Cognitive Fusion-Guided Transperineal Biopsy Leading to the Diagnosis of Early Prostate Adenocarcinoma After Repeated Negative Evaluations: A Case Report.

BACKGROUND: Prostate cancer remains one of the most frequently diagnosed malignancies in men, where early detection is key to curative treatment. Conventional biopsy techniques can miss small or focal lesions, especially in cases with persistently elevated prostate-specific antigen (PSA) levels and uncertain imaging, risking delayed diagnosis. CASE REPORT: We present the case of a 69-year-old male who initially presented in 2022 with lower urinary tract symptoms and an elevated PSA level of 26.17ng/ml. He was diagnosed with acute prostatitis and responded favourably to targeted treatment. Over the following two years, his PSA levels remained in the "gray zone" (7.24-8.68ng/ml), raising continued clinical suspicion despite normal findings on digital rectal examination (DRE), PIRADS 3 lesions on serial multiparametric magnetic resonance imaging (mpMRI), and two previous transperineal prostate biopsies, including a saturation biopsy-both with benign histopathology. In July 2025, the patient presented for the first time to our center. A new mpMRI again showed a PIRADS 3 lesion in the transitional zone of the right prostatic lobe. Given the persistent suspicion and previous negative results, a transperineal cognitive fusion-guided biopsy was performed, combining MRI-targeted and systematic sampling. Histopathological evaluation identified a 0.55 mm focus of acinar adenocarcinoma with a Gleason score of 7 (3+4). CONCLUSION: This case illustrates how cognitive fusion-guided biopsy can detect clinically significant prostate cancer in patients who have undergone prior negative standard biopsies. The technique improves diagnostic detection rates and represents a valuable, accessible alternative for centers without computer-assisted fusion platforms.