American Urological Association - Leydig Cell Tumor
Leydig Cell Tumor
- Most common type of SCST.
- Comprises 1-3% testicular tumors.
- 2 age peaks: 5-10 years old and 30-35 years old.
- A few are seen in cryptorchidism.
- Presents a painless testicular mass.
- Tumor cells may produce androgen, estrogens or both and presents with gynecomastia or precocious puberty; symptoms usually regress with excision.
- Gross: Golden-brown to yellow or gray-white cut surface (ave. 3 cm) (image A).
- Large, round or polygonal cells with abundant pink or vacuolated cytoplasm and well-defined cell borders (image B), (image C), & (image D).
- Round or ovoid nuclei, prominent nucleoli, rarely binucleated or multinucleated.
- Intracellular eosinophilic crystalloids or Rienke crystals (40%), lipofuscin pigment (15%).
- Growth patterns: solid (most common), insular, tubular, ribbon-like, and pseudofollicular.
- Mostly are benign tumors; 10% are malignant.
- Leydig cell hyperplasia: Clusters of Leydig cells in intervening interstitium, unlike LCT are small (<0.5 cm) and multifocal.