Crystal-Deficient Alveolar Soft Part Sarcoma

Classically, ultrastructural examination of alveolar soft part sarcoma reveals large, dramatic, rhomboid to needlelike crystals with a characteristic substructure. In this study of four cases of alveolar soft part sarcoma, only two exhibited large crystals, which were rare. All four cases, however, exhibited round, electron-dense granules, and in the two cases without large crystals these granules rarely exhibited elongation with the characteristic substructure of alveolar soft part sarcoma that permits definitive diagnosis. Two of these cases had been previously studied at other institutions, where crystals were not identified ultrastructurally and electron microscopy was considered noncontributory. Large crystals, then, may be rare or absent in alveolar soft part sarcoma. Careful search may be necessary to find granules with the characteristic periodic substructure.     

Adenosine triphosphatase activity of crystalline inclusions in alveolar soft part sarcoma. An ultrahistochemical study of a case

A case of alveolar soft part sarcoma was studied by light and electron microscopy and by electron microscopic enzyme histochemistry of adenosine triphosphatase (ATPase) and 5'nucleotidase(5'Nase). The tumor showed distinct alveolar pattern and diastase resistant PAS positive crystalline inclusions were found in the cytoplasm. Ultrastructurally, characteristic rhomboid crystals and dense granules were observed and they were positive for Mg++- and Ca++-ATPases but negative for 5'Nase. Tumor cell membrane also showed positive activity of ATPase in addition to 5'Nase. These results would support the myogenous derivation of alveolar soft part sarcoma.     

Fine‐needle aspiration of alveolar soft part sarcoma: Histologic correlation and aberrant CD68 expression

Alveolar soft part sarcoma is a rare highly malignant neoplasm of the soft tissue and usually occurs in the lower extremities of children and young adults. We report two cases of alveolar soft part sarcoma: a 24‐year‐old Latino man with a 10‐ cm neck mass and a 56‐year‐old Latino woman with a recurring thigh mass. Fine‐needle aspiration and a core biopsy were performed on both, which was followed by tumor resection on the man. The smears displayed numerous loosely cohesive or single large cells with abundant granular cytoplasm, round nuclei, vesicular chromatin, and occasional prominent nucleoli. Periodic and Schiff (PAS)‐positive, diastase‐resistant rhomboid, or needle‐shaped crystals were present. Both tumors had diffuse and strong nuclear TFE3 expression and aberrant cytoplasmic CD68 expression. Fluorescence in situ hybridization analysis was performed in the first case, which detected a characteristic translocation t(X;17)(p11;q25). The diagnosis of alveolar soft part sarcoma was rendered in both cases. Herein, we present the cytology, histology, immunohistochemistry, and molecular findings and discuss the differential diagnosis.     

Primary alveolar soft part sarcoma of bone

AIMS: Alveolar soft part sarcoma is a distinct, rare soft tissue tumour occurring primarily within the skeletal muscles or musculofascial planes in young adults. Primary involvement of bone is extremely rare. We report on six patients with alveolar soft part sarcoma occurring primarily in bone. METHODS AND RESULTS: Thorough clinical and radiographic examinations were done to rule out any other primary site. The patients were four women and two men aged 17-35 years (mean, 24.5 years). The primary site of the tumour was the femur in three patients, the ilium in one and the fibula in two. In one of the patients with fibular involvement, the tibia was also involved by direct extension. Of the long bone lesions, three were centred in the metaphysis and one in the diaphysis. Radiographically, all of the lesions demonstrated an osteolytic pattern of bone destruction with ill-defined margins and a wide zone of transition between the lesion and adjacent normal bone. Microscopically, all tumours showed the typical histological pattern of alveolar soft part sarcoma. Diastase-resistant, periodic acid-Schiff-positive crystalline structures were identified within the cytoplasm and confirmed ultrastructurally. Immunohistochemically, a keratin stain was negative in all cases; there was positive staining for MyoD1 in the cytoplasm but not the nuclei. Distant metastasis developed in four patients; one died. CONCLUSION: Alveolar soft part sarcoma arising in bone is extraordinarily rare but should be considered in the differential diagnosis of metastatic hypernephroma in a young patient.     

Primary alveolar soft part sarcoma of the lung

Alveolar soft part sarcoma (ASPS) is a rare epithelial-like soft tissue sarcoma. The two main sites of its occurrence are the lower extremities in adults and the head and neck in children. Primary pulmonary involvement of this sarcoma, without evidence of soft tissue tumor elsewhere, is very exceptional. We present a case of primary ASPS of the lung in a 42-yr-old woman. A computed tomographic scan of the thorax demonstrated a well-circumscribed, solid tumor located in the right upper lobe. The mass was resected by right upper lobectomy. After 5 months, three metastatic lesions, involving lumbar vertebrae and occipital scalp, were found. Histologically, the tumor consisted of alveolar nests of large polygonal tumor cells, the cytoplasm of which frequently revealed periodic acid-Schiff-positive, diastase-resistant intracytoplasmic rod-like structures. On immunohistochemical staining, the tumor cells were positive only for vimentin and alpha-smooth muscle actin. Ultrastructural study using electron microscopy revealed characteristic electron-dense, rhomboid intracytoplasmic crystals.     

Alveolar soft part sarcoma: A case report with emphasis on some unusual cytological features

Alveolar soft part sarcoma is a very rare, slow growing highly angiogenic tumor with poor prognosis. Most common site in children and infants is head and neck region and in adults it most commonly occurs in extremities especially thigh. In our case study, an 8 years old female patient presented with a gradually progressive left shoulder lump. FNAC from the lesion showed cellular smears with polyhedral and spindly cells showing abundant finely vacuolated cytoplasm, nuclear pleomorphism, intranuclear pseudoinclusions, and few bare nuclei. Perivascular arrangement of cells was peculiar in addition to the presence of intracytoplasmic metachromatic PAS positive diastase resistant granules. A presumptive diagnosis of alveolar soft part sarcoma with differentials of granular cell tumor and PEComa was considered and the lesion was excised. Although the histopathological features were not characteristic (ie, showing mainly solid pattern without classic alveolar pattern), immunohistochemistry were diagnostic (negative for S 100, Desmin, Cytokeratin, EMA, and moderate to strong nuclear positivity for TFE3). Thus, the diagnosis of alveolar soft part sarcoma was established. This case is being presented for its rarity and unique cytological and histopathological features.     

儿童腺泡状软组织肉瘤13例临床病理学特征

目的探讨儿童腺泡状软组织肉瘤(alveolar soft part sarcoma,ASPS)的临床病理、分子遗传学特点、诊断及鉴别诊断。方法对北京儿童医院2009年8月至2018年11月13例儿童ASPS病例存档切片行HE染色及组织化学染色[包括过碘酸-雪夫(PAS)染色及淀粉酶消化PAS(D-PAS染色)]。采用免疫组织化学染色检测TFE3、INI1、CD68等的表达,应用荧光原位杂交(FISH)法检测TFE3基因断裂易位情况。结果13例ASPS中,男童4例,女童9例,年龄1岁2个月至13岁8个月,平均7.8岁,5岁以下4例。组织学上,11例肿瘤细胞呈腺泡状、巢状排列,2例肿瘤细胞呈实性、弥漫性生长。瘤细胞胞质嗜酸性,可见明显的空泡现象,核多形性,核仁突出,核分裂象罕见,3例可见血管浸润。免疫组织化学染色TFE3弥漫核阳性,INI1、CD68、波形蛋白阳性,MyoD1、Myogenin、细胞角蛋白、S-100蛋白等均阴性。7例PAS及D-PAS染色显示肿瘤细胞质内均可见紫红色针状或棒状结晶体。9例行FISH检测,均显示TFE3基因断裂易位。结论ASPS为儿童少见软组织肿瘤,肿瘤多位于深部肌肉内,瘤细胞排列成腺泡状或巢状,同时TFE3基因位点发生断裂易位,确定诊断需要结合临床、病理形态、免疫组织化学及基因检测综合考虑。     

Fine-needle aspiration cytology of alveolar soft-part sarcoma

Alveolar soft-part sarcoma (ASPS) is a rare soft-tissue tumor. Few cases have been reported in the aspiration cytology literature. We discuss the fine-needle aspiration (FNA) cytologic features of ASPS in four patients. The smears were characterized by single cells and clusters of cells associated with thin-walled vasculature, resulting in a distinct pseudoalveolar pattern. The cells had abundant granular cytoplasm and large round nuclei with prominent central nucleoli. Binucleated and occasional multinucleated cells were present. Numerous stripped tumor nuclei were a consistent feature. Periodic acid-Schiff (PAS)-positive diastase-resistant granules were demonstrable within the intact and fragmented cytoplasm. Electron microscopy of aspirated material identified granules and crystals with the characteristic lattice pattern. To conclude, the FNA cytologic features of ASPS are characteristic. Confirmation by special stains and electron microscopy of FNA material is possible. The differential diagnostic considerations include renal cell carcinoma, paraganglioma, granular cell tumor, clear cell sarcoma, and epithelioid sarcoma.     

4例腺泡状软组织肉瘤临床病理分析及文献复习

目的：探讨腺泡状软组织肉瘤（alveolar soft-part sarcoma,ASPS）的临床病理学特征及其鉴别诊断。方法：对4例ASPS的临床资料进行回顾性分析,对标本进行组织病理学观察及免疫组织化学（免疫组化）研究。结果：患者3例为男性,年龄分别为30,25,27岁;1例为女性,34岁。发病部位4例均位于下肢深部软组织内。镜下肿瘤细胞排列成腺泡状或实性,细胞巢间可见窦状血管分隔,肿瘤细胞胞质丰富嗜酸,胞质内可见棒状结晶体。免疫组化：4例均TFE3阳性,3例MyoD1胞质阳性。1例患者随访15年后复发伴肺转移死亡,3例患者随访6个月无瘤存活。结论：ASPS是一种罕见的恶性肿瘤,青少年多见,结合临床、病理学特征及免疫组化,可做出正确诊断。鉴别诊断需除外腺泡状横纹肌肉瘤等血窦丰富的肿瘤,TFE3是该肿瘤的特异性标志物。     

Cytologic features of alveolar soft part sarcoma: report of three cases

Alveolar soft part sarcoma (ASPS) is a rare, high-grade, epithelial-like sarcoma that shows characteristic histopathologic findings. Although a chromosomal anomaly that seems specific has been recently described, its diagnosis is based on histologic and ultrastructural features. The tumor shows no specific immunohistologic findings. Cytologic features of three cases of ASPS are presented. Preoperative fine-needle aspiration (FNA) of the primary soft tissue tumor was performed in two cases. In another two, mediastinal and pulmonary and subcutaneous metastatic lesions were aspirated. In all cases the cytologic image was identical with numerous, dissociated, large neoplastic cells with round-to-plasmocytoid morphology. Cytoplasmic fragility and granularity with abundant, atypical, naked nuclei were present. In one case, FNA material was available for ultrastructural studies. It disclosed the characteristic cytoplasmic crystalline structures. A specific cytologic diagnosis of ASPS was given in all cases. In conclusion, ASPS is a rare neoplastic entity that shows a characteristic cytologic image. When accompanied by an adequate clinical context it permits specific preoperative recognition. While immunocytologic studies are helpful to exclude other neoplasms, ultrastructure may result in an exact diagnosis.     

Alveolar soft part sarcoma of the uterus

Two patients with alveolar soft part sarcoma of the uterus are described. One of the sarcomas was a submucosal nodule of the cervix, and the second was a minuscule, incidentally discovered lesion in the corpus. Both lesions contained periodic acid-Schiff-positive, diastase-resistant cytoplasmic granules, and characteristic membrane-bound crystalline inclusion bodies were demonstrated in the cervical lesion.     

Alveolar soft part sarcoma of the tongue: report of an unusual pattern in a child.

A case of an unusual, primary alveolar soft part sarcoma of the tongue in a 3-year-old boy is presented. Alveolar soft part sarcoma is a rare malignant tumor that presents more frequently in the head and neck region of infants and children. To date, only six cases of lingual alveolar soft part sarcoma presenting in the first decade of life have been reported in the English literature. The patient has undergone surgical resection without adjuvant chemotherapy or radiation. Thus far, the patient does not manifest persistent or recurrent disease.     

Alveolar soft-part sarcomas in the skeleton (author's transl)

The rare alveolar soft-part sarcomas, tumours with well defined histological pattern but uncertain histogenesis, are up to now described only in soft tissues, especially in those of the extremities of adolescents and young adults. We can report two cases of alveolar soft-part sarcomas in the sceleton, both in the right femur of 22 years old women. The delimitation of these tumours against others with similar histological pattern may be very difficult. The occurrence of these tumours in the sceleton does not require to substitute the term alveolar soft-part sarcoma by an other one.     

ALVEOLAR SOFT PART SARCOMA, GRANULAR CELL TUMOR, AND PARAGANGLIOMA: An Immunohistochemical Comparative Study

Five cases of alveolar soft part sarcoma, 5 cases of granular cell tumor, and 6 cases of paraganglioma were Investigated immunohistochemically to examine the expression of tissue-specific intermediate filaments (cytokeratin, vimentin, desmin, and glial flbrillary acidic protein (GFAP)), actin, myoglobin, and nervous tissue markers (S-100 protein, neuron-specific enolase, and Leu-7). In alveolar soft part sarcomas, some of the tumor cells were positive for desmin, but negative for nervous tissue markers. The tumor cells of granular cell tumors were stained with anti-S-100 protein antibody, but not with antineuron-specific enolase antibody. In contrast, the tumor cells of paragang-liomas were positive for neuron-specific enolase, but not for S-100 protein except for stellate cells surrounding the tumor cell nests. This immunohisto-chemical approach was valuable for the differential diagnosis of these three tumors. Furthermore, the complete absence of cytokeratin in all of the tumor cells may be helpful in distinguishing these three tumors from metastatic carcinoma in soft tissue. The histogenesis of alveolar soft part sarcoma is a matter of controversy. The result that besides desmin actin was also demonstrated in some of the tumor cells may support the myogenic origin of this tumor. ACTA     

Alveolar soft part sarcoma, granular cell tumor, and paraganglioma. An immunohistochemical comparative study

Five cases of alveolar soft part sarcoma, 5 cases of granular cell tumor, and 6 cases of paraganglioma were investigated immunohistochemically to examine the expression of tissue-specific intermediate filaments (cytokeratin, vimentin, desmin, and glial fibrillary acidic protein (GFAP], actin, myoglobin, and nervous tissue markers (S-100 protein, neuron-specific enolase, and Leu-7). In alveolar soft part sarcomas, some of the tumor cells were positive for desmin, but negative for nervous tissue markers. The tumor cells of granular cell tumors were stained with anti-S-100 protein antibody, but not with anti-neuron-specific enolase antibody. In contrast, the tumor cells of paragangliomas were positive for neuron-specific enolase, but not for S-100 protein except for stellate cells surrounding the tumor cell nests. This immunohistochemical approach was valuable for the differential diagnosis of these three tumors. Furthermore, the complete absence of cytokeratin in all of the tumor cells may be helpful in distinguishing these three tumors from metastatic carcinoma in soft tissue. The histogenesis of alveolar soft part sarcoma is a matter of controversy. The result that besides desmin actin was also demonstrated in some of the tumor cells may support the myogenic origin of this tumor.     

Filamentous Inclusions in Acinar Cell Carcinoma of the Pancreas

Acinar cell carcinoma of the pancreas exhibits a spectrum of histologic appearances. Some tumors can be readily identified by light microscopy, but others resemble endocrine/neuroen-docrine neoplasms. Ultrastructurally, though large zymogen granules of acinar cells are usually distinctive, the zymogen granules of neoplastic acinar cells are sometimes abnormally small, overlapping in size with the granules of endocrine/neu-roendocrine neoplasms. Six cases of acinar cell carcinoma, two with a typical histologic appearance and four that resembled endocrine/neuroendocrine tumors, were studied ultrastructurally. In addition to zymogen granules and abundant rough endoplasmic reticulum, all cases of acinar cell carcinoma exhibited pleomorphic, membrane bound inclusions that contained filaments. Similar inclusions were not identified in islet cell or carcinoid tumors, and several findings indicate that the inclusions represent deranged zymogen granules. In the ultrastructural study of a pancreatic neoplasm with granules, these inclusions may provide a clue for the diagnosis of acinar cell carcinoma.     

Membrane-bound Cytoplasmic Crystals, Similar to Those in Alveolar Soft Part Sarcoma, in a Human Muscle Spindle

Membrane-bound cytoplasmic crystals were found in the intrafusal fibers of a muscle spindle from a patient with neurogenic atrophy. The crystals have a periodicity of 10 nm and an intersecting axis angle of approximately 80°. This makes the crystals similar to those described in alveolar soft part sarcoma (ASPS). Because the crystals in ASPS may not be quite as specific as previously believed, and because similar crystals have been described in various other neoplasms, the present findings should not be taken as evidence for a muscle spindle derivation for ASPS.     

Membrane-bound Cytoplasmic Crystals,Similar to Those in Alveolar Soft Part Sarcoma,in a Human Muscle Spindle

Membrane-bound cytoplasmic crystals were found in the intrafusal fibers of a muscle spindle from a patient with neurogenic atrophy. The crystals have a periodicity of 10 nm and an intersecting axis angle of approximately 80°. This makes the crystals similar to those described in alveolar soft part sarcoma (ASPS). Because the crystals in ASPS may not be quite as specific as previously believed, and because similar crystals have been described in various other neoplasms, the present findings should not be taken as evidence for a muscle spindle derivation for ASPS.