Prostate gland & seminal vesicles
Mesenchymal tumors
Leiomyosarcoma
Author: Kenneth A. Iczkowski, M.D.
Last author update: 1 January 2017
Last staff update: 11 January 2021
Copyright: 2003-2023, PathologyOutlines.com, Inc.
PubMed search: prostatic leiomyosarcoma
Table of Contents
Definition / general | Essential features | Epidemiology | Etiology | Clinical features | Microscopic (histologic) description | Microscopic (histologic) images | Positive stains | Negative stains | Molecular / cytogenetics description | Differential diagnosis | Additional referencesCite this page: Iczkowski KA. Leiomyosarcoma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/prostatelms.html. Accessed September 30th, 2023.
Definition / general
- The most common malignant spindle cell tumor of the prostate
Essential features
- Rare, but the most common prostatic sarcoma
- Aggressive
- Nonsarcomatous spindle cell proliferations must be ruled out
Epidemiology
- Leiomyosarcoma is the most common prostatic sarcoma in adults; it may also occur in children
- Fewer than 200 cases are reported
Etiology
- Some cases may follow radiation or hormonal therapy for adenocarcinoma of the prostate (Adv Urol 2015;2015:485786)
Clinical features
- Tumor causes obstruction, and involves adjacent organs
- Can initially present with chest metastasis (J Cancer Res Ther 2013;9:743) or in other odd ways
- Tends to recur
- Metastases to liver and lung
- Mean survival 3 - 4 years
Microscopic (histologic) description
- A spindle cell proliferation with atypia and mitotic activity
- Focal necrosis may be seen
Microscopic (histologic) images
Contributed by Athanase Billis, M.D.
Various images
Images hosted on other servers:
Giant neoplastic cells (a) and multifocal necrosis (b)
Smooth muscle actin (a) and vimentin (b)
Positive stains
- Positive immunohistochemical markers are CD44, smooth muscle actin and calponin, with variable desmin
Negative stains
- PSA, cytokeratins
- Notably, leiomyosarcoma is negative for CD117 and CD34, ruling out GIST and solitary fibrous tumor
Molecular / cytogenetics description
- Cytogenetics may disclose chromosome 2, 3, 9, 11 and 19 clonal rearrangements
Differential diagnosis
- Nodular hyperplasia with atypical changes: not invasive, no mitotic figures (Cancer 1995;76:1422, Sarcoma 2008;2008:458709)
- Postoperative spindle cell nodules: clinical history, not invasive, no atypical mitotic figures
- Rectal GIST: may be difficult to differentiate (Nihon Hinyokika Gakkai Zasshi 2001;92:624); but different immunoreactivities
Additional references
