Testicular Microlithiasis and Small Testicular Lesions: Clinical Approach for Ultrasound Physicians
Testicular Microlithiasis (TM): Definition and Sonographic Appearance
TM is a rare condition characterized by small calcifications within testicular parenchyma measuring less than 3 mm (Textbook of Diagnostic Sonography, 2023). On ultrasound, TM is visualized as miniature non-shadowing calcified deposits, typically observed bilaterally (EFSUMB, 2026). Microlithiasis is more frequently a bilateral condition.
Role of Multiparametric Ultrasound (MPUS)
According to EFSUMB (Bertolotto et al., 2026, PICO 9), in the diagnosis of TM, B-mode imaging visualizes calcifications, while color Doppler ultrasound (CDUS) and elastography are applied with limited efficacy. Research demonstrates that CDUS does not provide significant impact on management of patients with TM.
Oncological Context
TM is not directly associated with testicular cancer; however, certain concerns have been raised. Epidemiological differences have been noted: in Caucasian men, particularly from Scandinavian countries, higher oncological risk is observed with lower TM prevalence; in men of African descent, the opposite trend is observed (EFSUMB, 2026).
Follow-up and Referral
The question of whether follow-up is necessary for TM in the absence of other risk factors remains controversial (Richenberg et al., Eur Radiol 2012; ESUR scrotal imaging subcommittee, Eur Radiol 2015). Specific follow-up intervals and referral criteria are not detailed in the provided excerpts — [to be clarified] according to current ESUR/EFSUMB recommendations.
Simple Intratesticular Cysts
A simple testicular cyst is a benign lesion, occurring in approximately 5–10% of men on scrotal ultrasound (Medtrain consensus panel, 2026). Cysts are incidental findings and require no treatment (Textbook of Diagnostic Sonography, 2023).
Sonographic criteria for simple cyst:
| Feature | Characteristic |
|---|---|
| Content | Anechoic |
| Wall | Thin, smooth |
| Margins | Sharp |
| Posterior acoustic enhancement | Present |
| Internal echoes/septa | Absent |
| Vascularity on CDUS/EDUS | Absent |
Cysts more frequently occur in the region of the testicular mediastinum (rete testis cysts). Isolated simple cysts in men older than 40 years meeting all criteria are considered benign with virtually absent malignant potential; tumor markers (AFP, hCG, LDH) typically remain unchanged with typical imaging appearance (Medtrain consensus panel, 2026).
Differential Diagnosis
When evaluating small testicular lesions, consideration should be given to cystic teratoma (heterogeneous content, septa) and other pathologies. Complete differential diagnosis with sonographic criteria is not detailed in the provided excerpts — [to be clarified].
Frequently asked questions
What is the size of calcifications in testicular microlithiasis?
Microcalcifications in TM measure less than 3 mm; they are non-shadowing and typically located bilaterally (Textbook of Diagnostic Sonography, 2023; EFSUMB, 2026).
Should color Doppler ultrasound and elastography be applied in TM?
According to EFSUMB (2026), color Doppler ultrasound and elastography have limited efficacy; CDUS does not provide significant impact on management of patients with TM. B-mode imaging is the primary imaging modality.
Is microlithiasis associated with testicular cancer?
No direct causal relationship exists; however, concerns have been raised. Racial differences have been noted in both TM prevalence and oncological risk (EFSUMB, 2026).
Does a simple testicular cyst require treatment?
No. Simple cysts are incidental findings requiring no treatment. In men older than 40 years meeting all criteria for a simple cyst, they are considered benign (Medtrain consensus panel, 2026; Textbook of Diagnostic Sonography, 2023).
What sonographic features confirm a simple intratesticular cyst?
Anechoic content, thin smooth wall, sharp margins, posterior acoustic enhancement, absence of echoes, septa, and vascularity on CDUS/EDUS (Medtrain consensus panel, 2026).