Development of leptomeningeal carcinomatosis (LC) in advanced prostate cancer patients: Characteristics of six cases in a single institution

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Background: In the past months, we have noticed an increasing number of leptomeningeal carcinomatosis (LC) in patients known for advanced prostate cancer (PC). This complication has only been reported in a few patients.

Methods: We identified and reviewed the charts of all patients known for advanced PC who later developed LC. We report their characteristics as well as survival.

Results: Between March 2009 and April 2010, we identified 6 patients known for advanced PC that showed evidence of LC (median time from diagnosis of prostate cancer to development of LC, 55.8 months). Disease was already metastatic to other sites in all of them, and all had previously showed evidence of castrate refractory prostate cancer (CRPC). All patients maintained LHRH agonist therapy and were treated with prednisone once they showed evidence of CRPC. Most had also been treated with docetaxel (n=5), zoledronic acid (n=4; the remaining 2 patients received either zoledronic acid or denosumab as part of a protocol) and/or other (dasatinib/placebo as part of a protocol, n=1; sunitinib as part of a protocol, n=1). LC was diagnosed a median of 21.2 months after evidence of CRPC, based on clinical findings (cranial nerve[s] involvement [n=6] and nausea and/or ataxia [n=2]) and magnetic resonance imaging (MRI). 2 patients underwent lumbar puncture (negative results). Treatment administered for LC included dexamethasone (n=1), radiation therapy (n=1), or both (n=2). Two patients with poor performance status did not receive any treatment. All patients assessable for response (n=3) showed a partial improvement in their symptoms, but not complete resolution. Median overall survival from development of CRPC and from diagnosis of LC is 23.9 months and 2.7 months, respectively.

Conclusions: LC is a newly described site of metastasis in patients with advanced CRPC. It is associated with a late onset and a very poor prognosis.

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SUNCAP, a phase II study with sunitinib and capecitabine in patients with metastatic colorectal cancer (MCRC) refractory to previous treatment with 5FU/irinotecan/oxaliplatin

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Background: Patients (pts) with MCRC refractory/resistant to Irinotecan and Oxaliplatin have a poor prognosis. Sunitinib is an oral TKI that selectively inhibits the VEGFR 1, 2, 3, PDGFR and FLT3, CSF-1R, RET. Phase II studies with single agent sunitinib in patients with MCRC did not demonstrate a meaningful ORR but showed acceptable safety profile and warranted further study.

Methods: We conducted a phase II escalating dose of sunitinib (S) and capecitabine (C) to assess the efficacy of this oral treatment given on a 2 wks every 3 wks schedule, (level 0, S: 37,5 mg, C: 2,000mg/m2, level +1, S: 50 mg, C: 2,000 mg/m2, level +2, S: 50 mg, C: 2,500 mg/m2 and level -1:S: 25 mg, C: 1,500 mg/m2. Treatment was initiated at level 0 and increased at level +1 and +2 at cycle 3 and 5 if no grade 2/3 toxicity was observed. Between 02.2009 and 06.2010, 15 pts previously exposed to oxaliplatin/irinotecan/bevazizumab were enrolled, all of them had progressive disease at the time of study entry. Primary objective was ORR. Treatment was given until PD or unacceptable toxicity.

Results: Pts characteristics were: sex: 12M/3F, median age: 65 years [41-75], primary tumors: colon: 13, rectum: 2, ECOG PS 0/1: 8/7, median nb of metastatic sites: 3, KRAS status: WT/MT/Unknown: 1/9/5. Escalating to level +1:53%, level +2: 7%. Median nb of cycles received/pt: 5. All pts were evaluable for toxicity (tox): SAEs: 40%, any tox. grade 1/2/3(%): 93/60/ 40. Neutropenia gr. 1/2/3(%): 13/13/7, thrombocytopenia gr.1/2/3(%): 13/20/7. Fatigue gr.1/2/3(%): 27/20/7. Nausea gr.1: 27%. Diarrhea gr.1: 13%. Hand foot syndrome gr. 1/2/3 (%): 13/13/27. Mucositis gr. 1/2/3(%): 7/20/7. Hypertension gr.2: 13%. Thyroïd gr.1: 27%. ORR (CR+PR): 0%, confirmed SD: 7/15: 47%, PD: 8/15: 53%. Median PFS: 137 days [95%CI: 112-162], median OS: 291 days [95%CI: 99-482].

Conclusions: In this heavily pretreated patients, sunitinib in combination with capecitabine appears feasible, with acceptable toxicity. 47% of patients had a confirmed stable disease. Although no objective response was observed, the high level of stable disease may suggest a role of this combination for maintenance therapy.

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