Photo Credit: Nemes Laszlo

The prognostic nutritional index (PNI) was linked to various survival metrics in endometrial cancer (EC), and may improve risk stratification in EC.

The prognostic nutritional index (PNI) is a non-invasive test that combines serum albumin concentration and total peripheral blood lymphocyte count. The results reflect a patient’s nutritional reserves, inflammatory status, and immune response. Studies have shown this test has prognostic value concerning cancer outcomes, and numerous research initiatives have explored its application to various cancers.

Endometrial cancer (EC), however, has received little attention regarding the application of PNI. To remedy this gap in knowledge, Jiarui Quin, MD, and colleagues developed a meta-analysis to confirm the value of PNI as a predictive tool for the survival outcomes of patients with EC. The study’s results were published in Reproductive Sciences.

PNI Linked to Overall Survival

After an extensive literature search, the researchers included 10 studies encompassing 3,656 women with EC in the meta-analysis. Each study selected provided a hazard ratio (HR) for overall survival (OS) and progression-free survival (PFS) as predicted by PNI levels.

A low PNI baseline in patients with EC was associated with a poor OS (HR, 2.01; 95% CI, 1.62–2.49, P<0.05; I²=54%). The results were not significantly altered when the researchers performed sensitivity analysis by removing one study at a time (HR, 1.90–2.06; P<0.05).

The country where each of the studies was conducted also did not significantly affect the conclusions of the analysis (P=0.65). The mean age of the patients in the cohort had little impact on the results (P=0.81).

There was a stronger correlation between low PNI and poor OS in studies that included patients with stage I-III EC compared with those with stage IV EC (HR, 2.78 vs 1.71; P=0.01). A meta-regression examination revealed the correlation between PNI and OS was not substantially affected by factors like sample size, mean age, PNI cut-off score, the occurrence of follow-up visits, or study quality scores (P>0.05).

Association With PFS

The researchers performed a meta-analysis of six studies to examine the correlation between PFS and baseline PNI. They observed a significant association between poor PFS and low PNI at baseline (HR, 2.75; 95% CI, 1.74–4.33; P<0.05; I²=78%). In addition, the authors found comparable results during sensitivity analysis (HR, 2.30–3.17; P<0.05).

The country where each of the studies was conducted did not significantly affect the analysis’s conclusions (P=0.97). The mean age of the patients also had little impact on the results (P=0.26).

The inclusion of stage IV patients (P=0.83), the cutoff score for PNI (P =0.26), and the occurrence of follow-up durations (P=0.62) did not substantially affect the correlation between PNI and PFS.

“The findings support the use of PNI as a valuable prognostic marker in clinical practice, aiding in the identification of high-risk patients who may benefit from more intensive monitoring and therapeutic interventions,” Dr. Qin and colleagues concluded.

Supporting Results

An analysis developed by Qing Zhang, MD, and colleagues that focused on the prognostic value of PNI in cervical, ovarian, and endometrial cancer found similar results. The findings were published in BMC Women’s Health. In this study, 28 articles were included in the meta-analysis with 9,428 patient participants. The researchers found that low PNI correlated with poor OS (HR, 1.60; 95% CI, 1.39–1.84; P<0.001), PFS (HR, 1.63; 95% CI, 1.20–2.23; P=0.002), and disease-free survival (HR, 1.73; 95% CI, 1.19–2.52; P=0.004). The only cancer studied that did not show PNI as having a prognostic value in terms of OS was cervical cancer. A low PNI was observed to be significantly associated with International Federation of Gynecology and Obstetrics stages III to IV (OR, 2.30; 95% CI, 1.89‒2.80; P<0.001) and lymph node metastasis (OR, 2.76; 95% CI, 2. 05‒3.73; P<0.001).