Diagnostic Ultrasound - Abdomen and Pelvis

Gonadal Stromal Tumors, Testis
TERMINOLOGY
Abbreviations
• Gonadal stromal tumors (GST)
Synonyms
• Also called nongerm cell tumors, interstitial cell tumors, or
sex cord tumors
Definitions
• Leydig cell tumor (LCT): Arises from interstitial cells
• Sertoli cell tumor (SCT): Arises from sustentacular cells
lining seminiferous tubules
• Granulosa cell tumor (GCT): Rare sex cord tumor
• Gonadoblastoma: Contains both stromal and germ cell
elements
IMAGING
General Features
• Location
○ Bilateral in 3%
• Size
○ Benign tumors: Usually < 3 cm
○ Malignant tumors: Usually > 5 cm
• Morphology
○ Well circumscribed, round/lobulated
Ultrasonographic Findings
• Grayscale ultrasound
○ May be indistinguishable from germ cell tumors
○ LCT: Small, solid, hypoechoic intratesticular mass
– Larger tumors: Hemorrhage or necrosis leads to
heterogeneous echo pattern
– May occasionally show cystic change
○ SCT: Small, hypoechoic mass, hemorrhage may lead to
heterogeneity
– Solid and cystic components
– ± punctate calcification; large, calcified mass in largecell
calcifying Sertoli cell tumor
○ GCT: Well-defined hypoechoic mass with solid and cystic
components
○ Adult testicular GCTs are rare sex cord-stromal tumors
MR Findings
• T2WI: Low signal intratesticular mass ± high signal fibrous
capsule rim and high signal intensity foci internally
secondary to central scars
Imaging Recommendations
• Best imaging tool
○ High-resolution US (9-15 MHz)
DIFFERENTIAL DIAGNOSIS
Testicular Germ Cell Tumors
• May be indistinguishable from stromal tumors on US
Testicular Metastases, Lymphoma, Leukemia
• Often multiple; otherwise indistinguishable
Intratesticular Hematoma
• Scrotal trauma, no internal color flow in hematoma
PATHOLOGY
General Features
• Associated abnormalities
○ LCT: Klinefelter syndrome
○ SCT: Peutz-Jeghers syndrome and Carney syndrome
• Leydig cell tumors: 3% of all testicular tumors
○ 90% benign, 3% bilateral
○ Most common, may produce testosterone
• Sertoli cell tumors: 1% of all testis tumors
○ 85-90% benign
○ May produce estrogen/müllerian inhibiting factor
• Granulosa cell tumor: Rare
○ Juvenile GCTs are typically benign; 20% of testicular
adult GCTs have been reported to present malignant
behavior
CLINICAL ISSUES
Presentation
• Most common signs/symptoms
○ Painless testicular enlargement
○ 30% of patients have endocrinopathy secondary to
testosterone or estrogen production by tumor
– Gynecomastia, impotence, ↓ libido in adults
Demographics
• Age
○ LCT: 30-60 years; 25% occur before puberty
○ SCT: All age groups; 1/3 < 12 years
○ GCT: Juvenile type in infants; adult type in patients aged
16-77 years
Natural History & Prognosis
• Malignant tumors metastasize in same pattern as testicular
germ cell tumors
Treatment
• Orchidectomy or testis-sparing surgery
DIAGNOSTIC CHECKLIST
Image Interpretation Pearls
• Consider stromal tumor in any patient with endocrinopathy
and testicular mass
SELECTED REFERENCES
1. Miliaras D et al: Adult type granulosa cell tumor: a very rare case of sex-cord
tumor of the testis with review of the literature. Case Rep Pathol.
2013:932086, 2013
2. Leonhartsberger N et al: Increased incidence of Leydig cell tumours of the
testis in the era of improved imaging techniques. BJU Int. 108(10):1603-7,
2011
3. Tallen G et al: High reliability of scrotal ultrasonography in the management
of childhood primary testicular neoplasms. Klin Padiatr. 223(3):131-7, 2011
4. Maizlin ZV et al: Leydig cell tumors of the testis: gray scale and color Doppler
sonographic appearance. J Ultrasound Med. 23(7):959-64, 2004
5. Carmignani L et al: High incidence of benign testicular neoplasms diagnosed
by ultrasound. J Urol. 170(5):1783-6, 2003
6. Woodward PJ et al: From the archives of the AFIP: tumors and tumorlike
lesions of the testis: radiologic-pathologic correlation. Radiographics.
22(1):189-216, 2002
7. Ulbright TM et al. Tumors of the testis, adnexa, spermatic cord, and scrotum.
In: Atlas of Tumor Pathology. Washington, DC: Armed Forces Institute of
Pathology. 1–290, 1999
Diagnoses: Scrotum
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