Preoperative risk stratification for recurrence after gross total resection of non-functioning pituitary macroadenomas: The role of tumor volume and 3D anatomical complexity — A retrospective single-center cohort study
Introduction Recurrence after radiologically confirmed gross total resection (GTR) of non-functioning pituitary macroadenomas (NFPMAs) remains a relevant clinical challenge. Research question Which preoperative and perioperative factors are associated with recurrence after radiological GTR of NFPMAs? Material and methods We retrospectively analyzed 212 patients who underwent MRI-guided transnasal transsphenoidal surgery for histologically confirmed NFPMAs between 2007 and 2023 at a single tertiary neurosurgical center. Among these, 94 patients were classified as having radiological GTR based on postoperative MRI and longitudinal interdisciplinary review; 62 showed no recurrence and 32 developed recurrence during follow-up. Demographic variables, tumor configuration, suprasellar and cavernous sinus extension, surgical characteristics, histopathology, volumetric measurements, and pre-/postoperative cortisol levels were evaluated. Tumor volumes were manually segmented. Statistical comparisons included Mann–Whitney U tests, chi-squared tests, and ROC analysis. Results Patients in the recurrence subgroup were significantly younger (mean age, 51.2 vs. 57.1 years; p = 0.008) and had significantly larger preoperative tumor volumes (10.45 cm3 vs. 5.54 cm3; p = 0.022), higher Hardy grades (p < 0.001), higher Knosp grades (p = 0.009), and more frequent suprasellar extension (90.6% vs. 64.5%; p = 0.014). ROC analysis identified a preoperative volume cutoff of 9.22 cm3 (AUC 0.667). Surgical approach, histological subtype, and preoperative visual field deficits were not significantly associated with recurrence. Postoperative cortisol changes differed between groups (p = 0.035). Discussion and conclusion Larger tumor volume and more invasive radiological configuration were associated with recurrence despite radiological GTR. These parameters may help refine postoperative surveillance strategies. Prospective validation is warranted.