Quality of bladder cancer surgery – improving outcomes
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Date
30/06/2018Item status
Restricted AccessEmbargo end date
31/12/2100Author
Mariappan, Paramananthan
Metadata
Abstract
Background: At the time of diagnosis, approximately 75% of all bladder cancers are
Non-Muscle Invasive Bladder Cancers (NMIBC) - the standard treatment for these
cancers is a Transurethral Resection of the Bladder Tumour (TURBT). Although, the
vast majority of these cancers are not life-threatening, they have a high risk of
recurrence (and progression, particularly in higher risk NMIBC), despite the use of
adjuvant intravesical chemotherapy. Consequently, patients are kept on long term
cystoscopic surveillance with endoscopic removal if recurrences are detected – this
impacts on patients’ quality of life and contributes to the high cost for the healthcare
provider.
Aims: The fundamental aim of this series of clinical studies, spanning 12 years, was
to identify and implement, means of improving the efficiency in both processing and
operating on patients with NMIBC to not only reduce recurrence, but also to reduce
the duration of follow up and repeat operations. It was an evolutionary process where
the findings in the preceding studies formed the basis of the subsequent one - while
the aim of the individual studies were different, there was a clear link to the essential
principles, thus forming a coherent collection of studies.
Methods and results: The project was carried out in 3 phases (with 2 or 3 main studies
in each phase, augmented by 1 to 2 linked studies – making the entire submission for
PhD by publications a series of 12 studies, to date):
Phase 1 (5 studies in this phase): The aim was to demonstrate the natural history of
non-invasive bladder cancer and identify sub-categories of patients who could be
discharged from surveillance at 5 years. This was initially achieved by evaluating a
prospectively maintained cohort of non-invasive bladder cancer patients diagnosed
between 1978 and 1984 at the Western General Hospital, Edinburgh. This study
identified the importance of the recurrence rate at the first follow up cystoscopy
(RRFFC) as an essential prognostic marker. This finding was further validated using
2 separate cohorts from a different Centre (the Royal Infirmary, Edinburgh) managed
in the 80s and the 90’s, respectively. The data confirmed that over the decades,
recurrence patterns do change, possibly as a result of differing techniques and
improvements in optics and instruments; however, what remained the same was the
prognostic value of the RRFFC.
Phase 2 (3 studies in this phase): The early recurrence was deemed to be the result of
missed and tumours left behind at the initial TURBT, i.e. a marker of quality.
However, RRFFC was only known 3 months after the initial surgery. Since the RRFFC
was such an important prognostic factor, the aim of this phase was to determine the
surgical factors contributing to the quality of TURBT and subsequently implement
changes to the principles in carrying out the surgery to improve this quality. This was
achieved by prospective collection of information regarding all patients undergoing
TURBT for new bladder cancers, recording the tumour features, surgeon experience,
if the resection was deemed to have been complete or not, and the pathological results.
We identified that the detrusor muscle in the resected specimen and the experience of
the surgeon were independent determinants of TURBT quality. This finding was
validated in a further study using cohorts from another time period and another Centre
– this allowed me to develop the concept of Good Quality White Light TURBT
(GQWLTURBT) as the benchmark for the white light TURBT. Phase 3 (4 studies in this phase): Photodynamic Diagnosis assisted TURBT (PDDTURBT)
was demonstrated in randomised controlled trials as a technique that reduces
the recurrences in NMIBC. In the absence of evidence with this technique in the ‘real
life’ setting nor comparisons with standardised, benchmarked white light TURBT
technique, we performed a prospective controlled study comparing PDD-TURBT and
GQ-WLTURBT, evaluating early and delayed recurrence rates in 2 separate studies. I
also performed a multicentre UK study on the outcomes with PDD-TURBT and
collaborated with other experts in Europe in producing a review article around
Photodynamic Diagnosis and the cost effectiveness of this technique.
Summary: This coherent series of studies has contributed to knowledge in bladder
cancer surgery by, among others: (a) mapping the individual patient natural history of
non-invasive bladder cancer; (b) confirming the importance of early recurrence as a
strong prognostic indicator; (c) identifying predictors of this early recurrence and the
quality of TURBT; (d) introducing the concept of the benchmark Good Quality White
Light TURBT and (e) demonstrating the benefits of photodynamic diagnosis within a
‘real life’ setting.