Local control in T3 laryngeal cancer treated with radical radiotherapy, time dose relationship: the concept of nominal standard dose and linear quadratic model

Why to start the concomitant boost in accelerated radiotherapy for advanced laryngeal cancer in week 3

PURPOSE

We analyzed toxicity and the local control rates for advanced laryngeal cancer, treated with two accelerated fractionation schedules. The main difference between the schedules was the onset of the concomitant boost, in Week 3 or Week 4. Overall treatment time and total dose were equivalent.

METHODS AND MATERIALS

In a prospective, nonrandomized study of T3, T4, and advanced T2 laryngeal cancer, concomitant boost schedules were used in 100 patients. Thirty patients received a schedule of twice daily 1.2 Gy in Weeks 1-3, followed by twice daily 1.7 Gy in Weeks 4 and 5; total dose was 70 Gy (the hyperfractionated accelerated schedule [HAS] regimen). Seventy patients were treated with 5 times 2 Gy in Weeks 1 and 2, followed by daily 1.8 Gy and 1.5 Gy (boost) in Weeks 3-5; total dose 69.5 Gy (the accelerated schedule only [ASO] regimen). Distribution of T stage was 47%, 40%, and 12% for T2, T3, and T4, respectively. In 24% of the patients, lymph nodes were positive. Pretreatment tracheotomy or stridor or both occurred in 8 patients. The distribution of prognostic factors was not significantly different between the two fractionation schedules. Acute and late toxicity was assessed. Results were estimated by the use of actuarial methods. For late toxicity and local control univariate and multivariate analyses were performed. Tumor control probability analysis was used to model cure rate differences.

RESULTS

Overall acute mucositis score was equal for both schedules. Acute mucositis started and decreased significantly earlier in the HAS regimen. In all patients acute mucositis healed completely. The treatment was completed within 38 days in all patients. The regional control rate was 100% for clinical N0, and 75% for the clinical N+ patients. The 3-year local control rate was 59% and 78% for the HAS and ASO regimens, respectively (p = 0.05); the ultimate local control was 80% and 94%, respectively. In multivariate analysis, besides the fractionation schedule (relative risk [RR], 2.6 for HAS vs. ASO), pretreatment tracheotomy/stridor (RR 4.3, yes vs. no), and local tumor response 3-6 weeks after radiotherapy (RR 5.1, no vs. yes) were independent factors for local control. Tumor control probability analysis indicated that the onset of repopulation may be about 4-6 days earlier for the HAS regimen. The onset of repopulation in the HAS regimen is probably at the end of the second week or at the beginning of the third week. Severe late toxicity was observed in the HAS group and ASO group in, respectively, 11% and 16%. In multivariate analysis this toxicity related significantly to the field size and pretreatment tracheotomy/stridor.

CONCLUSIONS

In our study the timing of the boost in accelerated radiotherapy for advanced laryngeal cancer was an independent factor for local control, favoring the use of a concomitant boost in Week 3. This finding may indicate that accelerated repopulation of tumor cells starts early in the treatment phase.

Carcinoma of the larynx: the Dutch national guideline for diagnostics, treatment, supportive care and rehabilitation

PURPOSE

This evidence based guideline aims to facilitate proper management and to prevent diverging views concerning diagnosis, treatment and follow-up of carcinoma of the larynx between the major referral centers for head and neck cancer in The Netherlands.

METHOD

A multidisciplinary committee was formed representing all medical and paramedical disciplines involved in the management of laryngeal cancer and all head and neck oncology centers in The Netherlands. This committee reviewed the literature and formulated statements and recommendations based on the level of evidence and consistency of the literature data. Where reliable literature data were not available, recommendations were based on expert opinion.

RESULTS

Strict criteria have been proposed for the radiological diagnostic procedures as well as for the pathology report. For carcinoma in situ and severe dysplasia, microsurgery, preferably by laser, is proposed. For all other stages of invasive carcinoma, a full course of radiotherapy as a voice conserving therapy is the treatment of choice. Only in cases with massive tumor volumes with invasion through the laryngeal skeleton, primary surgery is inevitable. For rehabilitation and supportive care, minimal criteria are described. Due to the complexity of therapy and relative rarity of larynx carcinoma, all patients should be seen at least once in a dedicated head and neck clinic.

CONCLUSION

This guideline for the management of larynx carcinoma was produced by a multidisciplinary national committee and based on scientific evidence wherever possible. This procedure of guideline development has created the optimal conditions for nationwide acceptance and implementation of the guideline.

F-18-fluoro-deoxy-glucose positron-emission tomography scanning in detection of local recurrence after radiotherapy for laryngeal/ pharyngeal cancer

BACKGROUND

The objective of this investigation was to determine whether F18-fluoro-deoxy-glucose (FDG) positron-emission tomography (PET) could differentiate between local recurrence and late radiation effects after radiotherapy for laryngeal/pharyngeal cancer.

METHODS

In a prospective study of 75 patients (67 larynx, eight oro/hypopharynx), 160 laryngoscopies and 109 FDG PET scans were performed on the head and neck region. The mean follow-up time after the first FDG PET scan was 23 months (minimum 1 year).

RESULTS

Local recurrence was diagnosed in 37 patients: 19 after the first biopsy and 18 after follow-up biopsies. For all of the negative initial FDG scans (27), the biopsies that were taken at the same time were negative and no recurrence was seen for at least 1 year. The first FDG scan was a true positive in 34 of 48 patients. In 12 of the 14 patients with false-positive results, FDG scans were repeated; a decreased FDG uptake was found in 9 of the 12. The sensitivity and specificity of the first scan were respectively 92% and 63%; including subsequent FDG scans, the rates were 97% and 82%, respectively.

CONCLUSIONS

When a local recurrence is suspected after radiotherapy for cancer of the larynx/pharynx, an FDG PET scan should be the first diagnostic step. No biopsy is needed if the scan is negative. If the scan is positive and the biopsy negative, a decreased FDG uptake measured in a follow-up scan indicates that a local recurrence is unlikely.

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.

Clinical outcome and tumour microenvironmental effects of accelerated radiotherapy with carbogen and nicotinamide

Experimental studies have shown an almost 2-fold increase in effectiveness if accelerated radiotherapy combined with carbogen and nicotinamide (ARCON) was compared with standard radiotherapy. This combination was chosen in order to overcome repopulation of clonogens during radiotherapy and to minimize tumour hypoxia. Analysis of microenvironmental parameters is required to identify tumours that can benefit from these new treatment approaches. In this study 124 patients with stage III or IV head and neck squamous cell carcinomas received ARCON treatment. Vascular architecture, perfusion, proliferation and oxygenation were studied in two human laryngeal squamous cell carcinoma xenograft lines and the effects of carbogen and nicotinamide were analysed. Loco-regional control for stage III-IV larynx carcinomas was 85%, for hypopharynx carcinomas 50% and for oral cavity and oropharynx carcinomas 65%. In the experimental studies, carbogen treatment resulted in one tumour line in a decrease of blood perfusion, which was reversed if nicotinamide was added. The other tumour line showed no perfusion changes after carbogen or nicotinamide treatment. Both tumour lines showed a drastic reduction of hypoxia after carbogen breathing only or carbogen breathing plus nicotinamide. The ARCON schedule results in high loco-regional tumour control rates. Analysis of tumour microenvironmental parameters showed differences in response to carbogen and nicotinamide between different tumour lines of similar histology and site of origin. This indicates that it may be advantageous to base the selection of patients for oxygenation modifying treatment on microenvironmental tumour characteristics.

[Organ preservation in ORL oncology: myth or reality. The case for laryngeal preservation]

The conservation of a functional larynx is an important goal in the various attempts to improve the treatment of locally-advanced pharyngo-laryngeal cancers. Several axes have been followed: conservative surgery (subtotal laryngectomy), exclusive irradiation (with conventional or non-conventional fractionation), initial chemotherapy (followed by surgery or irradiation) or concomitant chemotherapy-radiotherapy. The numerous studies, including some major randomised trials, dealing with the issue of larynx preservation are reviewed in the present article. A critical comparison of their results and its integration in a consistent approach are difficult, especially because the different options are aimed at different patients. Total laryngectomy and its psychological and social consequences can be avoided in a significant number of patients, although the long term functional outcome is poorly known and the choice of the optimal treatment modality is largely dependent on the expertise and experience of the medical team.

Accelerated radiotherapy with carbogen and nicotinamide (ARCON) for laryngeal cancer

BACKGROUND AND PURPOSE

Tumor hypoxia and tumor cell repopulation are known factors determining radiation response. Accelerated radiotherapy as a method to counteract cellular repopulation was combined with carbogen (95% O2 + 5% CO2) breathing and oral administration of nicotinamide as a means to improve tumor perfusion and oxygenation. The feasibility, toxicity and clinical effectiveness of this approach as a voice-preserving treatment for carcinoma of the larynx was assessed in a prospective study.

PATIENTS AND METHODS

Sixty-two patients with stage III-IV laryngeal carcinoma were treated with a schedule of accelerated radiotherapy. The total radiation dose to the primary tumor was 64 Gy and that to the metastatic nodes was 68 Gy delivered in fractions of 2 Gy over 35-37 days. Radiotherapy was combined with carbogen breathing in the initial 11 patients and with both carbogen and nicotinamide administration in the subsequent 51 patients.

RESULTS

After a median follow-up of 24 months, the actuarial local control rate at 2 years was 92%. This is higher than any previous report in the literature for this category of patients. Five patients had a local tumor recurrence and underwent laryngectomy. There was one regional recurrence. Including salvage surgery the loco-regional control rate was 100%. Four patients developed distant metastases and died. The actuarial overall survival rate at 2 years was 85%. Toxicity was increased relative to conventional radiotherapy but was considered as acceptable. One patient underwent laryngectomy for radiation-induced cartilage necrosis.

CONCLUSION

These preliminary results indicate that advanced laryngeal cancer can be controlled in a high proportion of patients when treated with accelerated radiotherapy combined with carbogen and nicotinamide. This approach offers excellent possibilities for larynx preservation.

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.

Local tumor control in radiation therapy of cancers in the head and neck

BACKGROUND

A retrospective study of 1,493 head and neck cancer patients was designed to test current radiobiological thinking, postulating the detrimental effect of protracted overall treatment times (OTT) and/or split course (SC) regimes in radiation therapy on local tumor control.

METHODS

Primary squamous cell carcinomas of the oral cavity (OC), oropharynx (OP), hypopharynx (HP), nasopharynx (NP), and larynx radiated with a dose of at least 50 Gy were analyzed. Those patients treated by brachytherapy and/or primary surgery were excluded. A detailed analysis of the 997 cancers of the larynx was recently published. This paper focuses on the relationship between local tumor control and treatment characteristics for the 496 tumors originating from the OC, OP, HP, and NP. Total doses of radiation ranged from 50 to 79 Gy, with a mean of 64 Gy.

RESULTS

A local failure (LF) was observed for 278 patients. Using Cox regression analysis, T stage and site were strongly related to LF. Corrected for T stage and with reference to OP, tumors in the NP, HP, and OC had a relative LF rate of 0.5, 1.6, and 1.8, respectively. Patients treated with continuous course (CC) and higher doses of radiation therapy fared best. No association was found with OTT and the use of chemotherapy.

CONCLUSIONS

The results observed for the OC, OP, HP, and NP are in line with the findings for the larynx. Analyzing all 1,493 patients, for SC regimes lower local control rates were observed as opposed to the CC treatment series. Moreover, for the normalized total doses, a dose-effect relationship could be established. This study corroborates that disruption of the treatment per se and/or the use of suboptimal total doses of RT are detrimental; it is argued that these observations could be of relevance when designing combined modality protocols.

Radiation therapy for T1,2 glottic carcinoma: impact of overall treatment time on local control

PURPOSE

Local control probabilities of T1,2 glottic laryngeal cancer were evaluated in relation to dose and fractionation of radiation therapy (RT).

MATERIALS AND METHODS

Between 1975 and 1993, 96 T1N0M0 glottic cancers and 32 T2N0M0 glottic cancers were treated with definitive RT. Total RT dose was 60-66 Gy/2 Gy for most of the T1 and T2 tumors, although 10 T2 tumors were treated with hyperfractionation (72-74.4 Gy/1.2 Gy bid). Of the 128 patients, 90 T1 glottic tumors and 30 T2 glottic tumors were followed for > 2 years after treatment. Multivariate analyses using the Cox proportional hazards model and a logistic regression analysis were performed to evaluate the significance of prognostic variables on local control.

RESULTS

The 5-year local control probability for T1 tumors was 85%, whereas that for T2 tumors was 71%. Multivariate analyses demonstrated that only overall treatment time (OTT) was a significant variable for local control. Total RT dose, normalized total doses at a fraction size of 2 Gy, and fraction size were not significant. Local control probability of T1 tumors with an OTT of 42-49 days was significantly higher than that of tumors with an OTT of > 49 days (P < 0.02). Only a 1-week interruption of RT, due to holidays, significantly reduced the 5-year local control probability of T1 glottic tumors from 89 to 74% (P < 0.05).

CONCLUSIONS

These results indicate that OTT is a significant prognostic factor for local control of T1 glottic tumors.

Head and neck cancer

This synthesis of the literature on radiotherapy for head and neck cancer is based on 424 scientific articles, including 3 meta-analyses, 38 randomized studies, 45 prospective studies, and 246 retrospective studies. These studies involve 79174 patients. The literature review shows that radiotherapy, either alone or in combination with surgery, plays an essential role in treating head and neck cancers. When tumors are localized, many tumor patients can be cured by radiotherapy alone and thereby maintain full organ function (1, 2). Current technical advancements in radiotherapy offer the potential for better local tumor control with lower morbidity (3). This, however, will require more sophisticated dose planning resources. To further improve treatment results for advanced tumors, other fractionation schedules, mainly hyperfractionation, should be introduced (5). This mainly increases the demands on staff resources for radiotherapy. The combination of radiotherapy and chemotherapy should be subjected to further controlled studies involving a sufficiently large number of patients (4, 5). Interstitial treatment (in the hands of experienced radiotherapists) yields good results for selected cancers. The method should be more generally accessible in Sweden. Intraoperative radiotherapy should be targeted for further study and development.

Treatment decisions in T3N0M0 glottic carcinoma

PURPOSE

To analyze the results of T3N0M0 glottic carcinoma treated with radiotherapy, surgery, or both.

METHODS AND MATERIALS

The records were retrospectively reviewed of 97 patients with this tumor subsite and stage seen for treatment at the Queensland Radium Institute over a 29-year period. The results for radiotherapy with surgical salvage of failure (XRT/SS) were compared to those with surgery with or without radiotherapy (SURG/SURG+XRT). For those treated initially with radiotherapy alone, the results for different ranges of biologically equivalent doses were compared. These results were compared to those of other published studies.

RESULTS

The 5-year disease-specific survival rats for the XRT/SS and SURG/SURG+XRT groups were 50% and 58%, respectively; this difference is not significant. For the XRT/SS group, there was a trend towards improved 5-year recurrence-free survival (73%) and 5-year disease-specific survival (86%) in those treated to a dose equivalent to 60-64 Gy in 2 Gy fractions, when compared with higher or lower dose equivalents.

CONCLUSION

A group of patients with T3N0M0 glottic carcinoma is specified for which the option of radiotherapy offers a similar chance of survival to those treated surgically. More than 50% of the XRT/SS survivors will retain their larynx.

Laryngectomy alone for T3 glottic cancer

BACKGROUND

The long-term survival of 81 patients with T3 squamous cell carcinoma of the glottic larynx treated with laryngectomy alone is presented and pathologic predictors for cancer recurrence above the clavicles and cancer death are identified.

METHODS

Clinical records, operative notes, and pathologic slides were reviewed. The major end points were failure above the clavicles, cause-specific survival, and overall survival. All patients were followed until death or a minimum of 10.8 years.

RESULTS

The main pattern of treatment failure was within an undissected ipsilateral or contralateral neck. Subglottic extension and nodal metastases predicted failure above the clavicles and delayed metastasis within an undissected neck. The 5-year rate of control of disease above the clavicles, cause-specific survival, and overall survival were 74.1%, 73.7%, and 54.3%, respectively.

CONCLUSIONS

Patients treated with laryngectomy for T3 glottic cancer who have pathologic evidence of subglottic extension or nodal metastasis are at higher risk for recurrence above the clavicles, particularly within an undissected neck.

Does prolonged treatment course adversely affect local control of carcinoma of the larynx?

PURPOSE

The purpose of this paper is to present local control rates of carcinoma of the larynx in relation to the total treatment course after radical radiation therapy.

METHODS AND MATERIALS

A total of 1350 patients with laryngeal carcinoma treated at the Massachusetts General Hospital for the past three decades were available for analysis. Treatment courses were divided into two groups: 45 days and > 45 days. The local control rates were compared and evaluated for statistical differences.

RESULTS

The data indicated that prolonged treatment course adversely affects local tumor control of both advanced glottic and supraglottic lesions, but to a lesser degree for the early tumors.

CONCLUSION

The study indicated that for optimal local control, radiation treatment should be completed as soon as possible, preferably within 6.5 weeks, either by once- or twice-daily accelerated programs. The local control of early T1 glottic cancer has been exceedingly satisfactory by conventional once-daily radiation therapy. Further improvement by shortening of treatment time for such early lesions will be difficult to assess without a prospective randomized trial.

A clinical audit of glottic cancer in Nova Scotia: a paradigm for effectiveness research

We conducted a clinical audit of the recurrence-free rates and absolute survival of 146 patients who presented with T1-T3 glottic cancer and received primary radiotherapy treatment at the Nova Scotia Cancer Centre between 1984 and 1990. The outcomes are compared with a review of published results from other centres. We used stage T3 glottic cancer as an example to illustrate concepts of effectiveness research which are used to determine at what level interventions operate in the day to day practice of medicine. The actuarial recurrence-free rates at 5 years are: T1 91%, T2 73%, and T3 44%. The actuarial absolute survival rates are: T1 84%, T2 68%, and T3 52%. Effectiveness research may utilize efficacy research, clinical audit, quality of life assessment and decision making theory. Its objective is to aid the implementation of appropriate clinical management for specific individuals and defined communities. Expert computer systems may be necessary to synthesize the data and to enhance communication and decision making.

T3 laryngeal cancer, primary surgery vs planned combined radiotherapy and surgery

The Dutch Co-operative Head and Neck Oncology Group performed a retrospective, nationwide study of laryngeal cancer between 1975 and 1984. The results for T3 laryngeal cancer treated with primary laryngectomy (n = 137) with post-operative radiotherapy when indicated or planned combined (pre-operative) radiotherapy with laryngectomy (n = 113) are analysed. The disease-free survival independent prognostic factors were treatment modality (planned combined treatment fared better, P = 0.001), incomplete resection of disease (P = 0.006), positive lymph nodes in the neck dissection specimen (P = 0.03) and poor differentiation (P = 0.04). Local control (95% vs. 85%, P = 0.01) as well as regional control (96% vs. 79%, P = 0.0001) was improved in the combined group compared with the primary laryngectomy group. Regional control was 69% for N0 patients if the neck nodes were not treated electively, compared with 98% for the planned combined treatment group. It is concluded that elective treatment of the neck nodes in T3 laryngeal cancer is mandatory. Radiotherapy is preferred, since as well as regional control, local control will also improve.

Prognostic factors for survival in patients with T3 laryngeal carcinoma

In a total of 511 patients with T3,N0-3,M0 laryngeal carcinoma, 24 possible prognostic factors were analyzed retrospectively. The factors were age, sex, mode of treatment, duration of several clinical symptoms, the presence of sore throat, otalgia, dyspnea, and dysphagia, previous tracheotomy, tumor extension, lymph node status (five items), histologic grading, smoking habits, and alcohol intake. For 300 patients in whom surgery was part of the primary treatment, pathologic staging of the primary tumor and of lymph nodes in neck dissection specimens, cartilage invasion, radicality of the operation, differentiation grade, and subglottic extension ware also evaluated. In a univariate analysis for the whole group, tumor extension (limited to the glottic region), lymph node status (clinically palpable lymph nodes, cytologically confirmed positive lymph nodes), level of lymph node metastasis (high and midjugular site), histologic grading (poor differentiation grade), and treatment modality (planned combined therapy) were considered to be prognostic factors of corrected actuarial survival. In the group that underwent surgery, all factors derived from specimens of the larynx and neck dissections had prognostic significance. Multivariate analysis revealed that the glottic site of the tumor, the presence of cyto- and histopathologically proven metastatic lymph nodes, pretreatment tracheotomy, positive resection margins, and planned combined treatment had a significant influence on corrected actuarial survival.

T3 laryngeal cancer: a retrospective study of the Dutch Head and Neck Oncology Cooperative Group: study design and general results

511 Patients with T3 N0-3 M0 squamous cell carcinoma of the larynx, treated in the Netherlands from 1975 until 1984, were retrospectively analysed. Four different treatment policies were followed: primary surgery, planned combination of radiotherapy and surgery, primary radical radiotherapy, and selective radiotherapy. General results are presented. Local control rate was 72%. Regional control rate was 90% for clinically N0 patients and 78% for clinically N+ patients. Salvage therapy was overall successful in 38%. Surgical salvage for local radiation failures (with regional relapse) was successful in 69%, and for regional failures (without local relapse) in 46%. Ultimate locoregional control was 78% and, due to 8% distant metastases, 5-year actuarial corrected survival was 70%. Prognosis did not improve over the years. Corrected survival was independently correlated with tumour extension, involvement of neck nodes and treatment strategy. Corrected survival was similar for primary radiotherapy and primary surgery, but significantly better for planned combined therapy. Multiple primary tumours occurred significantly more often in male (19.5%) than in female patients (7.3%) (P = 0.05), the bronchus being most commonly affected. Cumulative actuarial risk for metachronous tumour was 15% after 5 years and 30% after 10 years so prevention and early detection of these second tumours may play the most important role in improving overall survival rates in the future.

Stage T3 squamous cell carcinoma of the glottic larynx: a comparison of laryngectomy and irradiation

One-hundred eighteen patients with previously untreated T3 squamous cell carcinoma of the glottic larynx were treated with curative intent between March 1965 and November 1988 at the University of Florida. All patients were observed for at least 2 years and 83% were observed for 5 or more years. Fifty-three patients were treated with irradiation alone and 65 patients were treated with surgery alone (32) or combined with irradiation (33). Thirty-two patients treated with irradiation alone had twice-daily fractionation and the remainder had once-daily fractionation. The local-regional control rates, including patients successfully salvaged after a local-regional recurrence, were 81% after irradiation alone and 81% after surgery alone or combined with adjuvant irradiation. The local control rates for patients treated with irradiation alone were 53% after once-daily fractionation and 71% after twice-daily fractionation. There was no relationship between vocal cord mobility at 5000 cGy, at the end of radiotherapy, or at 1 month after treatment and subsequent local control. The 5-year cause-specific survival rates were 74% for patients treated with irradiation alone and 63% for patients treated surgically. The incidence of severe complications, including those associated with salvage procedures, was 15% for both treatment groups. The rates of laryngeal voice preservation were 66% after irradiation alone and 2% after surgery. Irradiation alone for selected patients with T3 glottic cancer resulted in similar rates of local-regional control, survival, and severe complications, with a significantly higher likelihood of voice preservation, compared with surgery.