Here, we present the case of a 70-year-old Caucasian male found to have clinically significant intraductal prostate carcinoma (IDC). The patient presented with a history of elevated PSA and benign prostatic hyperplasia, with no prior prostate biopsy. At the time, he took tadalafil for lower urinary tract symptoms and testosterone gel-based hormone replacement therapy (maintaining serum levels between 500 and 600 ng/dL for the past 17 years). His history was significant for a cardiac stent placement in 2021; his surgical history was noncontributory. He had no family history of prostate cancer or breast cancer. The patient is a former smoker and reported leading an active lifestyle, including regular exercise. Concerningly, the patient’s PSA levels increased from 2.04 ng/mL in September 2020 to 5.85 ng/mL at the time of presentation.

A multiparametric MRI revealed 2 significant lesions in the peripheral zone. Both were categorized as Prostate Imaging Reporting and Data System 5, indicating a very high likelihood of clinically significant prostate cancer. The largest of these lesions was found in the right base posterolateral peripheral zone of the prostate, measuring 16 × 24 × 16 mm with suspected extraprostatic extension (EPE) and extension into the transition zone (Figure 1). A minor lesion was in the left apex peripheral zone, measuring 8 × 15 × 16 mm with no EPE. Neither showed evidence of hemorrhage, invasion of the neurovascular bundle, seminal vesicle, pelvic adenopathy, or bone lesions.

Notably, unusual features were observed on ultrasound imaging during the biopsy: the lesions, visible as a hyper/isoechoic area, contained many diffusely distributed, hyperechoic spiculated areas (Figure 2). This differs from the typical presentation of prostate cancer, which is typically appreciated on ultrasound as a less heterogeneous, hypoechoic lesion (though up to 40% of lesions can be hyperechoic or isoechoic)¹; the hyperechoic foci found in our patient have not been previously described in the literature, and hemorrhage was not suspected given there was no hemorrhage appreciated on the MRI a few weeks earlier.

Magnetic resonance/ultrasound fusion-guided biopsy was performed for a definitive diagnosis; 7 of the 14 samples taken were positive for IDC, an unconventional histology generally associated with adverse outcomes. Additionally, 3 samples were positive for atypical intraductal proliferation and 1 for adenocarcinoma (Gleason score 5 + 4 = 9). The patient’s pretreatment prostate-specific membrane antigen positron emission tomography/CT was negative for metastatic disease, but the intraprostatic findings were also concordant with the multiparametric MRI of the prostate with a mild increase in radiotracer uptake (standardized uptake value, 3.8-5.8) with the larger volume lesion (right base) having diffuse uptake with a lower standardized uptake value (less uptake) compared the left apex. Based on these results, a radical prostatectomy was performed. Surgical pathology confirmed that IDC comprised the majority of the neoplastic tissue, with smaller adenocarcinoma components; immunohistochemistry confirmed this. EPE, which was appreciated on the MRI, was also confirmed. The surgical margins and 25 lymph nodes examined were negative for tumor.

The unusual hyperechoic regions visible on ultrasound could represent a novel imaging feature of IDC. Earlier detection of this unconventional and dangerous pathology through ultrasound imaging could inform the treatment of these cancers. Further examination of ultrasound findings in other IDC cases is warranted.