Logistic regression analysis of small round cell neoplasms: A cytologic study

Abstract

The diagnosis of small round cell neoplasms (SRCN) in children is difficult by both histologic and cytologic methods. These neoplasms are unified morphologically by the scanty cytoplasm surrounding relatively round nuclei containing a primitive chromatin pattern. Further categorization is achieved histologically by the recognition of architectural differentiation and cytoplasmic features. Numerous series and case reports documenting the cytologic features of SRCN have been published in the English‐language literature, but relatively few studies have statistically analyzed the diagnostic utility of these features. Our logistic regression analysis of 59 cases of SRCN indicates that the presence of an extremely scanty cytoplasm favors the diagnosis of Ewing's sarcoma (P = 0.004), as does the positive expression of cytoplasmic vacuoles (P = 0.02). Strap or tadpole cells closely correlate with the diagnosisof rhabdomyosarcoma (P < 0.001). The positive expression of rosettes strongly supports the presence of a neuroblastoma (P < 0.001). The diagnosis of Wilms' tumor is confirmed by the expression of tubules (P < 0.001). The presence of lymphoglandular bodies strongly favors the diagnosis of lymphoma (P < 0.001). While some cytologic features are highly correlated with specific SRCN, these features are not invariably present, and definitive diagnosis may require immunohistochemical or ultrastructural analysis performed on cell block material. Diagn. Cytopathol. 1999;20:271–277. © 1999 Wiley‐Liss, Inc.

Fine‐needle aspiration of adult small‐round‐cell tumors studied with flow cytometry

“…ES/PNETs are typically highly cellular smears with many small round single cells with focal cell clustering, high nuclear-cytoplasmic ratios, scanty indistinct cytoplasm, round to oval nuclei with finely stippled nuclear chromatin, and small or absent nucleoli. 4,5,8,9,21,[33][34][35] In some cases, focal nuclear molding is present, and glycogen-laden cytoplasmic vacuoles are visible on a Diff-Quik stain. 4,5,8,9,21,[33][34][35] Lymphoglandular bodies 8,33 and ganglion-like cells are not seen.…”

“…2,4 -6 Other malignancies that are considered in the SRCT differential diagnosis include blastemal-type Wilms tumor, desmoplastic small-cell tumor of the peritoneum, small-cell variant of synovial sarcoma, small-cell osteogenic sarcoma, undifferentiated (anaplastic) hepatoblastoma, Merkel-cell carcinomas, metastatic smallcell carcinomas, and granulocytic sarcomas. [1][2][3][4][5][6][7][8][9][10][11] As several studies have reported, fine-needle aspirate (FNA) has become an important modality of diagnosis for these SRCTs. 2,5,12 The use of ancillary studies has proven to be a decisive step in FNA diagnosis.…”

“…[1][2][3][4][5][6][7][8][9][10][11] As several studies have reported, fine-needle aspirate (FNA) has become an important modality of diagnosis for these SRCTs. 2,5,12 The use of ancillary studies has proven to be a decisive step in FNA diagnosis. 2,3,13 It is well recognized that immunophenotyping of antigens to identify the tissue origin is critical in the diagnosis of SRCTs.…”

Malignant small round cell tumors

“…[33738] The presence of strap or tadpole cells is deemed to be strongly associated with rhabdomyosarcoma. [57] The finding of cells with more abundant cytoplasm, eccentrically located nuclei, and bi/multinucleated tumor cells in a background of mucosubstance helps to distinguish RMS from other small round cell tumors. [3940]…”

“…[3] As seen in several study reports, fine needle aspiration cytology (FNAC) has become an important modality of diagnosis for these tumors. [45] It yields adequate numbers of dissociated, viable cells making it ideally suitable for ancillary techniques.…”