Brain Metastases as Presenting Feature in 'Burned Out' Testicular Germ Cell Tumor

'Burned-out' syndrome of testicular teratoma: A case report

The majority of testicular tumors are germ cell tumors (GCTs) which, although rare, frequently present in young adults. In exceptional circumstances, spontaneous regression of the primary tumor occurs. The appellation ‘burned-out’ is applied to situations in which a metastatic GCT is found to be present, accompanied by histological regression of the primary testicular lesion. It is of crucial importance that a clinical examination of the testis is performed, and scrotal sonography is essential in the preliminary diagnosis of such neoplasms. In the present case report, a burned-out, non-seminomatous testicular GCT case is described. A CT scan revealed that a 29-year-old male patient who was experiencing loss of weight and appetite had retroperitoneal and mediastinal masses. A testicular examination did not reveal the presence of any palpable lesion, and an ultrasound examination of the scrotum disclosed a normal left testis and an atrophic right testicle with heterogeneous architecture, but with no evidence of a tumor. Chemotherapy was administered to the patient following surgical intervention into the retroperitoneal and mediastinal mass. It is evident that it remains problematic to accurately differentiate between a primary retroperitoneal tumor and a metastatic testicular tumor with an occult testicular primary or a ‘burned-out’ testicular cancer. The burned-out phenomenon is a rare occurrence, and further research into its pathogenesis is required. Both the rarity of this phenomenon and the difficulties encountered in diagnosis prompted the writing of the present case report, especially considering that teratomas are categorized as belonging to the histology group that shows the least likelihood of regressing.

Burned-out Post Pubertal Teratoma Presenting as a Liver Metastases in a 34-Year-Old Male

Germ cell teratomas belong to non-seminomatous germ cell tumors and account for 95% of malignant testicular tumors. Regarding the current World Health Organization (WHO) criteria, testicular teratomas are divided into prepubertal and post-pubertal subtypes based on patients’ age. The term “burned-out testicular tumor” is a very rare condition referring to a regressed testicular tumor which presents with its metastases without any clinical finding in the testicle. Metastasis can be the presentation of post-pubertal teratoma in 22-37% of cases. In scar associated teratoma (burn-out component), the metastasis rate is 66%. We reported a rare case of post-pubertal teratoma in a 34-year-old male who presented with multiple liver masses initially. Liver biopsy revealed poorly differentiated adenocarcinoma probably of gastrointestinal (GI) tract origin. The upper and lower GI endoscopy were normal. Scrotal ultrasonography showed a hypoechoic cystic intratesticular lesion in the left testis. The patient underwent radical orchiectomy and the histopathologic examination revealed post-pubertal teratoma with burned out component. The patient underwent proper treatment and is still under follow up. As a result, in a young male patient who presented with a retroperitoneal mass or poorly differentiated carcinomas of an unknown primary site, using light microscopy and immunohistochemical profiling alone may be inadequate. Therefore, scrotal screening and physical examination of the scrotum and bilateral testis should be considered to exclude possibility of a metastatic progression from a testicular germ cell neoplasia.

The decisive role of molecular pathology in presumed somatic metastases of type II testicular germ cell tumors: report of 2 cases

Background

Molecular diagnostics can be decisive in the differential diagnosis between a somatic metastasis of type II testicular germ cell tumor (TGCT) or a second primary carcinoma. This is in line with recent recommendations from the International Society of Urological Pathology, based on an international survey which showed that molecular testing is currently only performed by a minority of urological pathologists.

Case presentations

This case report illustrates the necessity of molecular testing in two patients with a history of type II TGCT and a metastatic (retro) peritoneal carcinoma years later. The genetic hallmark of type II TGCT, chromosome 12p gain, was studied by fluorescence in situ hybridization and whole genome methylation profiling in case 1, and by single nucleotide polymorphism (SNP)-array in case 2. Next generation sequencing (NGS) was used to further explore clonality between the primary TGCT and peritoneal metastasis in case 2. In case 1, chromosome 12p gain was found in the primary type II TGCT and in the acinar cell carcinoma of the metastatic malignancy. In case 2, SNP array showed 12p gain in the epithelial component of the primary teratomatous TGCT but not in the peritoneal adenocarcinoma. Furthermore, NGS showed no mutations in the primary teratomatous TGCT but a KRAS and GNAS mutation in the peritoneal adenocarcinoma, suggestive of an appendicular origin.

Conclusions

Without the molecular data, both cases would have been regarded as a metastatic TGCT with development of somatic-type malignancy, which appeared a wrong diagnosis for case 2. These cases demonstrate the importance of molecular methods as an adjunct in today’s pathology practice.

Spontaneous regression as a 'burned-out' non-seminomatous testicular germ cell tumor: a case report and literature review

Testicular germ cell tumors (TGCTs) are the most frequent type of cancer in young adults. An exceptional event is the spontaneous regression (SR) of the primary tumor. Herein, we describe a burned-out non-seminomatous TGCT case and relevant literature review. A 34-year-old male presenting with low back pain was found to have a retroperitoneal mass upon urotomography. During workup, a heterogeneous testicular mass was evident, and its biopsy showed findings that support the diagnosis of spontaneous tumoral regression. The patient underwent unilateral orchiectomy and a chemotherapy protocol was later initiated, with 85% regression of the retroperitoneal metastatic mass. No progression of the primary tumor has been found. The etiology of SR across different cancer types appears to be associated with the host's immune response and an angiogenic disturbance of the tumor microenvironment. The burned-out phenomenon is a rare event that needs further research into its molecular sequencing.

Global DNA demethylation as an epigenetic marker of human brain metastases

Brain metastases are the most common intracranial tumors in adults. They usually originate from: lung, breast, renal cell and gastrointestinal cancers, as well as melanoma. Prognosis for brain metastases is still poor and classical treatment combining surgery and radiation therapy should be strongly supported with molecular approaches. However, their successful application depends on a deep understanding of not only genetic, but also epigenetic background of the disease. That will result in an earlier and more precise diagnosis, successful treatment, as well as individualized estimation of clinical outcomes and prognosis. It has already been shown that the epigenetic machinery plays a crucial role in cancer biology, development, and progression. Therefore, we decided to look for metastasis through changes in the most studied epigenetic mark, 5-methylcytosine (m⁵C) in DNA. We performed global analysis of the m⁵C contents in DNA isolated from the brain metastatic tumor tissue and peripheral blood samples of the same patients, using thin layer chromatography separation of radioactively labeled nucleotides. We found that the m⁵C level in DNA from brain metastases: changes in the broad range, overlaps with that of blood, and negatively correlates with the increasing tumor grade. Because the amount of m⁵C in tumor tissue and blood is almost identical, the genomic DNA methylation can be a useful marker for brain metastases detection and differentiation. Our research creates a scope for future studies on epigenetic mechanisms in neuro-oncology and can lead to development of new diagnostic methods in clinical practice.