Can contemporary targeted therapies provide clinically meaningful changes in renal cell carcinoma venous tumor thrombi?

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Background: Renal cell carcinoma (RCC) tumor thrombus regression has been reported after treatment with contemporary targeted therapies. We sought to identify clinically meaningful changes in tumor thrombi in a series of patients treated with targeted therapies.

Methods: A University of Texas M. D. Anderson institutional database was queried for patients treated with targeted therapy while the primary RCC remained in situ. The subset of patients with a vascular tumor thrombus was assessed for radiographic responses of tumor thrombi. Pathology was obtained from a percutaneous biopsy or the surgical specimen. The modified Clavien system was used to grade complications within 12 months of surgery. Clinically meaningful changes were defined as changes in the anatomic thrombus level or changes altering surgical approach.

Results: A total of 178 patients were treated with targeted therapy with the primary tumor in situ. Venous tumor thrombus was present in 27% (n=48) and comprised our study cohort. The primary histology was clear cell in 75% of cases and 47/48 patients presented with metastatic disease. Prior to treatment, the tumor thrombus was within the renal vein (RV) in 60% (29/48-Level 0), the first 2 cm of the inferior vena cava in 10% (5/48-Level 1), > 2 cm above the RV in 21% (10/48-Level 2), at the level of the hepatics but below the diaphragm in 6% (3/48-Level 3), and above the diaphragm in 2% (1/48-Level 4). After a median duration of therapy of 2.75 months, clinically meaningful changes occurred in 25% of patients (12/48). Of these, progression occurred in 58% (7/12) while 42% (5/12) had regression of tumor thrombus. Fourteen patients (30%) received surgery after targeted therapy. Clavien categorized complications ≥ grade 3 occurred in 50% of surgical cases. No patient experienced a pulmonary embolism with treatment or during follow up.

Conclusions: To our knowledge,this is the largest reported series of RCC patients with an in-situ venous tumor thrombus treated with targeted therapy. Although no patient experienced a pulmonary embolism, the use of targeted therapy with the primary goal of obtaining clinically meaningful reductions in tumor thrombi does not appear to be a promising therapeutic option.

No significant financial relationships to disclose.

Use of early primary tumor response to predict overall survival in patients with metastatic RCC undergoing treatment with sunitinib

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Background: In metastatic renal cell carcinoma (mRCC) patients treated with sunitinib and the primary tumor in situ, there is minimal predictive data available to help guide clinicians during treatment with targeted therapy. In prior studies, early primary tumor response (PTR) was associated with improved overall PTR, but the effect on overall survival (OS) is unknown. The purpose of our study was to evaluate whether early PTR was associated with improved OS in mRCC patients undergoing treatment with sunitinib.

Methods: We reviewed our institutional database to identify patients with mRCC treated with sunitinib with primary tumor in situ. Clinical and pathological data were collected for each patient. Sequential abdominal CT or MRI scans were reviewed to evaluate PTR. Early PTR was defined as ≥ 10% decrease in tumor diameter within the first 90 days of treatment. Univariable and multivariable stepwise Cox proportional hazards regression analysis were performed to identify predictors of OS in these patients.

Results: 75 consecutive patients were identified between 2005 and 2009 with a median follow-up of 15 months. 24 patients exhibited an early PTR; median maximum response 23.1% (range: −53.4, −10.2) and decrease in primary tumor diameter at a median of 90.5 days. Early PTR was associated with a decreased risk of death on multivariate analysis (HR: 0.18; 95% CI 0.05, 0.62, p<0.01). In addition, median OS was improved in patients with an early PTR (30.2 vs. 12.7 months). Independent predictors of decreased survival on multivariate analysis included local symptoms, multiple bone metastases, clinical evidence of venous thrombus, LDH > upper limit of normal, and >2 visceral metastatic sites.

Conclusions: Early PTR ≥ 10% is associated with improved survival, better response in metastatic sites, and better overall PTR in patients with mRCC. Future studies should consider this variable when evaluating sunitinib in mRCC treatment.

[Table: see text]

Long-term survival of patients with metastatic renal cell carcinoma (mRCC) treated with targeted therapy (TT) without cytoreductive nephrectomy (CN)

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Background: We recently reported on 188 patients (pts) with mRCC treated with TT without CN [Richey et al, J Clin Oncol 28:15s, 2010 (suppl; abstr 4613); Annals of Oncology- in press]. We report here outcome data on pts who survived > 24 months (mos).

Methods: We retrospectively reviewed records of patients with mRCC who received TT without CN and survived longer than 24 mos from treatment initiation. Pts did not undergo CN due to medical comorbidity, unresectable primary tumor, heavy disease burden, or patient preference. Kaplan-Meier methods were used to estimate median overall survival (OS). Long-term complications related to therapy were evaluated.

Results: 22 pts were identified meeting the inclusion criteria. Median follow-up was 30.4 mos (range, 24.1- 68.7), with median OS time of 34.1 mos (95% CI: 30.2, 37.2). Median time on therapy (TOT) was 25.3 mos (IQR: 13.7, 28.5). Six pts (27.3%) were alive at the time of analysis, with median TOT of 26.9 mos (range: 13.7, 62.5) (IQR: 24.6, 33.4). Eastern Cooperative Oncology Group performance status was 0 or 1 in 86% of pts. Ten (45%) and 12 (55%) pts had intermediate- and poor-risk disease by Heng et al criteria (JCO 2009), respectively. Patients received the following types of TT: sunitinib 14 (63.6%), sorafenib 13 (59.1%), temsirolimus 5 (22.7%), bevacizumab 5 (22.7%), pazopanib 3 (13.6%), everolimus 4 (18.2%), erlotinib 3 (13.6%), investigational targeted agent 1 (4.6%). Four (18.2%), 5 (22.7%), and 13 (59.1%) pts received 1, 2, or ≥ 3 different therapies, respectively. During treatment with TT, 6 pts (27.3%) developed hypertension, 6 pts (27.3%) developed hypothyroidism, 2 pts (9.1%) developed congestive heart failure, 1 pt (4.6%) developed stroke. No pts developed bleeding or myocardial infarction. By radiographic assessment of best primary tumor response, 4 (18.2%) pts had a partial response (≥30% decrease), 10 (45.5%) exhibited a decrease <30%, and 6 (27.3%) had stable or increased size of the primary tumor.

Conclusions: These data highlight the potential for long-term survival of patients with mRCC treated with TT without CN, and underscore the challenges in managing therapy-related long-term adverse events.

No significant financial relationships to disclose.

Postoperative complications from cytoreductive nephrectomy after neoadjuvant targeted therapy for metastatic renal cell carcinoma

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Background: Neoadjuvant treatment of metastatic renal cell carcinoma (RCC) with targeted systemic therapies is under investigation. Postoperative complications that occurred after cytoreductive nephrectomy (CRN) preceded by neoadjuvant systemic therapy were assessed.

Methods: A retrospective review of all patients with clinical evidence of metastasis that underwent CRN was performed. Of 683 surgical patients with metastatic disease, 67 had received preoperative targeted therapy. Preoperative, operative, and postoperative characteristics were evaluated for each patient. Surgical complications were assessed using the modified Clavien system. A multivariate was sued to determine preoperative variables in an attempt to predict surgical complications within 1 year of CRN.

Results: Complications occurred in 64% (43/67) of patients within 365 days of CRN. Clavien grade ≥ 3 complications occurred in 30% (20/67) patients. The most common occurrences were superficial wound dehiscence (25%), and wound infection (15%). On univariate analysis there were no statistically significant differences between groups in regards to age, race, gender, smoking history, follow-up, Charlson comorbidity index, MSKCC risk groups, or time from cessation of targeted therapy to surgery. Significant predictors of complications included BMI ≥ 30 (p=0.007), EBL (p=0.019), matted nodes (p=0.043), and surgical approach (p=0.001). Clinical T-stage and N-stage (p=0.068, p=0.073) approached significance. On multivariate analysis Charlson comorbidity index ≥ 8(OR 5.2, 95% CI 1.23, 21.99) and clinical N-stage (OR 5.11, 95%CI 1.21, 21.66) were significant predictors of postoperative complications.

Conclusions: In this series of patients treated with neoadjuvant targeted therapy, a majority of patients experienced a postoperative complication after CRN. A Charlson comorbidity index ≥ 8 or clinical node positivity predicted for an increased risk of postoperative complications. The use of neoadjuvant systemic targeted therapy prior to CRN is investigational and adequate assessment of operative morbidity is needed prior to wide spread adoption.

No significant financial relationships to disclose.

Outcome of patients with metastatic renal cell carcinoma treated with targeted therapy without cytoreductive nephrectomy

BACKGROUND

Cytoreductive nephrectomy (CN) became a standard procedure in metastatic renal cell carcinoma (mRCC) in the immunotherapy era. Historically, median overall survival (OS) of patients treated with interferon alpha (IFN-α) without CN was 7.8 months. Median OS in patients treated with targeted therapy (TT) without CN is unknown.

PATIENTS AND METHODS

We retrospectively reviewed records of patients with mRCC who received TT without CN. Kaplan-Meier methods and Cox regression analysis were used to estimate median OS and identify poor prognostic factors.

RESULTS

One hundred and eighty-eight patients were identified. Most patients had intermediate-risk (54.8%) or poor-risk (44.1%) disease. Median OS for all patients was 10.4 months [95% confidence interval (CI) 8.1-12.5]. By multivariable analysis, elevated baseline lactate dehydrogenase and corrected calcium, performance status of two or more, retroperitoneal nodal metastasis, thrombocytosis, current smoking, two or more metastatic sites, and lymphopenia were independent risk factors for inferior OS. Patients with four or more factors had increased risk of death (hazard ratio 8.83, 95% CI 5.02-15.5, P < 0.001) and 5.5-month median OS. Nineteen patients (10.0%) survived for 2+ years.

CONCLUSIONS

These data highlight the improved OS of patients with mRCC treated with TT without CN, compared with historical IFN-α treatment, and may guide the design of trials investigating the role of CN in the TT era.

Outcome of patients (pts) with metastatic renal cell carcinoma (mRCC) treated with systemic therapy without cytoreductive nephrectomy (CN)

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Background: Targeted therapies (TT) have replaced cytokines in the management of pts with mRCC. CN has been incorporated in the management of pts with mRCC but many pts are not suitable candidates for CN. The median overall survival (OS) time of pts treated with interferon alfa (IFN-α) without CN was 7.8 months (mos) [Flanigan et al. Journal of Urology 2004]. The median OS time for pts with mRCC treated with TT sequentially without CN is unknown. Methods: We retrospectively reviewed the medical records of pts with mRCC who did not undergo CN and who received one or more TT (bevacizumab, sorafenib, sunitinib, or temsirolimus) sequentially for at least one month with or without chemotherapy (gemcitabine + capecitabine or 5-FU). We calculated OS time from date of diagnosis until date of death or last follow up. We excluded pts who had embolization, radiofrequency ablation or cryotherapy of the primary tumor. Results: We identified 88 pts between Jan 2002 and Dec 2007. Median follow-up time is 9.7 mos (range: 1.2–49.2). Median OS time for all pts is 10.7 mos (95% CI: 7.6–15.4). 55 pts (62.5%) had clear-cell and 33 (37.5%) had non-clear cell histology, with median OS times of 15.1 mos (95% CI: 9.6–17.7) and 7.4 mos (95% CI: 4.4–13.0), respectively. ECOG performance status (PS) at time of diagnosis was correlated with OS (HR 1.54; 95% CI: 1.16–2.05; p<0.01). Pts with PS 0, 1, 2, and 3 had median OS times of 22.8 mos (95% CI: 5.7,*), 16.5 mos (95% CI: 8.1–24.7), 7.6 mos (95% CI: 5.7–11.9), and 7.1 mos (95% CI: 3.3–9.6), respectively. Pts with clinical evidence of lymph node (LN) involvement had worse outcome,with median OS time of 7.6 mos (95% CI: 5.6–9.8) versus 17.2 mos (95% CI: 9.8–35.5) for pts without clinical evidence of LN involvement. Conclusions: In this analysis, median OS time for pts with mRCC treated in the modern era with TT without CN is superior to historical experience with IFN- α.Compromised PS, LN involvement, and non-clear cell histology were associated with worse outcome. This data is useful in the design of randomized trials investigating the role of CN in mRCC.

[Table: see text]

Suppression of tumorigenicity in the human prostate cancer cell line M12 via microcell-mediated restoration of chromosome 19

Previously we immortalized human, nontransformed prostate epithelial cells with SV40 large T-antigen (SV40TAg) and derived increasingly aggressive sublines from the immortalized line. The progression of the tumorigenic sublines to metastatic capacity was accompanied by the formation of an unbalanced translocation between chromosomes 16 and 19, resulting in loss of 19p and proximal 19q. To test whether the tumorigenic and/or metastatic phenotype was causally related to this genetic alteration, we restored a neo-tagged human chromosome 19 to M12 cells by microcell-mediated transfer and assessed their growth. In vitro, the resultant hybrids grew more slowly in monolayer culture and showed a significant reduction in anchorage-independent growth as compared to M12neo controls. In vivo, all mice (13/13) injected subcutaneously (SC) with control M12neo cells developed tumors after 9-15 days. In contrast, 9/15 mice injected SC with microcell-transferred chromosome 19 hybrid cells failed to form tumors, with 6/15 producing very small tumors after 120 days. Analysis of three of these six tumors showed consistent, new chromosomal changes. Furthermore, in one of the tumors, loss of a chromosome 19 was noted in 40% of the cells. After intraprostatic injections of the hybrid cells, only 2/7 mice developed microscopic tumors, with no metastases. These data suggest the presence of a gene or genes on chromosome 19 that function to suppress growth.