Minimally Invasive Partial Versus Total Adrenalectomy for the Treatment of Primary Aldosteronism: Results of a Multicenter Series According to the PASO Criteria

Background: Determination of success after adrenal-sparing surgery for primary aldosteronism (PA) is limited by the lack of standardized definitions of outcomes.

Objective: To evaluate the safety and effectiveness of minimally invasive partial adrenalectomy (MIPA) for PA by comparing perioperative and functional outcomes with minimally invasive total adrenalectomy (MITA) according to the Primary Aldosteronism Surgical Outcome (PASO) criteria.

Design, setting, and participants: Between March 2011 and April 2020, a multicenter adrenalectomy dataset was queried for "unilateral adrenal mass, PA, MIPA (n = 29), or MITA (n = 61)"at four participating Institutions.

Intervention: MITA and MIPA for PA.

Outcome measurements and statistical analysis: Differences between continuous variables were assessed with the Wilcoxon rank sum test, while Pearson's χ² test was used for categorical data. Complete, partial, and absent clinical success rates were assessed for the overall cohort and compared between groups.

Results and limitations: The median tumor size was significantly higher in the MITA group (4.2 vs 2.7 cm; p = 0.001), while preoperative hypertension rate was significantly higher in the MIPA series (82.8% vs 57.4%, p = 0.01). The median length of hospital stay was increased in the MITA cohort (4 vs 3 d; p = 0.038). Overall, at a median follow-up of 42 mo (interquartile range 27-54 mo), complete, partial, and absent clinical success was observed in 60%, 17.7%, and 22.3% of cases, respectively. The complete clinical success rate was higher in the MIPA group (72.4% vs 54.1%), while a partial clinical success was higher in the MITA series (23% vs 6.8%). The absence of clinical success was comparable between groups (MITA 23% vs MIPA 20.7%).

Conclusions: MIPA showed excellent perioperative results with a complete clinical success rate of 72.4%. Owing to the heterogeneity of the PASO criteria in the assessment of partial or absent success, the quest for a univocal definition of satisfactory clinical outcomes in the treatment of PA remains open.

Patient summary: We compared minimally invasive partial adrenalectomy (MIPA) and minimally invasive total adrenalectomy for the treatment of unilateral primary aldosteronism, assessing the outcomes with the Primary Aldosteronism Surgical Outcome (PASO) criteria. MIPA seems to provide comparable perioperative outcomes and midterm clinical success rates.