📃 Paper Title: Active surveillance of small renal masses: progression patterns of early stage kidney cancer
🧍 Author: Jewett
🕒 Year: 2011
📚 Journal: European Urology
🌎 Country: Canada
ㅤContext to the study:
What do you know about the evidence for surveillance of the small renal mass?
ㅤ✅ Take-home message of study:
• Jewett et al. studied the outcomes of surveillance* of 209 small renal masses (SRMs) in 178 patients deemed to be poor candidates for surgical intervention due to advanced age, comorbidity or patient preference, for mean 28 months
• Percutaneous biopsy was performed in 101 lesions
• The majority of lesions did not grow, or grew slowly (mean 0.13cm/year), even if biopsied as RCC (NB majority Fuhrman 1 or 2)
• Local progression occurred in 12% (25 patients)
• Metastases arose in 1.1% (2 patients)
• Findings confirm that many SRMs can be managed conservatively in the first instance. Delayed intervention if progression occurs is unlikely to detrimentally affect outcomes for the majority of patients (bearing in mind 'unfit' cohort and risk of metastases not zero)
*Surveillance protocol for malignant/unknown histology was US, CT or MRI at 3 months and 6 months, then 6 monthly for 3 years, then annually. Surveillance for biopsy-proven benign was annual imaging. Baseline CXR required.
ㅤ Multicentre prospective cohort study (phase 2 clinical trial)
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Study participants:
• 178 patients from 8 Canadian centres
• Mean age 73 (41-96) years
• Mean SRM dimension 2.1cm (0.4-4cm)
• Inclusion (Disease): Localised (T1aN0M0) SRM (i.e. 4cm or smaller) diagnosed within past 12 months. Biopsied/not biopsied and any histology eligible
• Inclusion (Patient): Determined to be relatively unfit for surgical intervention but with life expectancy of 2 years or more. No dx of hereditary cancer syndrome. Not receiving systemic tx for another malignancy
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Key study outcomes:
• Mean follow up 28 months
• 101 lesions (99 patients) biopsied at entry. 55% malignant, 12% benign, 33% inconclusive. Most malignant biopsies with grade reported were Fuhrman 1 or 2 (41 of 48)
• Growth rate in 151 SRMs followed for >12 months (mean 28 months), mean increase of 0.13cm/year. Further analysis at last f/u: 63% increase with a mean growth rate of 0.26cm/year, 26% size decrease and 10% stable
• Biopsy proven RCC versus benign did not show difference in growth rates
• Local progression occurred in 12% (25 patients) (growth to 4cm or above, or doubling in volume within 12 months)
• Metastases arose in 2 patients (1.1%). These patients had a 2.4cm and 2.7cm SRM at presentation, and were diagnosed with metastases at 5 months and 12 months respectively
• Of the 25 with local progression, 9 had treatment (nephrectomy or probe ablation), remainder did not due comorbidity etc.
• In addition, 46 patients were taken off the study in first 48 months for variety of reasons; 16 of these had treatment
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Study Limitations:
• Specific to select cohort of patients - can't recommend for young/fit
• Short follow-up
• CXR added as entry criterion halfway through
• Ideally would have had centralised pathology/radiology review for standardisation
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