Morphological Characterization of Papillary Renal Cell Carcinoma Type 1, the Efficiency of Its Surgical Treatment

Abstract

Aim: Papillary renal cell carcinoma type 1 (pRCC1) represents the second most common type of malignant renal epithelial tumour. The origin of its characteristic appearance, its growth mechanism, and the long-term efficiency of its surgical treatment remain uncertain. Our aim was to determine typical characteristics of surgically treated pRCC1. Methods: pRCC1 was verified in 83 of 1,629 (5.1%) kidney tumours surgically treated in the period of January 2007-January 2016. The clinical and radiological characteristics, type of surgery, histopathology results and follow up data were recorded. Spearman correlation, Kruskal-Wallis analysis of variance, Fisher's exact, and chi-square test were used to analyse appropriate variables. The overall survival rate was evaluated using the Gehan-Wilcoxon test and the Cox proportional hazards model. Results: The mean tumour size was 52.0 mm (15-180); 98.8% of the tumours showed a spherical shape and in 82.1%, exophytic growth was observed. Partial nephrectomy was performed in 80.7%. A majority (81.9%) were classified as pT1. Tumours, 89.2% of them, belonged to Fuhrman grade 1 or 2. The mean follow-up was 46.8 months. The overall survival was associated with pT category (p ≤ 0.0001). Conclusions: Typical signs of pRCC1 are a spherical shape, exophytic growth and low Fuhrman's grade. More than three-fourths of pRCC1 could be treated by the nephron-sparing surgery.

Cystic Appearance on Imaging Methods (Bosniak III-IV) in Histologically Confirmed Papillary Renal Cell Carcinoma is Mainly Characteristic of Papillary Renal Cell Carcinoma Type 1 and Might Predict a Relatively Indolent Behavior of Papillary Renal Cell Carcinoma

“…Its neoplastic tissue is more likely to undergo necrosis [4,9,12]. This necrosis can imitate a cyst on radiological examination, especially on CT.…”