Background: Early identification of bacteremia in immunosuppressed cancer patients remains difficult, especially in neutropenia. This study evaluated the diagnostic accuracy of NLR, PLR, and NLPR for identifying bacteremia and sepsis in patients undergoing blood culture episode. Methods: We conducted a retrospective diagnostic accuracy study at a tertiary oncology center between January 2023 and December 2024. All bacteremia identified were included as cases. Culture-negative episodes were subsequently sampled as controls using a frequency-matching strategy. Hematological parameters were obtained within ±24 h of first blood culture episode. Diagnostic performance was assessed using ROC curve analysis and multivariable logistic regression. Results: Of 369 screened episodes, 337 from 323 unique patients were included after excluding 31 records. NLPR showed the highest accuracy for bacteremia (AUC 0.730; 95% CI 0.671–0.788). The optimal cut-off was 0.038 (sensitivity 69.2%, specificity 72.3%) and remained consistent after excluding episodes with antibiotic therapy (AUC 0.768), corticosteroids (AUC 0.708), or growth factor use (AUC 0.718). In severe neutropenia, NLPR showed the highest accuracy (AUC 0.887; 95% CI 0.797–0.978). In multivariable analysis (n = 304), NLPR remained independently associated with bacteremia (p < 0.001), with good model discrimination (AUC 0.815; 95% CI 0.763–0.866). Diagnostic performance for sepsis was lower and not statistically significant. Conclusions: These findings suggest that NLPR may represent a simple, inexpensive, widely accessible adjunctive biomarker to support early bacteremia risk stratification in immunosuppressed cancer patients, particularly in patients with severe neutropenia. Although its overall discrimination was comparable to isolated lymphocyte count, NLPR may provide clinically relevant contextual information by integrating multiple dimensions of immune dysregulation. Further prospective multicenter validation is warranted.

Background: Cancer-related pain involves complex peripheral and central mechanisms. Quantitative sensory testing (QST) assesses somatosensory function and provides insights into pain mechanisms. However, longitudinal evidence in oncological populations remains limited. This study investigated longitudinal changes in somatosensory function and their relationship with pain intensity and pain trajectory groups in a Portuguese cancer cohort. Methods: This longitudinal study was conducted within the international PAINLESS project and included participants from the Portuguese clinical unit. A total of 56 cancer patients were assessed at diagnosis (baseline, T0), before treatment, and at 6-month follow-up (T6). Pain intensity was measured using the Numeric Rating Scale (NRS), and somatosensory function was assessed using standardized thermal QST, including heat pain threshold (HPT), cold detection threshold (CDT), cold pain threshold (CPT), temporal summation of pain (TSP), and conditioned pain modulation (CPM). Non-parametric analyses evaluated longitudinal changes, correlations between pain and QST measures, differences according to clinically relevant pain (NRS < 4 vs. ≥ 4), and differences across clinically meaningful pain trajectory groups. Results: Thermal sensory thresholds changed significantly, with decreased HPT (p = 0.025) and increased CDT (p < 0.001) and CPT (p = 0.005). At T0, pain intensity was negatively correlated with CDT (r_s = − 0.371, p = 0.009), whereas at T6 it was positively correlated with CPT (r_s = 0.401, p = 0.006). Longitudinal changes in pain intensity were also associated with changes in CPT (r_s = 0.337, p = 0.029). Trajectory analysis demonstrated significant baseline CDT differences across pain trajectory groups (p = 0.028), with higher CDT values in the pain increase group than in the persistent pain group (adjusted p = 0.035). No significant longitudinal changes were observed in central pain modulatory measures (TSP and CPM). Conclusions: Altered thermal sensory processing, particularly cold-related measures, was associated with pain intensity and trajectories during the first six months after diagnosis. While central pain modulation remained stable, CDT and CPT showed consistent relationships with clinically relevant pain outcomes. These findings support the potential utility of thermal QST for characterizing sensory profiles and pain trajectory groups in cancer-related pain; being important, further longitudinal studies are needed to determine the predictive value of these measures.