Mutation of von Hippel-Lindau tumor suppressor gene in a sporadic endolymphatic sac tumor.

Endolymphatic sac tumor (ELST) is a low-grade adenocarcinoma of the temporal bone that is presumed to originate from the endolymphatic system. Although ELSTs are extremely rare in the general population, a significant number of studies have documented the occurrence of ELST among patients with von Hippel-Lindau (VHL) disease. Because of the rarity of the tumor, however, few cases of ELST have been analyzed for mutations of the VHL tumor suppressor gene. In this study, we reported a Japanese male patient with sporadic ELST, along with a molecular genetic analysis of the VHL gene. The light microscopic and immunohistochemical features and clinical presentations were typical of ELST. Sequencing studies of the tumor DNA disclosed a G to T substitution of nucleotide 564, which resulted in an amino acid substitution (Trp to Cys). This is the first report of the VHL gene mutation in a sporadic Japanese case of ELST.     

Endolymphatic sac tumor (aggressive papillary tumor of middle ear and temporal bone): report of two cases with analysis of the VHL gene

Endolymphatic sac tumor (Heffner tumor) (ELST) is a very rare nonmetastasizing, locally aggressive low-grade adenocarcinoma of endolymphatic sac origin, which is linked to von-Hippel-Lindau disease (VHLD). VHLD is an autosomal dominant disorder characterized by an inherited genetic abnormality of the VHL gene located on the short arm of chromosome 3 (3p26-p25). VHL gene mutations have been shown both in ELSTs associated with VHLD and in sporadic cases. Because of the rarity of ELST, only a small number of cases have been subjected to molecular genetic analysis. We have encountered two patients with ELST, one of whom presented with a medical and family history of VHLD. The second was a sporadic case, the patient having no symptoms of VHLD. The tissues obtained from Heffner tumor and cerebellar hemangioblastoma from the patient with inherited VHLD possess a point mutation in exon 1 of VHL gene. This mutation is a C to T exchange at position 194, resulting in amino acid exchange S65L. No mutation was found in any of the three exons analyzed and in the exon-intron junctions of the VHL gene in the sporadic case.     

Endolymphatic sac tumor associated with a von Hippel-Lindau disease patient: an immunohistochemical study.

The authors report a case of endolymphatic sac tumor (ELST) associated with Von Hippel-Lindau disease (VHL). A 20-year-old female VHL patient received a resection of a cerebellar hemangioblastoma 3 years ago and she had a co-existing of left petrous tumor. The petrous tumor showed a remarkable progression in 3 years and was resected subtotally. Histologically, the resected petrous tumor showed a papillary structure containing cuboidal or columnar cells with fibrous stroma and numerous microvessels and destructed temporal bone, all of which are consistent with ELST. We studied the expression of various kinds of cytokeratins (CKs) immunohistochemically and found distinct expression of CKs (CAM 5.2, 34betaE-12, CK7, CK8 and CK19), but not for CK10/13 or CK20. Vascular endothelial growth factor and neuron specific enolase showed strong immunoreactivity in the tumor cells. CD34 also had weak expression. Ki-67 antigen (MIB-1) immunoreactivity was found in focal areas, and the labeling index in the highest-density area was 48.9%. These findings suggest that vascular endothelial growth factor overexpression is an important factor for angiogenesis in ELST, much like other VHL-associated tumors, and that ELST may have a more highly aggressive component than the low-grade malignancy noted in previous reports.     

桥脑小脑角区内淋巴囊肿瘤五例临床病理分析及鉴别诊断

目的 探讨内淋巴囊肿瘤(ELST)的临床病理学特征、免疫表型及其诊断与鉴别诊断。方法 分析5例ELST的临床和病理形态学特点,以EnVision二步法用波形蛋白、角蛋白(AE1/AE3)、CK8/18、CK5/6、上皮细胞膜抗原(EMA)、胶质纤维酸性蛋白(GFAP)、S-100蛋白、突触素、癌胚抗原(CEA)、甲状腺转录因子-1（TTF-1）、血管内皮生长因子(VEGF)、D2-40、Calponin、Calretinin、Ki-67等抗体进行免疫组织化学标记,取2例尸检正常内淋巴囊及8例桥脑小脑角区脉络丛乳头状瘤做对比观察。结果 ELST患者发病年龄23 ～ 35岁,男性2例,女性3例。首发症状有耳鸣、耳痛、听力下降、耳出血及流液,2例伴有头痛。病史半年至10年,其中3例有复发。影像学检查肿物位于桥脑小脑角区,伴有岩骨骨质广泛破坏。组织学改变：肿瘤呈乳头状及腺样结构,乳头被覆瘤细胞单层排列,瘤细胞界限清楚,胞质嗜酸或透明,胞核异型性不大,居中或偏向于腔面,可见扩张的腺样结构,其内有嗜酸性的胶样物质,纤维性间质中血管丰富,小血管紧贴于上皮下,5例均有硬膜或骨质内浸润。免疫组织化学标记：5例ELST的AE1/AE3、CK8/18、CK5/6及VEGF阳性,4例EMA阳性,3例Calponin局灶阳性,2例S-100蛋白局灶阳性,2例波形蛋白阳性,1例GFAP局灶阳性,1例突触素局灶弱阳性,5例CEA、TTF-1、D2-40、Calretinin均为阴性,5例CD34血管阳性,5例Ki-67阳性指数均＜1％。8例脉络丛乳头状瘤的突触素均为阳性,7例S-100蛋白阳性,2例GFAP阳性,1例D2-40阳性,4例AE1/AE3阳性,5例CK8/18阳性,8例EMA、CK5/6及Calponin均为阴性。结论 ELST很少见,其易侵袭骨质,有复发倾向,WHO中枢神经系统肿瘤分类为低度恶性,其最应与桥脑小脑角区的脉络丛乳头状瘤进行鉴别。不同的临床影像特点、组织形态及免疫组织化学染色可以鉴别。     

Endolymphatic sac tumor (aggressive papillary tumor of middle ear and temporal bone): sine qua non radiology-pathology and the University of Texas MD Anderson Cancer Center experience

Endolymphatic sac tumor (ELST) is a rare lesion of the skull base for which the origin has recently been ascertained. The endolymphatic sac is derived from neuroectoderm and is located subjacent to the posteromedial surface of the temporal bone. Patients characteristically present with hearing loss, tinnitus, and vertigo; facial nerve paralysis occurs less commonly. An indolent clinical course and long-standing symptom history is typical. Endolymphatic sac tumors are known to occur more frequently in patients with von Hippel-Lindau disease, but this is not a prerequisite for diagnosis because sporadic occurrence is common. Morphologically, all of the ELSTs showed a papillary and glandular architecture. The papillary and glandular structures were lined by a single layer of flattened cuboidal-to-columnar cells that were variably ciliated. Surgery is the treatment of choice for small ELST. Remission may last for years, but local recurrence after surgery, likely secondary to incomplete resection, can occur. Radiotherapy has a 50% cure rate with large or residual tumors. Endolymphatic sac tumor is a rare tumor that can easily be confused with other papillary lesions on histopathologic grounds, with significant treatment implications. Precise preoperative anatomic localization and computed tomography and magnetic resonance imaging feature interpretation play a paramount role in achieving an accurate final diagnosis.     

Ovarian steroid cell tumor associated with von Hippel-Lindau syndrome: a report of two cases and literature review

Steroid cell tumor (SCT) is a rare sex cord-stromal tumor accounting for only 0.1% of ovarian tumors. Steroid cell tumor, not otherwise specified (SCT, NOS) is of uncertain lineage and is the most common among the three subtypes of SCT. Patients often present with endocrine abnormalities. Von Hippel-Lindau (VHL) syndrome is an autosomal dominant disorder resulting from inactivating gene deletions, frameshifts, and missense mutations of the VHL gene. VHL syndrome can involve multiple organs and clinically is subclassified into type 1 and type 2 based on the risk of pheochromocytoma (PCC). The association of VHL syndrome with genital tract tumors is rare, and here we report two cases of SCT, NOS in patients with VHL disease. The first case is a 19-year old female with VHL and prior resection of bilateral cerebellar hemangioblastomas. During the radiological surveillance, she was found to have multiple small enhancing foci in the cerebellar hemispheres and a stable small enhancing focus in the T6 cord with associated edema, likely reflecting a small hemangioblastoma. She had long history of irregular menses and ultrasound of pelvis found a large right ovarian mass. Cystectomy specimen showed a 6.4 cm well-circumscribed lesion with yellow cut surface. Histologic examination and immunohistochemical staining confirmed the diagnosis of SCT, NOS. The second patient is a 39-year-old female with VHL, previous surgery for retinal hemangioblastomatosis and cerebellar hemangioblastoma, history of abnormal uterine bleeding and elevated testosterone. CT of abdomen and pelvis revealed bilateral multiple cystic and solid renal lesions and a large left ovarian complex cyst. Bilateral partial nephrectomy showed multiple renal cysts and clear cell renal cell carcinomas (RCCs). Left salpingo-oophorectomy showed a 7 cm lesion with yellow-orange cut surface and features consistent with SCT, NOS. Review of the previously reported VHL SCT cases (not including the current two cases) indicated a probable link between VHL syndrome and SCT.     

Cerebrospinal fluid cytology of an endolymphatic sac tumor

Endolymphatic sac tumor (ELST) is a rare neoplasm which is seldom evaluated by cytopathology. We report the clinicopathologic course and cytologic cerebrospinal fluid (CSF) findings in a 58‐year‐old patient with brainstem lesions who originally presented with vertigo but progressed to having left 7th, 8th, 9th, and 10th cranial nerve palsies, right‐sided weakness, and occipital headaches. Cytospin of the CSF revealed large epithelioid cells similar to cells seen in a surgical resection of a brain mass three months previously. Review of the surgical specimen revealed a well‐differentiated glandular and papillary neoplasm, most consistent with an endolymphatic sac tumor. Diagn. Cytopathol. 2015;43:339–342. © 2014 Wiley Periodicals, Inc.     

Rhabdoid tumor predisposition syndrome with renal tumor 10 years after brain tumor

We report a case of rhabdoid tumor predisposition syndrome with a renal tumor developing 10 years after a brain tumor, which demonstrated an unexpectedly favorable outcome. A 2-year-old boy underwent gross total resection of a brain tumor located in the fourth ventricle, and received adjuvant chemotherapy and radiotherapy. At the age of 11 years, a renal tumor was found and nephrectomy was performed. He is currently alive without evidence of disease over 2 years without postoperative therapy. Histologically, rhabdoid cells were observed in both brain and renal tumors. Loss of SMARCB1 (also known as INI1) expression was found in the nucleus of both tumor cells. Genetic testing revealed pathogenic variants of SMARCB1 exon 5 in the renal tumor and SMARCB1 exon 9 in the brain tumor. In addition, heterozygous deletion of 22q11.21-q11.23 containing the SMARCB1 locus was shared by both tumors and this deletion was identified in normal peripheral blood. Considering the histopathological and genetic findings, our case was considered to be rhabdoid tumor predisposition syndrome with atypical teratoid/rhabdoid tumor and late-onset rhabdoid tumor of the kidney.     

Mosaicism in von Hippel–Lindau disease with severe renal manifestations

von Hippel–Lindau (VHL) disease is an inheritable multisystem tumor syndrome characterized by multiple benign and malignant tumors affecting multiple organs. VHL is the result of a germline mutation in the VHL tumor suppressor gene. Molecular genomic analysis routinely confirms the clinical diagnosis. However, the use of molecular diagnostic methods can often be insufficient for the detection of mosaic germline VHL mutations, making the diagnosis of some cases of VHL difficult. Here, we report the case of a VHL mosaic patient with bilateral renal lesions in the absence of other VHL‐associated lesions. A VHL mutation was not originally detected by routine molecular testing. Nonetheless, the detection of a heterozygous c.194C>G (p.Ser65Trp) VHL mutation in the patient's daughter prompted further genetic assessment and eventually resulted in the finding of a mosaic c.194C>G (p.Ser65Trp) VHL mutation in the patient. The mutation rate was 18.8 ± 3.84% in peripheral leukocytes. As the frequency of VHL mosaicism remains underdetermined, the possibility of a diagnosis of mosaic VHL should be considered in patients with both typical and atypical VHL‐associated manifestations.     

Warthins tumor: Cyto histological spectrum with emphasis on diagnostic difficulties

Warthins tumour is characterized by the presence of epithelial proliferation in a lymphoid stroma. It has been categorized as Sieferts types: 1‐4, depending on the proportions of the 2 components. Although FNA is fairly accurate in establishing the diagnosis, the cytologic diagnosis of this tumor has potential sources of error. This retrospective study was conducted in the Department of Pathology and Lab Medicine, of a tertiary care hospital. Cytology and surgical pathology records of past 15 years were screened. A total of 1200 FNAC cases of salivary gland lesions in the past 15 years were retrieved. 36 cases with presumptive cytodiagnosis of WT were identified and histopathological correlation was done. Histopathological correlation could be done in 24 cases. 19 out of 24 cases, were confirmed as WT. The 5 cases with discordance were analyzed for potential diagnostic pitfalls. The most common discordance was in the category of papillary proliferation with minimal lymphoid infiltrate. One case proved as oncocytoma and the other was papillary oncocyticcystadenoma. The other major pitfalls, were the interpretation of atypical squamoid cells. Their presence in a lymphoid background needs consideration of cytologic diagnosis of WT, mucoepidermoid carcinoma and metastatic squamous carcinoma. FNA showed an accuracy of 79% for WT. Cytological misinterpretation can thus occur in presence of morphology other than classical Siefert type1. An awareness of these potential pitfalls should push the need for avoiding single cytologic interpretation.     

Phyllodes tumor of the prostate with exuberant glandular hyperplasia

Reported herein is an unusual case of prostatic phyllodes tumor with exuberant glandular hyperplasia that led to misdiagnosis of adenocarcinoma. The tumor was detected in a 52-year-old man who had a 1 year history of dysuria. Adenocarcinoma of the prostate was diagnosed from a needle biopsy specimen. The patient received hormonal therapy for 6 months and underwent radical prostatectomy. Histologically, the tumor had an atypical stromal cell proliferation and elongated slit-like glands characteristic of a phyllodes tumor. The tumor was also accompanied by a florid proliferation of small acini, most of which lacked basal cells, a common manifestation of adenocarcinoma in the overall tumor area. The following features of the resected tumor were helpful for concluding that these acini were benign: lack of cytological anaplasia in spite of structural atypia, presence of scattered basal cells confirmed by immunohistochemistry (high-molecular-weight cytokeratin), and histological transition from these acini to apparently benign slit-like glands. The final diagnosis was then made as 'phyllodes tumor of the prostate with exuberant glandular hyperplasia'. Atypical stromal cells might provide a clue for the recognition of this rare tumor at initial diagnosis by needle biopsy.     

Gastric tumor of complex structure

The paper describes a case of gastric tumor comprising moderately differentiated adenocarcinoma and atypical carcinoid with metastases of both types of tumor cells in the lymph nodes. Electron microscopic and immunohistochemical studies of primary gastric tumor and lymph nodal metastases confirmed the presence of both differentiation types within one space-occupying lesion: such as goblet (mucin-producing) and neuroendocrine cells. The differentiation varied in different fields of vision with a preponderance of low-grade ultrastructural differentiation cells. Thus, electron microscopic and immunohistochemical studies of tumors not only verify their diagnosis and make a histogenetic differential diagnosis of various neoplasms, but also define the degree of their maturation.     

Endolymphatic sac tumours

This review article surveys clinical and pathological literature on endolymphatic sac tumours (ELST) and summarizes characteristics that describe the entity.
ELST are rare neuroectodermal neoplasms in the petrous bone, originating from inner ear structures. They can be encountered sporadically or in von Hippel–Lindau disease. The most prominent symptom is sensorineural deafness. Historically, nomenclature of invasive adenoid tumours in the petrous bone has been divergent, the term papillary adenocarcinoma used most frequently. Histologically, they have a follicular or papillary and adenoid pattern that can be easily confused with various other neoplastic conditions including metastatic carcinoma. It remains to be verified whether similar tumours (papillary adenocarcinomas) can originate from the middle ear. Middle ear adenomas have a similar appearance but probably originate from neural crest cells in the middle ear. ELST can express a variety of epitopes (including cytokeratin and neuro-ectodermal markers) which can be detected immunohistochemically.
In cases of von Hippel–Lindau disease the cerebello-pontine angle should be included in routine radiological examinations to detect ELST before the tumours lead to deafness. In apparently sporadic cases of ELST, genetic testing for von Hippel–Lindau disease should be considered. Correct distinction of ELST from metastatic carcinoma prevents futile searches for unknown primary tumours.     

Clear cell carcinoma of the ovary simulating a yolk sac tumor

Clear cell carcinoma (CCC) of the ovary is uncommon. In young patients, this tumor may simulate a yolk sac tumor. In this case, the morphologic distinction between these tumors is often difficult but the immunohistochemical staining for CA125 and alpha foeto protein (AFP) and the response to chemotherapy are particularly helpful to resolve this problem of differential diagnosis. We report a case of a 17 year old patient who was operated for a tumor of the right ovary. The diagnosis of a yolk sac tumor was first suggested. However, because of the non response to chemotherapy, a second laparotomy was performed; the definitive pathologic examination concluded to the diagnosis of a CCC of the ovary. The young age and the immunohistochemical staining for AFP are unusual and misleading features for a CCC. Our objective about this particular case is to discuss the anatomoclinical aspects of the CCC of the ovary and to prove the role of immunohistochemistry in the differential diagnosis.     

Ovarian yolk sac tumor associated with endometrioid carcinoma and mucinous cystadenoma of the ovary

The clinicopathologic and immunohistochemical findings of an unusual case of ovarian yolk sac tumor associated with endometrioid carcinoma and mucinous cystadenoma of the ovary are reported. The tumor was detected in a 51-year-old postmenopausal woman who presented with abdominal swelling and a pelvic mass. The patient underwent total abdominal hysterectomy with bilateral salpingo-oophorectomy and omentectomy. The tumor was confined to the right ovary and measured 16.0 cm in greatest dimension. Microscopic examination revealed that the tumor had a yolk sac component associated with an endometrioid carcinoma, grade I, and a mucinous cystadenoma. A background of atypical endometriosis was noted. Immunoperoxidase studies showed that the yolk sac component stained diffusely with a cytokeratin cocktail and was focally positive for alpha-fetoprotein. It was negative for keratin 7. In contrast, the endometrioid carcinoma stained positive for keratin 7 in addition to the cytokeratin cocktail, but was negative for alpha-fetoprotein. After surgery, the patient received three cycles of chemotherapy. However, the disease progressed and the patient died 10 months after the diagnosis of the ovarian tumor.     

Sporadic endolymphatic sac tumor – a diagnostic and therapeutic challenge

Endolymphatic sac tumor (ELST) is a rare low-grade locally aggressive neoplasm of the inner ear that may occur sporadically or in the setting of von Hippel-Lindau syndrome. We herein present a case of sporadic ELST in a 39-year-old man, treated using an interdisciplinary approach (surgery + radiotherapy), with a 10-year follow-up. The patient presented with hearing loss of sudden onset. The treatment of choice for ELST is radical tumor resection, which is associated with a good long-term prognosis. Remission may last for years, but there may be local recurrences, probably as a result of incomplete resection. Adjuvant radiotherapy is an option in case of recurrence and could be discussed after incomplete resection. The purpose of this report is to call attention to ELSTs, which are difficult to diagnose due to their rarity and variety of presentations.     

Yolk sac tumor of vagina: a case report

Malignant germ-cell tumors (MGCT) are rare tumors of childhood accounting for less than 3% of pediatric malignancies. Yolk sac (endodermal sinus) tumor is one of the malignant germ cell tumor that usually involves the gonads (ovaries and testes). Its occurrence in the vagina is extremely rare. We report a 6-months old girl presented with a vaginal mass diagnosed as a yolk sac tumor. This diagnosis is confirmed by histopathologic examination, immunehistochemical studies as well as elevated serum alpha fetoprotein (AFP).     

A case of Lambert-Eaton myasthenic syndrome associated with atypical bronchopulmonary carcinoid tumor

The Lambert-Eaton myasthenic syndrome (LEMS) is typically recognized as a paraneoplastic syndrome associated with a small cell lung carcinoma (SCLC), whereas LEMS with other neuroendocrine lung tumors, including carcinoids or large cell lung carcinoma, are highly unusual. Here, we report a rare case of LEMS with atypical bronchopulmonary carcinoid tumor: a 65-yr-old man presented with progressive leg weakness and a diagnosis of LEMS was made by serial repetitive nerve stimulation test. Chest CT revealed a lung nodule with enlargement of paratracheal lymph nodes, and surgically resected lesion showed pathological features of atypical carcinoid tumor. We concluded that LEMS could be associated with rare pulmonary neuroendocrine tumor other than SCLC, which necessitates pathologic confirmation followed by aggressive treatment for optimal management in these rare cases.     

FNA diagnosis of giant cell fibroblastoma: A case report of an unusual pediatric soft tissue tumor

Giant cell fibroblastoma (GCF) is a rare pediatric soft tissue tumor, which exists on a spectrum with dermatofibrosarcoma protuberans (DFSP). Histologic features are well established for these entities; however, cytologic findings have not been well characterized. We report for the first time a case of GCF, confirmed by cytogenetics, with mixed DFSP features. In this case of an 8‐month‐old boy, a fine needle aspiration specimen showed a low‐grade spindle cell tumor, with oval to spindled cells dispersed singly and in patternless groups, and with occasional giant cells. Subsequent histologic features were consistent with GCF, which is an uncommon, CD34 positive, soft tissue neoplasm with a distinct molecular aberration. This case emphasizes the differential diagnosis in pediatric soft tissue tumors and stresses the unique features of GCF. Diagn. Cytopathol. 2015;43:325–328. © 2014 Wiley Periodicals, Inc.