Focus on Renal Morphology, Chronic Kidney Disease, and Urinary System Malignancies in Acromegaly: Report on Data Collected Over a 40-year Period

Purpose While the cardiovascular and metabolic morbidities of acromegaly are well-established, data regarding long-term morphological and functional renal changes remain limited. This study evaluates the prevalence and independent predictors of renal cysts and chronic kidney disease (CKD), and additionally examines the frequency of urinary system malignancies relative to the general population in a large acromegaly cohort. Methods We retrospectively evaluated medical records, radiological findings, and clinical parameters of 394 patients with acromegaly monitored at a single tertiary center over four decades. Independent predictors of renal cysts and CKD were assessed using multivariate logistic regression. Standardized incidence ratios (SIRs) for urinary system cancers were calculated using Turkish population data as the reference. Results The cohort (202 male, 192 female) had a median disease duration of 17 years. Renal cysts were detected in 41% of patients, of which 47.4% were bilateral. CKD and nephrolithiasis were present in 16.1% and 15.1% of patients, respectively; notably, nearly two-thirds (64.9%) of CKD patients had preserved eGFR, with CKD diagnosed on the basis of albuminuria or structural abnormalities. Multivariate regression identified advanced age, nephrolithiasis, liver cysts, and multiple neoplasms as independent risk factors for renal cyst formation. Notably, higher baseline serum potassium was inversely associated with cyst development (OR: 0.37 per 1 mEq/L increase, p = 0.013). Advanced age, male sex, hypertension, and nephrolithiasis were independent predictors of CKD. Cross-sectional GH and absolute IGF-1 levels were not directly associated with CKD or cyst prevalence. Urinary system cancers were among the most frequent malignancies after thyroid cancer, with a greater than seven-fold excess compared to the general population (SIR: 7.38, 95% CI: 2.97–15.21; p < 0.001). Conclusions Renal cysts, CKD, and urinary system malignancies are prevalent in acromegaly. Structural and functional renal alterations may be related to cumulative hormonal exposure and metabolic comorbidities rather than cross-sectional GH/IGF-1 measurements alone, though the absence of matched controls limits causal inference. The inverse association between baseline potassium and cyst risk, and the excess of urinary system cancers, support the need for dedicated renal surveillance in long-term acromegaly management.