Staging and metastasis search
Correct staging is critical for selecting further management—radiation therapy or chemotherapy—as well as for planning the schedule of subsequent follow-up. Typical pathways of lymphogenous spread include involvement of the left para-aortic and right aortocaval lymph nodes.
For advanced imaging and detection of distant metastases, the following are used:
- Computed tomography (CT) of the brain or spinal cord.
- Bone scintigraphy (bone scan).
- Ultrasound examination (ultrasound) of the liver.
In situations where the stage remains unclear, a short-interval strategy is applied: the patient is scheduled for a repeat CT scan in 6–12 weeks. If pulmonary lesions or para-aortic lymph nodes increase in size during this period, this reliably confirms their metastatic nature.
Secondary malignant involvement: metastases, leukaemia, and lymphoma
In men over 50 years of age, primary testicular malignancies take a back seat. The detection of a mass lesion in this age group should primarily raise suspicion of metastasis. The most common primary sites metastasizing to the scrotum include the prostate, kidney, bronchi, pancreas, urinary bladder, and thyroid gland.
Leukaemia (Leukaemia) Although overt clinical symptoms are rare, the testicular tissue is involved in 50% of patients with acute leukaemia and in 25% with chronic leukaemia. The testis acts as a "sanctuary site" (sanctuary site) for tumour cells because the blood–testis barrier (blood–testis barrier) limits the penetration of chemotherapeutic agents. On ultrasound, this appears as a non-specific diffuse multifocal infiltrative lesion, sometimes with increased echogenicity compared to the healthy parenchyma.
Lymphomas
- Non-Hodgkin lymphoma (Non-Hodgkin lymphoma): occurs in 1–2% of cases, can be the "primary site", and is frequently bilateral.
- Hodgkin lymphoma (Hodgkin lymphoma): involves this organ extremely rarely.
- The ultrasound appearance of lymphomas is typically represented by multifocal discrete hypoechoic and hyperechoic areas.
Benign focal lesions
In approximately 10% of cases, unilocular or multilocular cysts are incidentally discovered during ultrasound examinations in elderly men. Their etiology is associated with past trauma, inflammation, or embryonic remnants. The primary task of the diagnostician is to differentiate them from malignant tumours with a cystic component.
Epidermoid cysts Can have a solid, cystic, or mixed structure. Their radiological markers include:
- Ultrasound: avascular, with a characteristic layered, "whorled appearance" (whorled appearance).
- Elastography: the tissue of the lesion maps as "hard" (hard).
- MRI: T2-weighted images reveal alternating layers of high and low signal intensity.
This is a rare type of pathology where reliable diagnostic imaging and laboratory tests allow for organ-sparing surgery.
Abscess and inflammatory processes An acute abscess (visualised on ultrasound as an area of low or mixed echogenicity) often accompanies epididymitis. However, indolent infections such as tuberculosis can develop covertly and visually mimic cancer. The key to diagnosing a chronic process is the presence of calcifications. If tuberculosis is suspected, percutaneous fine-needle aspiration biopsy is performed, allowing the diagnosis to be verified without unnecessary orchiectomy.
Briefly: answers to topical questions
What diagnostic imaging methods are used to search for distant metastases of testicular cancer?
To search for distant metastases of testicular cancer, cross-sectional imaging methods are used, primarily computed tomography.
- Computed tomography (CT) serves as the basis for staging; in case of suspicion, imaging of the brain or spinal cord is performed.
- Bone scintigraphy (bone scan) is used to detect metastatic involvement of the skeletal system.
- Ultrasonography is used to assess the condition of the liver.
- Magnetic resonance imaging (MRI) and PET-CT (PET-CT) are used in specific clinical situations.
What are the main histological types of primary testicular tumours?
Primary testicular tumours are divided into two main groups based on their origin.
- Germ cell tumours (germ cell tumours) develop from germ cells and account for about 95% of neoplasms. They include typical seminoma, embryonal carcinoma, yolk sac tumour, choriocarcinoma, and teratoma.
- Non-germ cell tumours develop from the sex cord-stromal tissue, feature a benign clinical course, and may be hormonally active.
What specific serum tumour markers are used in testicular tumours?
In testicular tumours, the determination of specific tumour marker levels in the blood is used to assess treatment dynamics and efficacy.
- Alpha-fetoprotein (AFP) — the rate of its decline after courses of chemotherapy is evaluated.
- Human chorionic gonadotropin (hCG / β-hCG) — its elevation in the blood is characteristic, in particular, of typical seminoma.
What ultrasound features are characteristic of typical testicular seminoma?
Typical testicular seminoma is characterised by a specific ultrasound appearance with the replacement of normal tissue.
- Echogenicity — visualised as a mildly hypoechoic (hyporeflective) mass.
- Extent — the tumour frequently replaces almost the entire testis.
- Inclusions — microcalcifications are visible in the normal and altered parenchyma of the organ.
To memorise the main sources of testicular metastases in elderly men, use the rule "3P + TBP": Prostate, Pidney (Kidney), Pancreas, Thyroid, Bladder, Bronchi.
Class and exam questions
What to do if the stage of a testicular tumour remains unclear according to CT data?
It is recommended to wait a short interval (6–12 weeks) and repeat the CT scan. If the dimensions of para-aortic lymph nodes or lung lesions increase during this time, they are considered metastatic.
Why do the testes often become a site of relapse in leukaemias?
The presence of the physiological blood–testis barrier drastically reduces the concentration of chemotherapeutic drugs in the organ tissues, turning it into a kind of "sanctuary site" for the survival of blast cells.
How to reliably differentiate an epidermoid cyst from testicular cancer using imaging modalities?
On ultrasound, it has no blood flow (avascular) and appears "whorled", while on elastography it is assessed as hard. T2 MRI confirms the diagnosis by showing alternating layers of high- and low-intensity signal.
What else to study on this topic
- Morphological classification of testicular germ cell tumours
- Algorithms for the use and interpretation of tumour markers (AFP, hCG, LDH)
- The role of positron emission tomography (PET-CT) in assessing residual masses
- Differential ultrasound diagnosis of acute epididymitis and testicular torsion
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