Cytohistologic correlations of 24 malignant peripheral nerve sheath tumor (MPNST) in 17 patients: The Institut Curie experience

Abstract

Cytomorphological patterns of malignant peripheral nerve sheath tumor (MPNST) are insufficiently documented in the literature. Cytological and histological specimens in 24 tumors in 17 patients were correlated. The review of the original cytology reports showed that four (16.6%) tumors were correctly diagnosed, eight (33.3%) were diagnosed as sarcoma not otherwise specified, four (16.7%) as fibrosarcoma, three (12.5%) as synovial sarcoma, three (12.5%) as leiomyosarcoma, and one (4.2%) case each as malignant fibrous histiocytoma and rhabdomyosarcoma. At the review tumors were histologically reclassified as well-differentiated MPNST in 11 (45.9%) cases, anaplastic MPNST in 11 (45.9%) cases, and epithelioid MPNST and malignant Triton tumor in one (4.2%) case each. Cytologically, well-differentiated MPNST were composed of polymorphous oval to round cells, small spindle-shaped cells with wavy and comma-like naked nuclei, and a fibrillary, delicate stroma. Anaplastic MPNST, moreover, were composed of anaplastic giant and polymorphous cells. The malignant Triton tumor was composed of oval to round rhabdomyoblastic cells with eccentric nuclei and the epithelioid MPNST of polymorphous and round, epithelial-like cells. The cytological diagnosis of MPNST may be difficult, especially in anaplastic tumors. The correlation between the cytological features and the clinical information--origin of the tumor from a nerve trunk, a preexisting neurofibroma, patients with known history of neurofibromatosis 1--could be indicative of an MPNST diagnosis.

Fine-needle aspiration of neurilemoma (schwannoma). A clinicocytopathologic study of 116 patients

“…Notably, in one of these, cytological smears showed only scattered round to oval cells, some Major pitfalls in the interpretation of aspirates from neurilemoma are spindle cell sarcomas such as leiomyosarcoma (LMS) or MPNST [17][18][19]. In the current study two smears were interpreted initially as LMS/suspicted LMS, and another one as spindle cell sarcoma possibly MPNST.…”

“…The sizes of the lesions ranged from one cm to 20 cm. The neoplasms were seated in the lower extremities (46), upper extremities (28), head and neck (18), chest (10), pelvis and retroperitoneum (4), soft tissue of the sacral region (3), shoulder (2), gluteal region (2), mediastinum (1), groin (1), and abdominal wall (1). The histologic diagnosis in excised neoplasms was neurilemoma in 105 cases and ancient neurilemoma in 11.…”

Cytologic diagnosis of soft tissue tumors

“…Über beeindruckende Ergebnisse der FNP bei Weichteilneoplasien wird vor allem aus Schweden (Lund; [5,6,7,8,9]) und Frankreich (Institut Curie, Paris; [17,18,19,20,21,22]) berichtet. In diesen Zentren ist die FNP bei Verdacht auf einen Weichteiltumor ein integrales Element der multidisziplinären Abklärungsuntersu-chungen.…”

Fine‐needle aspiration biopsy of metastatic malignant melanoma resembling a malignant peripheral nerve sheath tumor

“…The cytomorphologic features of malignant peripheral nerve sheath tumor have been reviewed by Klijanienko et al 9 and described in great detail by Gupta et al 10 In summary MPNST can present with variable cellularity on FNA, usually with clusters of cells arranged in fascicular or parallel pattern. The nuclear pleomorphism is variable with variable mitotic activity.…”