PSMA PET-CT in patients with high-risk PCa before curative-intent surgery or radiotherapy ...

[pjoshea13]

New study below [1].

From MedPage Today article [2]:

"In men with high-risk prostate cancer, imaging with prostate-specific membrane antigen (PSMA) PET-CT prior to curative surgery or radiotherapy proved far more accurate than conventional imaging for detecting metastatic disease, a randomized trial found.

"Among 295 evaluable patients, gallium-68 PSMA-11 PET-CT imaging had an accuracy of 92% (area under the curve [AUC] of the receiver operating characteristic curve) versus 65% with standard CT imaging and bone scans ..."

"There were fewer equivocal cases of metastatic disease with PSMA PET/CT (7% vs 23% with conventional imaging), and the novel imaging method altered the course of disease management for twice as many men following first-line imaging (28% vs 15%, P=0.008). In those who underwent second-line imaging -- for men with no more than two unequivocal metastases -- change in treatment occurred in 27% of those that crossed over to PSMA PET/CT, but just 5% of those switching to conventional imaging."

-Patrick

[1] thelancet.com/journals/lanc...

Findings

From March 22, 2017 to Nov 02, 2018, 339 men were assessed for eligibility and 302 men were randomly assigned. 152 (50%) men were randomly assigned to conventional imaging and 150 (50%) to PSMA PET-CT. Of 295 (98%) men with follow-up, 87 (30%) had pelvic nodal or distant metastatic disease. PSMA PET-CT had a 27% (95% CI 23–31) greater accuracy than that of conventional imaging (92% [88–95] vs 65% [60–69]; p<0·0001). We found a lower sensitivity (38% [24–52] vs 85% [74–96]) and specificity (91% [85–97] vs 98% [95–100]) for conventional imaging compared with PSMA PET-CT. Subgroup analyses also showed the superiority of PSMA PET-CT (area under the curve of the receiver operating characteristic curve 91% vs 59% [32% absolute difference; 28–35] for patients with pelvic nodal metastases, and 95% vs 74% [22% absolute difference; 18–26] for patients with distant metastases). First-line conventional imaging conferred management change less frequently (23 [15%] men [10–22] vs 41 [28%] men [21–36]; p=0·008) and had more equivocal findings (23% [17–31] vs 7% [4–13]) than PSMA PET-CT did. Radiation exposure was 10·9 mSv (95% CI 9·8–12·0) higher for conventional imaging than for PSMA PET-CT (19·2 mSv vs 8·4 mSv; p<0·001). We found high reporter agreement for PSMA PET-CT (κ=0·87 for nodal and κ=0·88 for distant metastases). In patients who underwent second-line image, management change occurred in seven (5%) of 136 patients following conventional imaging, and in 39 (27%) of 146 following PSMA PET-CT.

[2] medpagetoday.com/hematology...