M. E. Witt

Radiation-induced equilibrium is a balance between tumor cell proliferation and T cell-mediated killing.

Local failures following radiation therapy are multifactorial, and the contributions of the tumor and the host are complex. Current models of tumor equilibrium suggest that a balance exists between cell birth and cell death due to insufficient angiogenesis, immune effects, or intrinsic cellular factors. We investigated whether host immune responses contribute to radiation-induced tumor equilibrium in animal models. We report an essential role for immune cells and their cytokines in suppressing tumor cell regrowth in two experimental animal model systems. Depletion of T cells or neutralization of IFN-γ reversed radiation-induced equilibrium, leading to tumor regrowth. We also demonstrate that PD-L1 blockade augments T cell responses, leading to rejection of tumors in radiation-induced equilibrium. We identify an active interplay between tumor cells and immune cells that occurs in radiation-induced tumor equilibrium and suggest a potential role for disruption of the PD-L1/PD-1 axis in increasing local tumor control.

Induction chemotherapy and concurrent chemoradiotherapy for locoregionally advanced head and neck cancer: a multi-institutional phase II trial investigating three radiotherapy dose levels

BACKGROUND We hypothesized induction chemotherapy (IndCT) would improve distant control (DC) without compromising locoregional control (LRC) for locoregionally advanced head and neck cancer patients. Additionally, we systematically lowered radiotherapy (RT) doses attempting to maintain LRC while decreasing toxicity. PATIENTS AND METHODS Stages III-IV (M0) locoregionally advanced head and neck cancer patients received carboplatin/paclitaxel (Taxol) IndCT followed by four or five cycles consisting of 5 days of paclitaxel, fluorouracil, hydroxyurea, and BID RT followed by a nine day break. RT dose to gross disease (high risk), intermediate, and low-risk volumes were reduced from cohort A (n = 68): 75, 60, and 45 Gy; to cohort B (n = 64): 75, 54, and 39 Gy; then cohort C (n = 90): 72, 51, and 36 Gy. RESULTS A total of 222 patients accrued from November 1998 to September 2002. Median follow-up is 56 months. In all, 93/96/76% achieved a complete response to concurrent chemoradiotherapy (CRT) in cohort A/B/C. Three- and 5-year overall survivals (OSs) are 68% and 62%, respectively. Five-year LRC and DC are 91% and 87%, respectively. Response to IndCT predicted for OS, LRC, and time to progression (TTP). Cohort C patients had similar OS (P = 0.95), LRC, and DC, but worse (TTP) (P = 0.027). CONCLUSIONS IndCT before CRT reduces distant progression while maintaining high LRC. The cohort B schedule provides the best therapeutic ratio. A randomized trial investigating IndCT before CRT has been initiated.

A randomized phase II study of 5-fluorouracil, hydroxyurea, and twice-daily radiotherapy compared with bevacizumab plus 5-fluorouracil, hydroxyurea, and twice-daily radiotherapy for intermediate-stage and T4N0-1 head and neck cancers

INTRODUCTION We conducted a randomized phase II study to evaluate the impact of adding bevacizumab (B) to 5-fluorouracil (5-FU), hydroxyurea (HU), and radiotherapy (FHX) for intermediate-stage and select T4 head and neck squamous cell cancers (HNSCC). PATIENTS AND METHODS Eligible patients had newly diagnosed HNSCC. Randomization was 2:1 in favor of BFHX. All patients received 500 mg HU p.o. b.i.d., 600 mg/m(2)/day continuous infusion 5-FU, and b.i.d. radiotherapy with or without bevacizumab 10 mg/kg administered on day 1 of each 14-day cycle. Patients received five cycles consisting of chemoradiotherapy for 5 days followed by 9 days without therapy. RESULTS Twenty-six patients were enrolled (19 BFHX and 7 FHX). The study was halted following unexpected locoregional progression. Two-year survival was 68%; 89% treated with FHX and 58% (95% confidence interval 33% to 78%) treated with BFHX. Two-year locoregional control was 80% after chemoradiotherapy and 85% after surgical salvage. All locoregional progression occurred in T4 tumors randomized to BFHX. Two patients receiving BFHX died during therapy, and one died shortly after therapy. No catastrophic bleeding events were seen. CONCLUSIONS Locoregional progression seen in T4N0-1 tumors treated with BFHX was unexpected and led to study termination. The addition of bevacuzimab to chemoradiotherapy for HNSCC should be limited clinical trials.

A phase I–II study of concomitant chemoradiotherapy with paclitaxel (one-hour infusion), 5-fluorouracil and hydroxyurea with granulocyte colony stimulating factor support for patients with poor prognosis head and neck cancer

BACKGROUND Concomitant chemoradiotherapy is an effective treatment modality for advanced head and neck cancer, but improved regimens are needed. We sought to define the toxicities, recommended phase II dose, and outcome of a combination chemotherapy regimen with concomitant hyperfractionated radiotherapy in patients with poor prognosis cancers of the head and neck, including those having received prior curative intent radiotherapy. PATIENTS AND METHODS From 1995 until 1997, 54 patients were treated, 25 of whom had received a prior full course of radiotherapy to the head and neck. Patients were treated with 5-fluorouracil (5-FU) 600 mg/m2/day continuous infusion x 5 days (days 1-5), hydroxyurea, 500 mg p.o. bid x 11 doses (days 1-6) and paclitaxel (60-150 mg/m2) by one-hour infusion on day 2 using a dose escalation strategy. Radiotherapy was given concomitantly on days 2-6, 150 cGy bid. Each of 4-5 cycles was delivered every other week. RESULTS The MTD of paclitaxel was 100 mg/m2. The regimen was feasible; radiotherapy was delivered at a median of 7300 cGy and 83% of patients received > or = 80% planned dose intensity. Hematological toxicity, with granulocyte colony stimulating factor, was very mild. Dose limiting toxicities were mucositis and dermatitis. Despite poor prognosis, two-year survival was 45%. CONCLUSIONS The recommended phase II dose of this regimen is 5-FU 600 mg/m2/day x 120 hours (days 1-5), hydroxyurea 500 mg p.o. b.i.d. x 11 doses (days 1-6), paclitaxel 100 mg/m2 over one hour on day 2, and radiotherapy 150 cGy b.i.d. days 2-6. Concomitant chemotherapy and re-irradiation was feasible on this protocol and resulted in long-term survival in patients without other curative intent options.

Sequential induction chemotherapy and concomitant chemoradiotherapy in the management of locoregionally advanced laryngeal cancer

PURPOSE To determine overall survival, progression-free survival, rate of voice preservation, and patterns of failure in locoregionally advanced laryngeal cancer treated with induction chemotherapy with or without surgery followed by concomitant chemoradiation. BACKGROUND Locoregionally advanced laryngeal cancer has been conventionally treated with either surgery and adjuvant radiotherapy or radiotherapy alone, and clinical and functional outcomes have been poor. Chemoradiotherapy has been demonstrated to improve functional outcome and disease control over conventional treatment in recent randomized head and neck trials. PATIENTS AND METHODS Advanced head and neck cancer patients were enrolled onto two consecutive phase II studies. Induction treatment consisted of three cycles of cisplatin, 5-fluorouracil (5-FU), leucovorin, and interferon-alpha 2b (PFL-IFN) followed by surgery for residual disease. Surgical intent was to spare the larynx when possible. All patients then proceeded to concomitant chemoradiation consisting of seven or eight cycles of 5-FU, hydroxyurea, and a planned total radiotherapy dose of 7000 cGy (FHX). RESULTS A subset of thirty-two laryngeal cancer patients with predominantly stage IV disease comprises the study group for this report. Clinical CR was observed in 59% of patients following induction therapy. The median follow-up was 63.0 months for surviving patients and 44.5 months for all patients. At five years, overall survival is 47%, progression-free survival is 78%, and locoregional control is 78%. No distant failures were observed. Voice preservation with disease control was 75% at five years. Only two total laryngectomies were performed during the course of treatment and follow-up. Treatment-related toxicity accounted for two deaths. CONCLUSIONS The addition of concomitant chemoradiotherapy to induction chemotherapy for locoregionally advanced laryngeal cancer appears to increase locoregional control and survival rates. PFL-IFN-FHX resulted in high rates of disease cure and voice preservation in a group of patients that has traditionally fared poorly in both clinical and functional outcome.

Functional organ preservation with definitive chemoradiotherapy for T4 laryngeal squamous cell carcinoma

BACKGROUND Randomized trials established chemoradiotherapy as standard treatment for advanced laryngeal cancer. Patients with large-volume T4 disease (LVT4) were excluded from these trials. The purpose of this study was to report T4 laryngeal cancer patient outcome, including those with LVT4 disease, treated with chemoradiotherapy. PATIENTS AND METHODS This study is a retrospective subset analysis of 32 patients with T4 laryngeal carcinoma including LVT4 tumors treated on three consecutive protocols investigating paclitaxel (Taxol), 5-fluorouracil, hydroxyurea, and 1.5-Gy twice daily (BID) radiotherapy (TFHX). RESULTS Median follow-up is 43 months. Four-year locoregional control (LRC), disease-free survival (DFS), overall survival (OS), and laryngectomy-free survival (LFS) was 71%, 67%, 53%, and 86%, respectively. Four patients required laryngectomy for recurrent or persistent disease. Of disease-free patients with >or=1 year follow-up, 90% demonstrated normal or understandable speech. None required laryngectomy for complications. Among LVT4 patients, 4-year LRC, DFS, OS, and LFS was 71%, 65%, 56%, and 81%, respectively. Induction chemotherapy improved 4-year LRC (90% versus 46%, P = 0.03) and DFS (84% versus 42%, P = 0.03). CONCLUSIONS Promising control and functional outcomes are achieved with TFHX for T4 laryngeal patients. LVT4 disease had outcomes similar to patients with less advanced disease treated on Radiation Therapy Oncology Group 91-11. Induction chemotherapy improved outcomes, warranting further investigation.

Chemoreirradiation for recurrent salivary gland malignancies

BACKGROUND AND PURPOSE To report our experience in treating recurrent salivary gland malignancies using concurrent chemotherapy and reirradiation. MATERIALS AND METHODS Between 1986 and 2007, 14 patients with locoregionally recurrent salivary gland cancer underwent maximal surgical resection followed by adjuvant 5-fluorouracil and hydroxyurea-based chemotherapy concurrently with 1.5Gy twice daily or 2Gy daily reirradiation. Each cycle consisted of chemoreirradiation for 5 consecutive days followed by a 9-day break. The median reirradiation dose was 66Gy (R 30-72Gy) after a mean radiation treatment interval of 48 months. RESULTS The median follow-up for all patients was 18 months (R 2-125 months) and 41 months for survivors. The parotid gland (n=6) and minor salivary glands (n=6) were involved more commonly than the submandibular gland (n=2). Locoregional control at 1 and 3years was 72.2% and 51.6%, respectively. Actuarial overall survival at 3 and 5 years was 35.7% and 26.8%, respectively. Tracheostomies and feeding tubes were placed in 2 and 8 patients, respectively. Six patients had feeding tubes at last follow-up or death. CONCLUSIONS Concurrent chemotherapy and reirradiation for recurrent salivary malignancies result in promising locoregional control for patients with recurrent salivary gland malignancies.

Chemoradiotherapy for locoregionally advanced squamous cell carcinoma of the base of tongue

Our aim was to report the outcomes of base of tongue cancers treated with chemoradiotherapy.

Phase II trial of pemetrexed-based induction chemotherapy followed by concomitant chemoradiotherapy in previously irradiated patients with squamous cell carcinoma of the head and neck

BACKGROUND Concurrent chemoreirradiation therapy (CRRT) offers a therapeutic option for patients with locoregionally recurrent squamous cell carcinoma of the head and neck (SCCHN). We hypothesized that response to induction chemotherapy (IC) would improve outcome and predict increased survival. PATIENTS AND METHODS Subjects with recurrent SCCHN not amenable to standard therapy were eligible. IC consisted of two 28-day cycles of gemcitabine and pemetrexed on days 1 and 14, followed by surgical resection, if appropriate, and/or CRRT consisting of carboplatin, pemetrexed, and single daily fractionated radiotherapy. RESULTS Thirty-five subjects were enrolled, 31 were assessable for response, with 11 responders [response rate = 35%; 95% confidence interval (CI) 19.2-54.6]. Among 24 subjects who started CRRT, 11 were assessable for radiographic response, 4 complete response, 2 partial response, and 5 progressive disease. Median progression-free survival and overall survival (OS) were 5.5 months (95% CI 3.6-8.3) and 9.5 months (95% CI 7.2-15.4), respectively. One-year OS was 43% (95% CI 26% to 58%). Subjects who responded to IC had improved survival (P = 0.02). Toxic effects included mucositis, dermatitis, neutropenia, infection, hemorrhage, dehydration, and pain. CONCLUSIONS The combination of pemetrexed plus gemcitabine was active and well tolerated in recurrent SCCHN. Response to IC may help stratify prognosis and offer an objective and dynamic metric in recurrent SCCHN patients being considered for CRRT.

A phase I dose escalation study of Ad GV.EGR.TNF.11D (TNFerade™ Biologic) with concurrent chemoradiotherapy in patients with recurrent head and neck cancer undergoing reirradiation

BACKGROUND AdGV.EGR.TNF.11D (TNFerade™ Biologic) is a replication-deficient adenoviral vector expressing human tumor necrosis factor alpha (TNF-α) under the control of the chemoradiation-inducible EGR-1 promoter. TNF-α has been shown to function as a radiation sensitizer. We conducted a phase I dose escalation study to determine the maximum tolerated dose (MTD) and dose-limiting toxicity (DLT) of TNFerade™ Biologic, when added to chemoradiotherapy in poor prognosis patients with recurrent, previously irradiated head and neck cancer (HNC). METHODS TNFerade™ Biologic was injected intratumorally on day 1 of each 14-day cycle and dose-escalated in log increments from 4 × 10(9) to 4 × 10(11) PU. Daily radiation, infusional 5-fluorouracil (5-FU), and hydroxyurea were given on days 1-5 for seven cycles (FHX). Tumor biopsies were obtained before, during, and after treatment. RESULTS Fourteen patients were treated. DLT was reached at a dose level of 3 (4 × 10(11) PU) with three thrombotic events. The response rate was 83.3%. The median survival was 9.6 months. One patient (7.1%) remained alive 3 years after treatment. Biopsies were obtained in 90% of patients. Nearly all tumors expressed adenovirus receptors, TNF-α, and TNF-α receptors. Adenoviral DNA was detected in three biopsies from one patient. CONCLUSIONS TNFerade™ Biologic can be safely integrated with FHX chemoradiotherapy at an MTD of 4 × 10(10) PU. Monitoring for thrombotic events is indicated.