Crystals of alveolar soft part sarcoma in a fine needle aspiration biopsy cytology smear. A case report.

[D.ap]

Machhi J, et al. Acta Cytol. 2002 Sep-O

Abstract
BACKGROUND: Alveolar soft part sarcoma (ASPS) is a rare soft tissue tumor. It has characteristic histomorphology, with typical ultrastructural features demonstrating unique crystalloids. It occurs predominantly in adolescents and young adults, in whom the most common location is within the fascial planes of skeletal muscle of the lower extremity.

CASE: We present fine needle aspiration biopsy (FNAB) findings along with histopathologic features and ultrastructural appearance of a large gluteal mass in a 29-year-old female. FNAB cytology smears showed single and small groups of polyhedral malignant cells with granular cytoplasm, anisokaryosis and prominent nucleoli. The delicate cytoplasm had a tendency to rupture, with the presence of many bare nuclei. The characteristic crystals were observed in Papanicolaou-stained smears within the cytoplasm and in the background near the tumor cells. This consolidated the radiologic suspicion of ASPS and facilitated the application of relevant ancillary tests. Biopsy of the mass showed the characteristic histologic pattern. Electron microscopy confirmed the diagnosis with demonstration of membrane-bound, rhomboid crystalloids with a latticelike ultrastructure.

CONCLUSION: Detection of characteristic crystalloids in Papanicolaou-stained FNAB smears facilitated a proper evaluation and correct diagnosis of ASPS.

https://www.ncbi.nlm.nih.gov/m/pubmed/12365228/

[Olga]

ASPS is a very rare but surprisingly well researched sarcoma. It just simply heartbreaking that we see so many cases when the initial resection is not done properly because the biopsy was not done, or without taking the Dx into consideration when the treatment is planned. Some locations warrant the attempt to downsize the tumor first and to make the clean surgery after, when it hopefully gets smaller and easier to resect without the functional damage...especially in new era of the immune checkpoint inhibitors and/or precise radiosurgery techniques that can be given adjutant before the primary surgery.