Value of Tumor's Depth and Width in Predicting Survival Rate in Non-Muscle-Invasive (pT1) Bladder Cancer

Albert , Kevin Anthony Glorius Tampubolon , Sawkar Vijay Pramod , Ferry Safriadi  

Department of Urology, Universitas Padjadjaran, Indonesia

 

Correspondences to: Sawkar Vijay Pramod; email: doktervj@yahoo.co.id

Received: 23 Feb 2022; Revised: 31 May 2022; Accepted: 15 Jun 2022; Available online: 19 Sep 2022

Abstract

Background

Bladder cancer is classified according to traditional American Joint Committee on Cancer TNM staging. In the absence of nodal (N stage) or distant metastases (M stage), the depth of tumor invasion (T stage) is the most important determination to be made: whether the tumor is invading into or beyond the lamina propria (muscle-invasive bladder cancer) or not (non-muscle-invasive bladder cancer). This study investigated the association between the cutoff value of tumor depth and width and survival rate in non-muscle-invasive (pT1) bladder cancer. 

Materials and methods

This was a retrospective cohort design of randomly selected, single-centered study. The subjects were patients with pT1 urothelial carcinoma who were diagnosed on transurethral resection of bladder specimens at a tertiary hospital in West Java, Indonesia. The research sample was taken by consecutive sampling from 2015 to 2019.  

Results

Sixty-four patients from were included in this study. A tumor depth >2 mm resulted in a hazard ratio (HR) of 1.41 (95% confidence interval [CI], 1.27–3.94; p<0.007), with significant difference. A tumor width >2.4 mm also increased HR significantly (3.27; 95% CI, 1.69–5.87; p<0.006). The presence of lymphovascular invasion (LVI) in patients with bladder cancer resulted in an HR of 3.66 (95% CI, 1.5–4.77; p<0.001), with statistically significant difference in overall survival (OS). 

Conclusion  

Tumor invasion depth, tumor width, and LVI appear to be predictive of poor prognosis in terms of OS in patients with pT1 bladder cancer.

Key words: Non-muscle-invasive, Bladder cancer, Survival rate

Ann Afr Surg. 2022; 19(4): 180-185

DOIhttp://dx.doi.org/10.4314/aas.v19i4.4

Conflicts of Interest: None

Funding: None

© 2022 Author. This work is licensed under the Creative Commons Attribution 4.0 International License.Albert , Kevin Anthony Glorius Tampubolon , Sawkar Vijay Pramod , Ferry Safriadi

 

Introduction

Bladder carcinoma, which has an annual incidence rate of 430,000 cases, is the eleventh most diagnosed cancer worldwide, but it ranks eighth among male populations. In Indonesia, the overall incidence of bladder cancer is estimated to be 7 in 100,000. According to the 2020 GLOBOCAN data, the incidence of bladder cancer in Indonesia ranks 14th worldwide, with 6716 new cases (1.9%), but the precise incidence rate is hard to determine, especially the non-muscle-invasive bladder cancer (NMIBC) type (1). In a previous study from a tertiary hospital, of 464 patients diagnosed with bladder cancer, 36 (7.76%) had NMIBC. The incidence and mortality rates of bladder cancer vary greatly across different countries because of differences in risk factors, early detection and diagnostic applications, and availability of treatments (2).
At presentation, 90% of bladder cancers are confined to the bladder wall layers, and of all localized bladder cancers (≤T2), 75% are non-muscle-invasive (Tis, Ta, T1) (3, 4). A long-term study of high-risk NMIBC, including T1 tumors, showed progression and cancer death rates as high as 53% and 34%, respectively (5). This pT1 group has high prognosis variability, and thus, involves the most difficult clinical decisions. Some patients experience no recurrence after initial transurethral resection of the bladder (TURB); meanwhile, some patients show recurrence and stage progression after initial therapy (4). Therefore, prognostication in pT1 group is urgently needed.
T1 tumors represent approximately 25% of NMIBCs. Recognition of early invasion (stage pT1) in urothelial neoplasia is one of the most challenging areas in bladder pathology. Many studies have attempted to stratify T1 tumors by depth of invasion into the lamina propria, but they have had variable success. Invasion of the lamina propria, tumor grade, and carcinoma in situ (CIS) represent significant risk factors for the progression of NMIBC. Owing to its heterogeneity, numerous efforts have been made to identify the subset of T1 carcinomas that carries a high risk of disease recurrence and progression (6). 
In a previous study, human papillomavirus status in patients with pT1 bladder cancer had no significant effect on in disease progression (7). However, tumor invasion beyond the lamina propria has shown higher recurrence and progression rates than more superficial invasions. In addition, some investigators have shown that the millimetric depth of invasion measured by a micrometer can be an accurate predictive factor with a significant cutoff invasion depth of 1.5 mm. Lymphovascular invasion (LVI) is also a determining factor in the progression and mortality of bladder cancer (8). The parameters used to predict the prognosis of pT1 patients, i.e., early stages, tumor grade, quantity of tumors, and presence of carcinoma in situ (CIS), cannot accurately predict the patients’ prognosis, especially in patients with pT1 tumors (9).
In the present study, we aimed to evaluate the pathologic parameters of tumor correlated with overall survival (OS) rate in pT1 bladder cancer.