Cancer is a chronic disease that, due to its natural progression and/or treatment, is frequently accompanied by electrolyte disturbances. These disturbances are associated with increased mortality, longer hospital stays, and higher healthcare costs in cancer patients [1].

Several studies have been conducted on the mechanisms underlying these disorders and their impact on overall survival and mortality in oncology [2]-[4]. However, there are few studies on the prevalence of these electrolyte disorders in cancer patients, particularly in sub-Saharan Africa.

In this study, our objective was to determine the prevalence of electrolyte disorders in hospitalized cancer patients.

During the study period, we included 160 patients who met the criteria. Sociodemographic and clinical characteristics are reported in Table 1.

Among the patients included in the study, 80.6% (n = 129) had at least one electrolyte disorder. Hyponatremia was the most common disorder, present in 51.5% of patients, followed by hypokalemia, hypochloremia, and hyperkalemia, with prevalences of 36.5%, 28.1%, and 15.6%, respectively. Table 2 details the prevalence of each disorder according to the organ affected.

Table 1. Sociodemographic and clinical characteristics.

Table 2. Prevalence of disorders according to cancer site.

In our study, the prevalence of electrolyte disturbances was 80.6%. This high prevalence could be explained, on the one hand, by the predominance of advanced stages (locally advanced and metastatic), which accounted for 88.8% of cases in our study, and, on the other hand, by the high proportion of elderly people, with 42.5% of patients aged over 60.

Among the most common disorders are hyponatremia and hypokalemia, which were more pronounced in cancers of the upper digestive tract and were related to stenosis in these organs, a consequence of the advanced stage. Similarly, hyperkalemia was more pronounced in cancers of the uterus, and the mechanism most often found in the literature was compression of the urinary tract, causing acute obstructive renal failure [5]-[7].

An overall prevalence of 58% was found in a study in China, however, the study included a small proportion of patients with metastases (7.6%) [1]. Similarly, Bharti et al. reported a prevalence of 42% in India [8].

Hyponatremia was the most common disorder with a prevalence of 51.5%. Syndrome of inappropriate ADH secretion (SIADH) is the main cause of hyponatremia in cancer patients, particularly those with lung cancer [9][10]. Water-sodium depletion is also a major cause of hyponatremia; it is most often secondary to digestive losses, particularly in gastrointestinal tumors [9].

Hypokalemia was found in 36.5% of patients. Several etiologies are responsible for hypokalemia in oncology, including intake deficiencies (malnutrition, anorexia, etc.) and digestive losses [11]. Hypokalemia may also be linked to inappropriate refeeding syndrome [12]. Hypochloremia was found in 28.1% of patients; it is mainly due to digestive losses [13].

Hyperkalemia was found in 16.5% of patients. Tumor lysis syndrome is the main cause of hyperkalemia in oncology; it can occur spontaneously or after the initiation of chemotherapy [14]. Hyperchloremia was found in 16.2% of cases. It is mainly iatrogenic in origin, due to the chlorine content of the replacement fluids [15]. Hypernatremia was found with a prevalence of 1.2%. It may be related to free water loss. It may also be iatrogenic [16].

Limitations of the study: this was a retrospective, single-center study with a small sample size.

This study highlighted a high prevalence of electrolyte disturbances in oncology. We therefore recommend systematic monitoring of electrolytes in high-risk patient groups, such as those with upper gastrointestinal tract cancers and prophylactic urinary diversion, particularly through the placement of a double J stent in advanced uterine cancers. Future studies should investigate the impact of electrolyte disturbances on length of hospital stay, initiation of anticancer treatment, and mortality in our regions.