Long-Term Survival after Complete Surgical Resection and Adjuvant Immunotherapy for Distant Melanoma Metastases.

BACKGROUND: This phase III study was undertaken to evaluate the efficacy of an allogeneic whole-cell vaccine (Canvaxin™) plus bacillus Calmette-Guerin (BCG) after complete resection of stage IV melanoma. METHODS: After complete resection of ≤5 distant metastases, patients were randomly assigned to BCG+Canvaxin (BCG/Cv) or BCG+placebo (BCG/Pl). The primary endpoint was overall survival (OS); secondary endpoints were disease-free survival (DFS), and immune response measured by skin test (ClinicalTrials.gov identifier: NCT00052156). RESULTS: Beginning in May 1998, 496 patients were randomized. In April 2005, the Data Safety Monitoring Board recommended stopping enrollment due to a low probability of efficacy. At that time, median OS and 5-year OS rate were 38.6 months and 44.9%, respectively, for BCG/Pl versus 31.4 months and 39.6% in the BCG/Cv group (hazard ratio (HR), 1.18; p = 0.250). Follow-up was extended at several trial sites through March 2010. Median OS and 5-year and 10-year survival was 39.1 months, 43.3 and 33.3%, respectively, for BCG/Pl versus 34.9 months, 42.5 and 36.4%, in the BCG/Cv group (HR 1.053; p = 0.696). Median DFS, 5- and 10-year DFS were 7.6 months, 23.8 and 21.7%, respectively, for BCG/Pl versus 8.5 months, 30.0%, and 30.0%, respectively, for the BCG/Cv group (HR 0.882; p = 0.260). Positive DTH skin testing correlated with increased survival. DISCUSSION: In this, the largest study of postsurgical adjuvant therapy for stage IV melanoma reported to date, BCG/Cv did not improve outcomes over BCG/placebo. Favorable long-term survival among study patients suggests that metastasectomy should be considered for selected patients with stage IV melanoma.

BRAF inhibition for advanced locoregional BRAF V600E mutant melanoma: a potential neoadjuvant strategy.

Selective BRAF inhibitors (BRAFi) yield objective responses in 50% of patients with metastatic BRAF V600E mutant melanoma. Adding an MEK inhibitor increases this response rate to 70%. Limited data are available on the outcomes of unresectable stage III patients, and it remains unclear whether BRAF-targeted therapy can be utilized as a neoadjuvant strategy. Data on patients with advanced locoregional BRAF V600E mutant melanoma treated with BRAF-targeted therapy at Moffitt Cancer Center were analyzed to determine response rates, subsequent resection rates after tumor downsizing, pathologic responses, and patient survival. Fifteen patients with locoregional disease treated with BRAF-targeted therapy, either BRAFi alone (vemurafenib; 11 patients) or a combination of BRAFi and an MEK inhibitor (dabrafenib plus trametinib or placebo; four patients), were identified. The median age was 50 years; the median follow-up was 25.4 months. The median BRAF-targeted therapy treatment duration was 6.0 months (range 1.2-29.4 months). Response Evaluation Criteria In Solid Tumors-based evaluation demonstrated objective response in 11 patients (73.3%). Six patients underwent resection of the remaining disease after therapy. Pathological analysis showed complete pathologic response (n=2), partial pathologic response (n=2), or no pathologic response (n=2). Four of six patients undergoing surgery have been alive for more than 2 years, including three patients currently free from active disease. No complications attributable to BRAF-targeted therapy were observed in the perioperative period. Dose reduction or discontinuation because of toxicities occurred in 10/15 patients. Neoadjuvant BRAF-targeted therapy may be effective in advanced locoregional BRAF V600E mutant melanoma patients in increasing resectability, yielding pathological responses, and achieving prolonged survival.

Both tumor depth and diameter are predictive of sentinel lymph node status and survival in Merkel cell carcinoma.

BACKGROUND: The purposes of this study were 1) to determine the impact of primary tumor-related factors on the prediction of the sentinel lymph node (SLN) status and 2) to identify clinical and pathologic factors associated with survival in Merkel cell carcinoma (MCC). METHODS: An institutional review board-approved, retrospective review of patients with MCC treated between 1988 and 2011 at a single center was performed. Patients were categorized into 5 groups: 1) negative SLN, 2) positive SLN, 3) clinically node-negative but SLN biopsy not performed, 4) regional nodal disease without a known primary tumor, and 5) primary MCC with synchronous clinically evident regional nodal disease. Factors predictive of the SLN status were analyzed with logistic regressions, and overall survival (OS) and disease-specific survival (DSS) were analyzed with Cox models and competing risk models assuming proportional hazards, respectively. RESULTS: Three hundred seventy-five patients were analyzed, and 70% were male; the median age was 75 years. The median tumor diameter was 1.5 cm (range, 0.2-12.5 cm), and the median tumor depth was 4.8 mm (range, 0.3-45.0 mm). One hundred ninety-one patients underwent SLN biopsy, and 59 (31%) were SLN-positive. Increasing primary tumor diameter and increasing tumor depth were associated with SLN positivity (P = .007 and P = .017, respectively). Age and sex were not associated with the SLN status. Immunosuppression, increasing tumor diameter, and increasing tumor depth were associated with worse OS (P = .007, P = .003, and P = .025, respectively). DSS differed significantly by group and was best for patients with a negative SLN and worst for those with primary MCC and synchronous clinically evident nodal disease (P = .018). CONCLUSION: For patients with MCC, increasing primary tumor diameter and increasing tumor depth are independently predictive of a positive SLN, worse OS, and worse DSS. Tumor depth should be routinely reported when primary MCC specimens are being evaluated histopathologically.

Safety, correlative markers, and clinical results of adjuvant nivolumab in combination with vaccine in resected high-risk metastatic melanoma.

PURPOSE: The anti-programmed death-1 (PD-1) antibody nivolumab (BMS-936558) has clinical activity in patients with metastatic melanoma. Nivolumab plus vaccine was investigated as adjuvant therapy in resected stage IIIC and IV melanoma patients. EXPERIMENTAL DESIGN: HLA-A*0201 positive patients with HMB-45, NY-ESO-1, and/or MART-1 positive resected tumors received nivolumab (1 mg/kg, 3 mg/kg, or 10 mg/kg i.v.) with a multi-peptide vaccine (gp100, MART-1, and NY-ESO-1 with Montanide ISA 51 VG) every 2 weeks for 12 doses followed by nivolumab maintenance every 12 weeks for 8 doses. Primary objective was safety and determination of a maximum tolerated dose (MTD). Secondary objectives included relapse-free survival (RFS), overall survival (OS), and immunologic correlative studies. RESULTS: Thirty-three patients were enrolled. Median age was 47 years; 55% were male. Two patients had stage IIIC disease; 31 patients had stage IV disease. Median follow-up was 32.1 months. MTD was not reached. Most common related adverse events (>40%) were vaccine injection site reaction, fatigue, rash, pruritus, nausea, and arthralgias. Five related grade 3 adverse events [hypokalemia (1), rash (1), enteritis (1), and colitis (2)] were observed. Ten of 33 patients relapsed. Estimated median RFS was 47.1 months; median OS was not reached. Increases in CTLA-4(+)/CD4(+), CD25(+)Treg/CD4(+), and tetramer specific CD8(+) T-cell populations were observed with treatment (P < 0.05). Trends for lower baseline myeloid-derived suppressor cell and CD25(+)Treg/CD4(+) populations were seen in nonrelapsing patients; PD-L1 tumor status was not significantly associated with RFS. CONCLUSIONS: Nivolumab with vaccine is well tolerated as adjuvant therapy and demonstrates immunologic activity with promising survival in high-risk resected melanoma, justifying further study.

Postoperative concurrent chemotherapy and radiotherapy for high-risk cutaneous squamous cell carcinoma of the head and neck.

BACKGROUND: Despite resection followed by adjuvant radiotherapy, high-risk cutaneous squamous cell carcinomas of the head and neck region (SCCHN) often recur. Because adjuvant concurrent chemoradiation reduces recurrence among high-risk mucosal SCCHN, we sought to understand its efficacy among high-risk cutaneous SCCHN. METHODS: We conducted a retrospective cohort study of patients with cutaneous SCCHN who underwent adjuvant radiation or concurrent chemoradiation. Patients must have had stage III/IV with high-risk features, including metastatic involvement of ≥2 lymph nodes, positive margins, or extracapsular invasion. RESULTS: There were 61 patients: 27 (44%) received adjuvant radiation and 34 (56%) received adjuvant chemoradiation. The median recurrence-free survivals were 15.4 and 40.3 months, respectively. Adjuvant chemoradiation significantly decreased the risk of recurrence or death in a multivariable analysis: hazard ratio (HR) 0.31 (p = .01). However, a difference in overall survival was not found. CONCLUSION: For high-risk cutaneous SCCHN, adjuvant chemoradiation was associated with a better recurrence-free survival than adjuvant radiation alone.

Intensity-modulated radiation therapy as primary treatment for oropharyngeal squamous cell carcinoma.

BACKGROUND: Over the past decade, intensity-modulated radiation therapy (IMRT) has gained widespread use in the treatment of head and neck cancer. METHODS: All patients with squamous cell carcinoma of the oropharynx treated with primary IMRT with or without chemotherapy over a 5-year period were reviewed. Outcomes and morbidity were analyzed and compared with previously published data. RESULTS: In all, 170 patients were included in the analysis. The 3-year local control, locoregional control, disease-free survival, and overall survival rates were 92%, 91%, 80%, and 87%, respectively. Feeding tubes were present in 55% of patients during treatment, but remained in only 1% 2 years following treatment. CONCLUSIONS: This study confirms that IMRT yields excellent treatment outcomes for oropharyngeal carcinoma. Although acute toxicity remains a problem, late toxicity rates are low and long-term feeding tube dependence is rare compared with conventional radiation therapy.

Squamous cell carcinoma with rhabdoid phenotype of skin/soft tissue in a transplant patient: an exceptional case and review of the literature.

Squamous cell carcinoma with rhabdoid features (SCCRF) is a very rare and unusual cutaneous tumor. Here, we report an extraordinary case diagnosed by fine needle aspiration biopsy, in a 66-year-old man, status post multiple organ transplantation. The patient presented with a large ulcerating fungating mass in his forearm that had all the light microscopic and immunohistochemical features of a SCCRF. Previously six cases of SCCRF phenotype diagnosed by surgical pathology have been reported. This is the first case diagnosed cytologically. A review of the literature with emphasis on the differential diagnoses of such unusual rhabdoid-like tumors in fine-needle aspiration biopsy and the potential molecular mechanism for rhabdoid phenotype in transplant patients are discussed.

Chemotherapy of squamous cell carcinoma of the skin.

The role of systemic chemotherapy with cytotoxic agents in squamous cell carcinoma of the skin remains uncertain. A number of agents in combination have been reported to induce high rates of remission, either alone or as a component of a multidisciplinary management plan. Fragmentary data suggest that the most benefit is achieved when chemotherapy is applied to patients with advanced local disease not easily treated with surgery either due to location (eg, on the face) or comorbidity. Concurrent chemoradiation has been recommended for the control of extensive lymph node involvement as a result of experience derived from similar studies in patients with squamous cell carcinomas of the head and neck, cervix, and anus. No standard treatment of metastatic disease has been formulated, although combinations of cisplatin with 5-fluorouracil (5-FU), doxorubicin, or bleomycin have demonstrated some degree of efficacy, achieving complete responses (CRs) in some cases. Clearly, the relative rarity of patients with high-risk, potentially fatal, squamous cell carcinoma of the skin has limited prospective efforts to define ideal management. As our awareness of the increasing numbers of such problem patients becomes clear, hopefully more efforts will be forthcoming.

Recent advances in the understanding of the genetics, etiology, and treatment of Merkel cell carcinoma.

Merkel cell carcinoma (MCC) is a highly aggressive skin malignancy. The growing incidence and recognition of this cancer in elderly or immunosuppressed individuals suggests that it is becoming an increasing clinical challenge. MCC recently has been demonstrated to have a probable viral pathogenesis related to a novel member of the polyomavirus (termed Merkel cell polyomavirus [MCV]). The molecular pathogenesis of viral carcinogenesis is currently being worked out in MCC. Current diagnostic and therapeutic strategies are discussed, with an eye toward the future development of molecularly targeted treatments.

A phase 2 trial of bortezomib followed by the addition of doxorubicin at progression in patients with recurrent or metastatic adenoid cystic carcinoma of the head and neck: a trial of the Eastern Cooperative Oncology Group (E1303).

BACKGROUND: Bortezomib, an inhibitor of the 26S proteasome and NF-κB, may have antitumor activity in adenoid cystic carcinoma (ACC). Preclinical studies have shown synergy between bortezomib and doxorubicin. METHODS: Eligibility criteria included incurable ACC, any number of prior therapies but without an anthracycline, unidimensionally measurable disease, Eastern Cooperative Oncology Group performance status 0-2, and ejection fraction within normal limits. Patients with stable disease for ≥9 months were excluded. Patients received bortezomib 1.3 mg/m(2) by intravenous (IV) push on Days 1, 4, 8, and 11, every 21 days until progression. Doxorubicin 20 mg/m(2) IV on Days 1 and 8 was added at the time of progression. RESULTS: Twenty-five patients were enrolled, of whom 24 were eligible; the most common distant metastatic sites were the lung (n = 22) and the liver (n = 7). There was no objective response with single-agent bortezomib; best response was stable disease in 15 (71%) of 21 evaluable patients. The median progression-free survival and overall survival were 6.4 months and 21 months, respectively. Of 10 evaluable patients who received bortezomib plus doxorubicin, 1 had a partial response, and 6 had stable disease. The most frequent toxicity with bortezomib was grade 3 sensory neuropathy (16%). With bortezomib plus doxorubicin, serious toxicities seen more than once were grade 3-4 neutropenia (n = 3) and grade 3 anorexia (n = 2). CONCLUSIONS: Bortezomib was well tolerated and resulted in disease stabilization in a high percentage of patients but no objective responses. The combination of bortezomib and doxorubicin was also well tolerated and may warrant further investigation in ACC.

Changes in dendritic cell phenotype after a new high-dose weekly schedule of interleukin-2 therapy for kidney cancer and melanoma.

High-dose intravenous interleukin-2 (IL-2) therapy (14 doses/course, 2 courses/cycle) for metastatic melanoma or kidney cancer induces infrequent, although major responses. In this trial, we evaluated a new schedule (dose of 600,000 IU/kg, 8 h between doses, 5 doses/course, 4 courses at weekly intervals/cycle) of high-dose IL-2, in which we inserted more planned breaks while maintaining high cumulative dose delivery, and investigated the relationship between dendritic cells (DC) and response to treatment. Target dose delivery was attained: median IL-2 cumulative dose per patient was 11.4 and 10.8 million units/kg (cycles 1 and 2, respectively). Major responses were observed in patients with kidney cancer (n=20; 3 complete and 2 partial responses) and melanoma (n=16; 1 partial response). Adverse events appeared comparable with those typically associated with high-dose IL-2. From this data set, we introduce the hypothesis-generating observation that patients who had more favorable outcomes had high pretreatment DC-to-myeloid-derived suppressor cell (MDSC) ratios, similar to the ratio observed in healthy individuals. However, even in patients with the most favorable outcome, after treatment, there were IL-2-induced changes in the DC-to-MDSC ratio, specifically increases in MDSCs. This modified IL-2 schedule is a feasible option, with a more uniform dose delivery over the treatment cycle, a similar toxicity profile, and observed complete, durable response in patients with renal cancer. Pretreatment assessment of DC phenotypic or maturational status may be a starting point to predicting response to high-dose IL-2 cytokine immunotherapy in patients with melanoma and kidney cancer.

A phase II trial of imatinib mesylate in merkel cell carcinoma (neuroendocrine carcinoma of the skin): A Southwest Oncology Group study (S0331).

BACKGROUND: Imatinib mesylate (Gleevec) was evaluated as a treatment for Merkel cell carcinoma (MCC, neuroendocrine carcinoma of the skin) based on the identification of strong c-KIT staining of these neoplasms. METHODS: Eligibility included patients with measurable metastatic or unresectable MCC, c-KIT (CD117) expression and a Zubrod performance status of 0 to 2. Imatinib 400 mg daily was administered orally in 28-day cycles to 23 patients. RESULTS: Overall, imatinib was well tolerated with grade 1 or 2 nausea, diarrhea, and hematologic toxicity as the most frequent side effects. A partial response was seen in 1 patient (4%; 95% CI: 0%-22%). Median progression-free survival was 1 month (95% CI: 1-2 months). Median overall survival was 5 months (95% CI: 2-8 months). One patient achieved a partial response and another had prolonged disease stabilization while receiving treatment. CONCLUSIONS: The majority of patients progressed rapidly within 1 to 2 cycles of treatment. The observed progression-free survival and overall survival were not adequate to conclude that this agent was active in advanced MCC, and thus the planned second stage of patient accrual was not opened.

Outcomes of postoperative concurrent chemoradiotherapy for locally advanced major salivary gland carcinoma.

OBJECTIVE: To investigate the potential value of postoperative concurrent chemoradiation among patients with high-risk salivary gland carcinomas. DESIGN: Case control study based on retrospective medical record review. SETTING: A tertiary care comprehensive cancer center. PATIENTS: A total of 24 patients, 12 with major salivary gland carcinoma who were treated with postoperative concurrent chemoradiotherapy from 1998 to 2007 (chemoradiation group), and a control group of 12 patients treated with postoperative radiation alone. MAIN OUTCOME MEASURES: Overall survival, progression-free survival, toxic effects. RESULTS: All but 1 patient had stage III or IV disease; close or positive surgical margins were identified in 20 patients (83%). The median radiation dose was 63 Gy. In the chemoradiation group, platinum-based regimens were used in all. Treatment was well tolerated, but toxic effects, predominantly hematologic, were increased in the chemoradiation group. To date, 8 patients have died; the median overall survival was 53 months. The overall survival in the chemoradiation group was significantly better than in the radiation-alone group: 3-year survival rates were 83% and 44%, respectively (P = .05). CONCLUSIONS: Locally advanced or high-grade salivary gland carcinomas follow an aggressive clinical course. Based on our limited experience, postoperative chemoradiation with a platinum-based regimen seems to be effective in selected patients and warrants further investigation.

Potentiation of a topoisomerase I inhibitor, karenitecin, by the histone deacetylase inhibitor valproic acid in melanoma: translational and phase I/II clinical trial.

PURPOSE: The novel topoisomerase I inhibitor karenitecin (KTN) shows activity against melanoma. We examined whether histone deacetylase inhibition could potentiate the DNA strand cleavage, cytotoxicity as well as the clinical toxicity, and efficacy of KTN in melanoma. EXPERIMENTAL DESIGN: Apoptosis, COMET, and xenograft experiments were carried out as described previously. A phase I/II trial of valproic acid (VPA) and KTN was conducted in patients with stage IV melanoma, with any number of prior therapies, Eastern Cooperative Oncology Group performance status 0-2, and adequate organ function. RESULTS: VPA pretreatment potentiated KTN-induced apoptosis in multiple melanoma cell lines and in mouse A375 xenografts. VPA increased KTN-induced DNA strand breaks. In the phase I/II trial, 39 patients were entered, with 37 evaluable for toxicity and 33 evaluable for response. Somnolence was the dose-limiting toxicity. The maximum tolerated dose for VPA was 75 mg/kg/d; at maximum tolerated dose, serum VPA was approximately 200 microg/mL (1.28 mmol/L). At the dose expansion cohort, 47% (7 of 15) of patients had stable disease; median overall survival and time to progression were 32.8 and 10.2 weeks, respectively. Histone hyperacetylation was observed in peripheral blood mononuclear cells at maximum tolerated dose. CONCLUSION: VPA potentiates KTN-induced DNA strand breaks and cytotoxicity. VPA can be combined at 75 mg/kg/d for 5 days with full-dose KTN without overlapping toxicities. In metastatic poor prognosis melanoma, this combination is associated with disease stabilization in 47% of patients. Further testing of this combination appears warranted.

Prognostic factors for survival after salvage reirradiation of head and neck cancer.

PURPOSE: Patients who develop recurrent or new primary head and neck cancer in a previously irradiated site have poor prognosis. Reirradiation is a treatment option, although it is associated with substantial toxicities. We investigated potential prognostic factors, including comorbidity and pre-existing organ dysfunction, for survival after reirradiation. METHODS: Institutional electronic records of patients treated with reirradiation between January 1998 and 2008 were reviewed. Comorbidity was assessed by Charlson index and Adult Comorbidity Evaluation-27 (ACE-27) grading. Organ dysfunction was defined as feeding tube dependency, functioning tracheostomy, or soft tissue defect. RESULTS: There were 103 patients, including 46 patients who underwent salvage surgery before reirradiation. Median progression-free and overall survivals were 12.1 months (95% CI, 9.7 to 16.6) and 19.3 months (95% CI, 13.9 to 29.9), respectively. Significant comorbidity was present in 36% of patients by Charlson index and 24% by ACE-27. Baseline organ dysfunction was present in 37% of patients. Median overall survivals were 5.5 months among those with both organ dysfunction and comorbidity per Charlson index, and 4.9 months per ACE-27, compared with 59.6 and 44.2 months, respectively, among the patients with neither organ dysfunction nor comorbidity (P < .001 and < .001). Other independent prognostic factors were interval from previous radiation, recurrent tumor stage, tumor bulk at reirradiation, and reirradiation dose. A nomogram to predict the probability of death within 24 months after reirradiation was developed (concordance index = 0.75). CONCLUSION: Comorbidity and pre-existing organ dysfunction are among several important prognostic factors for patients undergoing reirradiation. For those with both comorbidity and organ dysfunction, reirradiation largely serves as a palliative therapy.

Phase I trial of interleukin-12 plasmid electroporation in patients with metastatic melanoma.

PURPOSE: Gene-based immunotherapy for cancer is limited by the lack of safe, efficient, reproducible, and titratable delivery methods. Direct injection of DNA into tissue, although safer than viral vectors, suffers from low gene transfer efficiency. In vivo electroporation, in preclinical models, significantly enhances gene transfer efficiency while retaining the safety advantages of plasmid DNA. PATIENTS AND METHODS: A phase I dose escalation trial of plasmid interleukin (IL)-12 electroporation was carried out in patients with metastatic melanoma. Patients received electroporation on days 1, 5, and 8 during a single 39-day cycle, into metastatic melanoma lesions with six 100-mus pulses at a 1,300-V/cm electric field through a penetrating six-electrode array immediately after DNA injection. Pre- and post-treatment biopsies were obtained at defined time points for detailed histologic evaluation and determination of IL-12 protein levels. RESULTS: Twenty-four patients were treated at seven dose levels, with minimal systemic toxicity. Transient pain after electroporation was the major adverse effect. Post-treatment biopsies showed plasmid dose proportional increases in IL-12 protein levels as well as marked tumor necrosis and lymphocytic infiltrate. Two (10%) of 19 patients with nonelectroporated distant lesions and no other systemic therapy showed complete regression of all metastases, whereas eight additional patients (42%) showed disease stabilization or partial response. CONCLUSION: This report describes the first human trial, to our knowledge, of gene transfer utilizing in vivo DNA electroporation. The results indicated this modality to be safe, effective, reproducible, and titratable.

Phenotypic and functional analysis of dendritic cells and clinical outcome in patients with high-risk melanoma treated with adjuvant granulocyte macrophage colony-stimulating factor.

PURPOSE: Granulocyte macrophage colony-stimulating factor (GM-CSF) can induce differentiation of dendritic cells (DCs) in preclinical models. We hypothesized that GM-CSF-stimulated DC differentiation may result in clinical benefit in patients with high-risk melanoma. PATIENTS AND METHODS: We conducted a prospective trial in patients with high-risk (stage III B/C, IV), resected melanoma, with GM-CSF 125 microg/m(2)/d administered for 14 days every 28 days. Patients underwent clinical restaging every four cycles, with DC analysis performed at baseline and at 2, 4, 8, and 12 weeks. RESULTS: Of 42 patients enrolled, 39 were assessable for clinical outcome and DC analysis. Median overall survival was 65 months (95% CI, 43 to 67 months) and recurrence-free survival was 5.6 months (95% CI, 3 to 11 months). GM-CSF treatment caused an increase in mature DCs, first identified after 2 weeks of treatment, normalizing by 4 weeks. Patients with decreased DCs at baseline had significant increases in DC number and function compared with those with "normal" parameters at baseline. No change was observed in the number of myeloid-derived suppressor cells (MDSCs). Early recurrence (< 90 days) correlated with a decreased effect of GM-CSF on host DCs, compared with late or no (evidence of) recurrence. CONCLUSION: GM-CSF treatment was associated with a transient increase in mature DCs, but not MDSCs. Greater increase of DCs was associated with remission or delayed recurrence. The prolonged overall survival observed warrants further exploration.

Phase I trial of histone deacetylase inhibition by valproic acid followed by the topoisomerase II inhibitor epirubicin in advanced solid tumors: a clinical and translational study.

PURPOSE: To determine the safety, toxicity, and maximum-tolerated dose of a sequence-specific combination of the histone deacetylase inhibitor (HDACi), valproic acid (VPA), and epirubicin in solid tumor malignancies and to define the clinical feasibility of VPA as an HDACi. PATIENTS AND METHODS: Patients were treated with increasing doses of VPA (days 1 through 3) followed by epirubicin (day 3) in 3-week cycles. The study evaluated pharmacokinetic and pharmacodynamic end points, toxicities, and tumor response. RESULTS: Forty-eight patients were enrolled, and 44 received at least one cycle of therapy. Patients (median age, 54 years; range, 39 to 78 years) received the following doses of VPA: 15, 30, 45, 60, 75, 90, 100, 120, 140, and 160 mg/kg/d. Dose-limiting toxicities were somnolence (n = 1), confusion (n = 3), and febrile neutropenia (n = 1). No exacerbation of epirubicin-related toxicities was observed. Partial responses were seen across different tumor types in nine patients (22%), and stable disease/minor responses were seen in 16 patients (39%), despite a median number of three prior regimens (range, zero to 10 prior regimens). Patients received a median number of four treatment cycles (range, one to 10 cycles), and treatment was stopped after reaching maximal epirubicin doses rather than progression in 13 (32%) of 41 patients patients. Total and free VPA plasma concentrations increased linearly with dose and correlated with histone acetylation in peripheral-blood mononuclear cells. CONCLUSION: The maximum-tolerated dose and recommended phase II dose was VPA 140 mg/kg/d for 48 hours followed by epirubicin 100 mg/m2. Sustained plasma concentrations of VPA exceeding those required for in vitro synergy were achieved with acceptable toxicity. Noteworthy antitumor activity was observed in heavily pretreated patients and historically anthracycline-resistant tumors.