Presentation Authors: Stefania Zamboni*, Lucerne, Switzerland, Beat Foerster, Mohammad Abufaraj, Vienna, Austria, Morgan Rouprêt, Thomas Seisen, Paris, France, Pierre Colin, Lille, France, De la Taille Alexandre, Paris, France, Benoit Peyronnet, Karim Bensalah, Rennes, France, Roman Herout, Manfred Peter Wirth, Vladimir Novotny, Dresden, Germany, Francesco Soria, Vienna, Austria, Piot Chlosta, Krakow, Poland, Agostino Mattei, Philipp Baumeister, Lucerne, Switzerland, Alessandro Antonelli, Claudio Simeone, Brescia, Italy, Francesco Montorsi, Milan, Italy, Giuseppe Simone, Michele Gallucci, Giuseppe Romeo, Rome, Italy, Kazumasa Matsumoto, Kanagawa, Japan, Pierre I Karakiewicz, Montreal, Canada, Alberto Briganti, Milan, Italy, Evanguelos Xylinas, Paris, France, Shahrokh F. Shariat, Marco Moschini, Vienna, Austria
Introduction: upper tract urothelial carcinoma (UTUC) is an aggressive tumor, associated with poor oncological outcomes. The presence of variant histology is associated with poor survival outcomes in bladder cancer patients, but sparse data exists regarding its role in UTUC. Aim of our study is to evaluate survival outcomes of histologic variants in UTUC patients treated with radical nephroureterectomy (RNU).
Methods: we retrospectively analyzed data of 1,610 patients treated with RNU for clinical non-metastatic UTUC between 1990 and 2016 in several center participating of the UTUC Collaboration. Performance and extend of lymph node dissection was chosen according to surgeon preference and was not standardized. Histologic variants were classified in micropapillary, squamous, sarcomatoid. Other histologic variants were included in &[Prime]others&[Prime] group as consequence of their rarity. Multivariable competing risk analyses was built to predict effect of different types of variant on overall recurrence (RFS) and cancer specific mortality (CSM).
Results: Overall, 1,460 (91%) had pure urothelial carcinoma whereas 150 (9%) were diagnosed with a variant histology. Of them 89 (5.0%) had micropapillary variant, 41 (2.0%) had squamous, 10 (1.0%) had sarcomatoid and 10 (1.0%) had &[Prime]others&[Prime]. At competing risk analyses, micropapillary variant was the only significant variant associated with worse RFS (Hazard ratio [HR]: 2.49, 95% Confidence Interval [CI], 1.29-4.82, p=0.006) whereas sarcomatoid variant was associated with CSM (HR: 20.63, CI: 9.39-45.31, p < 0.001) (Figure 1).
Conclusions: we found that about one-tenth of patients with UTUC have histologic variants but only micropapillary and sarcomatoid variants were associated with poorer oncological outcomes at multivariable analyses.