Improved outcomes in metastatic germ cell cancer: results from a large cohort study

Sarcomatoid Yolk Sac Tumor Harbors Somatic Mutations That Are Otherwise Rare in Testicular Germ Cell Tumors

In testicular germ cell tumors (TGCTs), components with nonspecific sarcomatous features that express keratins and glypican 3 are classified as sarcomatoid yolk sac tumor (SYST). SYST is most frequently seen in metastatic sites after chemotherapy. Like so-called "somatic-type" malignancies arising in TGCTs, SYST is markedly resistant to systemic therapy and has a more aggressive clinical course than conventional types of TGCT. However, the clinicopathologic and molecular features of SYST remain incompletely described. This study evaluated a multi-institutional series of 20 SYSTs using massively parallel sequencing and p53 immunohistochemistry. The histologic and clinical characteristics of the cases were also assessed, including analyses of disease-specific outcomes. DNA sequencing identified somatic mutations in 12/20 cases (60%), including recurrent TP53 and RIF1 mutations (present in 4/20 cases, 20% each). In 3 of the 4 SYST with TP53 mutations, there was molecular evidence of loss of heterozygosity. Immunohistochemistry demonstrated diffuse overexpression of p53 protein in 3/4 (75%) cases with TP53 mutations. The remaining TP53-mutant case demonstrated multifocal overexpression of p53, suggestive of subclonal inactivation of the gene. Overexpression of p53 protein was not seen in any of 15 TP53 wild-type cases evaluated by immunohistochemistry. A subset of 4 cases underwent RNA sequencing (fusion panel), which demonstrated the absence of oncogenic gene fusions. A 2-tiered grading system based on 3 histologic parameters (cellularity, number of mitoses, and necrosis) demonstrated that high-grade SYSTs have a higher risk of disease-specific death compared to low-grade tumors. The risk of disease-specific mortality was also higher in SYSTs with somatic mutations. In conclusion, this study demonstrated that 60% of SYSTs harbor somatic oncogenic mutations that are otherwise rare in TGCTs, and the presence of these mutations is associated with an aggressive clinical course. In addition, the results presented herein suggest that grading SYSTs may be clinically relevant.

Testicular Germ Cell Tumors: Classification, Pathologic Features, Imaging Findings, and Management

Testicular germ cell tumors (TGCTs) demonstrate a wide variety of histopathologic, genetic, pathogenetic, and immunocytochemical characteristics and various clinical-biologic profiles and prognoses. Most TGCTs arise from an intratubular precursor cell referred to as germ cell neoplasia in situ (GCNIS), which is an embryonic germ cell with the potential to differentiate into a plethora of embryonic and extraembryonic lineages. Advances in pathologic examination and genetics paved the way for the 2016 World Health Organization (WHO) classification system, which recognizes two pathogenetically distinct groups of TGCTs. Although postpubertal tumors originate from GCNIS, almost all prepubertal tumors belong to the non-GCNIS category. Molecular testing for chromosome 12p amplification helps to distinguish the two tumor categories. Imaging techniques such as US, CT, MRI, and fluorine 18 (¹⁸F)-fluorodeoxyglucose PET/CT are pivotal to the diagnosis and staging, evaluation of complications and treatment response, and long-term surveillance of TGCTs. In addition, select MRI findings may help to differentiate a seminoma from a nonseminomatous mixed TGCT. Accurate diagnosis of TGCTs has therapeutic and prognostic implications. Although seminomas show exquisite response to chemotherapy and radiation therapy, postpubertal teratomas are highly resistant to both. The 2016 WHO classification system introduced changes in the diagnosis and management of TGCTs, including the development of new treatment and follow-up guidelines. Radiologists play an essential role in the optimal treatment of patients with TGCTs. Online supplemental material is available for this article. ©RSNA, 2021.

Outcomes of men with HIV and germ cell cancer: Results from an international collaborative study

BACKGROUND

Previous studies have shown that men with HIV and germ cell cancer (HIV-GCC) have inferior overall survival (OS) in comparison with their HIV-negative counterparts. However, little information is available on treatments and outcomes of HIV-GCC in the era of combination antiretroviral therapy (cART).

METHODS

This study examined men living with HIV who were 18 years old or older and had a diagnosis of histologically proven germ cell cancer (GCC). The primary outcomes were OS and progression-free survival (PFS).

RESULTS

Data for 89 men with a total of 92 HIV-GCCs (2 synchronous GCCs and 1 metachronous bilateral GCC) were analyzed; among them were 64 seminomas (70%) and 28 nonseminomas (30%). The median age was 36 years, the median CD4 T-cell count at GCC diagnosis was 420 cells/µL, and 77% of the patients on cART had an HIV RNA load < 500 copies/mL. Stage I disease was found in 44 of 79 gonadal GCCs (56%). Among 45 cases with primary disseminated GCC, 78%, 18%, and 4% were assigned to the good-, intermediate-, and poor-prognosis groups, respectively, of the International Germ Cell Cancer Collaborative Group. Relapses occurred in 14 patients. Overall, 12 of 89 patients (13%) died. The causes of death were refractory GCC (n = 5), an AIDS-defining illness (n = 3), and other causes (n = 4). After a median follow-up of 6.5 years, the 5- and 10-year PFS rates were 81% and 73%, respectively, and the 5- and 10-year OS rates were 91% and 85%, respectively.

CONCLUSIONS

The 5- and 10-year PFS and OS rates of men with HIV-GCC were similar to those reported for men with HIV-negative GCC. Patients with HIV-GCC should be managed identically to HIV-negative patients.

LAY SUMMARY

Men living with HIV are at increased risk for germ cell cancer (GCC). Previous studies have shown that the survival of men with HIV-associated germ cell cancer (HIV-GCC) is poorer than the survival of their HIV-negative counterparts. This study examined the characteristics, treatments, and outcomes of 89 men with HIV-GCC in the era of effective combination antiretroviral therapies. The long-term outcomes of men with HIV-GCC were similar to those reported for men with HIV-negative GCC. Patients with HIV-GCC should be managed identically to HIV-negative patients.

Visible haematuria-an unusual presentation of metastatic testicular mixed germ cell tumour

A 29-year-old male patient presented to the emergency department with haematuria and flank pain. Ten months agopreviously, he had undergone orchidectomy and adjuvant chemotherapy for a testicular mixed germ cell tumour. Cystoscopy revealed a large bladder wall mass. The final diagnosis of yolk sac tumour was established after transurethral resection of the lesion. The patient was treated with salvage chemotherapy and placed on short-interval biochemical and radiological surveillance to assess treatment response.