RESUMEN
INTRODUCTION: The metabolism of the body is a complicated process. The most important organ of the organism that affects the intensity of changes is the liver. An effective treatment method of primary and metastatic tumours is a partial resection of the organ. The analysis of changes in the body composition of patients undergoing this type of treatment allows identification of problems coexisting with the underlying disease. AIM: To evaluate changes in the parameters of body composition and the amount of resting metabolism. MATERIAL AND METHODS: The study group consisted of 87 patients who underwent resection of changes in the liver or thermoablation of focal lesions during hospitalisation. RESULTS: Analysis of the data showed that the surgical intervention contributes to a statistically significant (p < 0.05) decrease in the value of the phase angle. A significant increase was noted within the extra cellular water content. The amount of resting metabolism in the postoperative period did not differ significantly; however, there was an upward trend in women and a downward trend in men. CONCLUSIONS: Surgical resection of lesions aimed at extending the survival of patients are performed more and more often, while the consequences of these operations are not sufficiently known. The adverse effect of resection treatments on body composition parameters, mainly imaged by decreasing the phase angle value, should be minimised. Effects on metabolism remain ambiguous because no significant changes have been demonstrated in the postoperative period.