Testis & paratestis
Sex cord stromal tumors
Mixed and other sex cord stromal tumors
Author: Swapnil U. Rane, M.D.
Last author update: 1 October 2013
Last staff update: 28 March 2022
Copyright: 2003-2023, PathologyOutlines.com, Inc.
PubMed Search: Sex cord stromal tumors [title]
Table of Contents
Definition / general | Terminology | Epidemiology | Etiology | Clinical features | Comparison of mixed sex cord stromal tumors with and without gonadoblastoma | Laboratory | Radiology description | Prognostic factors | Case reports | Treatment | Gross description | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Positive stains | Negative stains | Molecular / cytogenetics description | Differential diagnosisCite this page: Rane S. Mixed and other sex cord stromal tumors. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/testismixedscst.html. Accessed March 24th, 2023.
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
Comparison of mixed sex cord stromal tumors with and without gonadoblastoma
- Mixed sex cord stromal tumor with gonadoblastoma:
- Associated with disorders of sexual development (gonadal dysgenesis [pure or mixed], altered karyotype, pseudohermaphrodites with streak gonads)
- Leydig-like cells and lutein cells
- Virilization
- Proliferative activity only in germ cells
- Mixed sex cord stromal tumor without gonadoblastoma:
- Genetically and phenotypically normal individuals
- No Leydig-like cells and lutein cells
- No endocrine effects usually; if present, usually feminization
- Proliferative activity in sex cord stromal and germ cell components
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)
- Adult man (Am J Clin Pathol 1981;75:565)
- Incidental finding (J Urol 1995;154:1479)
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
Positive stains
- Germ cells: variable AE1 / AE3 in a paranuclear dot pattern; variable Ki67 (depending on grade)
- Sex cord stromal elements: variable inhibin, calretinin, CD99
- Spindle elements: S100, smooth muscle actin (Mod Pathol 1997;10:693)
Negative stains
Molecular / cytogenetics description
- Ovarian tumors have c-kit mutations (seen in seminomas) and excess genetic material on #12p (seen in all germ cell tumors) but no genetic aberrations identified in testicular tumors (Virchows Arch 2006;448:612)
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
