Degenerative Changes in Aging Human Pelvic Lymph Nodes—A Reason to Rethink Staging and Therapy of Regional Malignancies?

SIMPLE SUMMARY: Therapy and outcome of urological tumors of the small pelvis depend on preoperative staging and surgical results. In this context, the lymph node status plays a significant role. Lymphogenic metastasis of urological tumors is not fully understood to date. Age-dependent changes in lymph node architecture have not been fully explored, even though they have an impact on lymph node function and therefore on tumor metastatic behavior. In this study, it was shown that the pelvic lymph nodes show more degenerative changes with age, such as increased lipomatous atrophy, calcifications, framework and capsular fibrosis. In addition, a smaller lymph node diameter was observed more frequently with increasing age. The authors believe that a better understanding of age-related lymph node changes can contribute to increasing the quality of staging and therapy. ABSTRACT: Lymph node metastases are common in pelvic urological tumors, and the age-related remodeling process of the pelvic lymph nodes influences metastatic behavior. The aim of this work is to characterize age-related degenerative changes in the pelvic lymph nodes with respect to their occurrence and extent. A total of 5173 pelvic lymph nodes of 390 patients aged 44 to 79 years (median 68 years, IQR 62–71 years) were histologically examined for degenerative structural changes. Lymph node size, lipomatous atrophy, capsular fibrosis, framework fibrosis, and calcifications were recorded semi-quantitatively and evaluated by age group. Significantly more lymph nodes <10 mm were found in older patients (p = 0.001). The incidence of framework fibrosis, capsular fibrosis, and calcifications increased significantly with increasing patient age (p < 0.001). In lipomatous atrophy, an increase in mild to moderate lipomatous atrophy was observed with increasing age (p < 0.001). In this, the largest study to date on this topic, age-related degenerative changes in pelvic lymph nodes were proven. Due to the consecutive decrease in hte filtration function of pelvic lymph nodes with increasing age, staging and therapy of metastatic pelvic urologic carcinomas should be reconsidered.