Possible therapeutic reversal of immune suppression in patients with metastatic melanoma by timed delivery of temozolomide chemotherapy: A pilot study

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Background: Recent evidence suggests that patients with advanced cancer exhibit an underlying anti-tumor immune response that is continuously attenuated by regulatory T cells (Treg). Depletion of Treg using conventional chemotherapy may be feasible and clinically beneficial. C-reactive protein (CRP) is reported to rise/fall with initiation/termination of the immune response, and may be a surrogate for the periodicity of Treg proliferation that could be utilized for timing of anti-proliferative therapy. Timed delivery of chemotherapy therapy based on CRP cycling may deplete Treg and yield clinical benefit. Methods: We conducted a pilot clinical for 12 patients with metastatic melanoma who underwent serial CRP measurements (every 2–3 days) for 2 weeks. The CRP oscillation cycle was identified and chemotherapy with temozolomide (200mg/m2 for 5 days, every 28 days) was initiated at the estimated peak of plasma CRP. Patients were evaluated for clinical and immune response endpoints every 8 weeks until progression. Results: All 12 patients (median age 61; 4 female; 7 with M1c disease) exhibited oscillating CRP levels with an average periodicity of 7.8 days. Only 11 patients were treated (1 patient had rapid tumor progression). The two patients who remain progression-free for >2 years (1 PR, 1 CR), were treated in the pre-peak section of the CRP cycle, distinctly separate from the other patients treated post CRP-peak (all progressed <5 months). Presented are peripheral blood immunological laboratory correlates (cellular and cytokine) to CRP oscillation. Conclusions: These data suggest that patient clinical outcome may be dependent on the timing of therapy relative to an individual patient's immune response cycle and outline the dynamic equilibrium of systemic immune homeostasis in patients with advanced melanoma. Further investigations of these observations are under way.

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A phase II trial of carboplatin (C) and nab-paclitaxel (ABI-007-nab-P) in patients with unresectable stage IV melanoma: Final data from N057E

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Background: There is increasing evidence that paclitaxel and carboplatin are clinically active in the treatment of metastatic melanoma (MM). Nab-P is an albumin-bound paclitaxel with ability to bind SPARC (secreted protein acid rich in cysteine), that is overexpressed in MM and associated with poor prognosis. This study explores the clinical activity of the combination of nab-P and C in patients (pts) with stage IV melanoma and SPARC correlatives. Methods: A parallel phase II trial was conducted in pts with unresectable stage IV melanoma, who were either chemotherapy naïve (CN) or were previously treated (PT). A treatment regimen consisting of nab-P (100 mg/m2) and C (AUC 2) was administered on days 1, 8, and 15 of a 28 day cycle. The primary aim of this study was to assess whether tumor response rate (CR + PR by RECIST) was ≤15% vs ≥35% in the CN group and ≤5% vs ≥ 20% in the PT cohort. Major eligibility criteria: ≥18 years of age, ECOG PS ≤2, adequate organ function, platinum or taxane naive, peripheral neuropathy < grade 2, and no untreated brain metastasis; no pregnant and/or nursing women. Tumor tissue was tested for SPARC and level 3 immunohistochemical staining was considered positive. Results: 76 pts (41-CN and 35 PT) enrolled from 11/2006 - 7/2007, 3 pts (2-CN, 1-PT) cancelled prior to starting treatment. The median number of cycles administered was 4 (range 1–18-CN and 1–10-PT). There were 11 (28.2%) confirmed responses (1 CR and 10 PRs) in the CN cohort (90% CI: 16.7–42.3%) and 3 (8.8%) confirmed responses (3 PRs) in the PT cohort (90% CI: 2.5–21.3%). Median PFS was 4.5 months (CN) and 4.1 months (PT). Median OS was 11.1 months (CN) and 10.9 months (PT).The most common severe toxicities in both groups (CTCAE ≥ grade 3) included neutropenia, thrombocytopenia, neuro-sensory, fatigue, nausea, and vomiting. PFS was not affected by SPARC positivity; however, based on limited data there is some evidence that OS may be longer with tumoral SPARC positivity (10.0 vs 12.8 mo; SPARC negative vs SPARC positive). Conclusions: The weekly combination of nab-P and C appears to be well tolerated with promising clinical activity as front line or salvage therapy in pts with MM. SPARC positivity may be associated with improved OS.

No significant financial relationships to disclose.

Metastatic malignant melanoma

Metastatic malignant melanoma is an incurable malignancy with extremely poor prognosis. Patients bearing this diagnosis face a median survival time of approximately 9 months with a probability of surviving 5 years after initial presentation at less than 5%. This is contrasted by the curative nature of surgical resection of early melanoma detected in the skin. To date, no systemic therapy has consistently and predictably impacted the overall survival of patients with metastatic melanoma. However, in recent years, a resurgence of innovative diagnostic and therapeutic developments have broadened our understanding of the natural history of melanoma and identified rational therapeutic targets/strategies that seem poised to significantly change the clinical outcomes in these patients. Herein we review the state-of-the-art in metastatic melanoma diagnostics and therapeutics with particular emphasis on multi-disciplinary clinical management.

N0377: Results of NCCTG phase II trial of the mTOR inhibitor RAD-001 in metastatic melanoma

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Background: RAD-001 (Everolimus) is an oral inhibitor of mammalian target of rapamycin (mTOR). Interim analysis results from a phase II study of RAD-001 in patients with metastatic melanoma (MM) were presented at ASCO 2005. This study was re-opened using a higher dose based on an improvement in the 16 week progression free survival (PFS) rate and good tolerability. Methods: A two- stage, phase II multi-institutional trial was conducted in patients with MM to assess that 16 weeks PFS rate was at least 50%. Inclusion criteria: measurable disease, ECOG performance score of 0–2. Exclusion criteria: presence of intracranial metastases, concurrent use of inducers of cytochrome 3A4 and abnormal organ function. The dose of RAD-001 in the second cohort was increased to 10 mg daily (increased from 30 mg weekly) based on evidence of safety of the higher dose. Results: Twenty-nine patients were enrolled; baseline information is available on 27. Median age was 63 yrs; 15 (56%) had >2 sites of metastatic disease. Most (48%) had stage M1c disease. PS was 0, 1 and 2 in 58%, 38% and 4%. All but 4 (15%) had received prior therapy. Grade 3 adverse events included stomatitis and fatigue (2 each), leukopenia, neutropenia, diarrhea, anorexia, dehydration, dyspnea, hyperglycemia, and hypersensitivity (1 each). Planned interim analysis was done after 20 patients were enrolled. 14 (70%) had progressed 16 weeks, failing to meet the decision rule needed (PFS >30%) to restart accrual. The median PFS for all 29 patients was 56 days. The median overall survival (OS) has not been reached. For the entire cohort of 53 pts treated on this study (at both dose levels), the median PFS, median OS were 59 and 286 days respectively. Conclusion: Interim analysis after enrollment of 20 patients at a higher dose of RAD-001 demonstrated significantly more toxicity and no added clinical efficacy. The 16 week PFS rate target was not reached, and accrual was suspended.

No significant financial relationships to disclose.

NCCTG phase I/II trial (N9943) of gemcitabine and pemetrexed in patients with biliary tract or gallbladder carcinoma: Phase II results

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Background: Gemcitabine is commonly used in patients with cholangiocarcinoma with a response rate of 20–30% and median overall survival of 6–10 months. Pemetrexed’s mechanism of action and tolerability in patients with hepatic dysfunction makes it a potential agent for cholangiocarcinoma. Methods: Patients with unresectable, previously untreated biliary tract cancers were eligible for participation. Patients received pemetrexed 500 mg/m2 IV over 10 minutes and gemcitabine 800 mg/m2 IV at 10 mg/m2/minute on days 1 and 15 of an every 4 week schedule with vitamin B12 and folate supplementation. The primary end-point is 6-month survival with a planned accrual of 59 patients. Results: 58 eligible patients are included in this analysis. 93% had metastatic disease. Median age was 61 (range: 40 - 81). Median follow-up was 6.5 months (range: 3.3 - 23.2). Median of 3 cycles of treatment was given (range: 1 - 10). Reasons for stopping treatment included disease progression (57%), adverse events (20%), refusal (17%), death on- study (4%), and other medical problems (2%). 6-month survival was 52% (95% CI: 40 - 68%). Median survival was 6.3 months (95% CI: 5.4 - 8.0 months) and median time-to-progression was 3.8 months (2.4 - 5.0). 46 of 58 patients (79%) experienced at least one grade 3+ AE (at least possible attribution), and 26 patients (45%) experienced at least one grade 4 AE (at least possible attribution), most of which were due to grade 4 neutropenia. Conclusions: This study shows similar results to what would be expected with gemcitabine alone. The addition of pemetrexed, as with other agents, has not significantly enhanced the activity of gemcitabine. Supported by NIH Grant CA25224- 18.

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No significant financial relationships to disclose.

Celiac disease and chemotherapy

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Background: Diarrhea is a common side effect of chemotherapy (CT). At times, often unpredictably, patients develop profound diarrhea during CT. Though the clinical diagnosis of celiac disease (CD) is relatively rare, (1/ 2000), the serologic prevalence is much higher (1/ 133), suggesting a large number of undiagnosed cases. Latent CD may be unmasked by stressors, such as CT. We hypothesized that undiagnosed CD may account for some cases of severe diarrhea from CT. Methods: We performed a retrospective chart review at the Mayo Clinic (1980–2006) for patients with diagnoses of cancer and CD that received CT at our center. CD cases were confirmed by biopsy (n= 25) or serologic studies. Data analyzed included severe (grade ≥ 3,) diarrhea while on CT, site of primary cancer, diagnosis of CD prior to or after CT, and specific CT agents received. Results: We identified 27 patients with CD and cancer (12 lymphoma, 6 gastrointestinal, 2 leukemia, 2 breast, 1 brain, bladder, lung, uterine, sarcoma) who received CT at our center. Fifteen were diagnosed with CD prior to receiving CT and 12 after, with the former group presumably on a gluten-free diet. One patient was excluded for lack of clinical data. Five of remaining 14 patients (35%) managed for their CD prior to CT had diarrhea, though 4 of these 5 had only mild diarrhea (gr. 1). One patient suffered gr. 3 diarrhea, though was reported to be poorly compliant with his diet. Three patients received treatment with 5- fluorouracil (5FU), and 2 had gr. 1 diarrhea. Five of the 12 patients (42%) with celiac disease undiagnosed prior to CT were reported to have diarrhea during treatment (3 gr. 4; 2 gr. 1). Of those receiving 5FU, 3 out of 4 had severe (gr. 4) diarrhea. The small numbers of patients precluded meaningful statistical analysis. Conclusion: Patients with known CD compliant with a gluten-free diet tolerated CT well. However, in a subset of undiagnosed patients, severe diarrhea developed during CT, most notably with 5FU-based regimens. We propose that when patients have diarrhea disproportionate to other effects, CD should be considered. Also, in malignancies with a high incidence of CD such as lymphoma and small bowel cancer, underlying CD should be considered before CT is given.

No significant financial relationships to disclose.

Small bowel adenocarcinoma: A review of 491 cases

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Background: Small bowel adenocarcinoma (SBA) is a rare tumor accounting for less than 2% of all GI tumors. The prognosis of advanced disease is poor. Benefits of adjuvant therapy following complete resection are uncertain. Methods: We retrospectively reviewed the records of 491 pts with primary SBA diagnosed at the Mayo Clinic from 1970–2005. Patients with ampullary and periampullary tumors were excluded. Results: 303 pts (62%) were male and the median age was 62 years. 280 (57%) of the tumors were located in the duodenum, 143 (29%) in the jejunum, 48 (10%) in the ileum and in 20 (9%) the location was not specified. Abdominal pain was the most common principal symptom occurring in 203 pts (43%), followed by anemia/GI bleeding in 104 pts (22%) and nausea/vomiting in 76 pts (16%). The most common histologic grading was 3, occurring in 224 pts (45%). 79 pts (16%) grade 4, 170 pts (35%) grade 2, with 7 (1.4%) grade 1. The TNM staging was as follows: 0: 3 (0.6%), I: 36 (7.3%), II: 133 (27.1%), III: 137 (27.9) and IV: 163 (33.2). In 18 pts (3.7%), data were insufficient for staging. The median survival for the entire cohort was 20.7 months, with 5 and 10 year survival 26% and 19% respectively. Increasing age (p < 0.0001), male sex (p = 0.026), advanced stage (p < 0.0001), grade 4 tumors (p = 0.005) and residual disease after surgery (p < 0.0001) were independently associated with shortened survival in a multivariate analysis. Neither adjuvant chemoradiation (n = 40) nor 5-FU based chemotherapy (n = 33) improved overall survival after complete resection, even after adjusting for age, sex, location, lymph node status and grade (RR 1.17, p = 0.45). This remained true for the subset of patients with resected duodenal tumors as well (RR 1.06, p = 0.83). The use of chemotherapy was associated with prolonged survival in patients with metastatic disease. The median survival and 1-year survival was 15.3 mos vs. 3.1 mos and 59% vs. 5.9% respectively (p < 0.0001), in this highly selected group. Conclusion: SBA is a rare tumor with a relatively poor prognosis. Complete resection of all disease offers the only chance of cure. The benefits of adjuvant therapy remain unknown, but chemotherapy in the metastatic setting may provide survival benefit.

No significant financial relationships to disclose.