Intensive concurrent chemoradiotherapy for head and neck cancer with 5-Fluorouracil- and hydroxyurea-based regimens: reversing a pattern of failure

Induction Therapy for Locally Advanced Head and Neck Squamous Cell Carcinoma

The optimal approach to locally advanced head and neck squamous cell carcinoma (LAHNSCC) treatment remains controversial. For non-resectable LAHNSCC, the clinical interest of induction chemotherapy followed by concurrent chemoradiotherapy (CCRT) or radiotherapy has been questioned. With the approval of immunotherapy and targeted therapy for this disease, treatment options have become more complex. Although new trial data have appeared every year, the results are still inconclusive. In this review, we provide readers with information on new strategies for LAHNSCC induction therapy, which will facilitate evidence-based decision making in LAHNSCC treatment.

Plasma oncology: Adjuvant therapy for head and neck cancer using cold atmospheric plasma

The worldwide incidence of head and neck cancer (HNC) exceeds half a million cases annually, and up to half of the patients with HNC present with advanced disease. Surgical resection remains the mainstay of treatment for many HNCs, although radiation therapy, chemotherapy, targeted therapy, and immunotherapy might contribute to individual patient’s treatment plan. Irrespective of which modality is chosen, disease prognosis remains suboptimal, especially for higher staging tumors. Cold atmospheric plasma (CAP) has recently demonstrated a substantial anti-tumor effect. After a thorough literature search, we provide a comprehensive review depicting the oncological potential of CAP in HNC treatment. We discovered that CAP applies to almost all categories of HNC, including upper aerodigestive tract cancers, head and neck glandular cancers and skin cancers. In addition, CAP is truly versatile, as it can be applied not only directly for superficial or luminal tumors but also indirectly for deep solid organ tumors. Most importantly, CAP can work collaboratively with existing clinical oncotherapies with synergistic effect. After our attempts to elaborate the conceivable molecular mechanism of CAP’s anti-neoplastic effect for HNC, we provide a brief synopsis of recent clinical and preclinical trials emphasizing CAP’s applicability in head and neck oncology. In conclusion, we have enunciated our vision of plasma oncology using CAP for near future HNC treatment.

Adjuvant treatment for high-risk salivary gland malignancies and prognostic stratification based on a 20-year single institution experience

BACKGROUND AND AIM

Retrospective analysis of the utility of adjuvant radiation (RT) or chemoradiation (CRT) and identify prognostic features for patients with high-risk head and neck salivary gland cancers.

METHODS

From 1/1997 to 12/2017, 108 patients underwent surgery, and RT (n = 50) or CRT (n = 58) for positive lymph node(s), extracapsular extension, perineural invasion, lymphovascular space invasion, positive/close margin, and/or grade 3 disease. Outcomes were estimated with the Kaplan-Meier method. Significant predictors identified through regression analyses were incorporated into multivariable regression (MVA). Toxicities were compared using chi-square.

RESULTS

The median follow-up was 52 months (range: 3-226). The number of risk factors (RFs) between RT and CRT groups were: 0 to 1 (44% vs 7%), 2 to 3 (48% vs 41%), or 4 to 6 (8% vs 52%), respectively (P < .01). On MVA, stage 3 or 4 disease predicted worse outcomes including overall survival (HR 4.55, P = .01). Increasing number of RFs predicted worse disease-free survival, distant metastasis-free survival, and overall survival (2-3 RFs: HR 3.38, P = .03; 4-6 RFs: HR 5.78, P < .01), but not locoregional control (P = .54). So, adjuvant CRT may have provided comparable locoregional control for patients with more adverse features, but the CRT did not translate into improved distant control. There was no difference in acute or late grade 3+ toxicities, or parenteral nutrition (P = .98, P = .85, and P = .83), respectively.

CONCLUSIONS

Adjuvant CRT provides adequate locoregional control in patients with more adverse RFs. The absolute number of RFs serves prognostic significance and should be considered in future prospective trials.

Head and neck cancer management and cancer stem cells implication

Head and neck squamous cell carcinomas (HNSCCs) arise in the mucosal linings of the upper aerodigestive tract and are heterogeneous in nature. Risk factors for HNSCCs are smoking, excessive alcohol consumption, and the human papilloma virus. Conventional treatments are surgery, radiotherapy, chemotherapy, or a combined modality; however, no international standard mode of therapy exists. In contrast to the conventional model of clonal evolution in tumor development, there is a newly proposed theory based on the activity of cancer stem cells (CSCs) as the model for carcinogenesis. This “CSC hypothesis” may explain the high mortality rate, low response to treatments, and tendency to develop multiple tumors for HNSCC patients. We review current knowledge on HNSCC etiology and treatment, with a focus on CSCs, including their origins, identifications, and effects on therapeutic options.

The role of interim FDG PET-CT after induction chemotherapy as a predictor of concurrent chemoradiotherapy efficacy and prognosis for head and neck cancer

Purpose

Induction chemotherapy (ICT) with docetaxel, cisplatin, and 5-fluorouracil (TPF) followed by concurrent chemoradiotherapy (CCRT) has the advantages of organ preservation and systemic control in head and neck cancer (HNC). Early prediction of CCRT efficacy may help identify patients who will benefit more from surgery than from CCRT. We investigated the role of interim 18-fluoro-2-deoxy-glucose positron emission tomography computed tomography (FDG PET-CT) after ICT to predict the efficacy of CCRT and clinical outcomes.

Methods

Tumor responses were retrospectively reviewed after CCRT based on the Response Evaluation Criteria in Solid Tumors. FDG PET-CT imaging was performed before and after three cycles of TPF. We examined the associations between the metabolic response (percentage decrease in the maximum standardized uptake value [SUVmax] and total metabolic tumor volume [MTV]) after ICT and complete response (CR) to CCRT, progression-free survival (PFS), and overall survival (OS).

Results

We studied 43 HNC patients with a median follow-up of 32.7 months. Lymph node (LN) SUVmax and total MTV decreases from baseline after ICT were greater in patients with a CR to CCRT than in non-CR patients (LN SUVmax, 88.8% vs. 62.5%, respectively; total MTV, 99.7% vs. 89.9%, respectively). Decreases in total MTV ≥ 78% and LN SUVmax ≥73% after ICT predicted CR to CCRT and longer OS and PFS.

Conclusions

Using interim FDG PET-CT to measure SUVmax and total MTV after three cycles of ICT may be a useful technique for identifying HNC patients who will benefit from CCRT and predicting survival outcomes.

Electronic supplementary material

The online version of this article (10.1007/s00259-017-3836-8) contains supplementary material, which is available to authorized users.

Systemic therapy for head and neck squamous cell carcinoma: Historical perspectives and recent breakthroughs

OBJECTIVES

Despite dramatic developments in drugs established for other malignancies, historically there have been few novel systemic agents available for the management of head and neck squamous cell carcinoma (HNSCC). However, the last decade has observed increased interest in targeted therapies for HNSCC. In 2006, cetuximab became the first major drug for HNSCC to gain Food and Drug Administration (FDA) approval in 3 decades. Recently, both pembrolizumab and nivolumab gained FDA approval for treatment of recurrent or metastatic HNSCC, and trials for other indications in HNSCC are actively underway. As older agents including cisplatin and 5-fluorouracil continue to play a significant role in the management of advanced HNSCC, an understanding of their legacy is paramount. This historical review is not meant to exhaustively catalog every finding relating to HNSCC systemic therapy, but rather is meant to highlight important advances.

DATA SOURCES

Case series and clinical trials available in the literature.

REVIEW METHODS

Historically significant series and trials evaluating HNSCC systemic therapy were evaluated.

RESULTS

Standard regimens employed today are largely comprised of drugs discovered over 4 decades ago, although a number of recent phase III clinical trials have shown great promise, leading to the adoption of several new chemotherapeutic agents and treatment strategies.

CONCLUSIONS

These findings reinforce the importance of supporting further HNSCC drug discovery as modern treatment strategies using systemic therapy have resulted in measurable improvements in oncologic outcomes. Laryngoscope, 127:2565-2569, 2017.

Cardiovascular sequel of neck irradiation in head and neck cancer patients

PURPOSE

The baroreflex is an important afferent mechanism controlling autonomic functions. As afferent nerves course through the neck, they are susceptible to damage by neck irradiation in head and neck cancer patients. With increased survival of head and neck cancer patients because of improved therapy, the cardiovascular morbidity and mortality in them have become apparent and this is of clinical concern. There are few case reports of baroreflex failure as a chronic sequel to neck irradiation.

OBJECTIVES

The present study evaluated the changes in cardio-autonomic tone and postural cardiovascular reflex in neck-irradiated patients.

METHODS

Head and neck cancer patients who had received neck irradiation (n = 15) and healthy controls (n = 15) were evaluated for heart rate variability with time domain analysis of 5 min ECG recording. Postural cardiovascular reflexes were studied with changes in blood pressure and heart rate in the lying to standing test.

RESULTS

Our results suggest that there is a reduction in overall time domain measures of heart rate variability and weakened postural reflexes in neck-irradiated patients.

CONCLUSION

Decreased heart rate variability in neck-irradiated patients reflects an independent risk of cardiovascular morbidity. The early detection of cardiovascular impairment in such patients may help healthcare professionals in providing better care. Furthermore, the dose delivered to the carotid sinus should be monitored and restricted.

Taxanes in cancer of the head and neck

Accumulating evidence from clinical trials has shown that taxanes are among the most active antitumor agents currently available for squamous cell carcinoma of the head and neck. They are strong enhancers of the efficacy of radiotherapy in locally advanced cancer and are highly potent chemotherapeutic agents in recurrent/metastatic settings. Paclitaxel and docetaxel, prototypes of taxanes, are already well known and used in the treatment of squamous cell carcinoma of the head and neck, but a newer generation of taxanes is emerging and may possess stronger antitumor activity and/or decreased normal tissue toxicity. Acquired resistance to taxanes has become one of the major therapeutic obstacles, which hopefully will be overcome with a newer generation of taxanes, as our knowledge of the mechanism of resistance has improved.

Multidisciplinary care of the patient with head and neck cancer

Head and neck cancer is a heterogeneous group of cancers, which require a multidisciplinary approach to achieve excellent treatment results. This article focuses on current treatment guidelines and controversies in the management of head and neck cancer. It also provides insight into future directions and newest advances in the treatment of head and neck cancer.

Survival outcomes of patients treated with hypofractionated stereotactic body radiation therapy for parotid gland tumors: a retrospective analysis

Background: to review a single-institution experience with the management of parotid malignancies treated by fractionated stereotactic body radiosurgery (SBRT). Findings: Between 2003 and 2011, 13 patients diagnosed with parotid malignancies were treated with adjuvant or definitive SBRT to a median dose of 33 Gy (range 25–40 Gy). There were 11 male and two female patients with a median age of 80. Ten patients declined conventional radiation treatment and three patients had received prior unrelated radiation therapy to neighboring structures with unavailable radiation records. Six patients were treated with definitive intent while seven patients were treated adjuvantly for adverse surgical or pathologic features. Five patients had clinical or pathologic evidence of lymph node disease. Conclusion: at a median follow-up of 14 months only one patient failed locally, and four failed distantly. The actuarial 2-year overall survival, progression-free survival, and local-regional control rates were 46, 84, and 47%, respectively. Statistical analysis revealed surgery as a positive predictor of overall survival while presence of gross disease was a negatively correlated factor (p < 0.05).

Hydroxyurea: a key player in cancer chemotherapy

Hydroxyurea (HU) is a simple organic compound currently used as a cancer chemotherapeutic agent. It acts specifically on the S-phase of the cell cycle by inhibiting the enzyme ribonucleoside diphosphate reductase, thereby hindering the reductive conversion of ribonucleotides to deoxyribonucleotides and thus limiting de novo DNA synthesis. HU is employed in hemotological settings as a first-line treatment of myeloproliferative disorders, such as polycythemia vera, essential thrombocythemia and primary myelofibrosis, apart from having a vital role in combination therapy for management of malignant melanoma, head and neck cancers and brain tumors. It offers an advantage that the patient may take this drug on an ambulatory basis with minimum clinical toxicity, while some of its limitations include gastrointestinal disturbance and bone marrow depression. This review will summarize and present the overall effects of HU and its combination therapy as an anticancer agent.

Distant metastases from head and neck squamous cell carcinoma. Part III. Treatment

Distant metastases from head and neck squamous cell carcinoma (HNSCC), though rare at initial presentation, remain an important manifestation of cancer recurrence and mortality. Although generally considered incurable with a dismal prognosis despite palliative therapy, highly selected patients with distant metastases may have a long term survival benefit from aggressive surgery or radiotherapy. Advances in systemic treatments also may improve patient survival. This article reviews the current state of management of HNSCC patients with distant metastases.

Reirradiation of recurrent salivary gland malignancies with fractionated stereotactic body radiation therapy

PURPOSE: The purpose of this study was to review a single-institution experience with the reirradiation of recurrent salivary gland tumors using fractionated stereotactic radiosurgery (SBRT). METHODS: Between 2003 and 2011, 18 patients diagnosed with recurrent, previously irradiated, salivary gland carcinomas were treated with SBRT reirradiation. Median age was 68 for all patients with most tumors being of major salivary gland origin. Most patients did not undergo surgical resection, and among those that did, all had positive margins. Only seven patients received chemotherapy, and the median SBRT dose was 30 Gy given in five fractions with a median cumulative dose of 91.1 Gy. RESULTS: The median overall survival (OS), progression-free survival (PFS), and local control (LRC) were 11.5, 3.5, and 5.5 months, respectively. The 2-year OS, PFS, and LRC rates were 39%, 24%, and 53%, respectively. Statistical analysis identified presence of gross disease and interval to reirradiation as negative predictors of survival outcomes on both univariate and multivariate analyses (p < 0.05). On multivariate analysis, tumor volume was a negative predictor of survival outcomes (p < 0.05). Long-term toxicity analysis revealed four patients in the reirradiated group with soft tissue necrosis, which correlated with the cumulative dose (p = 0.01). CONCLUSION: Our data suggest that SBRT is a reasonable treatment option for reirradiation of salivary gland tumors, but further studies are warranted.

Ribonucleotide reductase inhibitors: a new look at an old target for radiosensitization

Ribonucleotide reductase (RR), the rate limiting enzyme in the synthesis and repair of DNA, has been studied as a target for inhibition in the treatment of cancer for many years. While some researchers have focused on RR inhibitors as chemotherapeutic agents, particularly in hematologic malignancies, some of the most promising data has been generated in the field of radiosensitization. Early pre-clinical studies demonstrated that the addition of the first of these drugs, hydroxyurea, to ionizing radiation (IR) produced a synergistic effect in vitro, leading to a large number of clinical studies in the 1970–1980s. These studies, mainly in cervical cancer, initially produced a great deal of interest, leading to the incorporation of hydroxyurea in the treatment protocols of many institutions. However, over time, the conclusions from these studies have been called into question and hydroxyurea has been replaced in the standard of care of cervical cancer. Over the last 10 years, a number of well-done pre-clinical studies have greatly advanced our understanding of RR as a target. Those advances include the elucidation of the role of p53R2 and our understanding of the temporal relationship between the delivery of IR and the response of RR. At the same time, new inhibitors with increased potency and improved binding characteristics have been discovered, and pre-clinical and early clinical data look promising. Here we present a comprehensive review of the pre-clinical and clinical data in the field to date and provide some discussion of future areas of research.

Integrating systemic agents into multimodality treatment of locally advanced head and neck cancer

Although highly debated in the 1980s, randomized clinical trials have provided undeniable evidence that systemic chemotherapy, as part of a multimodality treatment collaboration, is effective in improving survival, organ preservation and local-regional control in locally advanced head and neck cancer (HNC). We are entering an exciting period in which new chemotherapy agents, new paradigms of treatment, new surgical and radiation technology, and new prognostic factors are rapidly becoming available. Information on how to integrate these new tools and on how they affect long-term outcomes are lacking, making decision making and treatment planning more difficult. With unprecedented survival and the changing demographics of HNC we must now consider long-term consequences in addition to survival and local and regional control as important factors in therapeutic decision making. The availability of different treatment plans that incorporate systemic chemotherapy, radiotherapy and surgery give us many tools with which to craft a treatment for each individual patient. Today, in this exciting and chaotic period, a multidisciplinary and collaborative approach for each HNC patient at the start of decision making and planning is a necessity and the absolute standard of medical treatment for excellent patient care.

Adjuvant chemoradiotherapy for locoregionally advanced and high-risk salivary gland malignancies

Background

To report the outcomes of patients with locoregionally advanced and high- risk salivary gland malignancies treated with surgery followed by adjuvant chemoradiotherapy.

Methods

From 09/1991 - 06/2007, 24 high-risk salivary gland cancer patients were treated with surgery, followed by adjuvant chemoradiotherapy for high-risk pathologic features including, perineural involvement, nodal involvement, positive margins, or T3/T4 tumors. Chemoradiotherapy was delivered for 4-6 alternating week cycles: the most common regimen, TFHX, consisted of 5 days paclitaxel (100 mg/m² on d1), infusional 5-fluorouracil (600 mg/m²/d × 5d), hydroxyurea (500 mg PO BID), and 1.5 Gy twice daily irradiation followed by a 9-day break without treatment.

Results

Median follow-up was 42 months. The parotid gland was more frequently involved (n = 17) than minor (n = 4) or submandibular (n = 3) glands. The median radiation dose was 65 Gy (range 55-68 Gy). Acute treatment related toxicity included 46% grade 3 mucositis and 33% grade 3 hematologic toxicity. Six patients required feeding tubes during treatment. One patient progressed locally, 8 patients progressed distantly, and none progressed regionally. Five-year locoregional progression free survival was 96%. The 3 and 5 year overall survival was 79% and 59%, respectively. Long-term complications included persistent xerostomia (n = 5), esophageal stricture requiring dilatation (n = 1), and tempromandibular joint syndrome (n = 1).

Conclusions

Surgical resection followed by adjuvant chemoradiotherapy results in promising locoregional control for high-risk salivary malignancy patients.

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

BACKGROUND

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

METHODS

Between 1990 and 2004, 127 patients with stage III or IV base of tongue cancer were treated with chemoradiotherapy on protocol. Indications included nodal involvement, T3/T4 tumors, positive margins, those patients refusing surgery, or were medically inoperable. The most common regimen was paclitaxel (100 mg/m2 on day 1), infusional 5-fluorouracil (600 mg/m2/day × 5 days), hydroxyurea (500 mg prescribed orally [PO] 2 × daily [BID]), and 1.5 Gy twice daily irradiation followed by a 9-day break without treatment.

RESULTS

Median follow-up was 51 months. The median dose to gross tumor was 72.5 Gy (range, 40-75.5 Gy). Five-year locoregional progression-free survival, overall survival, and disease-free survival was 87.0%, 58.2%, and 46.0%, respectively.

CONCLUSION

Concurrent chemoradiotherapy results in promising locoregional control for base of tongue cancer. As distant relapse was common, further investigation of systemic therapy with novel agents may be warranted.

Sequential chemoradiotherapy in advanced laryngeal cancer: an institutional experience

AIM

The objective of this study was to determine the efficacy of sequential chemoradiation for larynx preservation.

METHODS

Between October 2002 and December 2007, 76 patients with T3, T4 and N+ laryngeal cancer who had refused a laryngectomy or had unresectable disease (medically or surgically) enrolled in this study. The chemotherapy consisted of three cycles of docetaxel (75 mg/m(2) on day 1), cisplatin (75 mg/m(2) on day 1) and 5-flurouracil (5-FU) (750 mg/m(2) by infusion on days 1-3). All patients were assigned to receive radiotherapy (70 Gy to primary site). The Kaplan-Meier method was used to obtain survival outcomes.

RESULTS

The median follow up was 36 months. A chemotherapy clinical response (complete and partial) was observed in 51 patients (67.1%). The 2-year laryngeal preservation rate was 75%. Actuarial progression-free survival rates of 71% and 67% were observed at 2 and 3 years, respectively. Actuarial overall survival rates were 83% and 71% at 2 and 3 years, respectively. Disease progression was seen in 26 patients (34.2%). Grade 3 and 4 neutropenia occurred in 39 (51.3%) patients.

CONCLUSION

Sequential chemotherapy with docetaxel, cisplatin and 5-flurouracil followed by radiation may be an alternative to a laryngectomy in patients with advanced laryngeal cancer.

Relationships observed in the structure and spectra of uracil and its 5-substituted derivatives

The effects on the geometry structure, atomic charges and vibrational wavenumbers of the main different substituents in the 5th position of the uracil ring were analysed, and relationships were established. The 5-monosubstituted derivatives studied were 5-XU (X=F, Cl, Br, I, CH(3), NH(2), NO(2)). The geometry and vibrational wavenumbers were determined in these molecules. The FT-IR and Raman spectra were studied with the support of B3LYP calculations using several basis sets. Several general conclusions were underlined.

Diffusion-weighted imaging in head and neck cancers

This article reviews the utility of diffusion-weighted imaging (DWI) in the diagnosis, prognosis and monitoring of treatment response in tumors arising in the head and neck region. The apparent diffusion coefficient (ADC) value, determined from DWI, can help in cancer staging and detection of subcentimeter nodal metastasis. The ADC value also discriminates carcinomas from lymphomas, benign lesions from malignant tumors and tumor necrosis from abscesses. Low pretreatment ADC values typically predict a favorable response to chemoradiation therapy. These promising reports indicate the potential of DWI as a potential biomarker for diagnosis and monitoring of treatment response in head and neck cancers. In view of the overlapping ADC values between different salivary gland tumors, care should be taken when interpreting these results and other imaging parameters should be considered for a better diagnosis. Susceptibility and motion-induced artifacts may sometimes degrade DWI image quality; however, novel techniques are being developed to overcome these drawbacks.

Validation of lysyl oxidase as a prognostic marker for metastasis and survival in head and neck squamous cell carcinoma: Radiation Therapy Oncology Group trial 90-03

PURPOSE

To validate lysyl oxidase (LOX), a hypoxia-related protein, as a marker for metastasis in an independent head and neck cancer (HNC) patient group enrolled onto a prospective trial.

PATIENTS AND METHODS

We performed traditional immunohistochemical (IHC) staining and automated quantitative analysis (AQUA) for LOX expression in 66 HNC patients from one institution. We also performed AQUA staining for LOX in 306 of 1,113 patients treated on a phase III trial comparing four radiation fractionation schedules in locally advanced HNC (RTOG 90-03). Pretreatment characteristics and outcome were similar between patients with and without LOX assessment. We correlated AQUA LOX expression with time to metastasis (TTM), time to progression (TTP), and overall survival (OS).

RESULTS

LOX expression from both staining methods predicted for TTM in the first 66 patients. Multivariate analysis, controlling for significant parameters including nodal stage and performance status, revealed tumor LOX expression, as a continuous variable, was an independent predictor for TTM (hazard ratio [HR], 1.21; 95% CI, 1.10 to 1.33; P = .0001), TTP (HR, 1.06; 95% CI, 1.02 to 1.10; P = .0069), and OS (HR, 1.04; 95% CI, 1.00 to 1.07; P = .0311) in RTOG 90-03 patients. This translates into a 259% increase in metastatic risk for a patient at the 75th percentile of LOX compared with one at the 25th percentile.

CONCLUSION

AQUA LOX expression was strongly associated with increased metastasis, progression, and death in RTOG 90-03 patients. This study validates that LOX is a marker for metastasis and survival in HNC.

Antimetabolite radiosensitizers

Radiosensitization with antimetabolites has improved clinical outcome for patients with solid malignancies, especially cancers of the GI tract, cervix, and head and neck. Fluorouracil (FU) and hydroxyurea have been widely used clinically during the last four decades, and promising results have been observed more recently with gemcitabine. Although the antimetabolites all target DNA replication, they differ with respect to the mechanisms by which they produce radiosensitization. The antimetabolite radiosensitizers may inhibit thymidylate synthase (TS) or ribonucleotide reductase, and the nucleoside/nucleobase analogs can be incorporated into DNA. Radiosensitization can result from chemotherapy-induced increase in DNA double-strand breaks or inhibition of their repair. Studies of repair pathways involved in radiosensitization with antimetabolites implicate base excision repair with the TS inhibitors, homologous recombination with gemcitabine, and mismatch repair with FU and gemcitabine. Gemcitabine can also stimulate epidermal growth factor receptor (EGFR) phosphorylation; inhibiting this effect with EGFR inhibitors can potentiate cytotoxicity and radiosensitization. Additional work is necessary to determine more precisely the processes by which antimetabolites act as radiation sensitizers and to define the optimal sequencing of these agents with EGFR inhibitors to provide better guidance for clinical protocols combining these drugs with radiotherapy.

Ar-matrix IR spectra of 5-halouracils interpreted by means of DFT calculations

The infrared low-temperature Ar-matrix spectra of 5-halouracils and unsubstituted uracil were measured and interpreted in terms of the spectra calculated at the DFT/B3PW91/6-311G level followed by a potential energy distribution (PED) analysis. For the PED analysis, the sets of halouracil mode definitions were constructed so that dissimilarities in the interpretations of the different spectra were minimized. Anharmonic frequency calculations enabled more light to be shed on the Fermi resonance (FR) phenomena occurring in the nu(C=O) stretching vibrations region. For each halouracil vibrational spectrum, several FRs manifest themselves in the nu(C=O) stretching vibrations region. We show that the most frequent components participating in these resonances are the nu(C(4)=O(10)) frequency, a beta(N-H) mode frequency, and a beta(C=O) mode frequency. The experimental nu(N-H) frequencies are reproduced by the calculated anharmonic frequencies better than by the scaled harmonic ones, and the nu(C=O) frequencies respond in the opposite manner. The experimental frequencies located below 1500 cm(-1) are reproduced equally well by the two kinds of calculations.

Induction chemotherapy in the management of squamous cell carcinoma of the head and neck

Platinum-based chemotherapy administered concurrently with radiation has been adopted as the standard treatment for locally advanced head and neck squamous cell carcinoma. Historically, randomized trials using induction chemotherapy prior to radiation therapy alone have failed to demonstrate a clear survival advantage, and concurrent chemoradiation has delivered better results than previously obtained with radiation therapy alone, establishing the benefit of adding chemotherapy. This method of treatment, together with new modalities of therapy and novel agents, has reintroduced the question of induction chemotherapy before definitive chemoradiation. Systemic chemotherapy offers a better possibility of reducing systemic metastasis and improving cosmetic appearance. This article reviews developing trends using induction chemotherapy followed by chemoradiation in patients with head and neck squamous cell carcinoma.

New and emerging radiosensitizers and radioprotectors

The combination of chemotherapy and radiation has led to clinical breakthroughs in several disease sites, and current work continues to define optimum combinations of proven chemotherapy as well as more recently available, noncytotoxic agents. Administration of systemic therapies allows modulation of radiation response to improve tumor control (radiosensitization) or to prevent normal tissue toxicity (radioprotection). Substantial progress has been made in identifying the targets of standard chemotherapeutic radiation sensitizers and protectors as well as in the introduction of a new generation of molecularly targeted therapies in combination with radiation. We have reviewed the most recent, predominantly early phase clinical trials combining systemic agents with radiation. Although the proof of an improved schedule ultimately needs to come from well-run Phase III trials, the search among schedules could be shortened by the use of surrogate endpoints such as presence of active drug metabolites in the tumor. This has been accomplished only in a few cases and needs to become a more standard part of radiation sensitizer and protector trials.

High survival and organ function rates after primary chemoradiotherapy for intermediate-stage squamous cell carcinoma of the head and neck treated in a multicenter phase II trial

PURPOSE

Patients with intermediate-stage squamous cell carcinoma of the head and neck traditionally have been treated with initial surgical resection followed by radiotherapy (RT) alone or chemoradiotherapy. A previous study in this patient population reported a 91% locoregional control rate and 65% overall survival (OS) rate at 5 years, with chemoradiotherapy used as primary treatment. This study was undertaken to assess whether shortening treatment duration with hyperfractionated RT would be feasible and improve locoregional control, organ preservation, and progression-free survival.

METHODS

Eligible patients with stage II or III disease received fluorouracil, hydroxyurea, and RT given twice daily on a week-on/week-off schedule. Quality-of-life scores were measured using three validated indexes.

RESULTS

All 53 patients enrolled are included in the analysis, with a median follow-up of 42 months (range, 5 to 98 months). Grade 3 or 4 in-field mucositis was observed in 77% and 9%, respectively. No patients required surgical salvage at the primary tumor site (pathological complete response rate, 100%). The 3-year progression-free and OS rates are 67% and 78%, respectively. The 3-year disease-specific mortality rate is 7%. At the time of analysis, 87% of surviving patients do not require enteral feeding support. Quality-of-life and performance assessment indicated that, although acute treatment toxicities were severe, most patients returned to pretreatment function by 12 months.

CONCLUSION

Concurrent chemoradiotherapy with hyperfractionated RT is feasible in this patient population and yields high local control and cure rates. Compared with our historical control using once-daily fractionation, hyperfractionation is accompanied by increased acute in-field toxicity.

Advances in the treatment of locally advanced non-nasopharyngeal squamous cell carcinoma of the head and neck region

Over the past decade important advances have been made in the treatment of locally advanced squamous cell carcinoma of the head and neck (SCCHN). Traditionally, chemotherapy has been incorporated in the treatment of SCCHN either before local treatment as induction, concomitantly with radiation, or following local treatment as adjuvant therapy. A number of randomized trials and meta-analyses have demonstrated that induction chemotherapy (usually based on the combination of cisplatin and 5-d continuous infusion of fluorouracil) followed by local treatment or concomitant chemoradiotherapy (CCRT) each prolongs survival and results in organ preservation in a significant number of patients. Survival rates appear to be higher when CCRT with cisplatin is used. Furthermore, accelerated fractionation radiation regimens have shown improved local control rates in randomized trials. Recently, new therapeutic strategies such as induction chemotherapy followed by CCRT or the incorporation of newer agents such as taxanes are under intense investigation and preliminary results are promising. Advances in molecular biology have led to the elucidation of molecular mechanisms that initiate and maintain the malignant phenotype in SCCHN. The identification of molecular targets has revolutionized our approach to cancer therapy and resulted in the introduction of novel targeted therapies. Cyclin-dependent kinases, the tumor suppressor p53 gene, and epidermal growth factor receptor are some of the molecular targets of such therapies in patients with SCCHN.

Benefit of postoperative chemoradiotherapy for patients with unknown primary squamous cell carcinoma of the head and neck

BACKGROUND

Postopertative adjuvant chemoradiotherapy recently became an established modality for patients with selected high-risk locally advanced head and neck cancers. The optimal treatment of unknown primary squamous cell cancer of the head and neck (SCCHN) continues to be controversial, since major randomized studies excluded those patients.

METHODS

We conducted a retrospective review of patients treated during 1995 to 2002 for unknown primary SCCHN. All patients were treated with a neck dissection followed by concurrent high-dose cisplatin (100 mg/m(2)) and bilateral neck radiotherapy.

RESULTS

Thirty-seven patients were identified with nodal disease distribution of N1 (5%), N2a (22%), N2b (41%), N2c (8%), N3 (22%), and Nx (3%). Modified neck dissection was done on the majority (30/37 = 81%) of patients. With a median follow-up of 42 months among the survivors, very few patients had regional recurrence (5%) or distant failure (11%), and 89% of patients were alive. The actuarial 5-year overall survival rate could not be estimated because there were no deaths beyond 20 months after surgery. Substantial yet acceptable acute and late morbidities were demonstrated in this cohort of patients.

CONCLUSIONS

Postoperative chemoradiotherapy is of potential benefit to patients with unknown primary SCCHN by improving survival and reducing failures. This treatment warrants further prospective evaluation.

Phase II clinical trial of parenteral hydroxyurea and hyperfractionated, accelerated external beam radiation therapy in patients with advanced squamous cell carcinoma of the head and neck: Toxicity and efficacy with continuous ribonucleoside reductase inhibition

BACKGROUND

Almost all concurrent chemoradiation regimens for head and neck are platinum based; however, cisplatin is associated with severe renal, oto-, and neurotoxicity. Hydroxyurea (HU) has been associated with fewer irreversible toxicities. We obtained HU in parenteral form to be administered continually during the radiation treatment. Intravenous HU promised better pharmacokinetics and cell cycle blockade.

METHODS

Participants had biopsy-proven, untreated squamous cell carcinoma of the oral cavity, oropharynx (stage IV) and hypopharynx (stages II-IV). Radiation therapy consisted initially of 74.4 Gy administered in twice daily 1.2-Gy fractions. After 20 patients, the radiation dose was reduced to 60.0 Gy, and another 16 patients were enrolled.

RESULTS

Patients received HU by Continuous Ambulatory Drug Delivery (CADD) pump on a daily x5 schedule during radiation therapy. Because of persistent long-term dysphagia, after 20 patients, the dose of external beam radiation therapy was reduced from 74 to 60 Gy, and the duration of concurrent HU was correspondingly reduced. The new regimen was much better tolerated. The median survival for the group as a whole was 30 months. Within this small study, there were no significant differences in survival, regional control, or local control between the 2 groups.

CONCLUSIONS

Lower doses of concurrent parenteral HU and hyper-fractionated radiation therapy are tolerable and promising.

Neck dissection in the combined-modality therapy of patients with locoregionally advanced head and neck cancer

PURPOSE

The purpose of this study was to evaluate the role of neck lymph node (ND) in the combined dissection modality therapy for locoregionally advanced head and neck.

METHODS

We identified patients with N2-N3 head and neck cancers who were enrolled in three consecutive multicenter phase II studies of concurrent chemoradiotherapy utilizing 5-fluorouracil and hydroxyurea on an alternate-week schedule with radiotherapy twice daily plus either cisplatin (C-FHX) or paclitaxel (T-FHX). Patients with unknown primary tumors, nasopharyngeal or paranasal sinus primaries, nonsquamous histology, progression or death during therapy, or incomplete therapy were excluded.

RESULTS

A total of 131 patients were analyzed. Seventy-nine percent had N2 stage. ND was performed in 92 patients (70%), either prior to enrollment (n = 31) or after chemoradiotherapy (n = 61). With a median follow-up of 4.6 years, the 5-year locoregional and neck progression-free survival (PFS) rates were higher in patients with ND versus patients without ND: 88% versus 74% (p =.02) and 99% versus 82% (p =.0007). respectively; there was also a trend toward improved overall survival (OS) with ND, but PFS and distant PFS were comparable. In the subset of patients with N3 disease, ND was associated not only with better locoregional control but also with improved distant PFS. However, in patients with clinical complete response (n = 92), no significant differences in PFS (68% vs 75% at 5 years, p =.53) or any other survival parameters with or without ND were observed.

CONCLUSIONS

ND improves neck control and is required for patients with clinically residual disease or N3 neck cancer but has no significant impact on the outcome of patients with N2 stage disease who are rendered clinically disease-free with intensive concurrent chemoradiotherapy.