Rarely (5% or less), testicular cancer may present with systemic endocrine symptoms or paraneoplastic symptoms. Gynecomastia is the most common in this category, occurring in approximately 2% of germ cell tumors and more commonly (20%–30%) in Leydig cell tumors of testis.6 Classically, these patients are either 6- to 10-year-old boys with precocious puberty or young men (mid 20s-mid 30s) with a combination of testicular mass, gynecomastia, loss of libido, and impotence. Workup typically reveals increased beta-HCG levels in blood.
Anti-Ma2-antibody-associated limbic encephalitis is the most common (and still quite rare) paraneoplastic complication associated with testicular germ cell tumors. The Ma2 antigen is selectively expressed in the neuronal nucleoli of normal brain tissue and the testicular tumor of the patient. Importantly, in a subset of these patients, the treatment of testicular cancer may result in improvement of symptoms of encephalitis.7
The first step in the diagnosis of testicular neoplasm is a physical exam. This should include a bimanual examination of the scrotal contents, starting with the normal contralateral testis. Normal testicle has a homogeneous texture and consistency, is freely movable, and is separable from the epididymis. Any firm, hard, or fixed mass within the substance of the tunica albuginea should be considered suspicious until proven otherwise. Spread to the epididymis or spermatic cord occurs in 10% to 15% of patients and examination should include these structures as well.3 A comprehensive system-wise examination for features of metastatic spread as discussed above should then be performed. If the patient has cryptorchidism, ultrasound is a mandatory part of the diagnostic workup.
If clinical evaluation suggests a possibility of testicular cancer, the patient must be counseled to undergo an expedited diagnostic workup and specialist evaluation, as a prompt diagnosis and treatment is key to not only improving the likelihood of cure, but also minimizing the treatments needed to achieve it.
Role of Imaging
Scrotal ultrasound is the first imaging modality used in the diagnostic workup of patient with suspected testicular cancer. Bilateral scrotal ultrasound can detect lesions as small as 1 to 2 mm in diameter and help differentiate intratesticular lesions from extrinsic masses. A cystic mass on ultrasound is unlikely to be malignant. Seminomas appear as well-defined hypoechoic lesions without cystic areas, while NSGCTs are typically inhomogeneous with calcifications, cystic areas, and indistinct margins. However, this distinction is not always apparent or reliable. Ultrasound alone is also insufficient for tumor staging.8 For these reasons, a radical inguinal orchiectomy must be pursued for accurate determination of histology and local stage.
If testicular ultrasound shows a suspicious intratesticular mass, the following workup is typically done:
- Measurement of serum tumor markers (beta-HCG, AFP and LDH);
- CT abdomen and pelvis with and without contrast;
- Chest radiograph anteroposterior and lateral views, or CT chest with and without contrast if clinically indicated;
- Any additional focal imaging based on symptoms (eg, magnetic resonance imaging [MRI] scan with and without contrast to evaluate the brain if the patient has CNS symptoms).
CT scan is the preferred imaging modality for staging of testicular cancers, specifically for evaluation of the retroperitoneum, as it is the predominant site for metastases.9 CT scan should encompass the abdomen and pelvis, and contrast-enhanced sequences should be obtained unless medically contraindicated. CT scan of the chest (if not initially done) is compulsory should a CT of abdomen and pelvis and/or a chest radiograph show abnormal findings.