肌肌动蛋白(SMA)、结蛋白、S-100蛋白、WT-1、DOG-1 的免疫组织化学染色(EnVision法).结果 10例中8例完成c-kit及PDGFRA基因的检测,仅1例有c-kit基因第9号外显子突变,余未发现基因突变.10例CD117阴性的病例9例CD34阳性,2例SMA局灶阳性.结蛋白和S-100蛋白均阴性.DOG1弥漫阳性者5例,1例弥漫弱阳性,2例局灶阳性,2例阴性.4例WT-1弥漫阳性,2例局灶阳性,1例有散在肿瘤细胞阳性,3例阴性.结论 对胃肠道及胃肠道外形态学典型、但CD117阴性的GIST病例,联合应用多种免疫组织化学标记有助于诊断.DOG-1和WT-1可作为补充加入到CD117阴性GIST的诊断中.

Abstract：

Objective To study the immunophenotype and c-kit or platelet derived growth factor receptor alpha(PDGFRA)gene mutations in CD117-negative gastrointestinal stromal tumors(GISTs).Methods Ten cases of GISTs with typical histologic features but no CD117 expression were retrieved from the archival of Department of Pathology,Peking Union Medical College Hospital,China.The Cages were further evaluated for the presence of c-kit exons 9.11, 13 and 17 mutations and PDGFRA exons 12 and 18mutations.DNA was extracted from the paraffin-embedded tuinor tissue.The PCR products were sequenced directly for the mutations.An immunohistochemical study for CD117,CD34,smooth muscle actin,desmin,S-100 protein.WT-1 and DOC-1 Was also performed.Results Eight of the 10 Cases had the mutation tests completed.C-kit mumfion in exon 9 Wag detected in only one case.Amongst the 10 cases studied, CD34Wag expressed in 9 cases. Smooth muscle actin was focally positive in 2 cases.None of them expressed desmin or S-100 protein.DOG-1 and WT-1 were diffusely positive in 5 and 4 Cages.respectively.In addition.DOG1 Was diffusely but weakly positive in 1 case and focally expressed in 2 cages.Three cases were focally positive for WT-1.Conclusion Pathologic diagnosis of CD117-negative GISTs can be facilitated with the application of a panel of immunohistochemical markers.including DOG-1 and WT-1.     

Non-Leydig sex-cord tumors of the testis. The place of immunohistochemistry in diagnosis and prognosis. A study of twenty cases

In 20 sex-cord tumors of the testes, we investigated immunohistochemistry as a possible method for histopathological diagnosis and evaluation of prognosis. We examined the following molecules: inhibin, CD99, cytokeratin, vimentin, MIB-1, estrogen receptors and progesterone receptors. These tumors of the testes comprised 18 Sertoli cell tumors (ScT) and two undifferentiated sex-cord tumors (USCT). Four tumors have been considered as malignant, because of metastatic spread. Inhibin was expressed by the tumor cells in 80% of sex cord tumors, without any correlation to the degree of differentiation and only in 25% of the malignant cases. Inhibin is a specific marker for sex-cord tumors of the testis and is particularly useful for the diagnosis of USCT. CD99, vimentin, keratin, progesterone and estrogen receptors were expressed in, respectively, 60%, 75%, 35%, 65% and 20% of cases; 95% expressed one of the three following markers: inhibin, CD99 or vimentin. Proliferation index MIB-1 was equal to or higher than 30% in the four malignant cases versus less than 20% in other cases. Lack of inhibin expression and a proliferation index (MIB-1) greater than 30% should be considered as a criterion in favor of malignancy.     

15例原发性胃肠外来源胃肠间质瘤的临床病理特征及预后分析并文献复习

目的　探讨原发性胃肠外来源胃肠间质瘤（extragastrointestinal stromal tumors,EGISTs）的临床病理特征及预后影响因素,并复习相关文献。 方法　回顾性收集2006年1月~2017年8月广东省人民医院收治的原发性EGISTs临床资料,并进行描述性分析。 结果　共收集到15例原发性EGISTs,所有病例经病理确诊。其中男性11例,女性4例;中位发病年龄为45岁（33~70岁）。首发症状多为腹盆腔包块或腹痛。原发部位中,有4例位于腹膜后,4例位于结肠系膜,3例位于小肠系膜,1例位于盆腔,1例位于左侧胸膜腔,1例位于胰腺被膜,1例位于小网膜囊。中位随访时间为53个月（1~102个月）。免疫组化显示,14例CD117表达阳性（14/15）,10例CD34表达阳性（10/15）,6例患者DOG-1表达阳性（6/8）。有7例患者接受基因检测,2例c-KIT基因外显子9突变,2例c-KIT基因外显子11突变,1例PDGFRa基因外显子12同义突变,2例未检测到c-KIT基因及PDGFRa基因突变。依据改良NIH（National Institutes of Health）标准进行危险度分级,5例高危病例行R0术后接受伊马替尼靶向治疗,平均生存期为67个月;高危患者中8例未行辅助靶向治疗,平均生存期为36.58个月。有8例在随访过程中出现复发转移,8例出现肿瘤相关性死亡。 结论　EGISTs发病率低,症状多为腹盆腔包块,预后差;其病理特征与常见的胃肠来源的GISTs相仿。R0手术切除是治疗首选,伊马替尼辅助治疗有利于改善预后并预防复发转移。     

Metastatic Crohn’s disease accompanying granulomatous vasculitis and lymphangitis in the vulva

Metastatic Crohn’s disease (CD) is an extremely rare extragastrointestinal manifestation of CD, and is characterized histopathologically by the presence of non-caseating granulomatous inflammation. Granulomatous vasculitis and lymphangitis have rarely been documented in metastatic CD. Herein, we report the first documented case of metastatic CD accompanied by both granulomatous vasculitis and lymphangitis in the vulva. A 35-year-old Japanese female with CD presented with multiple small nodules in her vulva. Biopsy was performed under a clinical diagnosis of genital warts. A histopathological study revealed marked lymphangiectasia in the papillary dermis. Within the dilated lymphatics, lymphocytes and aggregates of macrophages were present, which are typical features of granulomatous lymphangitis. Tiny non-caseating granulomas and granulomatous vasculitis were also observed. Accordingly, a diagnosis of metastatic CD accompanied by both granulomatous vasculitis and lymphangitis was made. The occurrence of cutaneous lesions in patients with CD is well known. Albeit extremely rare, lymphangiectasia has been reported in the vulva of CD patients that clinically mimicked viral warts, as in the present case. The diagnosis of metastatic CD in the present case was not difficult because characteristic histopathological features were present, and a clinical history of CD was available. However, a few cases of genital swelling associated with granulomatous inflammation prior to a diagnosis of gastrointestinal CD have been documented. Therefore, granulomatous vasculitis and lymphangitis in the external genitals should be considered as potential indication of metastatic CD even in cases without a history of gastrointestinal CD.     

A lethal intracranial Rosai‐Dorfman disease of the brainstem diagnosed at autopsy

Rosai‐Dorfman disease (RDD) is a benign histiocytic proliferative disorder characterized by the accumulation of histiocytes in lymph nodes and various other organs. RDD seldom involves the central nervous system, and cases of purely intracranial RDD are particularly rare. We report a case of purely intracranial RDD involving the brainstem that was diagnosed at autopsy. A 68‐year‐old woman visited our hospital because of visual disturbances and loss of energy. Magnetic resonance imaging revealed an obscure mass in the brainstem. Despite exhaustive work‐ups, the etiology of the intracranial mass remained unclear. The patient died of respiratory depression, and an autopsy was performed for pathological investigation. Macroscopically, a pink pale mass 2.5 cm in diameter was found in the brainstem, with no attachment to the dura. Histologically, it was composed of histiocytic cells with incorporation of small lymphocytes (emperipolesis). Immunohistochemical staining revealed that the cells were positive for CD68 and S100 and negative for CD1a, consistent with a diagnosis of RDD. Purely intracranial RDD is extremely rare and considered benign. To date, nine cases (including ours) have been reported. To our knowledge, this is the first case of intracranial RDD with autopsy. Although generally considered benign, RDD involving the brainstem might be lethal.     

Gastric myeloid metaplasia: a case report and review of the literature

We report a case of gastric myeloid metaplasia in an 89- year-old woman with agnogenic myeloid metaplasia. The lesions were fortuitously discovered on upper endoscopy. The antral mucosa was thickened and polypoid, and on histologic examination contained immature granulocytes, megakaryocytes, and a few erythroblasts without desmoplastic stromal reaction. The granulocytes were positive for CD15, CD68, and myeloperoxidase on immunohistochemistry, and the megakaryocytes showed positive reactivity for factor VIII. Gastric myeloid metaplasia is a very rare event, and to our knowledge only 6 cases have been reported in the literature to date. It usually occurs in patients with advanced myeloproliferative syndrome. Gastric myeloid metaplasia often has a pseudotumoral appearance, leading to digestive symptoms. Histologic diagnosis is straightforward when trilinear hematopoietic elements are identified in gastric biopsies. Immunohistochemistry with anti-factor VIII antibody can be useful to confirm the presence of megakaryocytes.     

Advanced malignant solitary fibrous tumor in pelvis responding to radiation therapy

Solitary fibrous tumor (SFT) is a rare spindle cell neoplasm that is benign in most cases. Although SFT was first recognized to arise only in the pleura, recent reports indicate that SFT can involve a wide range of anatomical sites. To date, 17 cases of pelvic SFT have been reported. Herein is reported a case of a 74-year-old woman with a giant malignant SFT in the pelvis. Along with massive invasion to adjacent organs and multiple lung metastases detected on radiography, biopsy from the tumor through the vaginal wall showed malignant looking spindle-cell neoplasm with increased cellularity, areas of necrosis, and high mitotic activity (5/10 high-power fields). Immunohistochemically, the tumor cells were diffusely and strongly positive for CD34, CD99, and bcl-2. Based on pathological features and clinical presentation, diagnosis of malignant SFT was made. The patient received systemic and the intra-arterial chemotherapy followed by whole pelvic radiation therapy (50 Gy). Initial chemotherapies failed to control the tumor. Afterwards, improvement was observed radiologically and pathologically in the 12 months' follow up after the radiation therapy. This is the first report related to therapeutic remarks on advanced malignant SFT.     

The rare mediastinal lipoma: a postmortem case report

Mediastinal lipomas are extremely rare, so there are few reported cases. We report a postmortem case of this rare intrathoracic lipoma in a 79-year old female cadaver. The gross features of the tumor and histopathological findings confirmed the diagnosis of a massive simple benign lipoma. To our knowledge, this is the first case to be reported at such an advanced age and the second postmortem case found during comprehensive review of literature.