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Advances in Radiotherapy
& Nuclear Medicine LuPSMA response patterns on PSMA PET

A

B

Figure 3. Kaplan-Meier curves for OS according to: (A) TLW response category. “Responders” had a significantly lower hazard of death compared with
“low-volume progressors” and “high-volume progressors.” (B) RECIP 1.0 category. Participants with RECIP-PR had a significantly lower hazard of death
compared to those with RECIP-PD.
Abbreviations: mo: Months; OS: Overall survival; RECIP: Response evaluation criteria in PSMA PET; RECIP-PD: Response evaluation criteria in PSMA-
progressive disease; RECIP-PR: Response evaluation criteria in PSMA-partial response; RECIP-SD: Response evaluation criteria in PSMA-stable disease.

TLW “responders” were found to have a significant Post-treatment imaging showed that 61% of TLW
reduction in SUV max and SUV mean on post-treatment “progressors” (17/28) had an SUV >15 (exceeding the
max
imaging. SUV reduced to a median of 7.8 (range 1.6– trial entry threshold), whereas none of the “responders”
max
12.5) from a baseline median of 37.8 (range 5–122), and (0/9) had a persistently high SUV . This finding suggests
max
SUV mean reduced to a median of 3.7 (range 0.9–5.4) from that treatment failure was more often associated with
8.5 (range 3.9–12) (Table 2). persistent PSMA avidity at disease sites rather than an
Furthermore, the mean difference between SUV and inadequate response due to low PSMA expression (Table 2).
max
SUV mean narrowed significantly in “responders” (from 28 to In addition, TLW analysis facilitated the identification of
4), whereas it widened in “progressors” (from 14 to 20), patients exhibiting oligo-progression (defined as fewer than
indicating greater heterogeneity of PSMA expression in five new or enlarging lesions), as well as those with disease
the TLW “progressors” (Figure 4). progression characterized by low PSMA expression (Figure 5).

Volume 3 Issue 3 (2025) 48 doi: 10.36922/ARNM025110011