Correlation of the Neutrophil-to-lymphocyte and Platelet-to-lymphocyte Ratios with Postoperative Complications and Survival in Surgery for Bone Metastasis of the Appendicular Skeleton

TL;DR

This study finds that higher neutrophil-to-lymphocyte and platelet-to-lymphocyte ratios are linked to shorter survival in patients undergoing surgery for bone metastases, though not to postoperative complications.

Contribution

The study identifies a novel correlation between elevated NLR and PLR levels and reduced survival in patients with bone metastases.

Findings

Patients with NLR ≥ 2 had a significant decrease in survival rates from 92.3% to 62.5% by the third month.

PLR ≥ 209 was associated with a decline in survival from 69% to 59.3% in the third month.

Higher neutrophil levels correlated with a 1% increased risk of postoperative complications per 100 neutrophils.

Abstract

Objective
 To analyze, in cases of long-bone metastases, the incidence of postoperative complications and survival of up to 1 year, correlating them with the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR).

Methods
 Review of 160 medical records of patients who underwent surgery for bone metastases in the appendicular skeleton. We determined epidemiological characteristics and NLR and PLR values, which were correlated with survival and complications.

Results
 Women represented 64.5% of the sample, and 62.6% presented primary breast tumor. The proximal femur was the most affected bone. The median survival was of 13.2 months, and the 1-year survival rate, of 34.7%. Tumor resection with endoprosthesis was the most common surgery. The postoperative complication rate was of 10%, and the mean time until occurrence was of 27.9 (range: 0–140) days. We observed a significant association between neutrophil levels and postoperative complications (
p
 = 0.04): for every increase of 100 neutrophils, the risk of postoperative complications increased by 1%. The mean NLR and PLR values were of 5.3 (range: 0.2–30.7) and 199.7 (range: 32.1–676.7) respectively. Patients with NLR ≥ 2 (
p
 < 0,001) showed a decrease in survival from 92,3 to 62,5% in the third month, and from 61,5 to 31,3% in the first year. Those with PLR ≥ 209 (
p
 < 0.001) showed a decrease in survival from 69 to 59.3% in the third month, and from 40.2 to 25.9% in the first year.

Conclusion
 There was no positive association regarding the NLR and PLR and postoperative complications. However, we noted a strong correlation involving elevated NLR and PLR levels and reduced life expectancy starting from the third postoperative month.

Objetivo
 Analisar, em metástases de ossos longos, a incidência de complicações e sobrevida pós-operatórias até um ano, e correlacioná-las com a razão neutrófilo-linfócito (RNL) e a razão plaqueta-linfócito (RPL).

Métodos
 Revisão de 160 prontuários de pacientes submetidos a cirurgias por metástases ósseas no esqueleto apendicular. Além das características epidemiológicas, foram determinados os valores da RNL e da RPL, que foram correlacionados com sobrevida e complicações.

Resultados
 Mulheres representaram 64,5% da amostra, com tumor primário na mama em 62,6%. O fêmur proximal foi o osso mais acometido. A sobrevida média foi de 13,2 meses, e a taxa de sobrevida em 1 ano, de 34,7%. Ressecção tumoral com endoprótese foi o procedimento mais comum. A taxa de complicação pós-operatória foi de 10%, e o tempo médio para a ocorrência de complicações pós-operatórias foi de 27,9 (variação: 0–140) dias. Foi identificada uma associação da variável neutrófilos com as complicações pós-operatórias (
p
 = 0,04): a cada 100 unidades a mais de neutrófilos, houve aumento de 1% nas chances de complicações pós-cirúrgicas. Os valores médios da RNL e da RPL foram, respectivamente, de 5,3 (variação: 0,2–30,7) e de 199,7 (variação: 32,1–676,7). Os pacientes com RNL ≥ 2 (
p
 < 0,001) apresentaram diminuição na sobrevida de 92,3 para 62,5% no terceiro mês, e de 61,5 para 31,3% em 1 ano. Aqueles com RPL ≥ 209 (
p
 < 0,001) apresentaram diminuição na sobrevida de 69 para 59,3% no terceiro mês, e de 40,2 para 25,9% em 1 ano.

Conclusão
 Não houve associação positiva entre RNL e RPL com complicações pós-operatórias, mas houve uma forte correlação da RNL e da RPL elevadas com a redução da expectativa de vida dos pacientes a partir do terceiro mês de pós-operatório.

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