Hyperfractionated compared with conventional radiotherapy in oropharyngeal carcinoma: an EORTC randomized trial

Altered-fractionated radiotherapy in locally advanced head and neck cancer

PURPOSE OF REVIEW

To revisit the biologic rationale, the clinical methodology, the outcome and perspectives of altered fractionation in head and neck oncology.

RECENT FINDINGS

Various prospective trials and meta-analyses clearly underline the major benefit patients with locally advanced disease draw from hyperfractionation and the need for an adequate selection of time-dose factors to optimize therapeutic index for accelerated regimens. In addition, the advent of high-precision techniques such as intensity-modulated radiation therapy is bound to favor the development of more intensive regimens of irradiation in the management of locally advanced head and neck squamous cell carcinomas.

SUMMARY

Altered fractionation, both as stand-alone strategy or as part of approaches combining radiation to systemic treatments, is offering a lot of opportunities to the radiation oncologist. Its role is likely to gain ground in all high-risk patients not amenable to systemic treatments, or for whom the high toxicity of chemotherapy is not justified, in case, for instance, of intermediate-risk disease.

Interventions for the treatment of oral cavity and oropharyngeal cancer: radiotherapy

BACKGROUND

The management of advanced oral cavity and oropharyngeal cancers is problematic and has traditionally relied on surgery and radiotherapy, both of which are associated with substantial adverse effects. Radiotherapy has been in use since the 1950s and has traditionally been given as single daily doses. This method of dividing up the total dose, or fractionation, has been modified over the years and a variety of approaches have been developed with the aim of improving survival whilst maintaining acceptable toxicity.

OBJECTIVES

To determine which radiotherapy regimens for oral cavity and oropharyngeal cancers result in increased overall survival, disease free survival, progression free survival and locoregional control.

SEARCH STRATEGY

The following electronic databases were searched: the Cochrane Oral Health Group's Trials Register (to 28 July 2010), CENTRAL (The Cochrane Library 2010, Issue 3), MEDLINE via OVID (1950 to 28 July 2010) and EMBASE via OVID (1980 to 28 July 2010). There were no restrictions regarding language or date of publication.

SELECTION CRITERIA

Randomised controlled trials where more than 50% of participants had primary tumours of the oral cavity or oropharynx, and which compared two or more radiotherapy regimens, radiotherapy versus other treatment modality, or the addition of radiotherapy to other treatment modalities.

DATA COLLECTION AND ANALYSIS

Data extraction and assessment of risk of bias was undertaken independently by two or more authors. Study authors were contacted for additional information as required. Adverse events data were collected from published trials.

MAIN RESULTS

30 trials involving 6535 participants were included. Seventeen trials compared some form of altered fractionation (hyperfractionation/accelerated) radiotherapy with conventional radiotherapy; three trials compared different altered fractionation regimens; one trial compared timing of radiotherapy, five trials evaluated neutron therapy and four trials evaluated the addition of pre-operative radiotherapy. Pooling trials of any altered fractionation radiotherapy compared to a conventional schedule showed a statistically significant reduction in total mortality (hazard ratio (HR) 0.86, 95% confidence interval (CI) 0.76 to 0.98). In addition, a statistically significant difference in favour of the altered fractionation was shown for the outcome of locoregional control (HR 0.79, 95% CI 0.70 to 0.89). No statistically significant difference was shown for disease free survival.No statistically significant difference was shown for any other comparison.

AUTHORS' CONCLUSIONS

Altered fractionation radiotherapy is associated with an improvement in overall survival and locoregional control in patients with oral cavity and oropharyngeal cancers. More accurate methods of reporting adverse events are needed in order to truly assess the clinical performance of different radiotherapy regimens.

Phase I study of anti--epidermal growth factor receptor antibody cetuximab in combination with radiation therapy in patients with advanced head and neck cancer

PURPOSE

To evaluate the safety, pharmacokinetics, and efficacy of a chimeric anti-epidermal growth factor receptor monoclonal antibody, cetuximab, in combination with radiation therapy (RT) in patients with advanced squamous cell carcinoma of the head and neck.

PATIENTS AND METHODS

We treated 16 patients in five successive treatment schedules. A standard dose escalation procedure was used; three patients entered onto the study at each dose level of cetuximab received conventional RT (70 Gy, 2 Gy/d), and the final three patients received hyperfractionated RT (76.8 Gy, 1.2 Gy bid). Cetuximab was delivered as a loading dose of 100 to 500 mg/m(2), followed by weekly infusions of 100 to 250 mg/m(2) for 7 to 8 weeks. Circulating levels of cetuximab during therapy were determined using a biomolecular interaction analysis core instrument. Human antichimeric antibody response was evaluated with a double-antigen radiometric assay. The recommended phase II/III dose was defined as the optimal cetuximab dose level based on the pharmacologic parameters and adverse events.

RESULTS

The most commonly reported adverse events were fever, asthenia, transaminase elevation, nausea, and skin toxicities (grade 1 to 2 in most patients). Skin toxicity outside of the RT field was not strictly dose-dependent; however, grade 2 or higher events were observed in patients treated with higher dose regimens. There was one grade 4 allergic reaction. Most acute adverse effects were associated with RT (xerostomia, mucositis, and local skin toxicity). No antibodies against cetuximab were detected. All patients achieved an objective response (13 complete and two partial remissions).

CONCLUSION

Cetuximab can be safely administered with RT. The recommended dose for phase II/III studies is a loading dose of 400 to 500 mg/m(2) and a maintenance weekly dose of 250 mg/m(2).

Determination of tumor kinetics: strategies for the delivery of radiotherapy and chemotherapy

Both clinical and laboratory evidence indicates that local control rates for many experimental and clinical human tumors decrease with protraction of the overall duration of radiation therapy and that a likely basis for this decrease is tumor cell repopulation during treatment. Such observations have stimulated interest in tumor kinetics, and a number of techniques have been developed that increase the potential for meaningful clinical study of the proliferative behavior of tumors. This review discusses the clinical and experimental evidence for proliferation during treatment, describes two potential approaches-accelerated fractionation and concurrent chemotherapy and radiotherapy-that can be employed to counteract such intratreatment proliferation, explores methods available for measuring tumor cell kinetics, and discusses how kinetics information may be used in the future to tailor therapy to a tumor's individual characteristics.

Early closure of a randomized trial: surgery and postoperative radiotherapy versus radiotherapy in the management of intra-oral tumours

Tumours of the oral cavity/oropharynx occur relatively infrequently in the UK. The management of such lesions, especially the squamous cell carcinomas, is still a little controversial. Some centres advocate radiotherapy while others adopt surgery and radiotherapy. In an attempt to resolve the question of which approach gives the better results, a multicentre randomized trial was established to compare surgery plus postoperative radiotherapy with radical radiotherapy alone. It was anticipated that 350 patients would be required to give a statistically significant result, but, after 35 patients had been entered, the trial was closed prematurely with a marked difference in overall survival in favour of the combination arm (P = 0.0006). At this analysis, carried out 23 months after trial closure, the survival difference between the two arms remains statistically significant for all causes of mortality (P = 0.001; relative death rate = 0.24; 95% CI 0.10-0.59).

Neoadjuvant chemotherapy and hyperfractionated radiotherapy with concurrent low-dose chemotherapy for squamous cell esophageal carcinoma

PURPOSE

We conducted a prospective study of neoadjuvant treatment for squamous cell carcinoma of the esophagus, modifying the chemotherapy protocol by adding l-folinic acid and giving bifractionated radiotherapy with a cis-diaminedichloroplatinum (CDDP) injection before each fraction.

METHODS AND MATERIALS

Thirty-two patients, 30 men, 2 women, mean age 56.2+/-8.9 years, with resectable squamous cell carcinoma of the esophagus (TNM stage I=4, IIA=4, IIB=13, III=11) were included. Chemotherapy, CDDP (80 mg/m2 D2), 5-fluorouracil (5-FU; 600 mg/m2, D1-4), and l-folinic acid (200 mg/m2, D1-4), was given in two sessions with a 3-week interval during which the patients received radiotherapy (45 Gy), two fractions per day (150 cGy/fraction). A 3-mg injection of CDDP was given prior to each fraction. Patients underwent surgery 4 to 7 weeks after neoadjuvant therapy.

RESULTS

No severe side effects were observed in 12 patients. Grade 3 effects (WBC, platelets, mucositis) occurred in 16 patients and grade 4 effects (platelets, mucositis) in four including 1 death due to septicemia with an infected catheter. Surgery was performed in 29 patients; 26 had resectable tumors (81%). Operative mortality was 10%. The 26 surgical specimens showed complete response (n=18), persistent microscopic residues (n=4), or not significant modification (n=4). Survival at 1, 2, and 3 years was 81, 61, and 51.6% and disease-free survival was 75, 59, and 54% respectively.

CONCLUSIONS

This new therapeutic combination is aggressive and associated with a high postoperative mortality but has a remarkable histological effect since complete response was achieved in 56% (95% CI: 39-73%) of the patients and 3-year survival reached 52%, a very high rate in our experience.

Hyperfractionated radiation in combination with local hyperthermia in the treatment of advanced squamous cell carcinoma of the head and neck: a phase I-II study

Twenty-seven patients with cervical metastases from squamous cell head and neck tumours were treated with hyperfractionated XRT (total dose 69.60-76.80 Gy, 1.2 Gy b.i.d. five times a week) combined with a total of two to six sessions of superficial external HT. Acute local toxicity was mild; as major acute side effects, only one ulceration was recorded. No severe late side effects were observed. Late toxicity was similar to that observed in our previous studies with the combination of heat and radiation. Nodal complete response was observed in 77% of patients, partial response was observed in 15% of patients and no change was observed in 8% of patients. Five-year actuarial nodal control was 64.5 +/- 19% and 5-year actuarial survival was 24 +/- 10%. The treatment of nodal metastases from head and neck tumours with the combination of HT and hyperfractionated XRT is feasible with an acceptable acute and late toxicity profile.

A randomised trial of accelerated versus conventional radiotherapy in head and neck cancer

BACKGROUND AND PURPOSE

To study the effect of accelerated radiation treatment in locally advanced head and neck cancer, a prospective randomised trial was conducted comparing two fractionation schemes which differed only in the overall treatment time; fraction size and total dose were the same in both arms.

MATERIALS AND METHODS

Eighty-two patients with stage 3 or 4 squamous cell cancer of the oral cavity, oropharynx, hypopharynx or larynx considered suitable for radical radiotherapy as primary treatment were stratified by site and stage and randomised to receive 66 Gy in 33 2 Gy daily fractions in 45-48 days (o.d.) or 66 Gy in 33 2 Gy twice daily fractions in 22-25 days (b.i.d.).

RESULTS

An initial improved clinical response in tumour control in the b.i.d. arm was not sustained and the 3 year recurrence free survival and overall survival rates were similar and not significantly different. The actuarial recurrence free survival was 49.1% in the b.i.d. arm and 44.3% in the o.d. arm. The disease free 3 year survival was 59.4% and 56.8%, respectively. The acute and late normal tissue effects were scored using the RTOG scale. As expected the acute effects were much greater in the b.i.d. arm. The combined grade 3 and 4 late effects were similar but the proportion of grade 4 reactions was significantly higher in the b.i.d. arm. The increase in grade 4 toxicity caused the trial to be discontinued after 82 of the planned 226 patients had been randomised.

CONCLUSIONS

The severity of the normal tissue effects and a failure to demonstrate sustained local control does not support this fractionation scheme in patients with such extensive head and neck cancer.

Hyperfractionation: where do we stand?

Hyperfractionation is generally expected to allow an escalation of total dose, thereby increasing tumour control rate, without increasing the risk of late complications. The purpose of this review is to assess the empirical evidence for this therapeutic gain from hyperfractionated radiotherapy. Although extensive clinical data have been accumulated until now, especially on treatment of head and neck cancer, the line of evidence is not consistent. The present analysis indicates that the dose per fraction generally used in standard radiotherapy is already a good choice.

Partially hyperfractionated accelerated radiotherapy and concurrent chemotherapy for advanced nasopharyngeal carcinoma

PURPOSE

A newly designed concomitant chemoradiotherapy was undertaken to assess the feasibility and efficacy for advanced nasopharyngeal carcinoma (NPC).

METHODS AND MATERIALS

Sixty-three patients with biopsy-proven NPC were entered in this Phase II trial from March 1992 to November 1993. Most patients present with Stage IV disease (93.4%) and poorly differentiated epidermoid carcinoma or undifferentiated carcinoma were the major pathologic type. Radiotherapy was delivered using a telecobalt unit and 10 MV x-rays and by altered fractionation (72-74 Gy/45 fractions/6 weeks). Chemotherapy with cisplatin 75 mg/m2, 2 h infusion at day 1, followed by 5-FU 400 mg/m2/day, continously infused for 4 days was given concurrently during the first and fifth weeks of radiotherapy.

RESULTS

The major toxicity was mucositis (61% belong to Grade 3, 31% to Grade 2). Weight loss, leucopenia, and skin reaction were frequently encountered. Three patients withdrew from treatment at 15, 25, and 55.5 Gy, three patients interrupted the radiotherapy for 1-4.5 weeks, and two patients refused the second cycle of concomitant chemotherapy due to toxicities. The initial tumor response showed 100% overall response rate, with 90.5% complete response. After a median follow-up time of 38 months, five patients failed at the primary and/or neck (four recurrent and one persistent), and 14 patients developed distant metastases alone. The 3-year primary disease-free, regional disease-free, distant disease-free, and overall survival rates are 89.1, 92.8, 74.3, and 73.6%, respectively. The late complication rate is acceptable so far.

CONCLUSIONS

Our data indicates that concurrent chemoradiotherapy for advanced NPC is both feasible and effective, with acceptable toxicities. Distant metastases are the major site of treatment failure. Postradiation adjuvant chemotherapy to eradicate subclinical distant metastasis should be further studied.

Differential effects of retinoic acid and N-(4-hydroxyphenyl)retinamide on head and neck squamous cell carcinoma cells

Both retinoic acid (RA) and the synthetic retinoid N-(4-hydroxyphenyl)retinamide (4HPR) have shown efficacy in head and neck cancer chemoprevention trials. To compare their activity and mechanism of action, the 1483 oral head and neck squamous cell carcinoma (HNSCC) cell line was grown in organotypic culture, an in vitro system that allows cellular stratification and simulates carcinoma in situ, and was exposed to 10 micromol/L of either RA or 4HPR. Extensive apoptosis, as evidenced by in situ deoxyribonucleic acid end-labeling, occurred in 4HPR-treated cultures after 9 days, with >80% cell loss (P< .001). In contrast, the growth of cultures treated with RA was inhibited by only 32%, with no evidence of apoptosis. Because 4HPR has low systemic toxicity and is a potent inducer of apoptosis in HNSCC cells, its role in chemoprevention of head and neck cancers, including cancers that are resistant to RA-induction therapy, warrants further investigation.

Potential doubling time and clinical outcome in head and neck squamous cell carcinoma treated with 70 GY in 7 weeks

PURPOSE

To study the predictive value of pretreatment potential doubling time and labeling index, as measured by flow cytometry in patients with head and neck squamous cell carcinoma treated with conventional radiotherapy.

METHODS AND MATERIALS

70 patients with a squamous cell carcinoma of the oropharynx and 4 patients with another involved head and neck site were entered in this prospective study. The duration of the S phase (TS), the labeling index (LI), and the potential doubling time (Tpot) were obtained by flow cytometry measurements of a tumor biopsy obtained after i.v. injection of 200 mg bromodeoxyuridine to the patient. The treatment consisted of 70 Gy in 7 weeks, 2 Gy per fraction and five fractions per week.

RESULTS

The mean and median LI were 7.7% (standard deviation, SD: 5.0) and 6.3%, respectively. The mean and median TS were 9.3 h (SD: 3.6) and 8.3 h, respectively. The mean and median Tpot were 5.6 days (SD: 5.4) and 4.6 days, respectively. No significant relationship was found between the Tpot or LI and the tumor stage (T), nodal status (N), histological grade, and the site of the primary within the oropharynx. The only parameter significantly associated with an increased risk of local relapse was the tumor stage (p < 0.001). The mean Tpot for the group of tumors that relapsed locally was 5.3 days (SD: 3.3), compared to 6.1 days (SD: 4.08) for those who did not relapse locally (NS). Two parameters were significantly associated with a decrease in disease-free (DFS) and overall survival, namely the tumor stage (p < 0.005, and p < 0.001, respectively, for DFS and overall survival) and nodal involvement (p = 0.02 and (p < 0.005, respectively, for DFS and overall survival). The TS, LI, DNA index, and Tpot were not significantly associated with local relapse, DFS, and survival, either in the univariate or in the multivariate analysis.

CONCLUSIONS

The method used to evaluate tumor cell kinetics did not provide clinically relevant kinetic parameters for this type of cancer. The classic prognostic factors (tumor stage and nodal status) were strongly associated with clinical outcome.

Carbogen and nicotinamide as radiosensitizers in a murine mammary carcinoma using conventional and accelerated radiotherapy

PURPOSE

To compare the radiosensitivity of mouse tumors treated in air with conventional and accelerated radiotherapy with that of tumors treated in carbogen alone or carbogen combined with nicotinamide.

METHODS AND MATERIALS

CaNT mammary tumors were irradiated with either 30 x-ray fractions in 6 weeks or 40 fractions in 26 days in air, carbogen alone, or carbogen combined with 120 mg/kg of nicotinamide (NAM), the latter given intraperitonealy 30 min before each fraction. The response to treatment was assessed using local control, weight loss, and metastasis-free survival.

RESULTS

Both carbogen and carbogen plus nicotinamide significantly increased tumor radiosensitivity; enhancement ratios (ERs) in the 6-week regimen were similar to those seen in the accelerated schedule. The majority of the effect was achieved by carbogen alone but the addition of NAM further enhanced tumor radiosensitization (ERs of 1.5 and 1.4 for carbogen in the conventional and accelerated schedule, respectively, were significantly lower than ERs of 1.7 and 1.6 obtained with carbogen plus nicotinamide; p < or = 0.005). Treatment protraction significantly increased radioresistance, especially when tumors were treated under air. An extra 1.5 Gy per day was required in air to counterbalance proliferation; in carbogen alone and carbogen plus nicotinamide a dose loss of 0.9 and 0.6 Gy per day was observed, respectively. Compared with treatments in air alone delivered in 6 weeks, acceleration of treatment combined with carbogen and nicotinamide gave the greatest increase in tumor radiosensitization (ER = 1.9). No toxic side effects and no detrimental changes in body weight were encountered when the sensitizers were administered 30 times (one fraction per day) or 40 times (two fractions per day). In both regimens, the incidence of metastases in mice treated with carbogen or carbogen plus nicotinamide was similar to that seen in animals treated in air. There was, however, a nonsignificant trend of a higher proportion of mice with metastasis in the accelerated schedule compared with the 6-week schedule.

CONCLUSIONS

In both conventional and accelerated experimental radiotherapy, carbogen alone or combined with a small clinically relevant dose of NAM were well tolerated, achieved large and significant increases in radiosensitization, and did not affect the incidence of metastases. The sparing of damage, resulting from extending the overall treatment time, was less when the sensitizers were administered than when irradiations were performed in air. The study suggests that clinical radiotherapy regimens, which aim to reduce hypoxic and/or tumor clonogen proliferation, would benefit from the use of carbogen, especially if the gas is combined with nicotinamide and treatment acceleration.

The EORTC randomized trial on three fractions per day and misonidazole in advanced head and neck cancer: prognostic factors

In trial no. 22811 on a randomized comparison of multiple fractions per day (MFD), with or without misonidazole, to conventional fractionation in advanced head and neck cancer, a large number (523) of patients was entered in a short period of time. No differences in treatment results were obtained, but the study created an important database, allowing for detailed evaluation of the most important factors influencing prognosis. In univariate analysis, factors significantly influencing survival and locoregional control were: performance status, histological differentiation, tumor site, tumor and nodal staging, and tumoral and nodal volume. In multivariate analysis, significant factors for survival were nodal involvement, tumor stage, performance status, and tumor site. Significant factors for locoregional control were nodal involvement and total tumor burden. This analysis suggests that total tumor burden (volume) should be included in the interpretation of treatment results in head and neck cancer.

Influence of tumoral, radiobiological, and general factors on local control and survival of a series of 361 tumors of the velotonsillar area treated by exclusive irradiation (external beam irradiation+brachytherapy or brachytherapy alone)

PURPOSE

To evaluate statistically the factors influencing the therapeutic results.

METHODS AND MATERIALS

A statistical study was carried out concerning 361 patients treated from 1977 to 1991 for velotonsillar carcinoma. They received either brachytherapy alone (18) or a combination of external beam irradiation and brachytherapy (343 patients) using an afterloading iridium technique in plastic tubes. The distribution of patients according to the localization was: 128 tonsils, 134 soft palates, 9 posterior pillars, 63 anterior pillars, and 27 glossotonsillar sulcus. The patients were staged as follows: 90 T1, 141 T2, 119 T3, 2 T4, 9 Tx with 230 N0, 93 N1, 9 N2, 20 N3, and 9 Nx.

RESULTS

The results at 5 and 10 years show: local control 80% and 74%, locoregional control 75% and 70%, overall survival 53% and 27%, specific survival 63% and 52%, respectively. The univariate study shows at 5 years a better local control for T1T2 (87%) compared with T3 (67%) with p = 0.00004. The locoregional control is better for N0 (80%) than for N+ (55%) with p = 0.002. This is the same for the overall survival (59% vs. 42%, p = 0.002). Tumors with an extension to the mobile tongue or the base have a poor prognosis (p < 0.002). The radiobiological factors show less recurrences if the total duration of the treatment is < 55 days, the number of days between External Beam Irradiation and brachytherapy is < 20. The security margin seems important also.

CONCLUSIONS

For the combination external irradiation and brachytherapy, the multivariate study for local control shows that ony T, localization, and the total duration of treatment are significant. For complications, classified into four grades, only the dose rate is significant.

Cancer of the head and neck

Cancers of the upper aerodigestive tract, collectively known as head and neck cancers, arise from a multiplicity of sites. In the West, excess tobacco and alcohol consumption are the most important of the known predisposing factors; elsewhere in the world, notably in India and China, the aetiology, pattern of primary sites, and clinical behaviour are different. Clinically these tumours pose exceptional problems in management, and skilled multidisciplinary teams are necessary in order to achieve the highest level of service and research. Historically, surgery and radiotherapy have been the most important treatment modalities; chemotherapy is now increasingly employed but not yet fully established. Successful rehabilitation of patients with head and neck cancers requires access to high quality speech therapists and other support staff with training in functional pharyngeal disorders. Current research efforts are largely directed towards defining the proper role of chemotherapy and assessing the possible advantage of unconventional radiation approaches. In recent years the roles of primary, reconstructive, and salvage surgery have also become better defined. Many patients are suitable for randomisation into ongoing prospective clinical trials which have been specifically designed to address these issues.

Iridium-192 interstitial implant and external beam radiation therapy in the management of squamous cell carcinomas of the tonsil and soft palate

PURPOSE

To evaluate the results, techniques, indications and complications of interstitial brachytherapy in the management of squamous cell carcinomas of the tonsil and soft palate, we reviewed the Stanford University Medical School experience with this modality.

METHODS AND MATERIALS

Between May 1975 and January 1990, 37 patients with squamous cell carcinomas of the Tonsillo-Palatine region were treated with a combination of external beam irradiation and a removable Iridium-192 interstitial implant. The mean age of these patients was 56. Twenty-two were males and 15 were females. The stage distribution included four patients with Stage I, 5 with Stage II, 10 with Stage III, and 18 with Stage IV cancers. Thirty-two percent (12/37) of these patients had T3 or T4 lesions. Forty-nine percent (18/37) had stage N2 or N3 cervical lymphadenopathy. All 37 patients received initial external beam irradiation to the primary, bilateral necks, and supraclavicular region (mean dose: 5400 cGy, range 4000-6600). Eighteen patients (49%) also received neck dissections. All 37 patients received an interstitial Irridium-192 implant using a combination intraoral swage and external looping technique. The mean dose was 2700 cGy (range 2000-4000 cGy) to an average volume of 24 cc (range 5-81).

RESULTS

Local control was obtained in 95% (35/37) of the patients. Eighty-seven percent (32/37) of the patients have remained disease-free in the neck. Nine patients have developed second primary lesions, and one developed pulmonary metastasis. Fifteen patients have died (6 succumbed to their cancers, 6 to second primaries, 2 to intercurrent disease, 1 from an unknown cause). The actuarial freedom from relapse is 75%, and overall survival is 64% at 5 years, with a mean follow up of 43 months (range 5-110). Complications were limited to one case of osteoradionecrosis of the mandible and one tonsillar ulcer. Functional and esthetic integrity was preserved in most of these patients.

CONCLUSION

Iridium-192 interstitial implant boost combined with external beam radiation therapy is a safe and effective therapy in the management of locally advanced carcinomas of the tonsil and soft palate.

High dose external beam radiation therapy with or without concomitant chemotherapy for esophageal carcinoma

Esophageal cancer patients treated with radiotherapy (RTx) are most often those with malignancies too extensive for surgery or those who deemed medically unsuitable for an aggressive surgical approach. Summarizing RTx series, the 2-year survival rate is in the range of 10% and at 5 years about 5%. Although not randomly compared, these results are not significantly worse than those achieved with surgery in more advanced tumors. In stage I/II tumors, more recent trials reported of 5-year survival rates varying between 12% and 20%. These data indicate that irradiation may be administered with curative intention but usually only for patients who are also candidates for primary surgery. On the other hand, modern RTx (doses > 60 Gy) +/- endoluminal after-loading may provide good palliation (relief of dysphagia) for patients with good prognostic factors such as weight loss of less than 10% body weight, good performance status, younger age, and location of the tumor. In the perioperative setting, RTx reduced the frequency of the local recurrences but did not increase the overall resection and R0 resection rates and did not improve survival due to more patients relapsing at distant sites. Combined chemoradiotherapy has shown to be superior to RTx alone with respect to local control, disease free survival and overall survival and in a marked reduction of distant failures. These data support the use of chemoradiotherapy as standard treatment of locally advanced and nonresectable esophageal cancer. They also provide a basis for randomized trials comparing chemoradiotherapy alone versus preoperative treatment modalities.

A phase I/II trial of twice daily irradiation and concurrent chemotherapy for locally advanced squamous cell carcinoma of the head and neck

PURPOSE

This study was designed to test the toxicity and efficacy of a regimen of twice daily irradiation and concurrent multiagent chemotherapy for patients with locally advanced squamous cell carcinoma of the head and neck.

METHODS AND MATERIALS

This was a prospective Phase I/II trial. Patients received 125 cGy b.i.d. to 7000 cGy with a 6 hr interfraction interval. Chemotherapy was given during weeks 1 and 6 of irradiation and consisted of a 5 day infusion of 5-fluorouracil at 600 mg/M2/day and 5 daily injections of cisplatin at 12 mg/M2/day. Two additional cycles of chemotherapy were given after the completion of radiotherapy.

RESULTS

Forty-six patients were evaluable: 28 had technically unresectable disease and 18 had resectable tumors. All had Stage III or IV disease: 84% had T3 or T4 primaries while 53% had > or = N2 neck disease. The primary acute toxicity, confluent mucositis, was seen in 74% of patients. Late side effects occurred in four patients. Median follow-up is 36 months (range 25-44 months). Kaplan-Meier estimates of 2-year disease-free survival and overall survival are 65% and 73%, respectively, while 2-year local regional control and distant disease-free survival are 72% and 88%, respectively. Multivariate analysis revealed that resectability and receiving > 2 cycles of chemotherapy significantly influenced local regional control while age < 60 significantly influenced disease-free survival.

CONCLUSION

This form of treatment can be delivered safely. The encouraging results have led to the initiation of a Phase III trial comparing this regimen with b.i.d. radiation alone.

Radiation injuries of the colon and rectum

Approximately 5% to 10% of patients receiving abdominopelvic radiation therapy will develop a colon or rectal injury. Thorough evaluation of the patient to determine the extent of the injury and the presence of concomitant lesions and to rule out recurrent malignancy is urged. Many radiation complications can be managed with medical regimens. Although colostomy remains a valuable and frequently utilized mode of treatment, it is by no means the sole alternative when surgical intervention is required. Rectal resection with colorectal or coloanal anastomosis can be performed safely for some injuries involving the distal rectum. Surgery for irradiated bowel should be focused on minimizing dissection to minimize injuries and on providing healthy non-irradiated tissues to provide adequate blood supply to promote healing. Patients who have received abdominopelvic radiation are at greater risk of developing colorectal cancer, and cancer surveillance should be commenced 5 years after completion of therapy.

Primary site management following induction chemotherapy with cis-platinum, 5-fluorouracil, and leucovorin

A phase II clinical trial was initiated in 1987 to evaluate a new induction regimen of cis-platinum, 5-fluorouracil, and leucovorin (PFL) for patients with stages III-IV squamous cell carcinoma of the head and neck. Ninety patients were treated and followed for a median duration of 18 months. The median age was 55 and 87% of the patients had stage IV disease. The rates of complete and overall clinical response following three cycles of PFL were 57% and 80%, respectively; the rate of complete response at the primary site was 72%. Eighty-four percent of patients were treated to the primary site with radiation alone (median dose 68 Gy in daily 1.8-Gy fractions) irrespective of the location of the primary site or initial T-stage. The acute tolerance to full-course radiation following PFL was acceptable. The actuarial rate of primary site control for patients treated with radiation was 67% at 36 months. An important prognostic indicator for primary site control was a complete clinical response to induction PFL. For patients who achieved a complete response, radiation or surgery followed by radiation controlled primary site disease equally well at 70%. Patients with a partial response did less well. For these patients, surgery and radiation appeared slightly better than radiation alone.

Regaud Lecture, Malmö, 1992. The clinical science of radiation oncology

Claudius Regaud can be regarded as the founding father of both radiobiology and radiotherapy. His research extended widely in oncology and the conclusions which he drew from his work are considered in the light of our modern practice of the clinical science of radiation therapy.

In vivo measurement of the potential doubling time by flowcytometry in oropharyngeal cancer treated by conventional radiotherapy

PURPOSE

Experimental and clinical studies suggest that the pre-treatment potential doubling time could be predictive of tumor control in patients treated by conventional radiotherapy and could help to identify the rapidly growing tumors for which accelerated radiotherapy is required.

METHODS AND MATERIALS

To test this hypothesis, we studied prospectively 48 patients with a squamous cell carcinoma of the oropharynx and treated by conventional radiotherapy (70 Gy/7 weeks). The duration of S phase, the labeling index and the potential doubling time were obtained by flowcytometry measurements of a tumor biopsy obtained after injection of 200 mg bromodeoxyuridine to the patient.

RESULTS

Three parameters were significantly associated with an increased risk of relapse namely the tumors size (T4; p < 0.01), the nodal status (> or = N2; p < 0.05) and the site of the primary within the oropharynx (p = 0.08). The S phase, labeling index, DNA index and potential doubling time were not significantly associated with an increased risk of relapse. However when considering only the T2 subgroup of patients, high labeling indexes and short potential doubling time were associated with an increased risk of relapse: the mean pre-treatment potential doubling time of the tumors which relapsed was 3.21 versus 5.5 days when there was no evidence of local relapse (p < 0.05). The mean labeling index for the group of tumors associated with a tumor recurrence was 11.7% compared to 7.3% when there was no evidence of relapse (p = 0.02).

CONCLUSION

Factors other than proliferation play a role in determining the outcome of oropharyngeal cancers treated by conventional radiotherapy. However there was a significant correlation between short potential doubling time, high labeling index and tumor recurrence in the T2 subgroup of patients. The finding of significance for potential doubling time and labeling index in the T2 subset of tumors may be a reflexion of the more homogeneous nature of these tumors with regard to prognostic variables.

Pilot study of accelerated hyperfractionated thoracic radiation therapy in patients with unresectable stage III non-small cell lung carcinoma

BACKGROUND

The primary goal of this study was to determine the incidence of severe or greater acute radiation toxicity, and secondarily, response, survival, and local control in patients with unresectable Stage IIIA or B non-small cell lung cancer treated with accelerated hyperfractionated thoracic radiation therapy (AHTRT).

METHODS

From September, 1989 through March, 1990, 21 evaluable patients with unresectable Stage IIIA or B non-small cell lung cancer were treated with AHTRT, using 6000 cGy in 40 fractions of 150 cGy twice daily, 6 hours between fractions, with a 2-week break midway through treatment.

RESULTS

Two patients (9.5%) had acute Grade 3 radiation esophagitis requiring intravenous hydration, and two patients (9.5%) had acute Grade 3 radiation pneumonitis requiring oxygen and steroids. Only one patient had chronic toxicity, a Grade 3 radiation pneumonitis. Five patients (24%) achieved a complete response, whereas eight (38%) had a partial response or regression. With minimum follow-up of nearly 3 years, 3 patients are alive and 18 are dead. The median survival time and 1-, 2-, and 3-year survival rates were 10.8 months, 48%, 29%, and 14%, respectively. Local control was achieved in 11 of 21 (52%) patients.

CONCLUSIONS

This AHTRT regimen can be given with an acceptable incidence of acute radiation toxicity. Response, survival, and local control rates in this unfavorable group of patients are encouraging. A North Central Cancer Treatment Group Phase III study of standard thoracic radiation therapy (6000 cGy in 30 fractions of 200 cGy daily) versus AHTRT (+/- chemotherapy) is now open.

Radiotherapy of tonsillar and base of the tongue carcinoma. Prediction of local control

119 patients with squamous cell carcinoma of the tonsillar region (68) and the base of the tongue (51), who received external radiotherapy with curative intent between 1966 and 1984, are analysed with respect to overall treatment results, local tumour control and prognostic factors. Radiation doses were equivalent to 60-70 Gy in 6-7 weeks, with a mean fraction dose of 2.4 Gy on the cobalt 60 equipment and 2 Gy on the linear accelerator. Significant differences were found between both oropharyngeal subsites. Three-year overall survival was 57% in tonsillar carcinoma and 38% in base of the tongue (P = 0.006); disease-specific survival was 70% and 47%, respectively (P = 0.005); and local control rates were 82% and 61% (P = 0.02). Late damage to normal tissues, like persistent dysphagia and osteomyelitis, were seen in 11% of patients. Patients with large tumours in the tongue based developed significantly more complications (P = 0.04). T-stage and tumour subsite predicted local control independently before start of the treatment (P = 0.02 in both cases). A significant nonlinear correlation between Normalised Total Dose (using an alpha/beta ratio of 15 Gy) and local control rate was found (P = 0.006), the middle range having the worst prognosis. The size of radiation field and overall treatment time did not correlate with local control in either site. Response at the end of radiotherapy and 6 weeks later have additional prognostic value for local control, irrespective of the initial stage or subsite (P = 0.004 and < 0.001, respectively).

Evolving role of surgery after induction chemotherapy and primary site radiation in head and neck cancer

Chemotherapy, as preliminary treatment before surgery and/or radiation for advanced squamous cell carcinoma of the head and neck, is no longer novel. In prospective trials to date, however, multiple agent induction chemotherapy has yet to demonstrate the initial presumptive promise of improved rates of cure. As an alternate goal, there has emerged a renewed attentiveness toward limiting treatment morbidity, several strategies for which may be considered. Extirpative, often radical, surgery on the primary site of disease usually represents the most significant threat to life quality. Various ways of limiting surgical morbidity will be considered by way of introduction. The trends of head and neck cancer treatment over the decades, leading into the era of induction chemotherapy and refined radiation techniques, will be described. At the combined Dana-Farber/New England Deaconess Head and Neck Oncology Clinic, an experience with over 300 patients receiving induction chemotherapy for advanced head and neck cancer has been analyzed with an emphasis on the postulate of lessening the extent of surgery in appropriately selected patients. In a comparison between trials initiated in 1980 and 1987, improved complete response rates from 26 to 57% were documented. Survival rates were identical, but the use of planned primary site ablative surgery was decreased from 47 to 14%. While some increase in local failure has been noted in patients treated by primary site radiation alone, surgical salvage appeared to be more effective. The implication of these trends for patterns of failure and surgical salvage and data concerning the need for neck dissection in this group of patients will be briefly summarized. Other trials addressing organ-preservation strategies will also be referenced and the dichotomy between survival-based studies and morbidity-limiting studies illustrated. Independent trends in radiation technique as a potential substitute for traditional surgical practice will be reviewed.

Hyperfractionation versus conventional fractionation in oropharyngeal carcinoma: final analysis of a randomized trial of the EORTC cooperative group of radiotherapy

EORTC protocol 22791 compared once daily fractionation (CF) of 70 Gy in 35-40 fractions in 7-8 weeks, to pure hyperfractionation (HF) of 80.5 Gy in 70 fractions in 7 weeks using 2 fractions of 1.15 Gy per day, in T2-T3 oropharyngeal carcinoma (excluding base of tongue), N0,N1 of less than 3 cm. From 1980 to 1987, 356 patients were entered. In the final analysis (June 1990), the local control was significantly higher (p = 0.02 log-rank) after HF compared with CF. At 5 years, 59% of patients are local disease-free in the HF arm compared to 40% in the CF arm. The superiority of HF was demonstrated in patients staged T3N0,T3N1 but not in T2. The Cox model confirmed that the treatment regimen was an independent significant prognostic factor for locoregional control (p = 0.007 log-rank). This improvement of locoregional control was responsible for a trend to an improved survival (p = 0.08 log-rank). There was no difference in late normal tissue damage between the two treatment modalities.

The 1991 Elis Berven Lecture. Radiotherapy in the nineties. Increase in cure, decrease in morbidity

Advance in radiotherapy can be achieved by obtaining a greater tumour control and by reducing the morbidity of treatment, both early and late. The factors influencing both means of benefiting the cancer patient are considered.

Velotonsillar squamous cell carcinoma: 277 cases treated by combined external irradiation and brachytherapy--results according to extension, localization, and dose rate

From 1977 to 1987, 277 patients with velotonsillar cancer (oropharyngeal cancer excluding base of tongue and valleculae) were treated by brachytherapy either alone (14 patients) or combined with external beam irradiation (263 patients) using a new afterloading Iridium-192 technique. The distribution of patients according to the localisation was as follows: 106 tonsillar region, 98 soft palate, 45 anterior pillar, 8 posterior pillar and 20 pharyngoglossal sulcus. According to the UICC TNM classification of 1979, the patients were staged as follows: 65 T1, 103 T2, 101 T3, 8 TX. 172 patients were NO, 74 N1, 3 N2, 20 N3 et 8 NX. According to the tumor extension, the 5 year actuarial local control, locoregional control, specific survival and overall survival by T stage (T1 [65 pts], T2 [103 pts.], T3 [101 pts]) were respectively: local control: 89%, 86%, 69%; locoregional control: 84%, 80%, 67%; specific survival (excluding patients dead with intercurrent disease or second cancer): 78%, 62%, 46%; overall survival: 62%, 53%, 43%. No local recurrence was detected after 3 years. According to the localization, the tumors arising from the tonsillar region, the soft palate and the posterior pillars (A Group) had a better prognosis than the tumors arising from the anterior pillars and glossotonsillar sulcus (B Group). The complications were classified into four grades according to their extension and duration: Grade 1 (minor) with very small tissue ulcer which healed within 2 months with medical treatment (20%). Grade 2 (moderate) (5%), grade 3 (severe) (1.4%), grade 4 (fatal) (0.4%). The dose rate seemed to be relatively higher in patients with grade 2 and 3 complications (70 cGy per hour on average) versus the dose rate of patients without complications (50 cGy per hour) but the difference was not significant. In conclusion, the brachytherapy boost after external irradiation can be performed under favourable conditions with an acceptable rate of complications. It was set out in order to attempt to improve the local control of the tumor while preserving the salivary function and lessening the muscular fibrosis. It shows how experienced the team is, however only a randomized study would allow to state whether this technique brings about a real improvement especially as for tumors T2 or T3.