Urologic Imaging

What Is the Right Imaging Workflow for Staging Pure Seminoma Testicular Cancer?

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What Is the Right Imaging Workflow for Staging Pure Seminoma Testicular Cancer?

A 28-year-old male presents for follow-up one week after a radical inguinal orchiectomy for a right testicular mass. The final pathology report is on your desk: pure seminoma. His tumor markers, including beta-human chorionic gonadotropin (β-hCG), are normalizing as expected. The immediate clinical question is no longer diagnosis, but staging. You need to determine if the cancer has spread beyond the testis to the retroperitoneal lymph nodes or distant sites like the lungs. This requires a precise, evidence-based imaging strategy to guide the next steps in his care, balancing diagnostic yield with long-term radiation exposure in a young patient. For the initial evaluation of the chest, the American College of Radiology (ACR) rates Radiography as Usually Appropriate.

Who Fits This Clinical Scenario?

This imaging workflow is specifically for patients with a new diagnosis of pure seminoma germ cell tumor confirmed by orchiectomy pathology. The key inclusion criteria are the histopathologic confirmation of “pure seminoma” and the context of initial staging—meaning this is the first set of imaging performed after the definitive diagnosis to determine the extent of disease. This guidance applies to adult males, who represent the vast majority of testicular cancer patients.

It is critical to distinguish this scenario from similar but distinct clinical presentations that require different imaging approaches:

  • Nonseminoma Germ Cell Tumors (NSGCT): If the pathology report indicates any nonseminomatous elements (e.g., embryonal carcinoma, yolk sac tumor, choriocarcinoma, or teratoma), the patient falls into the nonseminoma staging pathway. NSGCTs have different patterns of spread and marker profiles, altering imaging recommendations.
  • Surveillance Imaging: This guidance is not for patients who have already completed initial staging and treatment for Stage I disease and are now undergoing routine surveillance. Surveillance protocols have a different cadence and rationale.
  • Suspected Recurrence: Patients with a history of treated testicular cancer who now present with rising tumor markers or clinical signs of recurrence require a different workup, often involving more advanced imaging modalities from the outset.

What Diagnoses Are You Working Up in This Scenario?

With the primary tumor removed, staging imaging aims to detect metastatic disease. The “differential” in this context is the patient’s clinical stage, which dictates subsequent management, from active surveillance to radiation or chemotherapy. The imaging workup is designed to differentiate between these stages.

Stage I Disease: This is the most common scenario, where the cancer is confined to the testicle and has been completely removed by orchiectomy. Imaging in this case will be negative for any metastatic spread. The goal of imaging is to confidently confirm the absence of disease in the retroperitoneum and chest, allowing the patient to proceed to surveillance or discussion of adjuvant therapy.

Stage II Disease: This stage involves metastasis to the retroperitoneal lymph nodes, the primary landing site for lymphatic drainage from the testis. Seminoma typically spreads in a predictable, stepwise fashion to these nodes. Abdominal and pelvic imaging is crucial for identifying and measuring any enlarged or suspicious lymph nodes, which is the key differentiator between Stage I and Stage II disease.

Stage III Disease: This indicates distant metastasis beyond the retroperitoneal nodes. For seminoma, the most common site of distant spread is the lungs. Less commonly, it can spread to non-regional lymph nodes (like mediastinal or supraclavicular nodes) or visceral organs such as the liver, bone, or brain. The staging workup must include an effective screen for these common distant sites.

Why This Staging Workflow Is Recommended

The initial staging of pure seminoma requires a two-pronged approach: evaluating the chest for distant metastases and evaluating the abdomen and pelvis for nodal disease. The ACR provides distinct recommendations for each body area, which together form the complete staging workup.

For evaluating the chest, Radiography chest is rated Usually Appropriate. This is the preferred initial study because it provides an excellent, low-dose screen for pulmonary metastases, the most common site of distant spread. Given the young age of this patient population, minimizing cumulative radiation exposure is a key principle. A chest radiograph carries a very low radiation dose (☢ <0.1 mSv) while being sufficiently sensitive to detect clinically significant lung nodules that would alter management. While CT chest with IV contrast is more sensitive for tiny nodules, it is rated as May be appropriate and delivers a significantly higher radiation dose (☢☢☢ 1-10 mSv). It is typically reserved for cases where the chest radiograph is equivocal or positive.

For evaluating the abdomen and pelvis, both CT abdomen and pelvis with IV contrast and MRI abdomen and pelvis without and with IV contrast are rated Usually Appropriate. This is where the primary nodal drainage occurs, and cross-sectional imaging is essential.

  • CT with IV contrast is often the practical choice due to its speed, wide availability, and excellent spatial resolution for identifying and measuring retroperitoneal lymph nodes. The IV contrast is critical for delineating nodes from adjacent vessels and organs. Its main drawback is the radiation dose (☢☢☢ 1-10 mSv).
  • MRI with IV contrast is an equivalent alternative that avoids ionizing radiation (O 0 mSv), a significant advantage in young patients who may require future surveillance scans. It offers excellent soft tissue contrast for evaluating nodes. However, it is more expensive, takes longer to acquire, and may be less accessible in some centers.

Studies like FDG-PET/CT whole body are rated Usually not appropriate for initial staging. While highly sensitive, PET/CT is not recommended for routine upfront staging of seminoma as it does not typically change management compared to standard CT or MRI and results in a much higher radiation dose (☢☢☢☢ 10-30 mSv). It is more commonly used to assess residual masses after chemotherapy.

What’s Next After Imaging? Downstream Workflow

The results of the chest radiograph and abdominal/pelvic CT or MRI will determine the patient’s clinical stage and guide the subsequent management plan.

  • Negative Staging Studies: If the chest radiograph and abdominal/pelvic scan are both negative for metastatic disease, the patient is classified as having Stage I pure seminoma. The primary management options are active surveillance, single-agent carboplatin chemotherapy, or radiation therapy to the retroperitoneal nodes. The choice depends on a detailed discussion of risks, benefits, and patient preference.
  • Positive Abdominal/Pelvic Scan: If imaging reveals enlarged retroperitoneal lymph nodes consistent with metastasis (but the chest is clear), the patient has Stage II disease. The next step is typically treatment with either radiation therapy or multi-agent chemotherapy, depending on the bulk of nodal disease.
  • Positive Chest Radiograph: If the chest radiograph shows a suspicious nodule or mass, the immediate next step is a CT chest with IV contrast (rated May be appropriate) to better characterize the finding and search for other, smaller nodules. If confirmed as metastatic disease, the patient has Stage III disease and will require systemic chemotherapy.
  • Indeterminate Findings: If a finding is equivocal (e.g., a borderline-sized lymph node or a tiny, non-specific lung nodule), the next step may be a short-term follow-up scan in 6-12 weeks to assess for stability or growth. In complex cases, an FDG-PET/CT may be considered to assess the metabolic activity of an indeterminate mass.

Pitfalls to Avoid (and When to Get Help)

In staging pure seminoma, several common pitfalls can lead to misclassification or unnecessary radiation exposure. First, avoid ordering a CT chest as the default initial study; a chest radiograph is the ACR-recommended first step for evaluating the lungs. Second, ensure that if you order a CT of the abdomen and pelvis, it is performed with IV contrast, as a non-contrast study is inadequate for evaluating retroperitoneal lymphadenopathy. Third, be aware of post-orchiectomy changes in the inguinal region and spermatic cord remnant, which can be misinterpreted as pathology if the clinical context is not provided to the radiologist. Finally, do not use tumor markers alone to exclude the need for imaging; staging scans are required even if serum markers have normalized. If imaging findings are complex or discordant with the clinical picture, consultation with a multidisciplinary tumor board including urology, oncology, and radiology is essential.

Related ACR Topics and Tools

This article covers a single, specific clinical scenario. For a comprehensive overview of all related presentations and imaging guidelines, it is essential to consult the full ACR topic. The following resources can help you apply these standards in your practice and discuss them with patients.

Frequently Asked Questions

Why not just order a whole-body PET/CT scan for initial staging?

FDG-PET/CT is rated ‘Usually not appropriate’ by the ACR for the initial staging of pure seminoma. Standard cross-sectional imaging (CT or MRI) of the abdomen/pelvis and a chest radiograph are highly effective for detecting clinically significant metastases. PET/CT adds significant radiation dose and cost without typically changing the initial management plan. Its primary role is in assessing residual masses after chemotherapy.

Is CT or MRI better for the abdomen and pelvis in this scenario?

The ACR rates both CT with IV contrast and MRI with IV contrast as ‘Usually Appropriate,’ meaning they are considered equivalent options. The choice often comes down to practical factors. CT is faster and more widely available. MRI avoids ionizing radiation, which is a key advantage in young patients who may need future scans, but it is more expensive and time-consuming. Both are excellent for identifying retroperitoneal lymph node metastasis.

What if my patient has a contraindication to IV contrast for a CT scan?

If a patient has a severe allergy to iodinated contrast or significant renal impairment, an MRI of the abdomen and pelvis is the preferred alternative. The ACR rates ‘MRI abdomen and pelvis without and with IV contrast’ as ‘Usually Appropriate.’ If gadolinium-based contrast for MRI is also contraindicated, a non-contrast MRI (‘May be appropriate’) can still provide valuable information, though it is less sensitive for small nodes.

Do I still need a chest radiograph if I’m already ordering a CT of the abdomen and pelvis?

Yes. A standard CT of the abdomen and pelvis only images the very lowest portion of the lungs. It does not provide an adequate evaluation of the entire chest, which is the most common site for distant testicular cancer metastases. A separate chest radiograph is the recommended, low-dose method to complete the thoracic staging.

How would the imaging plan change if the pathology showed a nonseminoma tumor?

The imaging workflow for nonseminoma germ cell tumors (NSGCT) is different. While the core components (chest and abdomen/pelvis imaging) are the same, CT of the chest is more frequently used upfront for NSGCT due to a higher propensity for small, numerous lung metastases that are better characterized by CT. The specific recommendations are detailed in a separate ACR variant for initial staging of nonseminoma.

Reviewed by Pouyan Golshani, MD, Interventional Radiologist — May 29, 2026