Serum Levels of MicroRNA-371a-3p for Predicting the Histology of Postchemotherapy Residual Masses of Germ Cell Tumours.

BACKGROUND AND OBJECTIVE: Serum levels of microRNA-371a-3p (M371) represent a novel and sensitive biomarker of germ cell tumours (GCTs). This study analysed the utility of M371 to identify viable cancer (VC) in postchemotherapy (pc) residual masses with the underlying goal of avoiding overtreatment. METHODS: A multicentric, prospective diagnostic study was conducted in 180 GCT patients undergoing pc resection of residual masses. A correlation of M371 measurement results with the histological presence of VC in masses was found. A receiver operating characteristic analysis was performed for exploring the performance characteristics of the test. KEY FINDINGS AND LIMITATIONS: The sensitivity was found to be 68.9%, specificity 99.3%, area under the curve 0.813, positive predictive value 0.969, and negative predictive value 0.905; sensitivity is significantly associated with the percentage of VC in the mass. In specimens with ≤10% VC, there were 33.3% elevated M371 levels as opposed to 85.7% in specimens with >50% VC. Teratoma and somatic-type malignancy do not express M371. A lack of a central pathological review is a limitation. CONCLUSIONS AND CLINICAL IMPLICATIONS: The M371 test can identify 68.9% of patients with VC in pc masses. However, cases with <10% VC in the mass may escape detection. Teratoma does not express M371. The test alone cannot correctly identify patients requiring pc surgery, but it may be a tool for scheduling the extent of surgery. PATIENT SUMMARY: The microRNA-371a-3p (M371) test can identify about two-thirds of patients with viable cancer in residual metastatic masses following chemotherapy for germ cell tumours. Only masses with high percentages of viable cancer cells can be identified, and the histological subtype teratoma remains undetected with the test.

Testicular neoplasms: the interrelationships of serum levels of microRNA-371a-3p (M371) and classical tumor markers with histology, clinical staging, and age-a statistical analysis.

PURPOSE: In testicular neoplasms, the interrelationship of elevations of the novel serum tumor marker microRNA-371a-3p (M371) and traditional markers with other clinical features is still incompletely understood. The present study evaluated marker expression rates in relation to various other clinical parameters. METHODS: The following data were retrospectively registered from 641 consecutive patients with testicular neoplasms: histology, such as seminoma (n = 365), nonseminoma (n = 179), benign tumor (n = 79), other malignant tumor (n = 18); patients age (years); clinical stage (CS1, CS2a/b, CS2c, CS3); and preoperative elevation of beta HCG, AFP, LDH, M371 (yes/no). Descriptive statistical methods were employed with comparisons of various subgroups to disclose associations of marker expression rates with age, histology and CS, and of age with histology. RESULTS: The histologic subgroups revealed significantly different expression rates of tumor markers. M371 performed best with expression rates of 82.69% and 93.58% in seminoma and in nonseminoma, respectively. In germ cell tumors, all markers had significantly higher expression rates in metastasized stages than in localized disease. All markers except LDH have significantly higher expression rates in younger than in older patients. Nonseminoma is most prevalent in the youngest age category, seminoma predominates in patients > 40 years, other malignancies were restricted to patients > 50 years. CONCLUSION: The study documented significant associations of serum marker expression rates with histology, age and clinical staging, with highest rates in nonseminomas, young age and advanced clinical stages. M371 showed significantly higher expression rates than other markers suggesting its superior clinical usefulness.

Serum Levels of MicroRNA-371a-3p (M371) Can Predict Absence or Presence of Vital Disease in Residual Masses After Chemotherapy of Metastatic Seminoma.

Background: Radiological evaluation of postchemotherapy residual masses of metastatic seminoma is characterized by poor diagnostic accuracy. Serum levels of microRNA-371a-3p (M371) involve high specificity and sensitivity for the primary diagnosis of seminoma. We evaluated if M371 levels can indicate the presence of vital disease in postchemotherapy residual masses in patients with metastatic seminoma. Methods: Twenty-three seminoma patients (median age 52 years) with residual masses had posttreatment measurements of serum M371 levels (group A), fourteen of whom had measurements also beforehand. The posttreatment results were compared with the clinical outcome during follow-up. Eleven patients with complete remission after treatment of metastatic seminoma (group B) and 33 men with non-malignant testicular diseases (group C) served as controls. M371 serum levels were measured by quantitative real-time PCR using miR-30b-5p as endogenous control. An evaluation was performed with descriptive statistical methods. Results: Twenty-two patients of Group A had uneventful follow-up so far, twenty-one of whom had M371 level <5, and one other had a mildly elevated level below relative quantity (RQ) = 10. One patient with a level of RQ = 26.2 rapidly progressed. The median posttreatment M371 level of the non-progressing patients of group A is not significantly different from the median level of the control group with complete remission (B). Before treatment, the median M371 levels in groups A and B were 507.6 and 143.9, respectively. In both groups, significant drops in M371 levels resulted from treatment. Conclusion: Normal M371 serum levels at the time of completion of treatment of metastatic seminoma indicate the absence of vital seminoma in residual masses, while elevated levels >RQ = 10 predict the presence of disease. The optimal timing of M371 measurement after chemotherapy and the appropriate cutoff level still need to be determined. Based on the present results, measuring serum M371 levels involves the potential of a novel tool for assessing postchemotherapy residual masses of metastatic seminoma.

Testicular Neoplasms: Primary Tumour Size Is Closely Interrelated with Histology, Clinical Staging, and Tumour Marker Expression Rates-A Comprehensive Statistical Analysis.

The role of primary tumour size (TS) in the clinical course of testicular tumours is incompletely understood. We retrospectively evaluated 641 consecutive patients with testicular neoplasms with regard to TS, histology, clinical stage (CS), serum tumour marker (STM) expression and patient age using descriptive statistical methods. TS ≤ 10 mm was encountered in 13.6% of cases. Median TS of 10 mm, 30 mm, 35 mm, and 53 mm were found in benign tumours, seminomas, nonseminomas, and other malignant tumours, respectively. In cases with TS ≤ 10 mm, 50.6% had benign tumours. Upon receiver operating characteristics analysis, TS of > 16 mm revealed 81.5% sensitivity and 81.0% specificity for detecting malignancy. In subcentimeter germ cell tumours (GCTs), 97.7% of cases had CS1, and CS1 frequency dropped with increasing TS. Expression rates of all STMs significantly increased with TS. MicroRNA-371a-3p (M371) serum levels had higher expression rates than classical STMs, with a rate of 44.1% in subcentimeter GCTs. In all, TS is a biologically relevant factor owing to its significant associations with CS, STM expression rates and histology. Importantly, 50% of subcentimeter testicular neoplasms are of benign nature, and M371 outperforms the classical markers even in subcentimeter tumours.

Serum levels of microRNA-371a-3p are not elevated in testicular tumours of non-germ cell origin.

PURPOSE: Serum levels of microRNA-371a-3p (M371) have been shown to be a highly sensitive and specific biomarker for testicular germ cell tumours (TGCT). Little information exists on the expression of this marker in testicular neoplasms deriving from the gonadal stroma or other structures of the gonad. This study presents an expression analysis of the novel TGCT-biomarker M371 in a large cohort of testicular non-germ cell tumours. METHODS: The M371 expression was measured by quantitative real time PCR in serum of 99 patients with testicular tumours of non-germ cell origin, thereof 30 patients with malignant testicular lymphomas and 61 patients with gonadal stroma tumours such as Leydig cell tumours, Sertoli cell tumours and 8 cases with miscellaneous benign testicular tumours. Their M371 levels were compared to those of 20 patients with TGCT and to 37 tumour-free male controls. RESULTS: The median expression levels of benign testicular tumours and testicular lymphoma are close to zero, thus, identical with those of controls and significantly lower than those of TGCT. In summary, this study provides further evidence for the notion that M371 is exclusively expressed by germ cell tumours and not by testicular neoplasms of the non-germ cell subtypes. CONCLUSION: Clinically, the test might be of value in preoperative characterization of benign testicular tumours eligible for conservative surgery.

Serum Level of microRNA-375-3p Is Not a Reliable Biomarker of Teratoma.

BACKGROUND/AIM: Clinical management of testicular germ cell tumours (GCT) is based upon the measurement of serum tumour markers. Recent studies have shown that the microRNA-371a-3p is a sensitive and specific serum biomarker for all subgroups of GCT, except teratoma. To close the diagnostic gap relating to teratoma, serum levels of microRNA-375-3p have recently been suggested to represent a specific serum marker of this histological subgroup. In the present study, we tested this hypothesis. MATERIALS AND METHODS: miRNA expression was analysed in serum of 21 GCT patients with teratoma, twelve patients with other GCT, and twelve male controls using the qPCR method. RESULTS: The serum miR-375-3p levels of teratoma patients were not different from other GCT patients or controls. The ROC analysis revealed an AUC of 0.524 for the discrimination between teratoma and other pathologies. CONCLUSION: The miR-375-3p does probably not qualify for a useful serum biomarker to distinguish teratoma from other GCTs and from controls.

Graded expression of microRNA-371a-3p in tumor tissues, contralateral testes, and in serum of patients with testicular germ cell tumor.

Background: Serum levels of microRNA-371a-3p represent a specific tumor marker of testicular germ cell tumors (GCTs) but the origin of circulating miR-371a-3p is not finally resolved. The correlation between miR-levels in tissue and serum is unclear. Results: MiR-levels in GCT tissue are 399-fold higher than in contralateral testicular tissue and 5843-fold higher than in non-testicular tissue. MiR tissue levels correlate with corresponding serum levels (r 2 = 0.181). ISH detected miR-371a-3p intracellularly in GCT cells except teratoma. A low expression was also detected in normal testicular germ cells. Conclusions: Circulating miR-371a-3p is specifically derived from GCT tissue. The miR is present in GCT cells except teratoma. A low expression is also found in normal testicular tissue but not in non-testicular tissue. MiR-371a-3p levels in tissue and serum correlate significantly. This study underscores the usefulness of serum miR-371a-3p as tumor marker of GCT. Patients and methods: Expression levels of miR-371a-3p were concurrently measured in tissues of GCT, contralateral testes ( n = 38), and in serum ( n = 36) with real time PCR. For control, 5 healthy testicles and 4 non-testicular tissue samples were examined. MiR-levels were compared using descriptive statistical methods. We also performed in situ hybridization (ISH) of GCT tissue with a probe specific for miR-371a-3p.