Fine-needle aspiration cytology of prostatic embryonal rhabdomyosarcoma: a case report

Fine-needle aspiration of the prostate has recently gained popularity as a reliable technique in the evaluation of prostatic nodules for malignancy. The cytologic features of adenocarcinoma have been described, but the features of other more unusual tumors have not been widely publicized. We report a case of embryonal rhabdomyosarcoma of the prostate gland with epithelioid cytologic features.     

梭形细胞横纹肌肉瘤3例临床病理学分析及文献复习

目的探讨梭形细胞横纹肌肉瘤(spindle cell rhabdomyosarcoma,SCRM)的临床病理学特征、诊断及鉴别诊断。方法回顾性分析3例SCRM的临床表现、组织学与免疫表型特征,并复习相关文献。结果 3例均为男性婴幼儿,年龄2天~4岁。肿瘤部位:睾丸旁2例,腰背部1例,肿瘤直径2~6 cm;眼观:肿瘤边界清,无包膜,切面灰白色,质地韧。镜检:肿瘤呈侵袭性生长,边界尚清。瘤细胞由束状排列的梭形细胞组成,胞质深嗜伊红色,纤维状,可呈席纹状或漩涡状排列,局部区域可见波浪状结构,似神经纤维。部分细胞内可见横纹结构,有些区域见散在的横纹肌母细胞。瘤细胞间质内有少量胶原纤维。细胞核多为长圆形,有些细胞核呈纤细波浪状,细胞核异型不明显,核分裂象偶见。免疫表型:vimentin、desmin、myogenin和Myo D1均阳性,CK、α-inhabin、AFP、CD34、S-100蛋白均阴性。结论 SCRM是横纹肌肉瘤中一种少见的新类型,常发生于婴幼儿。需与婴儿纤维瘤病、先天性纤维肉瘤、纤维肉瘤、平滑肌肉瘤、恶性蝾螈瘤及促纤维组织的恶性黑色素瘤相鉴别。     

Primary embryonal spindle cell cardiac rhabdomyosarcoma: Case report

Primary cardiac tumors are rare. Of all primary heart neoplasms, sarcomas account for around 10%, and of these, rhabdomyosarcomas (RMS) constitute a minority. A case of primary left atrial RMS, reminiscent of leiomyosarcoma, is reported herein. Histologically, the tumor was composed of tightly-packed spindle-shaped cells arranged in long fascicles. At immunohistochemistry, the tumor cells stained strongly and diffusely with vimentin, muscle-specific actin, desmin and myogenin, and focally with fast-myosin and sarcomeric actin. WT-1 showed diffuse and intense cytoplasmic staining. Staining for calponin was weak. Staining for alpha-SMA, H-caldesmon, CD34, epithelial membrane antigen (EMA), keratin wide-spectrum (CK w.s.), and S100 protein was negative. Electron microscopy revealed poorly differentiated spindle cells, containing contractile filaments with a “Z-band-like” appearance. The final diagnosis was embryonal RMS, spindle cell variant. Conclusively, spindle cell RMS is a well-recognized variant of embryonal RMS, typically occurring in soft tissue, with only rare cases described in visceral organs. This is the first case of primary cardiac spindle cell RMS ever described.     

Pleural effusion cytology of embryonal rhabdomyosarcoma

This case report concerns an embryonal rhabdomyosarcoma of the testis in a 31-yr-old white male patient who underwent radical left orchiectomy, followed by combined irradiation and chemotherapy, and who 2 yr later presented with dyspnea at rest, nonproductive cough, and lower back pain for 1 wk. Chest radiographs demonstrated a bilateral pleural effusion and diffuse infiltrating lesion of the pleurae, mimicking a mesothelioma. The pleural fluid displayed noncohesive, malignant, small, round cells about 2–5 times larger than mature lymphocyes. They had large, darkly staining, pleomorphic nuclei and bubbly cytoplasm with poorly defined borders. The diagnosis of embryonal rhabdomyosarcoma was supported by a positive myosin immunostaining and ultrastructural findings of intracytoplasmic actin and myosin-type microfilaments. Our case is also notable in that the tumor was a pure rhabdomyosarcoma involving a testicular origin, and the patient is the oldest reported in the literature. Diagn. Cytopathol. 16:270–273, 1997. © 1997 Wiley-Liss, Inc.     

A spindle cell tumour in the bladder

Spindle cell lesions in the bladder can be challenging and present a wide differential diagnosis. We report a case of one of these diagnoses - sarcomatoid variant of urothelial carcinoma. We also describe how to differentiate between benign and malignant mimics and discuss the molecular features of sarcomatoid variant of urothelial carcinoma.     

Histopathological,immunohistochemical and molecular cytogenetic analysis of 21 spindle cell/sclerosing rhabdomyosarcomas

Recently, spindle cell/sclerosing rhabdomyosarcoma (RMS) has been recognized as another distinct variant of a RMS. We evaluated clinicopathological features of 21 cases of spindle cell and sclerosing RMS and performed fluorescent in situ hybridization (FISH) testing in 10 (47.6%) tumours. Twenty‐one tumours occurred in 16 males and 5 females (mean age, 19.7 years); commonly in the head and neck region (8) (38%) and extremities (7) (33.3%), followed by paratesticular region (2) (9.5%), chest wall (1), abdomen (1), pelvis (1) and paraspinal region (1). Average tumour size was 7.9 cm. Histopathologically, tumours that were spindle cell type (8) (38%) mostly occurred in the head and neck region, while sclerosing type (10) (47.6%) mostly occurred in the extremities. Remaining three (14.2%) tumours were mixed (sclerosing with spindle cell type). Tumour areas resembling embryonal RMS (ERMS) and alveolar RMS (ARMS) were noted in eight and three tumours respectively. Immunohistochemically, tumour cells were positive for desmin (21/21) (100%), MyoD1 (19/19) (100%), myogenin (13/15) (86.6%), SMA (2/3) and MIC2 (1/8) (12.5%). On FISH testing, none of the 10 tumours exhibited RMS1 (PAX3‐FOXO1) or RMS 2 (PAX7‐FOXO1) fusion. Eighteen patients underwent surgical resection and were offered adjuvant chemotherapy (CT) (4 cases), adjuvant CT + radiotherapy (RT) (4 cases) and adjuvant RT (1 case). Two patients underwent CT and a single patient received CT + RT. On follow‐up (16 cases) (2–36 months), six tumours recurred and nine metastasized. Spindle/sclerosing RMSs are aggressive tumours and occur commonly in the head and neck and extremity sites. These tumours are histopathologically interrelated. Their immunohistochemical and cytogenetic profile is closer to ERMS than ARMS.     

成人梭形细胞横纹肌肉瘤9例临床病理学分析

目的探讨成人梭形细胞横纹肌肉瘤(spindle cell rhabdom yosarcoma,SRMS)的临床病理学特征、免疫表型和鉴别诊断。方法回顾性分析9例成人SRMS的临床资料、病理学形态和免疫组织化学标记结果。结果9例患者中7例男性,2例女性。年龄20～80岁,平均45岁。发生于头颈部4例,包括右下颌、咽部、鼻咽部和左上颌,占总数的44%。前臂、腰部、大腿、小腿、睾丸分别1例。均表现为逐渐增大的肿块。肿块直径2～14cm,平均5.9cm。组织学上主要由具有轻度非典型性的梭形细胞组成,呈交叉的束状排列,散在于梭形细胞之间有少量的梭形或多角形的横纹肌母细胞。在2例局灶区域可见明显的间质硬化,2例局灶区域可见假血管瘤样结构,1例散在少量疏松黏液样区域,在1例可见局灶区域瘤细胞呈轻度的多形性,但不见奇异核的横纹肌母细胞。免疫组织化学标记显示,梭形细胞表达vimentin、desmin、CD99和MyoD1,多数表达myogenin和MSA(分别为6例和7例),均不表达S-100、CD34、CK和HMB-45。术后随访6个月～4年,发生于睾丸患者有腹腔静脉旁转移,发生于小腿者有肝转移。4例复发,2例死亡。结论成人SRMS少见,好发于男性,头颈部是最好发部位,具有较强的侵袭性行为。形态学上应与多种梭形细胞肿瘤相鉴别。     

SYT在诊断单相纤维型滑膜肉瘤中的价值

目的 探讨SYT在单相纤维型滑膜肉瘤(monophasic fibrous synovial sarcoma,MFSS)的诊断及与其它梭形细胞肿瘤鉴别诊断中的作用.方法 收集MFSS 36例、其它梭形细胞肿瘤32例,其中包括恶性外周神经鞘膜瘤7例、纤维肉瘤6例、平滑肌肉瘤4例、恶性纤维组织细胞瘤7例和孤立性纤维性肿瘤8例,检测sYT蛋白在上述病例中的表达.结果 SYT在MFSS中的阳性表达率为91.67%(33/36),其中15例呈弥漫强阳性表达(>80%的瘤细胞核呈强阳性),12例呈不同程度的阳性表达,50%～80%的瘤细胞核呈强阳性表达.SYT在其他梭形细胞间叶肿瘤中的阳性表达率为59.37%(19/32),其中6例呈弥漫强阳性表达(>80%的瘤细胞核呈强阳性),7例呈不同程度的阳性表达,50%～80%的瘤细胞核呈强阳性.结论 SYT蛋白在MFSS和其他梭形细胞肿瘤中均有较强的阳性表达,提示SYT抗体在MFSS与其他梭形细胞肿瘤的鉴别诊断中作用有限.     

Extranodal follicular dendritic cell sarcoma of the tonsil - case report of an epithelioid cell variant with osteoclastic giant cells

Follicular dendritic cell sarcomas are rare neoplasms arising from the accessory cells of the lymph nodes, the follicular dendritic cells. They commonly occur in the lymph nodes, but have also been reported at extranodal sites (especially the tonsil). At both sites, there is usually a proliferation of spindled to ovoid cells, mimicking a mesenchymal tumor. Herein, we report a tonsillar tumor in a 50-year-old man, which was composed exclusively of large polygonal cells and numerous osteoclastic giant cells that resembled a giant cell carcinoma. The true nature of the tumor was revealed after an array of immunohistochemical stains. The patient is well 4 years after tonsillectomy.     

小细胞恶性肿瘤MyoD1、myogenin的染色敏感性和特异性

目的：研究肌源性调节蛋白在小细胞恶性肿瘤病理诊断与鉴别诊断中的作用。方法：应用免疫组化S－法，对56例小细胞恶性肿瘤，包括19例的胚胎性横纹肌肉瘤、6例的腺泡状横纹肌肉瘤、3例的Wilm瘤、14例的Wwing肉瘤／PNETs、14例的神经母细胞瘤以及4例的多形性横纹肌肉瘤行MyoD1、myogenin、MSA、desmin,myoglobin和CD99染色标记，结果：MyoD1和myogenin阳性核染色分别见于21／29（72．41％）和20／29（68．97％）的横纹肌肉瘤。除多形性横纹肌肉瘤外，4例MyoD1与5例myogenin核染色阴性者没有重叠。3例Wilm瘤中2例幼年型MyoD1核染色阳性，而myogenin只有1例核染色阳性，另1例年型Wilm瘤二者染色阴性。14例的Ewing肉瘤／PNETs的14例的神经母细胞瘤未见核阳性染色，MyoD1和myogenin核阳性染色与横纹肌肉瘤的分化程度呈负相关，在较小的原始肿瘤细胞中，MyoD1和myogenin核染色比较较高，而具有骨骼肌分化的，较大的横纹肌母细胞核阳性染色比例较低，在横纹肌肉瘤中，MyoD1阳性核染色的肿瘤细胞比myogenin多，myogenin多在小的肿瘤细胞核上染色，而MyoD1无论小的原始肿瘤细胞或是稍大的具有骨骼肌分化的肿瘤细胞均有不同程度的表达。MSA、desmin和myoglobin在小细胞肿瘤中染色的敏感性较低；结论：对于小细胞横纹肌肉瘤的诊断与鉴别诊断。MyoD1和myogenin是两种高敏感性和高度特异性的抗体，当疑为胚胎性横纹肌肉瘤或腺泡状横纹肌肉瘤时，应使用一组抗体，包括MyoD1、myogenin、MSA、desmin、myoglobin等有助于诊断。     

Evaluation of new monoclonal anti-MyoD1 and anti-myogenin antibodies for the diagnosis of rhabdomyosarcoma

New monoclonal anti-MyoD1 and anti-myogenin antibodies were evaluated immunohistochemically to determine whether they are useful in discriminating rhabdomyosarcoma (RMS) from other soft tissue tumors in routinely processed sections. Neither MyoD1 nor myogenin was expressed in normal, mature striated muscle. In RMS, nuclear expression of MyoD1 and myogenin was found in 82 and 80% of non-overlapping cases, respectively. MyoD1 was generally expressed in small, primitive tumor cells, and larger cells exhibiting morphological evidence of skeletal muscle differentiation failed to express positive nuclear immunostaining. Positive nuclear staining for myogenin was stronger than that for MyoD1 in cases with abundant differentiated tumor cells, but was less prominent in cases in which small, primitive tumor cells predominated. No leiomyosarcomas, Ewing's sarcomas/peripheral primitive neuroectodermal tumors or other soft tissue tumors exhibited nuclear expression of MyoD1 or myogenin. In conclusion, both anti-MyoD1 and anti-myogenin antibodies are useful for diagnosing RMS and for discriminating RMS from other soft tissue tumors.     

Pigmented spindle cell carcinoid tumour of the thymus with ectopic adrenocorticotropic hormone secretion: report of a rare variant and differential diagnosis of mediastinal spindle cell neoplasms

AIMS: A variety of histological variants of thymic carcinoid tumour have been described. A rare case of pigmented spindle cell carcinoid tumour of the thymus is documented and compared with the reported cases of thymic pigmented carcinoid tumour in the literature, with a discussion of the differential diagnosis of spindle cell tumours of the mediastinum. METHODS AND RESULTS: A thymic tumour with ectopic adrenocorticotropic hormone (ACTH) secretion was resected from a 24-year-old man suffering from Cushing's syndrome. Histological, immunohistochemical, and ultrastructural studies revealed an ACTH-producing spindle cell carcinoid tumour harbouring pigmented melanocytes. Among four thymic pigmented carcinoid tumours reported before, only one was similar to the present case by being also an ACTH-secreting pigmented spindle cell thymic carcinoid tumour. The clinicopathological features of this tumour distinguish it from a spindle cell thymoma, spindle cell thymic carcinoma, and other mediastinal spindle cell tumours. CONCLUSIONS: This case illustrates an extremely rare variant of thymic carcinoid tumour exhibiting a spindle cell morphology and harbouring pigmented melanocytes. Awareness of this histological variant is important in the differential diagnosis of spindle cell tumours of the mediastinum.     

Spindle‐cell rhabdomyosarcoma of the thumb: Rare site,rare tumor in a child

Spindle‐cell rhabdomyosarcoma (RMS) is a relatively recently recognized favorable variant of embryonal RMS occurring mainly in the paratesticular and head and neck regions. Cytological reports of spindle‐cell RMS have been sparse in the literature and the awareness of its cytological features is not very wide among cytopathologists. A 2‐year‐old girl was brought to clinical attention for a progressively enlarging swelling of right thumb. Imaging studies showed it to be a soft‐tissue tumor in the subcutaneous region. Fine‐needle aspiration yielded moderately cellular smears composed of small, round cells and few spindle cells with tapered cytoplasm. A cytological impression of RMS was rendered, which was later confirmed as spindle‐cell RMS on excision biopsy. Spindle‐cell RMS, a favorable prognostic variant of embryonal RMS, should be considered in the cytologic diagnosis of soft‐tissue tumors with round cell and spindle cell morphology. This is especially true for tumors occurring in hitherto unreported sites. Diagn. Cytopathol. 2016;44:1094–1097. © 2016 Wiley Periodicals, Inc.     

A case of infantile rhabdomyofibrosarcoma with immunohistochemical, electronmicroscopical, and genetic analyses

A case of infantile rhabdomyofibrosarcoma arising on the buttocks of a 15-month-old boy is reported with histological, immunohistochemical, electronmicroscopical, and cytogenetic findings. Histological examination showed a proliferation of spindle-shaped cells in a fasciculated pattern, with occasional rounded rhabdomyoblastic cells with abundant eosinophilic cytoplasm. Immunohistochemically, the tumor cells expressed desmin and MyoD1 but were only weakly positive for myoglobin. No clear rhabdomyoblastic features were observed by electronmicroscopic examination. Chromosome analysis showed a clone of 46, XY, der(2)t(2;11)(q37;q13), different from any karyotypic abnormality in the original report of this neoplasm. Loss of heterozygosity at 11p15.5, the most frequent genetic alteration in embryonal rhabdomyosarcoma, was not detected. The low degree of striated muscle differentiation and tumor localization supported the diagnosis of infantile rhabdomyofibrosarcoma rather than spindle-cell rhabdomyosarcoma in this case. The present case has been uneventful as of 25 months after surgery. The rather long recurrence-free period, which has not been reported in previous cases, may be attributable to chemotherapy-induced rhabdoid differentiation of the tumor cells.     

A case of primary testicular germ cell tumor with rhabdomyosarcoma metastases as an example of applying the FISH method to diagnostic pathology

We present the interesting case of a 38-year-old man with a primary malignant tumor of the right testis that metachronously metastasized to the urinary bladder and the stomach. Histologically, the testicular tumor was a mixed germ cell tumor composed of teratoma and embryonal carcinoma, but it also contained a sarcoma component of somatic type malignancy. Metastases showed rhabdomyoblastic differentiation histologically identical to the sarcoma component of the testicular tumor that was diagnosed as rhabdomyosarcoma. By applying fluorescence in situ hybridization (FISH) to the cytogenetic examination of cells taken from the periventricular lymph node metastases, we demonstrated a structural chromosomal aberration characteristic of testicular neoplasms, i.e. the presence of isochromosome 12p (i(12p)). Additionally, the diagnosis was supported by immunohistochemistry.     

Mucinous tubular and spindle cell carcinoma with aggressive histomorphology--a sarcomatoid variant

Mucinous tubular and spindle cell carcinoma (MTSCC) is a recently described renal epithelial tumor. The bland cytomorphology of the spindled component and low-grade behavior help in its differentiation from sarcomatoid renal carcinoma. Sarcomatoid change has been reported in most histologic variants of renal cell carcinoma apart from MTSCC. Herein we report a case of an MTSCC in a 72-year-old female patient with high-grade spindled areas resembling fibrosarcomatous and undifferentiated pleomorphic sarcoma patterns with metaplastic bone. This index case also demonstrates a high proliferation index and extensive necrosis representing the first documented case of sarcomatoid change in MTSCC.     

Clear cell rhabdomyosarcoma of the nasal cavity and paranasal sinuses

This report describes two cases of alveolar rhabdomyosarcoma of the nasal cavity with unusual histological appearances mimicking clear cell carcinoma. The closely packed tumour cells were polygonal and arranged in sheets and packets. They had an appreciable amount of clear cytoplasm due to accumulation of glycogen. The diagnosis of rhabdomyosarcoma was confirmed by positive staining for desmin and myoglobin. Rhabdomyosarcoma should be included in the differential diagnosis of nasal clear cell tumours, particularly in young adults. A correct diagnosis is important, because chemotherapy is indicated even for apparently localized disease.