To assess if 'tumour budding' (TB) behaves as a poor prognostic factor in muscle-invasive bladder carcinoma (MIBC). TB is the presence of tumour cells isolated or in small groups of fewer than five cells located at the tumour invasion front.
Retrospective study of 106 patients with MIBC who underwent radical cystectomy. A cytokeratin AE1/AE3 immunostaining was applied to identify and quantify TB by the 'hot-spot' method. The variables evaluated were: age, gender, TNM stage, associated CIS, differentiation degree, tumour size, tumour location, lymphatic, venous or perineural invasion, p53, Ki67, molecular subtype (basal/luminal) and chemotherapy. Main variables were overall and cancer-specific survival.
The mean follow-up time was 47 ± 46.45 months. The mean TB count was 32.3 ± 25.9 'buds'. The ROC curve established 14 'buds' as the cut-off point: the median survival rate for the 'low-grade TB' group (≤14 'buds') was 69.5 months, and for the 'high-grade TB' group (>14 'buds') was 18.5 months (p = 0.003). In the multivariate analysis, independent predictive variables regarding mortality were: age, TB and TNM stage. Patients with more than 14 'buds' had 2.27 times more risk of mortality, CI95%:1.19-4.34, p = 0.013. In addition, the risk of mortality rises progressively as the number of 'buds' increases, at a rate of 2% per 'bud'.
According to our results, TB becomes an independent predictor factor for cancer-specific mortality in MIBC, with a cut-off point of 14 'buds'.
Urology. 2019 Apr 12 [Epub ahead of print]
Laura Lorenzo Soriano, Guzmán Ordaz Jurado, José Luis Pontones Moreno, Sara Villarroya Castillo, Soraya Hernández Girón, Iván Sáez Moreno, David Ramos Soler
Department of Urology, Hospital University La Fe, Valencia, Spain. Electronic address: ., Department of Urology, Hospital University La Fe, Valencia, Spain. Electronic address: ., Department of Urology, Hospital University La Fe, Valencia, Spain. Electronic address: ., Department of Urology, Hospital University La Fe, Valencia, Spain. Electronic address: ., Department of Pathology, Hospital University La Fe, Valencia, Spain. Electronic address: ., Department of Urology, Hospital University La Fe, Valencia, Spain. Electronic address: ., Department of Pathology, Hospital University La Fe, Valencia, Spain. Electronic address: .