Consolidative Renal Cell Carcinoma Metastatectomy for Partial Response After Multitargeted Tyrosine Kinase Inhibitor Therapy

Tumour response in metastatic renal cell carcinoma treated with tyrosine kinase inhibitors - assessment of intra-tumour heterogeneity

Intra-tumour heterogeneity is a common molecular phenomenon in metastatic clear cell renal carcinoma (mRCC), representing the genetic complexity of a tumour with multiple metastatic sites. The present commentary discusses the observed phenomena of phenotypic intra-tumour heterogeneity in mRCC patients treated with the tyrosine kinase inhibitors sunitinib or pazopanib. Here, drug response can be different on the level of each evaluated metastasis in the individual patient. This questions the currently used radiologic staging systems of RECIST criteria and demands for a modification of radiologic response assessment with the consequence of a patient-tailored therapy in the clinical setting.Please see related article: http://bmcmedicine.biomedcentral.com/articles/10.1186/s12916-016-0729-9 .

Surgical outcomes and complications associated with presurgical tyrosine kinase inhibition for advanced renal cell carcinoma (RCC)

BACKGROUND

Tyrosine kinase inhibitors (TKI) have dramatically changed the management paradigm of advanced renal cell carcinoma (RCC) and are increasingly being used preoperatively to achieve cytoreduction.

OBJECTIVE

To review our case series of post-TKI surgical procedures to add to the current perioperative efficacy and complication profile.

MATERIALS AND METHODS

Between October 2006 and February 2010, 14 cytoreductive nephrectomies, radical nephrectomies, and metastectomies were performed after neoadjuvant sunitinib or sorafenib for advanced RCC. During the same time frame, a control group of 73 consecutive patients underwent radical nephrectomy, cytoreductive nephrectomy, or metastectomy in the absence of prior systemic therapy. We compared the incidence of perioperative complications and outcomes after surgical procedures between the two cohorts.

RESULTS

Median preoperative renal mass size was 11 cm (6.7-24.2 cm). Primary tumor shrinkage was seen in 57%; median shrinkage was 18% (8%-25%). The median treatment period was 17 weeks, and the median time from TKI discontinuation was 2 weeks. Compared with a control group and after adjusting for confounding covariates, presurgical TKI use was not associated with a significant increase in perioperative complications (50% vs. 40%, P = 0.25) or perioperative bleeding (36% vs. 34%, P = 0.97) but was associated with increased incidence and grade of intraoperative adhesions (86% vs. 58%, P = 0.001; grade 3 vs. 1, P = 0.002).

CONCLUSIONS

Compared with the published reports, we observed less hemorrhagic and wound healing issues but a significant increase in incidence and severity of intraoperative adhesions, which can present a formidable technical challenge. Potential reasons for our lower complication rate could be increased time from TKI discontinuation to surgery, longer time to postoperative TKI re-initiation, increased use of preoperative angioembolization, and the lack of preoperative bevacizumab administration. Presurgical TKI therapy can permit effective surgical cytoreduction with a safety and complication profile equivalent to that of non-TKI-nephrectomy; however safety data continue to evolve, and preoperative TKI use requires further prospective investigation.

Outcome of treatment discontinuation in patients with metastatic renal cell carcinoma and no evidence of disease following targeted therapy with or without metastasectomy

BACKGROUND

It is unknown if discontinuation of targeted therapy (TT) and readministration in case of recurrence is feasible in patients with metastatic renal cell carcinoma (mRCC) in which complete response (CR) is achieved by TT alone or no evidence of disease (NED) with additional resection of residual metastases.

PATIENTS AND METHODS

Patients in whom TT was discontinued after CR to TT alone or NED after additional metastasectomy were included in this retrospective analysis. Outcome criteria evaluated were time off TT, recurrence of metastases and response to re-exposure to TT. Univariate and multivariate analyses were carried out to identify variables potentially predictive of outcome.

RESULTS

In 36 patients with CR or NED under TT with sunitinib (22), sorafenib (11), bevacizumab/interferon (2) and temsirolimus (1), TT was discontinued. Recurrence was observed in 24 patients (66.7%). Re-exposure to TT was effective in 86.9% of these cases. Twelve patients (33.3%) remained recurrence free at a median follow-up of 12 months (range 3-31). Median time off TT was 7 months (range 1-31). Factors that correlate with outcome could not be identified.

CONCLUSIONS

In the majority of patients with mRCC and CR or NED, discontinuation of TT was followed by recurrence, but re-exposure to TT was effective.

Can tyrosine kinase inhibitors be discontinued in patients with metastatic renal cell carcinoma and a complete response to treatment? A multicentre, retrospective analysis

BACKGROUND

Discontinuation of treatment with tyrosine kinase inhibitors (TKIs) and readministration in case of recurrence could improve quality of life (QoL) and reduce treatment costs for patients with metastatic renal cell carcinoma (mRCC) in which a complete remission (CR) is achieved by medical treatment alone or with additional resection of residual metastases.

OBJECTIVE

To evaluate whether TKIs can be discontinued in these selected patients with mRCC.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective analysis of medical records and imaging studies was performed on all patients with mRCC treated with TKIs (n=266) in five institutions. Patients with a CR under TKI treatment alone or with additional metastasectomy of residual disease following a partial response (PR), in which TKIs were discontinued, were included in the analysis. Outcome criteria analysed were time to recurrence of previous metastases, occurrence of new metastases, symptomatic progression, improvement of adverse events, and response to reexposure to TKIs.

INTERVENTIONS

Sunitinib 50mg/day for 4 wk on and 2 wk off, sorafenib 800mg/day.

MEASUREMENTS

Response according to Response Evaluation Criteria in Solid Tumours (RECIST).

RESULTS AND LIMITATIONS

We identified 12 cases: 5 CRs with sunitinib, 1 CR with sorafenib, and 6 surgical CRs with sunitinib followed by residual metastasectomy. Side-effects subsided in all patients off treatment. At a median follow-up of 8.5 mo (range: 4-25) from TKI discontinuation, 7 of 12 patients remained without recurrence and 5 had recurrent disease, with new metastases in 3 cases. Median time to progression was 6 mo (range: 3-8). Readministration of TKI was effective in all cases. The study is limited by small numbers and retrospective design.

CONCLUSIONS

Discontinuation of TKI in patients with mRCC and CR carries the risk of progression with new metastases and potential complications. Further investigation in a larger cohort of patients is warranted before such an approach can be regarded as safe.