Supraglottic laryngeal carcinoma: an analysis of dose-time-volume factors in 410 patients

Cetuximab and Radiotherapy in Laryngeal Preservation for Cancers of the Larynx and Hypopharynx: A Secondary Analysis of a Randomized Clinical Trial

IMPORTANCE

The appropriate use of surgery or radiotherapy-based approaches for organ preservation has been the subject of much debate. Unfortunately, there has been a lack of improvement in overall survival for patients with laryngeal carcinoma in the last 30 years.

OBJECTIVE

To assess the rates of laryngeal preservation and laryngectomy-free survival in patients receiving cetuximab and radiotherapy (CRT) and patients receiving radiotherapy alone.

DESIGN, SETTING, AND PARTICIPANTS

Patients were enrolled in a multicenter, open-label, stratified, randomized, phase 3 study from April 1, 1999, through March 31, 2002, from 73 centers in the United States and 14 other countries. A secondary subgroup analysis of patients with hypopharyngeal and laryngeal carcinoma was undertaken. Rates of laryngeal preservation and laryngectomy-free survival were estimated by the Kaplan-Meier method. The hazard ratios (HRs) were calculated using a Cox proportional hazards regression model. Quality of life was evaluated using the European Organization for Research and Treatment of Cancer core questionnaire and head and neck module.

MAIN OUTCOMES AND MEASURES

Laryngeal preservation and laryngectomy-free survival.

RESULTS

Of the 424 patients included in the trial, 168 treated patients with cancer of the larynx or hypopharynx were included in this analysis (90 in the CRT group and 78 in the radiotherapy alone group). The median (range) age of the patients was 59 (40-80) years in the CRT group and 61 (35-81) years in the radiotherapy alone group. In the CRT group, 72 patients (80.0%) were male and 18 (20.0%) were female. In the radiotherapy alone group, 62 (79.5%) were male and 16 (20.5%) were female. The rates of laryngeal preservation at 2 years were 87.9% for CRT vs 85.7% for radiotherapy alone, with an HR of 0.57 (95% CI, 0.23-1.42; P = .22). Similarly, the HR for laryngectomy-free survival comparing CRT vs radiotherapy alone was 0.78 (95% CI, 0.54-1.11; P = .17). This study was not powered to assess organ preservation. Median overall survival was 27 (95% CI, 20-45) vs 21 (95% CI, 17-35) months for the CRT and radiotherapy alone groups, respectively, with an HR of 0.87 (95% CI, 0.60-1.27). No differences between treatments were reported regarding overall quality of life, need for a feeding tube, or speech.

CONCLUSIONS AND RELEVANCE

The results of a possible cetuximab-related laryngeal preservation benefit for patients with hypopharyngeal or laryngeal cancer are intriguing; these results need to be interpreted in the context of a retrospective subset analysis with limited sample size.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00004227.

Patterns of Recurrence in Electively Irradiated Lymph Node Regions After Definitive Accelerated Intensity Modulated Radiation Therapy for Head and Neck Squamous Cell Carcinoma

PURPOSE

To provide a comprehensive risk assessment on the patterns of recurrence in electively irradiated lymph node regions after definitive radiation therapy for head and neck cancer.

METHODS AND MATERIALS

Two hundred sixty-four patients with stage cT2-4N0-2M0 squamous cell carcinoma of the oropharynx, larynx, or hypopharynx treated with accelerated intensity modulated radiation therapy between 2008 and 2012 were included. On the radiation therapy planning computed tomography (CT) scans from all patients, 1166 lymph nodes (short-axis diameter ≥5 mm) localized in the elective volume were identified and delineated. The exact sites of regional recurrences were reconstructed and projected on the initial radiation therapy planning CT scan by performing coregistration with diagnostic imaging of the recurrence.

RESULTS

The actuarial rate of recurrence in electively irradiated lymph node regions at 2 years was 5.1% (95% confidence interval 2.4%-7.8%). Volumetric analysis showed an increased risk of recurrence with increasing nodal volume. Receiver operating characteristic analysis demonstrated that the summed long- and short-axis diameter is a good alternative for laborious volume calculations, using ≥17 mm as cut-off (hazard ratio 17.8; 95% confidence interval 5.7-55.1; P<.001).

CONCLUSIONS

An important risk factor was identified that can help clinicians in the pretreatment risk assessment of borderline-sized lymph nodes. Not overtly pathologic nodes with a summed diameter ≥17 mm may require a higher than elective radiation therapy dose. For low-risk elective regions (all nodes <17 mm), the safety of dose de-escalation below the traditional 45 to 50 Gy should be investigated.

Organ Preservation for Advanced Larynx Cancer: Issues and Outcomes

PURPOSE

To provide a review of the clinical data, controversies, and limitations that underpin current recommendations for approaches to larynx preservation for locally advanced larynx cancer requiring total laryngectomy.

METHODS

The key findings from pivotal randomized controlled trials are discussed, including quality of life, late effects, and function assessments. Trials investigating taxane inclusion in induction chemotherapy and trials of epidermal growth factor receptor inhibition for radiosensitization are put into perspective for larynx cancer. Controversies in the management of T4 primaries and the opportunities for conservation laryngeal surgery are reviewed.

RESULTS

There are data from clinical trials to support induction chemotherapy, followed by radiotherapy (preferred approach in Europe) and concomitant cisplatin plus radiotherapy (preferred in North America) for nonsurgical preservation of the larynx. Treatment intensification by a sequential approach of induction, followed by concomitant treatment, is investigational. Transoral laryngeal microsurgery and transoral robotic partial laryngectomy have application in selected patients.

CONCLUSION

The management of locally advanced larynx cancer is challenging and requires an experienced multidisciplinary team for initial evaluation, response assessment, and support during and after treatment to achieve optimal function, quality of life, and overall survival. Patient expectations, in addition to tumor extent, pretreatment laryngeal function, and coexisting chronic disease, are critical factors in selecting surgical or nonsurgical primary treatment.

Efficacy of neck treatment in patients with head and neck squamous cell carcinoma

BACKGROUND

Treatment of head and neck squamous cell carcinoma (HNSCC) addresses the primary tumor and the lymphatic drainage. Modalities for the neck are neck dissection and/or radiation therapy. In most cases, the neck is treated by the modality that seems more appropriate for the primary. The aim of this study was to analyze the results of the neck treatments either by neck dissection alone, by radiation therapy alone or by neck dissection followed by radiation therapy.

METHODS

This was a retrospective chart analysis of 699 patients treated for a previously untreated HNSCC. The primary endpoint was recurrence at the treated neck.

RESULTS

Two hundred eighty-one (40%) patients underwent primary neck irradiation, 219 (31%) neck dissection alone, and 199 (29%) neck dissection followed by adjuvant irradiation. The 5-year regional control rates after neck dissection alone were 83% for pN0, 75% for pN1, 60% for pN2a, 59% for pN2b, and 50% for pN2c; after radiation alone, 89% for cN0, 87% for cN1, 40% for cN2a, 60% for cN2b, and 48% for cN2c; and after neck dissection with adjuvant radiation, 86% for pN0, 96% for pN1, 100% for pN2a, 88% for pN2b, and 88% for pN2c.

CONCLUSIONS

Radiation or neck dissection alone are efficient to control early neck disease. For advanced N2/3 neck disease, neck dissection followed by adjuvant radiation is highly efficient, whereas primary radiation results in a high number of regional failures. The literature suggests planned neck dissection to improve regional control for these patients.

Two-field versus three-field irradiation technique in the postoperative treatment of head-and-neck cancer

PURPOSE

We have increasingly used a two-field noncoplanar "caudal tilt" technique (CTT) for irradiating postlaryngectomy and pharyngectomy patients to avoid matchline problems that can be encountered with the classic three-field head-and-neck radiation technique (3FT). This report compares the clinical outcomes of patients treated with postoperative radiation (PORT) using either 3FT or CTT.

METHODS AND MATERIALS

We conducted a retrospective review of the medical records of all patients with laryngeal or hypopharyngeal cancers consecutively treated with PORT between 1997 and 2002. Three-dimensional dosimetric planning was carried out for all patients.

RESULTS

Of 91 patients, 39 were treated with 3FT and 52 with CTT. The median follow-up was 34 months. Estimated rates of 2-year locoregional control, disease-free survival, and overall survival for patients treated with 3FT and CTT were, respectively, 92% and 85% (p=0.241), 62% and 55% (p=0.497), and 77% and 72% (p=0.616). There were no significant differences in the incidence of acute or late side effects in the two groups.

CONCLUSIONS

"Caudal tilt" technique is often used as an alternative to 3FT for postoperative radiotherapy in cases of greater medical and technical complexity. Despite its use in more challenging cases, CTT provides similar long-term clinical outcomes compared with standard 3FT, when computerized three-dimensional dosimetry is used to assure adequate dosimetry throughout the treated volume.

Supraglottic Laryngeal Cancer: Analysis of Treatment Results

OBJECTIVE

This study reports the results of treatment for supraglottic laryngeal cancer with nine different treatment modalities with long-term follow-up.

STUDY DESIGN

Retrospective study of 653 patients with supraglottic laryngeal squamous cell cancer treated from April 1955 to January 1999.

METHODS

The study population included previously untreated patients with cancer of the supraglottic larynx treated with curative intent by one of nine treatment modalities and who were eligible for 5-year follow-up. The treatment modalities included subtotal supraglottic laryngectomy (SSL), SSL with neck dissection (SSL/ND), total laryngectomy (TL), TL/ND, radiation therapy (RT), SSL/RT, SSL/ND/RT, TL/RT, and TL/ND/RT. Multiple diagnostic, treatment, and follow-up parameters were studied using standard statistical analysis to determine significance.

RESULTS

None of the nine treatment modalities produced a survival advantage, either overall or within the stages. Overall disease specific survival (DSS) by treatment modality included SSL 88.9%, SSL/ND 75.8%, TL 83.3%, TL/ND 66.7%, RT 47.2%, SSL/RT 68.9%, SSL/ND/RT 68.1%, TL/RT 59.3%, and TL/ND/RT 46.7%. Improved DSS and cumulative disease specific survival rates were associated with patients under the age of 65 years (P = .0001), early stage disease, N0 disease (P = .0001), clear resection margins (P = .0094), and no recurrence (P = .0001). Posttreatment function showed that 90% of patients were functional in everyday life, 90.7% were eating satisfactorily, 91.4% were breathing naturally, and 83% of SSL patients, 85.7% of RT patients, and 52.8% of TL patients had "good" voices. Laryngeal preservation was accomplished in 86.1% of SSL patients and 72.7% of RT patients (P = .0190).

CONCLUSIONS

No treatment modality produced a survival advantage. Because SSL produced the best rate of laryngeal preservation, we recommend its use in treating the primary in eligible patients. The importance of clear resection margins is stressed. Patients with N+ disease should have the neck treated. Patients with N0 disease may be observed safely with no loss of survival advantage. Because of the pattern of recurrence and the high rates of distant metastasis and second primary cancers, follow-up for a period of not less than 8 years is recommended.

Management of Stage IV Glottic Carcinoma: Therapeutic Outcomes

OBJECTIVES/HYPOTHESIS

The best therapeutic approach for the treatment of stage IV glottic carcinoma is controversial.

STUDY DESIGN

A retrospective study.

METHODS

A retrospective study of Tumor Research Project data was performed using patients with stage IV glottic squamous cell carcinoma treated with curative intent by five different treatment modalities from 1955 to 1998 at Washington University School of Medicine and Barnes-Jewish Hospital (St. Louis, MO).

RESULTS

Ninety-six patients with stage IV glottic carcinoma were treated by five modalities: total laryngectomy (TL) (n = 13), total laryngectomy with neck dissection (TL/ND) (n = 18), radiation therapy alone (RT) (n = 7) (median dose, 69.5 Gy), total laryngectomy combined with radiation therapy (TL/RT) (n = 10), and total laryngectomy and neck dissection combined with radiation therapy (TL/ND/RT) (n = 48). The overall 5-year observed survival (OS) rate was 39%, and the 5-year disease-specific survival (DSS) rate was 45%. The 5-year DSS rates for the individual treatment modalities included the following: TL, 58.3%; TL/ND, 42.9%; RT, 50.0%; TL/RT, 30.0%; and TL/ND/RT, 43.9%. There was no significant difference in DSS for any individual treatment modality (P =.759). The overall locoregional control rate was 69% (66 of 96). The overall recurrence rate was 39% with recurrence at the primary site and in the neck at 19% and 17%, respectively. Recurrence was not related to treatment modality. The 5-year DSS after treatment of locally recurrent cancer (salvage rate) was 30% (3 of 10) and for recurrent neck disease (28 of 67) was 42%. The incidence of delayed regional metastases was 28%; of distant metastasis, 12%; and of second primary cancers, 9%. There was no statistically significant difference in survival between node-negative (N0) necks initially treated (5-y DSS, 31%) versus N0 necks observed and later treated if necessary (5-y DSS, 44%) (P =.685).

CONCLUSION

The five treatment modalities had statistically similar survival, recurrence, and complication rates. The overall 5-year DSS for patients with stage IV glottic carcinoma was 45%, and the OS was 39%. The cumulative disease-specific survival (CDSS) was 0.4770 with a mean survival of 10.1 years and a median survival of 3.9 years. Patients younger than age 55 years had better survival (DSS) than patients 56 years of age or older (P =.0002). Patients with early T stage had better survival than patients with more advanced T stage (P =.04). Tumor recurrence at the primary site (P =.0001) and in the neck (P =.014) and distant metastasis (P =.0001) had a deleterious effect on survival. Tumor recurrence was not related to treatment modality. Patients with clear margins of resection had a statistically significant improved survival (DSS and CDSS) compared with patients with close or involved margins (P =.0001). Post-treatment quality of life was not significantly related to treatment modality. Patients whose N0 neck was treated with observation and appropriate treatment for subsequent neck disease had statistically similar survival compared with patients whose N0 neck was treated prophylactically at the time of treatment of the primary. A minimum of 7 years of follow-up is recommended for early identification of recurrent disease, second primary tumors, and distant metastasis. None of the standard treatment modalities currently employed has a statistical advantage regarding survival, recurrence, complications, or quality of life.

Radical radiation vs surgery plus post-operative radiation in advanced (resectable) supraglottic larynx and pyriform sinus cancers: a prospective randomized study

AIM

Survival in head and neck cancers reflect loco-regional control. With an aim of organ and function preservation the present study was undertaken to compare local failure and survivals.

MATERIAL AND METHODS

Between August 1991-December 1995, 72 patients with resectable advanced supraglottic cancers, were randomized to radical surgery followed by post-operative radiation therapy (Sx+PORT) (Arm I) or radical radiation therapy followed by salvage surgery (RRT+/-SSx) (Arm II).

RESULTS

Sixty-four of 72 patients were evaluable, 55 were T3 (86%) and 9 were T4 (14%) tumors. In Arm I (n=35) with a mean follow-up of 24 months (2-86 months), 21 patients were alive without disease. Six patients had recurrence, one each at local and tracheostomy stoma, four had nodal recurrence only, and two developed 2nd primary in soft palate/tonsil and parotid at 15 and 18 months respectively. In Arm II (n=29), with a mean follow-up of 24 months (3-81 months), 14 patients were alive without disease. Thirteen patients had recurrence, eight had local (one patient had persistent disease), two nodal only, three loco-regional and two patients developed distant metastasis (lung). One out of eight local recurrence and 2/2 nodal recurrences were salvaged with Sx. There was a significant difference in disease-free survival between the two treatment arms, DFS (5 years) of 70% in Arm I vs 50% in Arm II (p=0.04), but did not have any impact on overall survival OAS (5 years); 73% vs 77% (p=0.79). Voice/laryngeal preservation was possible in 18/29 patients (62%) treated with RRT+/- Sx, without significantly affecting the OAS. "Pathological upstaging" was another significant finding seen in 64% of clinical T3 after radical surgery.

CONCLUSION

RRT+/-SSx can be a feasible option in low volume, favourable resectable stage III and IV supraglottic lesions for better quality of life.

Induction chemotherapy with paclitaxel and cisplatin and CT-based 3D radiotherapy in patients with advanced laryngeal and hypopharyngeal carcinomas--a possibility for organ preservation

BACKGROUND

To evaluate the effect of paclitaxel/cisplatin induction chemotherapy (ICHT) and CT-based radiotherapy (RT) on larynx preservation, tumor control, and survival in patients with larynx/hypopharynx carcinoma eligible for total laryngectomy (TL) or TL plus partial pharyngectomy (TLPP).

PATIENTS AND METHODS

Fifty patients eligible for TL or TLPP were enrolled onto a prospective study and treated with ICHT (200 mg/m(2) paclitaxel, 100 mg/m(2) cisplatin; day 1, 22). In patients with complete or partial tumor response RT (69.9 Gy in 5.5 weeks at the gross tumor, 50.4 Gy in the lymphatic drainage; single dose: 1.8 Gy, concomitant boost: 1.5 Gy) was applied. Non-responders had TL/TLPP and RT with total doses adapted to the radicality of tumor resection (56-70 Gy).

RESULTS

The response rate to ICHT was 88% (10% complete, 78% partial response). At a median follow-up period of 25 months the larynx preservation rate was 84%. The 2-year local-regional control rate was 91% and the 2-year overall survival rate was 72.3%. The 3-year estimate to survive with functional larynx is 60%.

CONCLUSION

In a large portion of patients eligible for TL or TLPP the larynx was preserved by paclitaxel/cisplatin ICHT and 3D RT.

[Volume-effect in radiation therapy part one: volume-effect and tumour]

Volume is an important parameter of radiation therapy. Local control is inversely related to tumor size and the complication rate increases with the importance of the irradiated volume. Although the effect of irradiated volume has been widely reported since the beginning of radiotherapy, it has been less studied than other radiation parameters such as dose, fractionation, or treatment duration. One of the first organ system in which the adverse effect of increased volume was well defined is the skin. Over the last twenty years, numerous mathematical models have been developed for different organs. In this report we will discuss the relation between irradiated volume and tumor control. In a second article we will study the impact of irradiated volume on radiation adverse effects.

Options for Preserving the Larynx in Patients with Advanced Laryngeal and Hypopharyngeal Cancer

The introduction of newer surgical and combined-modality approaches to organ preservation in patients with advanced laryngeal or hypopharyngeal cancer is the most exciting clinical frontier in head and neck cancer-treatment today. The use of these techniques at other sites, the exploration of improved methods for patient selection and tumor assessment, and the development of newer combination regimens will need to be rigorously studied in future clinical trials. In all these efforts, the major focus must remain on improving survival. This article reviews the latest developments in organ-preservation strategies and techniques for patients with advanced laryngeal or hypopharyngeal cancer.

Treatment results and prognostic factors of advanced T3--4 laryngeal carcinoma: the University of California, San Francisco (UCSF) and Stanford University Hospital (SUH) experience

PURPOSE

To review the UCSF-SUH experience in the treatment of advanced T3--4 laryngeal carcinoma and to evaluate the different factors affecting locoregional control and survival.

METHODS AND MATERIALS

We reviewed the records of 223 patients treated for T3--4 squamous cell carcinoma of the larynx between October 1, 1957, and December 1, 1999. There were 187 men and 36 women, with a median age of 60 years (range, 28--85 years). The primary site was glottic in 122 and supraglottic in 101 patients. We retrospectively staged the patients according to the 1997 AJCC staging system. One hundred and twenty-seven patients had T3 lesions, and 96 had T4 lesions; 132 had N0, 29 had N1, 45 had N2, and 17 had N3 disease. The overall stage was III in 93 and IV in 130 patients. Seventy-nine patients had cartilage involvement, and 144 did not. Surgery was the primary treatment modality in 161 patients, of which 134 had postoperative radiotherapy (RT), 11 had preoperative RT, 7 had surgery followed by RT and chemotherapy (CT), and 9 had surgery alone. Forty-one patients had RT alone, and 21 had CT with RT. Locoregional control (LRC) and overall survival (OS) were estimated using the Kaplan--Meier method. Log-rank statistics were employed to identify significant prognostic factors for OS and LRC.

RESULTS

The median follow-up was 41 months (range, 2--367 months) for all patients and 78 months (range, 6--332 months) for alive patients. The LRC rate was 69% at 5 years and 68% at 10 years. Eighty-four patients relapsed, of which 53 were locoregional failures. Significant prognostic factors for LRC on univariate analysis were primary site, N stage, overall stage, the lowest hemoglobin (Hgb) level during RT, and treatment modality. Favorable prognostic factors for LRC on multivariate analysis were lower N stage and primary surgery. The overall survival rate was 48% at 5 years and 34% at 10 years. Significant prognostic factors for OS on univariate analysis were: primary site, age, overall stage, T stage, N stage, lowest Hgb level during RT, and treatment modality. Favorable prognostic factors for OS on multivariate analysis were lower N stage and higher Hgb level during RT.

CONCLUSION

Lower N-stage was a favorable prognostic factor for LRC and OS. Hgb levels > or = 12.5 g/dL during RT was a favorable prognostic factor for OS. Surgery was a favorable prognostic factor for LRC but did not impact on OS. Correcting the Hbg level before and during treatment should be investigated in future clinical trials as a way of improving therapeutic outcome in patients with advanced laryngeal carcinomas.

ORGAN PRESERVATION FOR CARCINOMA OF THE LARYNX AND HYPOPHARYNX

Treatment of laryngeal and hypopharyngeal cancers often necessitates total laryngectomy. This article reviews approaches of curing patients with these diseases while preserving their larynx. Strategies include radiation alone, neoadjuvant chemotherapy with radiation for responders, or concurrent chemotherapy and radiation. Both retrospective experiences and randomized trials evaluating differing therapies in an effort to achieve voice preservation are reported and analyzed.

Management of cancer of the supraglottis

We present the results of a retrospective study of 903 patients treated with conservation surgery for carcinoma of the supraglottic larynx so we can evaluate our management of supraglottic cancer with different types of surgery. In 301 patients, an extended supraglottic laryngectomy was performed. The recent selective use of transoral laser resection appears to be a rational approach. The 5-year uncorrected survival was 84%, 81%, 76%, and 55% for stages I, II, III, and IV, respectively. The most common site for local-regional failure was the cervical lymphatics. The percentage of occult disease in the NO neck was 21% and epilaryngeal supraglottic location, locally advanced and GIII tumors have a higher frequency of lymph node involvement. There were no differences between comprehensive and anterolateral elective neck dissections. A bilateral elective neck dissection is recommended. In histologically positive neck disease, the survival rates were better with postoperative radiotherapy only in cases of extracapsular spread.

Endoscopic laser surgery in the treatment of radiation failure of early laryngeal carcinoma

BACKGROUND

This study was undertaken to analyze the local control rates and survival of patients undergoing endoscopic laser surgery for squamous cell carcinoma of the larynx as a salvage procedure for recurrent tumors after radiotherapy.

METHODS

Twenty-four patients underwent endoscopic laser surgery for radiation failure at our hospital from 1988 to 1995. All patients were men, between 45 and 88 years old. The localization of the recurrence was in the supraglottis in 3 cases and in the glottis in 21 cases. The postirradiation recurrences were staged rT1 in 18 patients and rT2 in 6 patients.

RESULTS

Local recurrence after laser surgery developed in six patients (25%) who had a total laryngectomy. Voice preservation was thus achieved in 75% of patients. No patient died because of the laryngeal cancer, and the observed 5-year survival rate was 76%.

CONCLUSIONS

These results indicate that in selected cases, endoscopic laser surgery may be used successfully for treating radiation failure of early laryngeal carcinomas.

331 cases of clinically node-negative supraglottic carcinoma of the larynx: a study of a modest size fixed field radiotherapy approach

PURPOSE

For node-negative supraglottic carcinoma of the larynx, radiotherapy with surgery in reserve commonly provides very good results in terms of both local control and survival, while preserving function. However uncertainty exists over the treatment of the node-negative neck. Elective whole neck radiotherapy, while effective, may be associated with significant morbidity. The purpose of this study was to examine our practice of treating a modest size, fixed field to a high biologically effective dose and compare it with the patterns of recurrence from other centers that use different dose/volume approaches.

METHODS AND MATERIALS

Over a 10-year period 331 patients with node-negative supraglottic carcinoma of the larynx were treated with radiotherapy at the Christie Hospital Manchester. Patients were treated with doses of 50-55 Gy in 16 fractions over 3 weeks. Data were collected retrospectively for local and regional control, survival, and morbidity.

RESULTS

Overall local control, after surgical salvage in 17 cases, was 79% (T1-92%, T2-81%, T3-67%, T4-73%). Overall regional lymph node control, after surgical salvage in 13 cases, was 84% (T1-91%, T2-88%, T3-81%, T4-72%). Five-year crude survival was 50%, but after correcting for intercurrent deaths was 70% (T1-83%, T2-78%, T3-53%, T4-61%). Serious morbidity requiring surgery was seen in 7 cases (2.1%) and was related to prescribed dose (50 Gy-0%, 52.5 Gy-1. 3%, 55 Gy-3.4%).

DISCUSSION

Our results confirm that treating a modest size, fixed field to a high biologically effective dose is highly effective. It enables preservation of the larynx in most cases, with acceptable regional control and no loss of survival compared to whole neck radiotherapy regimes.

Larynx preservation in head and neck cancers. A discussion of the National Comprehensive Cancer Network Practice Guidelines

The management of advanced cancers of the larynx and hypopharynx has become increasingly complex as different treatment modalities, including surgery, radiation, and chemotherapy, have been combined with the goal of improving local disease control and disease-specific survival. A union of 17 comprehensive cancer centers in the United States, the National Comprehensive Care Network (NCCN), was formed in 1995 to promote state-of-the-art cancer care. To achieve this goal, multidisciplinary panels of experts from member institutions have created disease-specific practice guidelines for the evaluation and treatment of cancer patients, including those with head and neck cancers. Although detailed analysis of surgical methods and radiation techniques are beyond the scope of this article, the evolving laryngeal preservation strategies for patients with advanced, resectable hypopharyngeal or laryngeal (including supraglottic and glottic) cancers are reviewed using relevant sections of the NCCN practice guidelines as a framework for discussion.

Laryngeal preservation by treatment with induction chemotherapy and radiotherapy protocol for stage III & IV carcinoma larynx--results of a pilot study

Total laryngectomy for advanced carcinoma of the larynx is effective but functionally disabling. In an effort at laryngeal preservation, 33 patients of stage III/IV carcinoma larynx were treated between 1987 and 1991 with induction chemotherapy followed by definitive radiation. Two chemotherapy protocols were administered. Group I patients received one to three cycles of cisplatin 100 mg/m2 (day 1), bleomycin 15 U/m2 (day 1), and 5-fluorouracil 1000 mg/m2/day (day 2 to 5) at three weekly intervals. This was then followed by radiotherapy. Group II received one to six weekly injections of single agent methotrexate 50 mg/m2 with or without leucocovorin rescue followed by radiotherapy. Any recurrence was salvaged by surgery. Midway through the study, Group II protocol was discontinued as the initial results were not comparable with Group I or standard treatment. The Group I protocol, however, yielded an initial locoregional control rate of 83.3 per cent With the addition of surgical salvage the locoregional control rate was 94.4 per cent and the control rate with laryngeal preservation was 88.8 per cent. The Kaplan-Meier probability of two years and five years disease-free survival was 81.9 per cent and 61.4 per cent respectively. For disease-free survival with laryngeal preservation the corresponding figures for two years and five years were 58.3 per cent and 41.7 per cent. The control group of 51 patients treated with radical surgery followed by radiotherapy yielded survival figures at two years and five years of 64.3 per cent and 57.2 per cent. The difference in the survival of Group I and the control group was not statistically significant (p value = 0.280). These initial results indicate that for stage III and for surgically resectable stage IV laryngeal carcinomas, a protocol of induction combination chemotherapy consisting of cisplatin, bleomycin and 5-fluorouracil followed by radiotherapy and combined with surgical salvage whenever required, can lead to comparable cure rates. In addition, a large proportion of patients are spared the morbidity of a total laryngectomy.

The effect of heterogeneity in tumor cell kinetics on radiation dose-response. An exploratory investigation of a plateau effect

PURPOSE

To investigate the effect of heterogeneity in tumor cell kinetics on radiation dose-response curves for a population of patients.

MATERIALS AND METHODS

A series of exploratory calculations have been performed using an improved geometric-stochastic model of tumor cure.

RESULTS

Radiation therapy dose-response curves may plateau, or nearly so, at tumor control levels well below 100%, if a proportion of tumors would grow sufficiently fast to counterbalance the effect of fractionated radiotherapy. If the model assumptions of doubling time heterogeneity are correct, the difference between a short and protracted radiation regimen would be not only in the position and steepness of the radiation dose-response curve, but also in the level of the predicted plateau.

CONCLUSIONS

For a given rate of dose accumulation, the one-sided flattening in dose-response curves at high doses is predicted from the modeling, and determined by the proportion of most radioresistant and rapidly growing tumors. This shows that empirical models of tumor control probability which assume a symmetric sigmoid relationship from 0 to 100% have apparent limitations, seemingly not well acknowledged in the literature.

T3-4 squamous cell carcinoma of the larynx treated with radiation therapy alone

This article reviews the results of radiation therapy alone for T3-4 squamous cell carcinoma of the larynx. Local control after radiation therapy is approximately 65% for patients with T3 glottic and supraglottic carcinoma. The likelihood of local control is inversely related to tumor volume and, for those with glottic cancers, is adversely influenced by cartilage sclerosis on pretreatment computed tomography of the larynx. Local control after radiotherapy is approximately 60% for T4 glottic cancers and 50% for T4 supraglottic carcinomas. The probability of severe complications is related to primary site and T-stage.

Larynx preservation trials: a critical appraisal

Controlled trials testing the concept of laryngeal preservation for patients with locally advanced stage III and IV cancers of the larynx or hypopharynx were initiated in the mid-1980s. Three randomized trials, evaluating the same cisplatin plus 5-fluorouracil induction chemotherapy regimen and conventional radiotherapy compared with surgery and radiotherapy, have been completed, and the results of two are published. In addition, a meta-analysis of these three trials was completed. The studies are critically reviewed. Conclusions from these trials are that the induction approach is feasible; local and regional control are not improved, whereas distant metastases are delayed; there is no evidence of a difference in overall survival; and of the patients alive at 3 and 5 years, a functional larynx can be preserved in 67% and 58%; there are not enough data to know if there are differences in outcome by subsite. Several unanswered questions are being addressed in phase III trials. These include defining the precise contribution of chemotherapy by comparing induction chemotherapy and radiotherapy to treatment with radiotherapy alone; determining if elective neck dissection for patients with N2N3 neck disease would improve survival; and determining whether local control can be improved by using concomitant or alternating chemotherapy and radiotherapy.

Elective irradiation of the N0 neck in squamous cell carcinoma of the upper aerodigestive tract

The decision of how to optimally manage the clinically negative neck is based on the likelihood of clinically inapparent disease and the efficacy of salvage therapy. The criteria of decision for elective management of the neck takes into account the site, size, depth of infiltration, grading of the primary lesion, clinical and radiologic evaluation, and patient wishes. Diagnostic procedures currently used in evaluating head and neck cancer patients with nodal disease are reviewed. Elective irradiation of the N0 neck in patients with squamous cell carcinoma of the head and neck is an effective means of maintaining locoregional control. The impact of elective nodal treatment on disease free survival and overall survival is discussed.

Larynx Preservation: The Discussion is not Closed

Advanced but resectable larynx and hypopharynx squamous cell carcinomas are, in the vast majority of cases, treated by radical surgery and postoperative irradiation, resulting in the total ablation of the voice box. Some institutions prefer to use irradiation and reserve radical surgery for salvage. There is no randomized comparison of results obtained with these two strategies. Induction chemotherapy with the use of platinum and 5-fluorouracil provides notable response rates and allows the prediction of radiosensitivity in those patients who show a response to chemotherapy. This has been the basis of the most frequent larynx preservation approach: induction chemotherapy followed by irradiation in good responders or by radical surgery in poor responders. This strategy did not jeopardize survival and allowed larynx preservation in 50% to 66% of survivors. These results are of importance but it should nonetheless be remembered that irradiation is an efficient treatment of these tumors and may have an improved activity (with modified fractionation or concurrent administration of chemotherapy and irradiation) and that selected cases are amenable to subtotal laryngectomy. On the other hand, new prospects for treatment are emerging (biologic tools, place of imaging), as well as new parameters for the success of treatment (quality of life, quality of preserved function, cost effectiveness). In summary, larynx preservation is undoubtedly feasible but remains investigational.

T4 laryngeal carcinoma: radiotherapy alone with surgery reserved for salvage

PURPOSE

To review the results of primary radiation therapy for patients with T4 squamous cell carcinoma of the larynx.

METHODS AND MATERIALS

Between October 1964 and October 1994, 43 patients with T4 invasive squamous cell carcinoma of the larynx received radiotherapy with curative intent in the University of Florida Department of Radiation Oncology. All patients had a minimum of 2 years follow-up. There were 26 primary cancers of the supraglottic larynx, 11 of the glottic larynx, and 6 of the subglottic larynx.

RESULTS

The 5-year actuarial rate of local control was 52%. By direct calculation, local control was achieved in 8 (38%) of 21 supraglottic carcinomas, 8 (89%) of 9 glottic tumors, and 2 of 6 subglottic tumors. Local control of nonbulky lesions was achieved in 67%, and 38% of bulky lesions were locally controlled. Only 3 (17%) of 18 local recurrences were successfully salvaged by subsequent surgery. There were 2 (5%) severe complications of irradiation.

CONCLUSION

From our series, as well as a review of the literature, local control by primary irradiation has been achieved in approximately 50% of patients with T4 laryngeal cancer. Selection factors for choosing irradiation have not been well described: the present series contains a small amount of information suggesting that tumor volume may be a reliable predictor of control, but further substantiation is required.

Conservative management of T1-T2N0 supraglottic cancer: a retrospective study

PURPOSE

Evaluate the results of conservative management of early-stage supraglottic cancer.

PATIENTS AND METHODS

A retrospective analysis of 166 consecutive T1-T2N0 cases of squamous cell carcinoma of the supraglottic larynx, treated conservatively between 1983 and 1992, was performed. Sixty-six patients received conservative surgery (CS), whereas 100 patients received definitive radiation therapy (RT). Surgical procedures included horizontal supraglottic laryngectomy in 38 patients, extended supraglottic laryngectomy in 16 patients, and reconstructive laryngectomy with cricohyoidopexy in 12 patients. Elective bilateral neck dissection was always performed. Radiotherapy was delivered with 60Co or 6 MV photons to the primary laryngeal tumor and the upper and mid neck nodes (level II and III), whereas supraclavicular nodes (level IV) were electively irradiated only in 54 patients with T2N0 tumors. Fifty-two patients received conventional fractionation, whereas 31 patients were irradiated according to a twice-a-day fractionation regimen. The median total tumor dose was 67 Gy (range, 64 to 72 Gy).

RESULTS

The 5-year overall survival of the whole series was 72.7% +/- 4.5. In patients treated with CS, the 5-year disease-free survival was 88.4% +/- 4.5 versus 76.4% +/- 6.1 for patients who received RT. Salvage surgery was effective in rescuing 2 of 3 CS failures and 12 of 25 RT failures. The overall incidence of secondary tumors (11%) and distant metastases (5%) was relatively low, although together they account for 15% of all deaths. Complications of CS were significantly correlated to the extent of surgical procedure. A multivariate analysis performed in the RT group showed that performance status, tumor grade, and fractionation regimen significantly influenced disease-free survival.

CONCLUSION

Conservative management of T1-T2N0 supraglottic cancer, either by CS or RT, can achieve good cure rates with larynx preservation for the majority of the patients (82% overall; 95% in the CS group and 72% in the RT group). The decision between different conservative treatment modalities may be influenced by the patient's conditions, tumor characteristics, treatment modalities, and also economic costs.

Enhanced control by radiotherapy of cervical lymph node metastases arising from nasopharyngeal carcinoma compared with nodal metastases from other head and neck squamous cell carcinomas

PURPOSE

To test the hypothesis that metastatic cervical lymph nodes arising from nasopharyngeal carcinoma (NPC) are more readily controlled with radiotherapy than comparable nodes from squamous cell carcinomas of other head and neck sites (SCC).

METHODS AND MATERIALS

One hundred four NPC patients with metastatic cervical nodes (mean size of the largest node equals 4.1 cm) were randomly selected from radiation treatment files for two time periods, 1969-1976 and 1983-1988, when radiation alone was the first line treatment. Candidate controls were selected randomly from radiation treatment files of node positive squamous cell carcinomas arising from the oropharynx, hypopharynx, oral cavity or larynx who were also treated by radical radiation therapy as sole initial treatment in the 1970s and 1980s. Each NPC case was matched with a control using the size of the largest involved node as the matching criterion. The median follow-up of all 208 patients was 3 years (4.2 years in NPC cases and 1.4 years in the matched controls). For those who were alive at last follow-up, the median follow-up for both arms was 7.7 years (6.7 years in NPC cases and 10.2 years in the matched controls). Nodal control was evaluated by clinical neck examination in both arms. Nodal recurrence was defined as relapse or persistence of metastatic nodal disease from day 1 of radiotherapy treatment.

RESULTS

Despite a similar mean delivered dose to involved neck nodes (52.9 Gy for the NPC group and 53.9 Gy for the matched controls), the SCC group had significantly worse nodal control with radiation when compared to the NPC group (p < 0.0001, relative risk 3.0, 95% [1.8, 5.1]). The 3-year nodal recurrence-free rate among NPC cases was 71 +/- 5%, compared to 43 +/- 5% among matched controls.

CONCLUSION

The result of this study supports the hypothesis that metastatic cervical nodes from NPC are more readily controlled by irradiation than cervical nodes of similar size arising from other head and neck squamous cell carcinomas. Further study is required to explore the reasons for this apparent radiosensitivity.

The "gregorio marañon" hospital experience in the treatment of laryngeal carcinoma

A retrospective analysis has been carried out of 4100 patients with pharyngolaryngeal carcinoma who were seen at the Hospital Gregorio Marañon between 1962 and 1993. 1287 patients were excluded from this study, leaving 2813 patients available for analysis. The great majority of the 2813 pharyngolaryngeal carcinomas were primary laryngeal tumours (2519). These are the subject of our study.We present our theoretic protocol for treatment of laryngeal carcinoma, both glottic and supraglottic, with special attention to the partial surgery. Our oncological and functional results are presented and discussed.

Tumour recurrence or treatment sequelae following radiotherapy for larynx cancer

Differentiating between recurrent carcinoma and significant sequelae of radiotherapy after treatment of laryngeal carcinoma is an uncommon but difficult clinical problem. Head and neck surgeons can be faced with deciding on the necessity for salvage laryngectomy without prior histological confirmation of recurrence. This paper reviews the literature pertaining to this topic to provide a better overall estimate of the risk of recurrence in these cases. Approximately 50% of patients with severe oedema or necrosis following radiotherapy for larynx cancer will have recurrence. Less than 10% of all larynges removed will be histologically negative when persistent or recurrent tumour is suspected clinically or indicated by biopsy following radiotherapy.

An observer study for direct comparison of clinical efficacy of electronic to film portal images

PURPOSE

To directly compare clinical efficacy of electronic to film portal images.

METHODS AND MATERIALS

An observer study was designed to compare clinical efficacy of electronic to film portal images acquired using a liquid matrix ion-chamber electronic portal imaging device and a conventional metal screen/film system. Both images were acquired simultaneously for each treatment port and the electronic portal images were printed on gray-level thermal paper. Four radiation oncologists served as observers and evaluated a total of 44 sets of images for four different treatment sites: lung, pelvis, brain, and head/neck. Each set of images included a simulation image, a double-exposure portal film, and video paper prints of electronic portal images. Eight to nine anatomical landmarks were selected from each treatment site. Each observer was asked to rate each landmark in terms of its clinical visibility and to rate the ease of making the pertinent verification decision in the corresponding electronic and film portal images with the aid of the simulation image.

RESULTS

Ratings for the visibility of landmarks and for the verification decision of treatment ports were similar for electronic and film images for most landmarks. However, vertebral bodies and several landmarks in the pelvis such as the acetabulum and public symphysis were more visible in the portal film images than in the electronic portal images.

CONCLUSION

The visibility of landmarks in electronic portal images is comparable to that in film portal images. Verification of treatment ports based only on electronic portal images acquired using an electronic portal imaging device is generally achievable.

Prognostic factors of local control after radiotherapy in T1 glottic and supraglottic carcinoma of the larynx

This study presents a retrospective analysis of a consecutive series of 161 patients treated with curatively intended radiotherapy for T1 supraglottic or glottic carcinoma from 1972 to 1990 at the Department of Oncology, Aalborg County Hospital, Denmark. All patients received radiotherapy given with 4-MV X-rays on lateral opposed fields. Intended dose was 60 Gy in 30 fractions. Multivariate analysis of recorded clinical parameters was applied to identify possible prognostic factors of local control. Tumor size, differentiation grade and sex were identified as significant independent prognostic parameters of local control. Five-year local control was 58% and 78% for supraglottic and glottic tumors, respectively. Applying salvage surgery the ultimate control rates were 82% and 97% for supraglottic and glottic tumors, respectively. Evaluation of treatment response 3-6 weeks following accomplishment of radiotherapy demonstrated that remaining tumor at the time of evaluation was an indicator of failure in local control.

Volume and heterogeneity dependence of the dose-response relationship for head and neck tumours

Based on the Poisson statistics of cell kill a model for the response of heterogeneous tumours to non-uniform dose delivery have been developed. The five parameters required to characterize the response are the 50% response dose, D50, the normalized dose-response gradient, gamma, the tumour heterogeneity factor, h, the relative volume, v and the extra daily dose required to counteract the tumour cell proliferation, delta. The model has been fitted to data from a number of clinical investigations to allow the derivation of clinically relevant radiation response parameters for head and neck tumours. The D50 value for T2 larynx cancers is 59.9 Gy in 41 days with a relative standard deviation of 2.1 Gy and the gamma value is 2.9 with a relative standard deviation of 0.3. The value of delta, which is most consistent with the clinical data for laryngeal tumours, is 0.35 Gy/day and this value should be used if the treatment time is changed from the 41 days normalization. The heterogeneity factor, h, is close to zero for laryngeal tumours which indicates that their response is basically governed by Poisson statistics. Nasopharyngeal tumours, on the other hand, exhibit h values around 0.2 which indicates that these tumours are more heterogeneous in their internal organization and so are their responses to radiation.

Clinical use of on-line portal imaging for daily patient treatment verification

PURPOSE

To determine the ease of use by clinical staff and reliability of an electronic portal imaging system and evaluate the potential to utilize on-line imaging to assess accuracy of daily patient treatment positioning in radiation therapy.

METHODS AND MATERIALS

A computer controlled fluorescent screen-mirror imaging system was used to acquire on-line portal images. A physician panel assessed on-line image quality relative to standard portal film. Clinical use of the imager was implemented through a protocol where images were obtained during the first six monitor units of external beam. The images were visually compared to a reference portal and patient setup was adjusted for errors exceeding 5 mm. Subsequent off-line analysis was utilized to give insight into the magnitude of clinical setup error in the visually accepted images.

RESULTS

Physician evaluation of on-line image quality with an initial 211 images found that 70% were comparable or superior to standard film portal images. Eighty percent of treatment fields fit completely within the on-line imaging area. Eight percent of on-line images were rejected due to poor image quality. Twelve percent of the daily treatment setups imaged required adjustment overall, but specific field types predictably required more frequent adjustment (pelvic and mantle fields). Off-line analysis of accepted images demonstrates that 18% of the final images had setup errors exceeding 5 mm.

CONCLUSION

On-line imaging facilitated daily portal alignment and verification. Ease of use, almost instantaneous viewing and consistent ability to identify and locate anatomical landmarks imply the potential for on-line imaging to replace film based approaches. Retrospective analysis of daily images reveals that visual assessment of setup is not sufficient for eliminating localization errors. Further improvement is required with respect to detecting localization error and fully encompassing larger field sizes.

Dose, fractionation and overall treatment time in radiation therapy--the effects on local control for cancer of the larynx

The effect of total tumor dose, split course treatment and overall treatment time on local control was analysed in a retrospective series of 997 patients with carcinoma of the larynx, treated with megavoltage radiotherapy only. Primary tumors were classified by site (glottis and supraglottis) and T-stage. Continuous course (CC, n = 594) treatment was given primarily to small tumors. Split course radiation (SC, n = 403) was generally given to patients with larger field sizes. Total doses of irradiation ranged from 50 to 79 Gy, with a mean of 64 Gy in CC and 66 Gy in SC. Most of the treatments were given with fraction sizes between 2.0 and 2.1 Gy (91%). Overall treatment times ranged between 25 and 60 days in the CC group (mean, 45 days) and between 45 and 120 in the SC group (mean, 76 days). A local recurrence was observed in 256 patients. T-stage was the only tumor characteristic strongly related to local failure. Corrected for T-stage, no difference in local relapse rate was observed between glottic and supraglottic tumors, or between node-negative (n = 886) and node-positive patients (n = 111). After correction for T-stage the local failure rate of SC-treated tumors was 2.1 (95% confidence limits: 1.4-3.1) times higher than of CC-treated tumors. However, this effect could not be explained as an effect of the overall treatment time (OTT) itself, as no effect of OTT was found within the SC and the CC group, even though the variation in OTT's was considerable in the SC group. A higher tumor dose was associated with a lower local failure rate in the CC group (p = 0.005), but not in the SC group (p = 0.56).

Couch rotation technique for treatment of head and neck cancer

This paper reviews a technique for patients with head and neck cancer that achieves adequate inferior margins on the lateral ports by rotating the treatment couch. This technique has the advantage of avoiding multiple ports in an area of high risk or over a tumor mass.

Can modest escalations of dose be detected as increased tumor control?

Clinically defined groups of tumors are usually characterized by shallow dose-response curves, and this results from heterogeneity among individual dose-response curves, each of which is very likely quite steep. A review of published results for human tumors indicates that a 10% escalation of dose to tumors controlled at the 50% level, where changes in outcome are most likely to be detected, will be detectable in a population of unselected patients only in sizable clinical trials (130-300 patients per dose level). With a few exceptions, a dose escalation of 20% will be detectable in much smaller trials (50-130 patients per dose level). Therefore, clinical trials of improved treatment modalities will be confounded by patient heterogeneity, and modest improvements may go undetected in all but the largest trials. Mathematical modeling was used to study the effect on the steepness of the dose-response curve of selecting patients on the basis of the radiosensitivity measure SF2 (surviving fraction at 2 Gy). If SF2 is a faithful predictor of response in a group of tumors, then heterogeneity could be reduced by excluding the patients with the most sensitive (controlled with near certainty) and most resistant (recurring with near certainty) tumors. The resulting "stochastic fraction" (tumors for which treatment outcome is probabilistic) would be characterized by a steep dose response, and the number of patients required to demonstrate the effect of dose escalation would be substantially reduced (by about 50%).

Radiotherapy in T1 laryngeal cancer: prognostic factors for locoregional control and survival, uni- and multivariate analysis

From 1975 through 1985, 194 patients with T1 glottic, 37 patients with T1 supraglottic, and 3 patients with T1 subglottic cancer were treated with radiotherapy. Local control and ultimate locoregional control (after salvage surgery) was 91% and 97% for T1 glottic, 84% and 81% for T1 supraglottic, and 2/3 and 3/3, respectively for subglottic tumors. In uni- and multivariate analysis local control for glottic tumors was associated with extension of the tumor on the vocal cord (entire length of vocal cord vs others, p = 0.01) and continuation of smoking after therapy (yes/no, p = 0.03). No prognostic factor for local control was found in supraglottic tumors. However, regional control and survival were impaired by N stage (N0 vs N+, p less than 0.0005), local recurrence (yes/no, p less than 0.0005), and extension of the tumor (one supraglottic subsite vs more than one, p less than 0.05). Mild late complications were seen in 13% of patients without salvage therapy. Following univariate analysis, field size, fraction size (greater than 2 Gy), maximum tumor dose (greater than 70 Gy), age, post-treatment biopsy, and tumor site were associated with complication rate. Following multivariate analysis, site, fraction size, maximum tumor dose, and continuation of smoking after therapy were independent prognostic factors for mild late complications (mostly arytenoid edema).