Impact of differing methodologies for serum miRNA-371a-3p assessment in stage I testicular germ cell cancer recurrence

INTRODUCTION Current evidence shows that serum miR-371a-3p can identify disease recurrence in testicular germ cell tumour (TGCT) patients and correlates with tumour load. Despite convincing evidence showing the advantages of including miR-371a-3p testing to complement and overcome the classical serum tumour markers limitations, the successful introduction of a serum miRNA based test into clinical practice has been impeded by a lack of consensus regarding optimal methodologies and lack of a universal protocol and thresholds. Herein, we investigate two quantitative real-time PCR (qRT-PCR) based pipelines in detecting disease recurrence in stage I TGCT patients under active surveillance, and compare the sensitivity and specificity for each method. METHODS Sequential serum samples collected from 33 stage I TGCT patients undergoing active surveillance were analysed for miR-371a-3p via qRT-PCR with and without an amplification step included. RESULTS Using a pre-amplified protocol, all known recurrences were detected via elevated miR-371a-3p expression, while without pre-amplification, we failed to detect recurrence in 3/10 known recurrence patients. For pre-amplified analysis, sensitivity and specificity was 90% and 94.4% respectively. Without amplification, sensitivity dropped to 60%, but exhibited 100% specificity. DISCUSSION We conclude that incorporating pre-amplification increases sensitivity of miR-371a-3p detection, but produces more false positive results. The ideal protocol for quantification of miR-371a-3p still needs to be determined. TGCT patients undergoing active surveillance may benefit from serum miR-371a-3p quantification with earlier detection of recurrences compared to current standard methods. However, larger cross-institutional studies where samples are processed and data is analysed in a standardised manner are required prior to its routine clinical implementation

Impact of differing methodologies for serum miRNA-371a-3p assessment in stage I testicular germ cell cancer recurrence.

INTRODUCTION Current evidence shows that serum miR-371a-3p can identify disease recurrence in testicular germ cell tumour (TGCT) patients and correlates with tumour load. Despite convincing evidence showing the advantages of including miR-371a-3p testing to complement and overcome the classical serum tumour markers limitations, the successful introduction of a serum miRNA based test into clinical practice has been impeded by a lack of consensus regarding optimal methodologies and lack of a universal protocol and thresholds. Herein, we investigate two quantitative real-time PCR (qRT-PCR) based pipelines in detecting disease recurrence in stage I TGCT patients under active surveillance, and compare the sensitivity and specificity for each method. METHODS Sequential serum samples collected from 33 stage I TGCT patients undergoing active surveillance were analysed for miR-371a-3p via qRT-PCR with and without an amplification step included. RESULTS Using a pre-amplified protocol, all known recurrences were detected via elevated miR-371a-3p expression, while without pre-amplification, we failed to detect recurrence in 3/10 known recurrence patients. For pre-amplified analysis, sensitivity and specificity was 90% and 94.4% respectively. Without amplification, sensitivity dropped to 60%, but exhibited 100% specificity. DISCUSSION We conclude that incorporating pre-amplification increases sensitivity of miR-371a-3p detection, but produces more false positive results. The ideal protocol for quantification of miR-371a-3p still needs to be determined. TGCT patients undergoing active surveillance may benefit from serum miR-371a-3p quantification with earlier detection of recurrences compared to current standard methods. However, larger cross-institutional studies where samples are processed and data is analysed in a standardised manner are required prior to its routine clinical implementation

Detection of recurrences using serum miR-371a-3p during active surveillance in men with stage I testicular germ cell tumours.

BACKGROUND MiR-371a-3p predicts the presence of a macroscopic non-teratomatous germ cell tumour (GCT). We hypothesised that miR-371a-3p can also detect recurrence during active surveillance (AS) of stage I GCT. METHODS We prospectively collected serum samples of 33 men. Relative expression of serum miR-371a-3p levels was determined at each follow-up visit using real-time quantitative reverse transcription-polymerase chain reaction. RESULTS Recurrence was detected using standard follow-up investigations in 10/33 patients (30%) after a median of 7 months. Directly after orchiectomy, miR-371a-3p levels were not elevated in any of the 15 patients with available post-orchiectomy samples. However, all ten recurring patients exhibited increasing miR-371a-3p levels during follow-up, while miR-371a-3p levels remained non-elevated in all but one patient without recurrence. MiR-371a-3p detected recurrences at a median of 2 months (range 0-5) earlier than standard follow-up investigations. CONCLUSIONS MiR-371a-3p levels immediately post orchiectomy are not predictive for recurrences and unfortunately cannot support decision-making for AS vs. adjuvant treatment. However, miR-371a-3p detects recurrences reliably and earlier than standard follow-up investigations. If this can be confirmed in larger cohorts, monitoring miR-371a-3p could replace surveillance imaging in seminomatous GCT and reduce the amount of imaging in non-seminomatous GCT. Earlier detection of disease recurrence may also reduce the overall treatment burden

DataSheet_1_Impact of differing methodologies for serum miRNA-371a-3p assessment in stage I testicular germ cell cancer recurrence.docx

IntroductionCurrent evidence shows that serum miR-371a-3p can identify disease recurrence in testicular germ cell tumour (TGCT) patients and correlates with tumour load. Despite convincing evidence showing the advantages of including miR-371a-3p testing to complement and overcome the classical serum tumour markers limitations, the successful introduction of a serum miRNA based test into clinical practice has been impeded by a lack of consensus regarding optimal methodologies and lack of a universal protocol and thresholds. Herein, we investigate two quantitative real-time PCR (qRT-PCR) based pipelines in detecting disease recurrence in stage I TGCT patients under active surveillance, and compare the sensitivity and specificity for each method.MethodsSequential serum samples collected from 33 stage I TGCT patients undergoing active surveillance were analysed for miR-371a-3p via qRT-PCR with and without an amplification step included.ResultsUsing a pre-amplified protocol, all known recurrences were detected via elevated miR-371a-3p expression, while without pre-amplification, we failed to detect recurrence in 3/10 known recurrence patients. For pre-amplified analysis, sensitivity and specificity was 90% and 94.4% respectively. Without amplification, sensitivity dropped to 60%, but exhibited 100% specificity.DiscussionWe conclude that incorporating pre-amplification increases sensitivity of miR-371a-3p detection, but produces more false positive results. The ideal protocol for quantification of miR-371a-3p still needs to be determined. TGCT patients undergoing active surveillance may benefit from serum miR-371a-3p quantification with earlier detection of recurrences compared to current standard methods. However, larger cross-institutional studies where samples are processed and data is analysed in a standardised manner are required prior to its routine clinical implementation.</p