Testis & epididymis
Sex cord-stromal tumors
Mixed / unclassified sex cord-stromal
Author: Swapnil U. Rane, M.D.
Topic Completed: 1 October 2013
Minor changes: 4 January 2021
Copyright: 2003-2021, PathologyOutlines.com, Inc.
PubMed Search: Sex cord stromal tumors [title]
Table of Contents
Definition / general | Terminology | Epidemiology | Etiology | Clinical features | Laboratory | Radiology description | Prognostic factors | Case reports | Treatment | Gross description | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Immunohistochemistry | Differential diagnosisCite this page: Rane S. Mixed / unclassified sex cord-stromal. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/testismixedscst.html. Accessed January 16th, 2021.
Definition / general
- A sex cord stromal tumor of the testis with mixed sex cord stromal elements or undifferentiated features
- May contain any combination of cell types, including Sertoli cells, Leydig cells, granulosa cells
Terminology
- Also includes undifferentiated stromal tumors with no clearly demonstrable differentiation
Epidemiology
- Rare tumor of descended testis; < 1% of testicular tumors (J Urol 2004;172:2370)
- Can occur in any age group; 1/3 of cases occur in children
- Account for 2/3 of sex cord tumors occurring in children
Etiology
- No specific etiology has been reported for the mixed / undifferentiated sex cord stromal tumors
Clinical features
- Usually present with a painless testicular swelling
- May be painful (Ulster Med J 1997;66:54)
- 15% present with gynecomastia
Laboratory
- Germ cell markers beta-hCG, LDH, alpha fetoprotein are within normal limits
Radiology description
- Solid tumors but may have cystic areas
Prognostic factors
- Similar to other sex cord stromal tumors: poor factors are large size, invasive growth pattern, angiolymphatic invasion, nuclear atypia, mitotic activity, necrosis
- These tumors are usually benign in children < age 10 years
- ~20% in older patients are malignant
Case reports
- 54 year old man with mixture of granulosa and Sertoli cell tumor (Ulster Med J 1997;66:54)
- Included in case series of childhood tumors (J Urol 2004;172:2370)
Treatment
- Similar to other sex cord stromal tumors
- High inguinal orchidectomy routinely done
- Testicular sparing surgery may be attempted if tumor is small, well circumscribed without any invasive features, normal tumor markers and frozen section facilities are available for intraoperative diagnosis
- No proven indication for lymph node dissection if nodes are not enlarged
Gross description
- Gray, tan or yellow solid nodules
- Presence of invasion into tunica, rete testis or adjacent structures predicts malignant / aggressive behavior
Gross images
Images hosted on other servers:
Well circumscribed lower pole testicular tumor
Microscopic (histologic) description
- Mixture of cell types granulosa cell tumor, Leydig cell tumor, thecoma, etc
- One particular cell type may predominate commonly the spindle cell type (Mod Pathol 1997;10:693, Pathol Res Pract 2007;203:759)
Microscopic (histologic) images
Images hosted on other servers:
Tumor is compressing adjacent tunica
Fascicular and storiform spindle cell arrangement
Insular arrangement of cells in hyaline stroma
Irregular ovoid nuclei with longitudinal grooves
Immunohistochemistry
- S100+ (Mod Pathol 1997;10:693), smooth muscle actin+ in spindle elements
- Inhibin variable, calretinin variable, CD99 variable
- Germ cell markers negative
Differential diagnosis
- Pure sex cord stromal tumors: show only one cell type and not more than an occasional microscopic focus of other elements; presence of more than occasional occurrence of two or more sex cord stromal cell types warrants a diagnosis of mixed sex cord stromal tumor
- Sex cord stromal tumor with entrapped germ cells (Am J Surg Pathol 2000;24:535) and mixed germ cell sex cord stromal tumors: show clusters of germ cells in the center of the tumor; only one sex cord stromal cell type present
