The role of magnetic resonance imaging and computed tomography in the treatment evaluation of retroperitoneal lymph-node metastases of non-seminomatous testicular tumors

ACR Appropriateness Criteria® Staging and Surveillance of Testicular Cancer: 2021 Update

The staging and surveillance of testicular cancer is a complex topic, which integrates clinical, biochemical, and imaging components. The use of imaging for staging and surveillance of testicular cancer is individually tailored to each patient by considering tumor histology and prognosis. This document discusses the rationale for use of imaging by imaging modality during the initial staging of testicular seminoma and nonseminoma tumors and during the planned surveillance of stage IA and IB testicular cancer by histological subtype integrating clinical suspicion for disease recurrence in surveillance protocols. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Magnetic resonance versus computed tomography for the detection of retroperitoneal lymph node metastasis due to testicular cancer: A systematic literature review

INTRODUCTION

It is essential to see if MRI can be used as an alternative to CT for the detection of retroperitoneal lymphadenopathy in patients with testicular neoplasms. By doing so, the amount of radiation received by these young patients might be reduced.

MATERIAL AND METHODS

A systematic literature review was carried out in 5 databases between January 1984 until December 2020. The articles included were randomized and non-randomized clinical trials, cross-sectional studies, cohort, case and control, and retrospective studies that compare the accuracy of MRI against CT to detect retroperitoneal lymph nodes in patients with testicular neoplasms.

RESULTS

The search string initially retrieved 222 non duplicated papers from which a total of 3 studies of diagnostic accuracy were included for analysis. These articles evaluated a total of 127 patients with testicular neoplasm; the sample size per study ranged from 25 to 52 patients, with a mean age between 29-34 years. MRI presented a sensitivity ranging from 98-80% and specificity of 100 % when read by an experienced radiologist. However, when it was read by a radiologist with 1 year of experience, the sensitivity dropped to 78 % and specificity to 91%.

CONCLUSION

This systematic literature review shows a knowledge gap since not much has been published regarding this topic; therefore, randomized clinical trials are mandatory. Research on when to use MRI over CT is necessary to reduce radiation exposure. The authors strongly suggest that readers start researching on this subject.

Ten years of experience with MRI follow-up of testicular cancer stage I: a retrospective study and an MRI protocol with DWI

INTRODUCTION

Patients with testicular cancer (TC) are mainly young and survival rates are high. MRI has several times been proposed to replace CT in follow-up of this patient group to reduce image-related radiation exposure. However, current evidence is scarce for the use of MRI in this context.

AIMS

First, to retrospectively evaluate the ability of MRI of the retroperitoneum and pelvis to detect relapse in patients with TC stage I. Second, to present a relevant MRI protocol of the retroperitoneum and pelvis with diffusion weighted imaging (DWI).

MATERIAL AND METHODS

A retrospective analysis of written radiology reports compared to clinical data from clinical practice from 2010 to 2018. The cohort consists of 2487 MRIs of the retroperitoneum and pelvis in 759 patients with TC stage I (524 seminoma (69.0%), 235 non-seminoma (31.0%)), including 102 patients (13.4%) with confirmed relapse. Confirmed relapse was defined when treatment was initiated for metastatic TC.

RESULTS

Ninety-five patients had a relapse in the MRI scan field during follow-up. MRI of the retroperitoneum and pelvis showed a high sensitivity of 93.8% and a high specificity of 97.4% for detecting TC relapse. The sensitivity for detecting relapse ≥10 mm in short axis lymph node diameter was 100%. The negative predictive value was 99.7%, the positive predictive value was 59.9% and the accuracy was 97.3%.

CONCLUSIONS

MRI of the retroperitoneum and pelvis constitutes a safe alternative to CT in follow-up of patients with TC stage I with both a high sensitivity and a high specificity. We present a robust MRI protocol with DWI and estimate that MRI follow-up of TC stage I can be easily implemented in most modern radiology departments. Registration: Conducted with permission from the Danish Data Protection Agency (1-16-02-323-16) and the Danish Health Authority.

MR Imaging of the Testicular and Extratesticular Tumors: When Do We Need?

Testicular ultrasound is typically the first-line imaging examination in evaluating scrotal pathology. However, MR imaging can often provide valuable additional information, especially when ultrasound and/or clinical examinations are inconclusive. This is particularly evident when encountering testicular or paratesticular lesions, where accurate localization and characterization are paramount for management and prognosis. After reviewing normal scrotal anatomy as seen on MR imaging and offering a sample imaging protocol, the article describes specific indications for scrotal MR imaging and highlights imaging findings unique to various benign and malignant causes.

Lymph node imaging in testicular cancer

Testicular cancer is a rare malignancy mainly affecting young men. Survival for testicular cancer remains high due to the effectiveness of multimodal treatment options. Accurate imaging is imperative to both treatment and follow-up. Both computed tomography (CT) and magnetic resonance imaging (MRI) suffer from size cut-offs as the only distinguishing characteristic of benign vs. malignant lymph nodes and may miss up to 30% of micro-metastatic disease. While functional [positron emission tomography (PET)] imaging may rule out disease in patients with seminoma who have undergone chemotherapy, there is insufficient evidence to recommend its use in other settings. This review highlights the uses and pitfalls of conventional imaging during staging, active surveillance, and post-treatment phases of both seminomatous and non-seminomatous germ cell tumors (NSGCT).

Using Imaging to Predict Treatment Response in Genitourinary Malignancies

CONTEXT

Over the previous2 decades, there have been numerous advancements in the diagnostic evaluation, therapeutic management, and postoperative assessment of genitourinary malignancies.

OBJECTIVE

To present a review of current and novel imaging modalities and their utility in the assessment of therapeutic response in the systemic management of renal, testicular, and prostate cancers.

EVIDENCE ACQUISITION

A PubMed/Medline search of the current published literature inclusive of prospective and retrospective original research, systematic reviews, and meta-analyses was conducted evaluating imaging modalities for renal cell carcinoma, prostate cancer, and testicular cancer. All relevant literature was individually reviewed and summarized to provide a concise description of the currently available imaging modalities and their efficacy in assessing treatment response of the genitourinary malignancies targeted in this review.

EVIDENCE SYNTHESIS

Conventional imaging techniques play a pivotal role in predicting the treatment response of genitourinary malignancies and have, therefore, been incorporated into clinical guidelines. Advancements in imaging technology have led to increased utilization for prognostication of a genitourinary cancer's response to therapy.

CONCLUSIONS

A good understanding of current recommended imaging techniques to evaluate treatment response in genitourinary malignancies is of paramount importance for today's clinician, who faces increasing treatment modalities.

PATIENT SUMMARY

In this review, we summarize available imaging modalities in the evaluation of treatment response in kidney, prostate, or testicular tumors. We believe that a good understanding of current imaging modalities is of paramount importance for healthcare providers treating these cancers.

Role of imaging in testicular cancer: current and future practice

The article provides a summary of the epidemiologic and clinical aspects of testicular malignancy. Current standard imaging and novel techniques are reviewed. Present data and clinical treatment trends have favored surveillance protocols over adjuvant radiation or chemotherapy for low-stage testicular malignancy. This has resulted in increasing numbers of imaging studies and the potential for increased long-term exposure risks. Understanding imaging associated risks as well as strategies to minimize these risks is of increasing importance. The development, validation and incorporation of alternative lower risk highly efficacious and cost-effective imaging techniques is essential.

MR Lymphangiography: Imaging Strategies to Optimize the Imaging of Lymph Nodes with Ferumoxtran-10

Detection of local or regional metastases to lymph nodes is clinically important in virtually any type of primary tumor. Current imaging techniques rely heavily on the size criterion for characterization of nodal disease. However, size can be an ineffective parameter for diagnosis of tumor spread to lymph nodes. Magnetic resonance (MR) imaging performed before and after administration of ferumoxtran-10 is a promising technique for characterization of lymph nodes in patients with various primary tumors. Normal homogeneous uptake of ferumoxtran-10 in nonmetastatic nodes shortens the T2 and T2*, turning these nodes dark, whereas malignant nodes lack uptake and remain hyperintense. To optimize acquisition strategies, the following factors should be considered: the timing of contrast material-enhanced imaging, the section thickness, the imaging plane, and the imaging parameters for T2*-weighted sequences. In addition, MR imaging with ferumoxtran-10 allows presurgical mapping of lymph nodes and quantitative estimation of T2*.

Surgery versus surveillance in stage I non-seminoma testicular cancer

Today, the standard treatment for patients with clinical Stage I non-seminomatous testicular germ cell tumors (NSTGCT) following orchidectomy is either primary retroperitoneal lymph node dissection (RPLND) or close surveillance with cisplatin-based polychemotherapy in case of a relapse. Both treatment modalities provide excellent overall survival rates up to 100%. Consequently, selection of the most appropriate management option is not primarily guided by survival considerations. The choice between the available options, each having its merits and its drawbacks, should be made based on a number of factors including treatment-related morbidity, views and expertise of the physician, patient preferences, the expected degree of patient compliance, and prognostic factor analysis. To date, the role of adjuvant chemotherapy as an alternative management option for patients with clinical Stage I NSTGCT at high risk of occult metastases is limited. This systemic treatment modality would be a realistic alternative if the reliability of prognostic factors to identify high-risk Stage I patients could be improved. This review addresses relevant issues in the management of patients with clinical Stage I NSTGCT to provide information that will allow a rational selection of the most appropriate management option.

Current concepts about testicular cancer

In the past 20 years, testicular cancer, which occurs in the young, has become a curable malignancy; 90% of the patients treated will achieve long-term survival. However, there is a significant morbidity associated with the management of the disease process. The literature was reviewed concerning the current treatment strategies and prognosis, as well as the long-term sequelae of the various diagnostic and therapeutic procedures. Surveillance has become a key element in the management of patients with a primary (stage I) testicular non-seminoma. Although approximately 25% of these patients will relapse, 100% survival can be achieved with cisplatin in combination with etoposide and bleomycin (BEP). Patients with a disseminated non-seminoma are usually treated with 4 courses of BEP; an 80% survival rate can be achieved. The long-term effects of chemotherapy include Raynaud's phenomenon, acral paraesthesia, hyperlipidaemia, nephrotoxicity, infertility and hormonal disturbances. Retroperitoneal lymph node dissection or resection of residual disease following chemotherapy are associated with a low mortality and morbidity rate, ejaculatory dysfunction excepted. However, with specific modifications in technique (e.g. nerve-sparing) antegrade ejaculation can be preserved in the majority of patients. Radiotherapy is used in stage I and II seminoma. With the conventional dose of 25-30 Gy to the retroperitoneal and ipsilateral iliac lymph nodes, temporary dysfunction of the germ and Leydig cells of the remaining testis may occur by scatter radiation. Patients with advanced seminoma are treated with cisplatin-based chemotherapy. To date, testicular cancer patients can receive appropriate curative treatment with acceptable acute toxicity, depending on the therapy given. The detrimental effects of late toxicities require careful study and follow-up. However, little attention is paid currently to quality of life aspects, in particular the impact of the disease and its treatment on general well-being, including sexual function.

Clinical applicability of human in vivo localized phosphorus-31 magnetic resonance spectroscopy of bone and soft tissue tumors

BACKGROUND

Magnetic resonance imaging (MRI) is of restricted value for the in vivo characterization of tumor types. The applicability of phosphorus-31 (31P) magnetic resonance spectroscopy (MRS) in the diagnosis of bone and soft tissue tumors is unknown.

METHODS

A total of 191 consecutive patients (85 females and 106 males; mean age 41 years, range 1-80) with a well-defined bone or soft tissue tumor on MRI were analyzed for additional 31P spectroscopy. Histology and/or cytology was obtained from all tumors. Because of low sensitivity of the 31P nucleus and the contamination of surrounding tissue, only large, superficially located tumors accessible to the surface coil could be accepted for MRS.

RESULTS

Twenty-one patients (11%) could be included in the study. From this remaining group only 12 studies (57%) produced spectra with well resolved phosphorus peaks and an acceptable signal-to-noise ratio. However, these spectra did not allow differentiation between the benign and malignant nature of the lesions. The other 9 studies showed spectra with poor signal intensities and/or poorly defined peaks, making tumor differentiation impossible.

CONCLUSION

Only 6% of the bone and soft tissue tumors produced well defined spectra, which implies that localized 31P MRS cannot be considered as a routine technique in the diagnostic and treatment evaluation of bone and soft tissue tumors.

Retroperitoneal node biopsy in paratesticular rhabdomyosarcoma

Retroperitoneal lymph node dissection (RPLND) was used in 121 Intergroup Rhabdomyosarcoma Study (IRS) III patients with nonmetastatic paratesticular (PT) rhabdomyosarcoma (RMS) to assess retroperitoneal lymph node (RPLN) involvement so as to determine the need for x-ray therapy (XRT). Clinical node evaluation (CNE) was accomplished by a computed tomography (CT) scan in 105 and a sonogram in six. Pathological node evaluation (PNE) was performed in 113: lymphadenectomy (9 bilateral, 85 unilateral) and biopsy in 19. Vincristine and actinomycin D were used for 1 year postoperatively in 89%; all patients who had positive PNE received RPLN XRT. This study compares CNE with PNE and evaluates predictors of relapse and survival.

FINDINGS

There were clinically negative nodes (cN0) in 81% of the 121 patients. Among cN0 patients, 14% had positive nodes (pN1). Of the clinically positive (cN1) patients, 94% had pN1. RPLN relapse occurred in only two of the 121 patients. Initially both had cN0 and one had PNE that was negative. For all 121 patients, the 5-year survival was 91%. For cN0 patients, the 5-year survival was 96% compared with 69% for cN1 patients (P < .001). Among the children in whom treatment failed, nodes were cN1 in 5 of 11 (45%) compared with 15 of 107 (14%) in those whose treatment did not fail (P < .008).

CONCLUSIONS

(1) Results of RPLN imaging studies were negative in 81% of patients with PT RMS (specificity 99%, sensitivity 57%). (2) RPLN recurrence is uncommon (even when RPLN are initially involved) if regional XRT and appropriate chemotherapy are used.(ABSTRACT TRUNCATED AT 250 WORDS)

Integrated approach to the management of patients with advanced germ cell tumors of the testis

Between 1985 and 1991, 63 patients with disseminated germ cell tumors of the testis were treated with initial cisplatin based combination chemotherapy. Complete response was seen in 38% of patients. Adjunctive surgical resection of residual disease was carried out in 26 patients (41%), including the use of intraoperative radiation therapy in two patients with seminoma. Furthermore, two other patients with seminoma and residual mass underwent retroperitoneal irradiation. Salvage chemotherapy was administered to five patients with progressive disease, and only one of these could be salvaged with adjunctive surgery. A disease-free state was achieved in 75% of patients at a mean follow-up period of 30 months.

MRI of the abdomen and pelvis: an update in The Netherlands

MRI with its excellent contrast resolution and direct multiplanar imaging has become a valuable medical tool in diagnostic imaging. Due to physiological motion artifacts, the role of MRI in the abdomen is still under discussion. The use of ultrafast sequences and the development of oral contrast agents, however, offers new promises for abdominal MRI. In the area of the retroperitoneum and pelvis, MRI produces excellent images as motion-artifacts are absent. Up to the end of 1989 clinical MRI in The Netherlands was performed in only four University hospitals; nevertheless these centers proved able to compete with international standards. The rapidly increasing number of MR units that recently became available in The Netherlands could result in a surpassing of CT in many pelvic and abdominal pathological conditions.