Uterus
Stromal tumors
Low grade endometrial stromal sarcoma
Author: Nat Pernick, M.D.
Topic Completed: 1 January 2012
Minor changes: 13 August 2020
Copyright: 2002-2021, PathologyOutlines.com, Inc.
PubMed search: low grade endometrial stromal sarcoma [title]
Table of Contents
Definition / general | Case reports | Treatment | Gross description | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Cytology description | Positive stains | Negative stains | Molecular / cytogenetics description | Differential diagnosis | Additional referencesCite this page: Pernick N. Low grade endometrial stromal sarcoma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/uterusESSlowgrade.html. Accessed January 16th, 2021.
Definition / general
- Also known as endolymphatic stromal myosis
- Slow clinical progression with repeated local recurrences
- 50% recur (may take 10 years), 15% die of metastases (lung) but may be 20 - 30 years later
- Rarely arise from ovary, vagina and peritoneum
Case reports
- 53 year old woman with vaginal bleeding (Case of Week #246)
Treatment
- Adjuvant therapy may reduce recurrence (Ann Oncol 2010;21:2102)
Gross description
- Polypoid mass extending into broad ligament, ovaries and fallopian tubes
- Lymphatic tumor plugs may appear as yellow, ropy or ball-like masses
Gross images
Images hosted on other servers:
tumor mass and
additional infiltrating
tumor nodules
scopically similar
to a uterine
myomatosis
Yellow tumor nodule with necrosis
Microscopic (histologic) description
- Monotonous ovoid to spindly cells with minimal cytoplasm intimately associated with prominent arterioles, closely resembles proliferative endometrial stroma
- Up to 10 - 15 mitotic figures per 10 HPF in most active areas
- Tongue-like infiltration between muscle bundles of myometrium
- Angiolymphatic invasion common
- May exhibit myxoid, epithelioid and fibrous change
- May have foam cells or hyalinization
Microscopic (histologic) images
AFIP images
Dilated and slit-like thin walled vessels are prominent
Dilated vessels and sex cord-like structures
Extensive myometrial infiltration
(Note also slit-like spaces around
tumor masses representing
vascular involvement)
Myometrial infiltration by uniform small tumor cells
like arrangements
blend with intervening
stromal cells
Myometrial lymphatics expanded and
infiltrated by tumor; lobulated contour
of this intravascular tumor is unusual,
resembling intravenous leiomyomatosis
Images hosted on other servers:
Low grade endometrial stromal sarcoma with intravenous extension to the heart
Well defined, cell rich tumor cell aggregates with tongue shaped extensions
Spindled tumor cells with scant cytoplasm and minimal atypia
Intratumoral vessels resembling spiral arteries
Stromal sarcoma on left, PR+
Stromal sarcoma, CD10+
Myometrium stains smooth muscular actin+
Cytology description
- Clean background; usually moderate to marked cellularity with both single cells and stromal fragments; usually also blood vessels interspersed between stromal cell clusters; cells predominantly spindled with scant to moderate cytoplasm, round to ovoid nuclei, fine chromatin; rare mitotic figures, nuclei (Am J Clin Pathol 2007;128:265)
Positive stains
- ER, PR
- Diffuse, strong nuclear immunoreactivity with beta-catenin in 67% (Mod Pathol 2008;21:756)
- AE1 / AE3 in 50% (usually due to CK19+, (Hum Pathol 2008;39:1459)
Negative stains
- Mucin, glycogen
Molecular / cytogenetics description
- JAZF1-JJAZ1 fusion transcript in 50% - 60% (Am J Surg Pathol 2007;31:65)
Differential diagnosis
- Stromal nodule: not infiltrative, no angiolymphatic invasion
- Adenomyosis with sparse glands: usually incidental finding in post-menopausal woman with small and atrophic stromal cells, typical areas of adenomyosis usually present
- Cellular leiomyoma: no infiltration, no angiolymphatic invasion
- Menstrual endometrium within vessels: usually glands are uniformly distributed with bland stroma
- Metastatic lobular carcinoma: check clinical history, strongly keratin+
- Pseudosarcomatous changes in the stroma
- Fragmented lymphoid follicles in biopsies or curettings
- Intravascular leiomyomatosis
Additional references
