Imaging Studies for Germ Cell Tumors

Importance of tumor subtypes in cancer imaging

Cancer therapy has evolved from being broadly directed towards tumor types, to highly specific treatment protocols that target individual molecular subtypes of tumors. With the ever-increasing data on imaging characteristics of tumor subtypes and advancements in imaging techniques, it is now often possible for radiologists to differentiate tumor subtypes on imaging. Armed with this knowledge, radiologists may be able to provide specific information that can obviate the need for invasive methods to identify tumor subtypes. Different tumor subtypes also differ in their patterns of metastatic spread. Awareness of these differences can direct radiologists to relevant anatomical sites to screen for early metastases that may otherwise be difficult to detect during cursory inspection. Likewise, this knowledge will help radiologists to interpret indeterminate findings in a more specific manner.

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Tumor subtypes can be identified based on their different imaging characteristics.

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Awareness of tumor subtype can help radiologists chose the appropriate modality for additional imaging workup.

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Awareness of differences in metastatic pattern between tumor subtypes can be helpful to identify early metastases.

ESMO Consensus Conference on testicular germ cell cancer: diagnosis, treatment and follow-up

The European Society for Medical Oncology (ESMO) consensus conference on testicular cancer was held on 3-5 November 2016 in Paris, France. The conference included a multidisciplinary panel of 36 leading experts in the diagnosis and treatment of testicular cancer (34 panel members attended the conference; an additional two panel members [CB and K-PD] participated in all preparatory work and subsequent manuscript development). The aim of the conference was to develop detailed recommendations on topics relating to testicular cancer that are not covered in detail in the current ESMO Clinical Practice Guidelines (CPGs) and where the available level of evidence is insufficient. The main topics identified for discussion related to: (1) diagnostic work-up and patient assessment; (2) stage I disease; (3) stage II-III disease; (4) post-chemotherapy surgery, salvage chemotherapy, salvage and desperation surgery and special topics; and (5) survivorship and follow-up schemes. The experts addressed questions relating to one of the five topics within five working groups. Relevant scientific literature was reviewed in advance. Recommendations were developed by the working groups and then presented to the entire panel. A consensus vote was obtained following whole-panel discussions, and the consensus recommendations were then further developed in post-meeting discussions in written form. This manuscript presents the results of the expert panel discussions, including the consensus recommendations and a summary of evidence supporting each recommendation. All participants approved the final manuscript.

Imaging of Metastatic Germ Cell Tumors in Male Patients From Initial Diagnosis to Treatment-Related Toxicities: A Primer for Radiologists

OBJECTIVE. This review describes the influence of histology and metastatic sites on prognosis in male patients with metastatic germ cell tumors (GCTs) and explains the role imaging in assessing therapeutic response, residual disease, recurrence, sand treatment-related toxicities. CONCLUSION. Seminomatous and nonseminomatous GCTs differ in imaging appearance, pattern of spread, and prognosis, and an organ-based approach is helpful in prognostication. Multimodality imaging aids in accurate staging, prognostication, characterization of treatment response, and identification of therapy-related toxicity.

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).

Usefulness and role of magnetic resonance imaging in a case of complete androgen insensitivity syndrome

Complete androgen insensitivity syndrome (CAIS) is an X-linked, recessive disorder caused by mutations of the androgen receptor (AR), in which genetic males (46,XY) show female external genitalia. Individuals with CAIS have mostly normal external genitalia, lack of Müllerian structures (Fallopian tubes, uterus, proximal portion of the vagina) and undescended testes (intra-abdominal, inguinal, or labial). Management and diagnosis of CAIS should be undertaken by a multidisciplinary team of experts in sexual development disorders. Gonadectomy represents a standard therapeutic choice to prevent testicular malignancy in the prepubertal period, with subsequent hormonal replacement therapy, or in late adolescence, after completion of pubertal development. Imaging examinations play a pivotal role in the diagnosis, assessment, and detection of the gonads before surgical treatments. Magnetic resonance imaging (MRI) is the gold standard to diagnose and locate the gonads, and to plan laparoscopic gonadectomy and gonadic surveillance, in particular in the increasingly large number of patients who decide to delay or ultimately not to undergo gonadectomy. We present a case of a 14-year-old female with primary amenorrhea.

Role of imaging in the diagnosis and management of complete androgen insensitivity syndrome in adults

Complete androgen insensitivity syndrome is an X-linked recessive androgen receptor disorder characterized by a female phenotype with an XY karyotype. Individuals affected by this syndrome have normal female external genitalia but agenesis of the Müllerian duct derivatives, that is, absence of the Fallopian tubes, uterus, cervix, and the proximal part of the vagina, with presence of endoabdominal, labial, or inguinal testes. The estimated prevalence is between 1 and 5 in 100,000 genetic males. Complete androgen insensitivity syndrome can be diagnosed as a result of mismatch between the prenatal sex prediction and the phenotype at birth, can be detected by chance, or remain undetected until investigations for primary amenorrhea. Imaging can be important both to diagnose the pathology and to localize gonads prior to surgical treatment. In this paper, we present three cases of complete androgen insensitivity syndrome in adult women of 34, 22, and 38 years old.

Evaluation and management of disorders of sex development: multidisciplinary approach to a complex diagnosis

Various disorders of sex development (DSD) result in abnormal development of genitalia, which may be recognized at prenatal ultrasonography, immediately after birth, or later in life. Current methods for diagnosing DSD include a thorough physical examination, laboratory tests to determine hormone levels and identify chromosomal abnormalities, and radiologic imaging of the genitourinary tract and adjacent organs. Because of the complex nature of DSD, the participation of a multidisciplinary team is required to address the patient's medical needs as well as any psychosocial issues that the patient or the family may encounter after the diagnosis. The first step in the management of DSD is sex assignment, which is based on factors such as the genotype; the presence, location, and appearance of reproductive organs; the potential for fertility; and the cultural background and beliefs of the patient's family. The primary goal of sex assignment is to achieve the greatest possible consistency between the patient's assigned sex and his or her gender identity. Once the sex is assigned, the next step in management might be surgery, hormone therapy, or no intervention at all. Patients with ovotesticular DSD and gonadal dysgenesis may require a gonadectomy, followed by reconstructive surgery. Some patients may need hormone replacement therapy during puberty. An understanding of the immediacy of families' need for sex assignment and clinicians' need for reliable diagnostic imaging results will help radiologists participate effectively in the prenatal and postnatal assessment of patients with DSD.

Frequency of computed tomography examinations in the follow-up care of testicular cancer patients - an evaluation of patterns of care in Germany

BACKGROUND

Exposure to radiation resulting from diagnostic imaging procedures probably increases late cancer risk. Patterns of care regarding the application of computed tomography (CT) imaging in testicular cancer patients were investigated.

METHODS

The database of a large German health insurance company comprising 850,000 insured men was searched for cases of testicular cancer arising in the years 2005 and 2006. The number of CT scans applied during a 3-year period of follow-up was noted for each individual patient and the resulting cumulative radiation dose was estimated. The number of CT scans actually observed was compared to guideline recommendations.

RESULTS

177 patients were identified. Within the 3-year observation period, patients received a mean of 4.4 CT scans (standard error: 0.4) whereas a number of 6.2 would have been expected according to contemporary guidelines. Patients were exposed to an estimated total median diagnostic radiation dose of 30 millisieverts (mSv) (interquartile range: 10-54 mSv).

CONCLUSION

There is a considerable gap between recommendation and actual performance regarding the number of CT scans applied to testicular cancer patients. Unfamiliarity of clinicians with guidelines as well as poor acceptance of high numbers of CT scans scheduled may have contributed to create this particular pattern of care.