Predictive Factors for Multiple Metastases of Clear-cell Renal Cell Carcinoma

Background/Aim: Multiple metastases of clear-cell renal cell carcinoma (cc-RCC) worsen therapeutic response and survival. There are few predictive markers for assessment of metastases upon diagnosis, most of which relate to therapeutic response, recurrences, and survival. Our goal was to determine if there is a relationship of leucocyte and platelet counts with the number and location of metastases at initial diagnosis. Stratifying patients by age, we aimed to correlate leucocyte and platelet counts with the number of metastases and their location at first diagnosis.

Materials and Methods: After accurate inclusion and exclusion criteria, three age groups of patients with cc-RCC were defined: 35-50, 51-65 and 66-85 years old. Metastases mapping was applied for each patient by recording their location and number (unique versus multiple sites) and this was correlated to the clinicopathologic factors age, sex, white blood cells and platelets count.

Results: For the group aged 35-50 years, preferred sites of metastasis of cc-RCC were the brain, bone, and liver. Neutrophil count was significantly correlated to brain (p=0.003) and bone (p=0.039) metastases. A predominance of liver metastases in women was observed. Skin metastases were significantly correlated with lymph node metastases (p=0.02). The lowest metastatic rate was found in patients aged 51-65 years. Lung and pleural metastases were predominantly reported in men for this subgroup (p=0.017) and weak positive correlation of these with the neutrophil count was found (p=0.026 and p=0.037, respectively). Negative correlation was identified for brain metastases with leucocyte count (p=0.049) and neutrophil count (p=0.044). Elderly patients (66-85 years old) had the highest metastasis rates, and neutrophil counts were significantly positively correlated with platelet counts (p=0.035).

Conclusion: The metastatic potential of cc-RCC is highly heterogeneous amongst different age subgroups, with a potential for strong clinical impact related to therapy response and development of therapy resistance.