Alveolar Soft Part Sarcoma: A Case Report with Immunohistochemical Study Koji YAMAGUCHI,1,2Junichi SOEJ~Ma,2'3 Shogo MAEDAt a n d Katsutoshi KITAMURA1 ABSTRACT: We report herein, a rare case o f a 28 year old J a p a n e s e man with alveolar soft part sarcoma. T h e patient noticed a rapidly growing mass in the inner aspect of his left thigh and a smooth-surfaced, h a r d nodule revealing bruit o n auscultation was f o u n d on physical examination. An angiogram showed dense neovascularity from the left p r o f u n d a femoris artery. Histopathologically, the tumor was composed of nests o f tumor cells with hyperchromatic nuclei and vesicular cytoplasm arranged in an alveolar fashion a n d a histopathologic diagnosis of alveolar soft part sarcoma was made. Immunohistochemically, the t u m o r cells had desmin and vimentin immunoreactants in the cytoplasm, suggesting muscle origin. KEY WORDS:
alveolar soft part sarcoma, immunohistochemistry
A l v e o l a r soft part sarcoma (ASPS) is an u n c o m m o n soft tissue neoplasm. 1-~ It is a clinically a n d morphologically distinct soft tissue sarcoma first defined a n d n a m e d by Christopherson et al. in 1952. 4 T h e incidence o f this t u m o r ranges f r o m 0.4 p e r cent to 1 per cent of all soft tissue sarcomas 1,5 and a surgeon may scarcely experience one case during his profession. T h e histogenesis is still uncertain although Smetana and Scott 6 p r o p o s e d that it was an unusual variant o f paraganglioma. Different authors have suggested neuroectodermal or neural origin while others favor a myogenic origin. We
1The Department of Surgery, Shinkokura Hospital, Kitakyushu, Japan 2The First Department of Surgery, Faculty of Medicine, Kyushu University, Fukuoka, Japan 3The Department of Surgery, Kyushu Welfare Pension Hospital, Kitakyushu, Japan Reprint requests to: Koji Yamaguchi, MD, The First Department of Surgery, Faculty of Medicine, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812, Japan
report herein a typical case of ASPS experienced in a 28 year old J a p a n e s e man and present the results of immunohistochemistry done in an attempt to ascertain the origin of this rare tumor. ~ASE REPORT
A 28 year old J a p a n e s e m a n noticed a mass in the i n n e r aspect of his left thigh one m o n t h prior to admission, measuring 2 cm in its greates t diameter. T h e mass rapidly increased in size and the patient experienced neither pain n o r functional disturbance. On admission to Shinkokura Hospital, the tumor was 10 cm in its greatest diameter and located in the subcutaneous tissue of the inner aspect of the left thigh. T h e r e was no redness, local heat, pain or tenderness but the tumor h a d pulsation a n d bruit on auscultation. An angiogram demonstrated man}, t u m o r vessels f r o m the left p r o f u n d a femoris artery in the arterial p h a s e a n d no tumor staining in the venous phase. The patient underwent extirpation of the tumor which revealed it to b e located mainly in the
JAPANESEJOURNALOF SURGERY,VOL. 20, No. 4 pp. 476-480, 1990
Volume 20 Number 4
Alveolar soft part sarcoma
subcutaneous tissue and partially invading the muscle tissue. T h e margin was welldefined and the tumor easily dissected from the surrounding tissue. T h e surgical specimen was a smooth-surfaced and hard tumor, measuring 11 X 9 X 8 cm and weighing 118 g. The cut-surface exhibited yellowish-white solid tissue with necrotic loci (Fig. 1). Microscopically, the tumor was composed of nests of tumor cells forming alveolar structures (Fig. 2). T h e tumor cells were polygonal and had centrally placed hyperchromatic nuclei with prominent nucleoli and vesicular cytoplasm (Fig. 3). Mitosis was scarcely seen and at the periphery, the tumor invaded the
Fig. 1. Cut-surface of the tumor yields yellow-white soft and friable tissue with necrosis.
Fig. 2. Organoid or nest-like arrangement of tumor cells (HE, X73).
Fig. 3. Nests of large tumor cells with central loss of cellular cohesion resulting in a pseudoalveolar pattern. The cell nests are separated by thin-walled sinusoidal vascular spaces lined with flattened endothelial cells (HE, X160).
Fig. 4. Venous invasion of tumor cells at the periphery of the main tumor (HE, X39). adjacent striated muscle and permeated the vascular spaces (Fig. 4). Periodic acid Schiff (PAS) stain showed a granular PAS positive substance in the cytoplasm and failed to reveal typical crystalline materials. A histopathologic diagnosis of alveolar soft part sarcoma was made. An immunohistochemical study was done with the antibodies listed in Table 1, using the avidin-biotin complex peroxidase method (ABC method). Cytokeratin and epithelial m e m b r a n e antigen (EMA) were the epithelial markers, v i m e n t i n a
Yamaguchi et al.
JPn)uJy Surg. 1990
Fig. 5. The tumor cells are immunoreactive to desmin (ABC method, X100).
= X X X X X X X X X X 9
mesenchymal marker, desmin, actin and myoglobin myogenic markers, and neuron specific enolase (NSE) and S-100 protein neurogenic markers. The tumor cells were positive for vimentin and desmin and negative for EMA, carcinoembryonic antigen (CEA), Factor VIII (F VIII) related antigen, NSE and actin. The immunoreactants of vimentin and desmin were diffusely present in the cytoplasm of the tumor cells (Fig. 5). Ten days after the operation, a chest X-ray film showed bilateral multiple coin lesions in the lung fields and although the patient was given chemotherapy using vincristine, he died of local recurrence and distant metastases about 10 m o n t h s after his initial operation.
b~ O ..=
v ~- .~