Breast mass due to alveolar soft part sarcoma of the pectoris major muscle

Pectoralis major muscle sarcoma masquerading breast lesion: A rare case report with review of literature

Pectoralis major muscle sarcomas are extremely rare and can mimic breast lesion clinically. We report a case of poorly differentiated sarcoma of the pectoralis major muscle in a 63-year-old woman of south east Asian ethnicity presenting with a progressively increasing right breast lump. Mammography, ultrasonography (US), contrast-enhanced computed tomography, and biopsy were done to make the final diagnosis. Complete surgical excision was planned but deferred due to pulmonary metastasis, and the patient was treated with palliative chemotherapy. Clinical examination may be confusing but radiological and pathological investigations provide detailed information about the location and the extent of the disease and a definitive tissue diagnosis can only be made on histopathology which will be helpful in preoperative planning and further treatment of the patient.

Sonographic imaging features of alveolar soft part sarcoma: Case series and literature review

BACKGROUND

Alveolar soft part sarcoma (ASPS) is a rare tumor but potentially fatal condition. Understanding the imaging and clinical features of ASPS is of certain value for preoperative qualitative diagnosis and clinical treatment of tumors. Nevertheless, there have been only 11 documented case reports describing the sonographic features in the English literature.

METHODS

Three patients with confirmed ASPS occurring primarily in the limbs were enrolled in this study. Complete surgical excision was performed with conservative limb function. We pay particular attention to the ultrasonographic features and performed a literature review of ASPS cases.

RESULTS

With regular surveillance, one patient had no symptom recurrence and two developed lung and/or breast metastasis later. The specific sonographic findings were heterogeneous hypoechoic, well-circumscribed, and lobulated or round contours on grayscale images, abundant flow signals of intratumoral and extratumoral tubular structures on color Doppler images.

CONCLUSION SUBSECTIONS

Its low incidence rate and lack of characteristic clinical manifestations often result in misdiagnosis of ASPS. The specific sonographic findings may add useful diagnostic information.

Primary Alveolar Soft Part Sarcoma (ASPS) of the Breast

Alveolar soft part sarcoma (ASPS) is a rare neoplasm that most commonly presents in the lower extremities. Although ASPS has distinctive histologic features, it may cause diagnostic problems when it arises in unusual locations. To our knowledge, only 1 case of ASPS arising within the breast has previously been reported. Here, we report a second case of primary mammary ASPS. The patient was a 44-year-old woman who presented with a breast mass. Needle biopsy was performed, yielding a polygonal cell lesion with abundant, predominantly xanthomatous cytoplasm. The cells labeled strongly for the histiocytic marker CD68, suggesting a benign macrophage-rich lesion. However, the unusual nature of the lesion as well as the prominence of nucleoli prompted suggestion for an excision. The excision more clearly revealed the lesion's alveolar architecture and demonstrated cells with more eosinophilic cytoplasm, along with the xanthomatous cells. The diagnosis of ASPS was confirmed by electron microscopy, which revealed characteristic membranebound rhomboidal crystals, as well as by nuclear labeling for TFE3 protein by immunohistochemistry. With this report, we confirm the utility of a novel immunohistochmical technique for the identification of an ASPS presenting in an unusual locale.

Primary alveolar soft part sarcoma of uterine corpus: a case report with immunohistochemical, ultrastructural study and review of literature

Background

Alveolar soft part sarcoma (ASPS) is a rare mesenchymal malignancy. ASPS usually occurs most commonly in the deep soft tissues of the thigh and buttock or the head and neck regions.

ASPS that originate from the uterine corpus are even more rare, with only 10 previous cases reported in the English literature.

Case presentation

In our case, the alveolar features were completely lost and the tumour shows a solid, non-alveolar pattern and the nuclei have marked variation in nuclear size, and multinucleation. The correct pathological diagnosis has been made by immuno- histochemical and ultrastructural features, which rvealed overexpression of TFE3 and peculiar cytoplasmic crystalline inclusions.

In this paper, an additional case of primary ASPS of uterine corpus is reported with immunohistochemical, ultrastructural study and review of literature in the effort to delineate its clinical and pathological features. In this unusual site, the diagnosis can be problematic because ASPS can mimic other primary or metastatic uterine neoplasms.

Conclusions

Thus, in this unusual presentation an essential diagnostic marker is the nuclear over-expression of TFE3 as well as ultrastructural study, which reveals the presence of peculiar cytoplasmic crystalline inclusions.

Primary alveolar soft part sarcoma of vertebra: a case report and literature review

Alveolar soft part sarcoma (ASPS) is a rare malignant soft tissue tumor, which rarely occurs in bone. We present a case of ASPS in a 23-year-old man with a 2-month history of back pain. Computed tomography scanning and magnetic resonance images demonstrated a destructive process in the 12th thoracic vertebra associated with a unilateral soft tissue mass. The tumor showed evidence of hypervascularity on MRI; it obviously was enhanced on T1-weighted images after injection of Gd-GDPA, and signal voids were shown on all pulse sequences which may help to differentiate ASPS from other tumors of the vertebra. We believe that this is the first case of ASPS arising in a vertebra.

A proposed explanation for female predominance in alveolar soft part sarcoma

BACKGROUND

Alveolar soft-part sarcoma (ASPS) is a rare malignant soft tissue tumor with both clinically and morphologically distinct features. It often involves the extremities of adolescents and young adults and shows a predilection for females. Recently, ASPS was found to have a nonreciprocal der(17)t(X;17) translocation with the corresponding fusion gene located in chromosome 17. Because females have an extra X-chromosome, their likelihood of developing an X;autosome translocation is theoretically double that of males, and thus, this extra X-chromosome is a likely explanation for female predominance of ASPS.

METHODS

The authors used data from the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) registry program, which included 87 ASPS cases (33 males and 54 females), and published ASPS cases, which included 317 cases (121 males and 196 females), to test our hypothesis. The authors compared the observed proportion of female cases with that expected under the two X-chromosomes-double-risk hypothesis including the consideration of X-inactivation status.

RESULTS

The hypothesis that the fusion gene is not subject to X-inactivation is supported by data (P = 0.6, 0.24, and 0.20 for SEER cases, published cases, and their combination, respectively). In contrast, the competing hypothesis that the fusion gene is subject to X-inactivation is rejected (P = 0.007, < 0.00001, and < 0.00001 for SEER cases, published cases, and their combination, respectively).

CONCLUSIONS

Therefore, the authors found a statistical association between the female predominance observed in ASPS and female possession of an extra X-chromosome/noninactivation of the ASPS X;autosome translocation fusion gene.

Alveolar soft part sarcoma: the role of prognostic markers

Alveolar soft part sarcoma (ASPS) is a rare malignant neoplasm characterized by slow growth and indolent behavior. The role of proliferative markers and tumor suppressor genes is unknown in these tumors. To investigate their potential role in diagnosis and prognosis, we studied 13 cases of primary ASPS and 14 metastases and correlated them with clinicopathologic parameters. Immunohistochemistry was performed with anti-p53 and anti-Ki-67 antibodies. Polymerase chain reaction after tumor microdissection was performed to search for possible loss of heterozygosity in chromosomes 1p, 9p, 17q, 22q, and TP53 to identify possible changes that may clarify the histogenesis of these tumors. Four of five (80%) primary ASPS cases were positive for Ki-67 and all of them developed later metastases. One patient whose tumor did not stain for Ki-67 remained free of disease for 9 years. Eleven of 13 (85%) metastases were positive for Ki-67; however, there was no correlation with final outcome. All the primary ASPS cases analyzed for p53 yielded negative results, but two (15%) of 13 metastases were weakly positive. There was no correlation of these markers with prognosis or clinicopathologic parameters. No loss of heterozygosity was found except in one of nine (11%) informative metastases for D1S165 (at 1p36). Our preliminary data suggest that Ki-67-positive immunostaining may be a prognostic indicator for the development of metastases in ASPS.