Iridium-192 brachytherapy in the management of 147 T2N0 oral tongue carcinomas treated with irradiation alone: comparison of two treatment techniques

Brachytherapy of the head and neck: An University of California Los Angeles guide to morbidity reduction

The head and neck (H&N) region is among the most intricate and functional part of our anatomy. Major functional nerves and blood vessels with importance that affect the entire body emanate from the base of skull. Brachytherapy plays an important role as a single modality therapy in early cancer of the lip and oral cavity and a supplemental role in the pharynx or in advanced or recurrent disease. Morbidity in the H&N is intensely personal and disabling. Its avoidance is critical in determining the success or failure of a treatment program, and it is essential to preservation of quality of life. This article summarizes the current literature regarding morbidity related to H&N brachytherapy to aid patients and physicians to achieve optimal outcomes.

Brachytherapy in head and neck malignancies: Indian Brachytherapy Society (IBS) recommendations and guidelines

PURPOSE

Brachytherapy (BT) forms major treatment modality in squamous cell carcinoma of head and neck cancers (HNC). However, there is a dearth of literature and guidelines for the use in various indications. High-dose-rate brachytherapy (HDR-BT) in Indian scenario is an important treatment modality, and the recommendations in this guidelines aim to provide the necessary recommendations for the use of HDR-BT for uniform application across the country in patients with HNC.

MATERIAL AND METHODS

A panel consisting of members of the Indian Brachytherapy Society (IBS), based on their clinical experience was invited. The process involved defining important steps, precautions, target volumes and indications, thorough literature review, and discussion with fellow members. The guidelines were established and formulated the recommendations for HDR-BT based on available evidences and individual experience for sites, relevant to Indian settings.

RESULTS

The IBS recommends the use of HDR brachytherapy as a part of treatment of head and neck tumors. The scope of these guidelines and recommendations included practical suggestions, ensuring efficient use of brachytherapy treatment as radical with external beam radiotherapy (EBRT) boost, palliative and adjuvant as definitive, or re-radiation as salvage for HNC in India. The IBS has made specific site-wise recommendations for previously untreated and recurrent HNC patients on their selection criteria, implant techniques, target volume definition, and HDR treatment parameters, such as time, dose rate, total dose, and fractionation schedules. Limited experience exists with HDR-BT in patients with head and neck cancers in India and across the globe.

CONCLUSIONS

IBS provided a consensus statement and guidelines for the head and neck brachytherapy and believed that these recommendations will overcome the fear of practicing radiation oncologists. This should generate interest amongst students and will help radiation oncologists all across the country to use the art of brachytherapy carefully in HNC patients, with better curative and salvage options.

Non-operative management for oral cavity carcinoma: Definitive radiation therapy as a potential alternative treatment approach

PURPOSE

To determine the outcomes of oral cavity squamous cell cancer (OSCC) patients treated with non-surgical approach i.e. definitive intensity-modulated radiation therapy (IMRT).

METHODS

All OSCC patients treated radically with IMRT (without primary surgery) between 2005-2014 were reviewed in a prospectively collected database. OSCC patients treated with definitive RT received concurrent chemotherapy except for early stage patients or those who declined or were unfit for chemotherapy. The 5-year local, and regional, distant control rates, disease-free, overall, and cancer-specific survival, and late toxicity were analyzed.

RESULTS

Among 1316 OSCC patients treated with curative-intent; 108 patients (8%) received non-operative management due to: medical inoperability (n = 14, 13%), surgical unresectability (n = 8, 7%), patient declined surgery (n = 15, 14%), attempted preservation of oral structure/function in view of required extensive surgery (n = 53, 49%) or extensive oropharyngeal involvement (n = 18, 17%). Sixty-eight (63%) were cT3-4, 38 (35%) were cN2-3, and 38 (35%) received concurrent chemotherapy. With a median follow-up of 52 months, the 5-year local, regional, distant control rate, disease-free, overall, and cancer-specific survival were 78%, 92%, 90%, 42%, 50%, and 76% respectively. Patients with cN2-3 had higher rate of 5-year distant metastasis (24% vs 3%, p = 0.001), with detrimental impact on DFS (p = 0.03) and OS (p < 0.02) on multivariable analysis. Grade ≥ 3 late toxicity was reported in 9% of patients (most common: grade 3 osteoradionecrosis in 6%).

CONCLUSIONS

Non-operative management of OSCC resulted in a meaningful rate of locoregional control, and could be an alternative curative approach when primary surgery would be declined, unsuitable or unacceptably delayed.

[Brachytherapy for head and neck cancers]

The main indications of the brachytherapy of head and neck cancers are the limited tumours of the lip, the nose, the oral cavity and the oropharynx. Nasopharynx tumours are nowadays treated by intensity-modulated radiotherapy. This technique can be exclusive, associated with external radiotherapy or postoperative. It can also be a salvage treatment for the second primaries in previously irradiated areas. If the low dose rate brachytherapy rules remain the reference, the pulse dose rate technique allows the prescription of the dose rate and the optimisation of the dose distribution. Results of high dose rate brachytherapy are now published. This paper reports the recommendations of the Gec-ESTRO, published in 2017, and takes into account the data of the historical low dose rate series, and is upgraded with the pulsed-dose rate and high dose rate series.

Edema worsens target coverage in high-dose-rate interstitial brachytherapy of mobile tongue cancer: a report of two cases

Purpose

We report our study on two patients to highlight the risk of underdosage of the clinical target volume (CTV) due to edema during high-dose-rate interstitial brachytherapy (HDR-ISBT) of mobile tongue cancer.

Material and methods

To treat the lateral side of the CTV, flexible applicator tubes were implanted on the mouth floor. Two-dimensional planning was performed using X-ray images for Case 1, and three-dimensional (3D) planning was performed using computed tomography (CT) for Case 2. Prescribed doses for both cases were 54 Gy in nine fractions.

Case reports

Case 1 was treated for cancer of the right lateral border of the tongue in 2005. Tongue edema occurred after implantation, and part of the lateral border of the tongue protruded between the applicator tubes. Acute mucosal reaction abated in the protruded area earlier than in the other parts of the CTV. In this case, the tumor recurred in this area 5 months after the treatment. Case 2 was treated for cancer of the left lateral border of the tongue. Because tongue edema occurred in this case also, plastic splints were inserted between the applicator tubes to push the edematous region into the irradiated area. The mucosal surface of the CTV was covered by the 70% isodose, and 100% isodose line for before and after splint insertion. Local control of the tumor was achieved 4 years after treatment.

Discussion and conclusions

To ensure sufficient target coverage, 3D image-based planning using CT should be performed, followed by re-planning using repeated CT as needed. Also, the development of devices to prevent protrusion of the edematous tissue outside the target area will help to ensure the full dosing of CTV.

American Brachytherapy Society Task Group Report: Combined external beam irradiation and interstitial brachytherapy for base of tongue tumors and other head and neck sites in the era of new technologies

Irradiation plays an important role in the treatment of cancers of the head and neck providing a high locoregional tumor control and preservation of organ functions. External beam irradiation (EBI) results in unnecessary radiation exposure of the surrounding normal tissues increasing the incidence of side effects (xerostomy, osteoradionecrosis, and so forth). Brachytherapy (BT) seems to be the best choice for dose escalation over a short treatment period and for minimizing radiation-related normal tissue damage due to the rapid dose falloff around the source. Low-dose-rate BT is being increasingly replaced by pulsed-dose-rate and high-dose-rate BT because the stepping source technology offers the advantage of optimizing dose distribution by varying dwell times. Pulsed-dose and high-dose rates appear to yield local control and complication rates equivalent to those of low-dose rate. BT may be applied alone; but in case of high risk of nodal metastases, it is used together with EBI. This review presents the results and the indications of combined BT and EBI in carcinoma of the base of tongue and other sites of the head and neck region, as well as the role BT plays among other-normal tissue protecting-modern radiotherapy modalities (intensity-modulated radiotherapy, stereotactic radiotherapy) applied in these localizations.

High-dose-rate interstitial brachytherapy for mobile tongue cancer: preliminary results of a dose reduction trial

Purpose

To compare the outcome of our facility with another about the shortened schedule (60 Gy in 10 fractions to 54 Gy in 9 fractions) of high-dose-rate interstitial brachytherapy (HDR ISBT) for mobile tongue cancer.

Material and methods

Eighteen patients were treated with HDR ISBT as a monotherapy in dose reduction schedule with some unique technique to determine the border of tumor accuracy (lugol's staining and metal marker), and to minimize adverse effect (lead-lined silicon block) at our facility.

Results

The 2-year local and regional control rates and cause-specific survival rate were 82%, 80%, and 83% and moderate to severe late complications occurred in five patients (28%), which were almost the same treatment results achieved by another facility.

Conclusions

We recommend 54 Gy in 9 fractions over 7 days as a feasible treatment to reduce patient discomfort in mobile tongue cancer patients.

Three-dimensional image-based high-dose-rate interstitial brachytherapy for mobile tongue cancer

To investigate the influence of a 3D image-based treatment-planning method for high-dose-rate interstitial brachytherapy (HDR-ISBT) for mobile tongue cancer, we analyzed dose-volume histogram results for the clinical target volume (CTV) and the mandible. Between October 2010 and November 2011, one and four patients having T2 and T3 tumors, respectively, were treated with HDR-ISBT. Multiplane implantation using 9-15 treatment applicators was performed. Lugol's iodine staining, metal markers, ultrasonography, and magnetic resonance imaging were used to identify the contours of the gross tumor volume (defined as the CTV). The results of the image-based treatment plan were compared with those of the conventional simulated plan on the basis of a reference point 5 mm from the applicator position. The mean D90(CTV) and V100(CTV) were 112% of the prescribed dose (PD) and 98.1%PD, respectively, for the image-based plan, and 113%PD and 97.2%PD, respectively, for the conventional plan. The median CTVref/Vref was 0.23 for the image-based plan and 0.16 for the conventional plan (P = 0.01). The mean D0.1 cm(3) (mandible), D1 cm(3) (mandible), and D2 cm(3) (mandible) were 80.1%PD, 62.5%PD, and 55.7%PD, respectively, for the image-based plan, and 109.1%PD (P = 0.02), 82.4%PD (P = 0.005), and 74%PD (P = 0.004), respectively, for the conventional plan). Image-based treatment planning may achieve high-conformity radiotherapy for the CTV and decrease irradiated doses to the mandible.

Electron beam radiotherapy for tongue cancer using an intra-oral cone

To explain the adaptation technique using an intra-oral cone (IOC) for radiation therapy, and to determine the optimal schedule resulting in a high local control rate and an acceptable complication rate using direct electron beam radiation for the treatment of tongue cancer. Thirty patients with the tongue cancer (T1:T2:T3=16:11:3) were treated with 6-15 MeV electron radiation using an IOC. Twenty-six patients were treated with electron radiation using an IOC with or without an excisional biopsy. The other four patients were treated with a combination of the external beam radiation and electron radiation using the IOC. In order to formulate a safe and effective treatment program, we calculated the biologically effective dose (BED). The two- and five-year local control rates for all patients were 63% and 52%, respectively. The two- and five-year overall survival rates for all patients were 73% and 69%, respectively. Local control was achieved in 12 of 15 patients who were irradiated with a BED of 90.9 Gy(10) or more, whereas it was not achieved in nine of the 15 patients who were treated with less than a BED of 90.9 Gy(10) (p=0.03). The application of electron radiation using an IOC for the treatment of tongue cancer provides acceptable local control and adverse effect rates, especially for elderly patients considered to be high risk for complications from anesthesia. The optimum BED(10) value for the treatment of early tongue cancer using the IOC technique appears to be at least 90.9 Gy(10).

Hyperfractionated high-dose rate brachytherapy in the treatment of oral tongue cancer

BACKGROUND

Low-dose rate brachytherapy is a well established treatment modality of oral cancer. Data about high-dose rate (HDR) brachytherapy are still sparse with various fractionation schedules and heterogeneous results.

AIM

The aim of our retrospective study was to evaluate the results of HDR brachytherapy with doses of 3 Gy twice daily.

PATIENTS AND METHODS

Twenty patients with squamous cell tongue cancer were treated in the years 2001-2009 by exclusive HDR BT 18 × 3 Gy twice daily. The plastic tube technique was used. Median follow up was 47 months (7.8-118) since brachytherapy.

RESULTS

The local and locoregional control was 85% and 68%, respectively. Bone necrosis developed in one case treated without mandibular shielding and soft tissue necrosis in 2 cases.

CONCLUSION

It can be concluded that HDR brachytherapy with 18 × 3 Gy twice daily is safe with promising local control. The risk of nodal recurrences is substantial.

Stage I and II mobile tongue carcinomas treated by external radiation and gold seed implantation

The purpose of this study was to analyze the influence of a protocol modification, in which the use of gold seeds was extended and elective neck irradiation was applied, on the treatment results of early carcinoma of the tongue. We analyzed 225 patients with Stage I (93 patients) and Stage II (132 patients) squamous cell carcinomas of the oral tongue. We compared the results between the two periods before (171 patients) and after (54 patients) the modification. The main alterations were the expanded use of gold seeds for tumors less than 5 mm in thickness and the application of elective irradiation for T2 tumors. The 5-year primary control and survival rates improved from 81% to 97% and from 81% to 93%, respectively. The occurrence of late complications-lingual muscle and mandibular bone necroses-was found not to deteriorate after the modification. We concluded that the modification was adequate.

Exclusive low-dose-rate brachytherapy in 279 patients with T2N0 mobile tongue carcinoma

PURPOSE

To evaluate the therapeutic results obtained with (192)Ir low-dose-rate interstitial brachytherapy in T2N0 mobile tongue carcinoma.

PATIENTS AND METHODS

Between December 1979 and January 1998, 279 patients with T2N0 mobile tongue carcinoma were treated by exclusive low-dose-rate brachytherapy, with or without neck dissection. (192)Ir brachytherapy was performed according to the "Paris system" with a median total dose of 60 Gy (median dose rate, 0.5 Gy/h).

RESULTS

Overall survival was 74.3% and 46.6% at 2 and 5 years. Local control was 79.1% at 2 years and regional control, respectively, 75.9% and 69.5% at 2 and 5 years (Kaplan-Meier method). Systematic dissection revealed 44.6% occult node metastases, and histologic lymph node involvement was identified as the main significant factor for survival. Complication rate was 16.5% (Grade 3, 2.9%). Half of the patients presented previous and/or successive malignant tumor (ear-nose-throat, esophagus, or bronchus).

CONCLUSION

Exclusive low-dose-rate brachytherapy is an effective treatment for T2 tongue carcinoma. Regional control and survival are excellent in patients undergoing systematic neck dissection, which is mandatory in our experience because of a high rate of occult lymph node metastases.

The biological effect of pentoxifylline on the survival of human head and neck cancer cells treated with continuous low and high dose-rate irradiation

AIM

The aim of this study was to compare the radiosensitivity effect of the G2/M arrest-abrogating substance, pentoxifylline (PTX), with high dose-rate irradiation (HDRI) and low dose-rate irradiation (LDRI), during which DNA repair and cell proliferation occur.

METHODS

Three squamous cell carcinoma cell lines, FaDu, RPMI 2650 and SCC-61, with differences in genomic imbalance and intrinsic radiosensitivity, were irradiated with 140 cGy/min (HDRI) and 0.7 cGy/min (LDRI) in the presence and absence of 2.0 mM PTX. The surviving fraction at 2.0 Gy (SF2) and cell-cycle phase distribution were assessed by DNA flow cytometry analysis and bromodeoxyuridine incorporation.

RESULTS

With HDRI and LDRI the SF2 of FaDu cells decreased by 38.5% and 27.6%, respectively, while the corresponding figures for RPMI 2650 were 28.5% and 48.5%, and for SCC-61 were 44.2% and 28.6%. Increases in G2 populations were evident after both HDRI and LDRI of all cell lines.

CONCLUSIONS

The enhancement in the cytotoxic effect of PTX was statistically significant after HDRI as well as after LDRI in all three cell lines. We therefore conclude that PTX in combination with LDRI is worth further study, both in vitro, for disclosing underlying mechanisms, and in vivo, to confirm the findings.

Effect of treatment time on outcome of radiotherapy for oral tongue carcinoma

PURPOSE

To investigate the importance of total treatment time on the outcome of external beam radiotherapy (EBRT) followed by internal brachytherapy for the treatment of oral tongue carcinoma.

METHODS AND MATERIALS

Ninety-four patients with T1-T2N0 squamous cell carcinoma of the oral tongue were treated using 35-40 Gy EBRT followed by 35-40 Gy interstitial (137)Cs brachytherapy between 1985 and 1995. The interval between the end of EBRT and the start of interstitial treatment varied for numerous unavoidable reasons, with a mean of 25.3 days and standard deviation of 3.5 days. The median follow-up period was 59.1 months (range 6-146).

RESULTS

The actuarial survival rate of all cases was 78.4% at 5 years. The 5-year local control rate for those with T1 and T2 was 92.8% and 62.7%, respectively (p < 0.05). The local control rate of the primary tumor in patients with a total treatment time >43 days was statistically lower than that of patients with a total treatment time < or =43 days in all patients (p < 0.05) and in the subgroup of Stage T2 patients (p < 0.05). Multivariate analysis revealed that the local control rates in all cases were significantly related to the T stage (T2 or not), total treatment time (>43 days or not), and location of disease (posterior or not). Regression analysis for 5-year local control as a function of treatment duration showed a 2% loss of local control per day of treatment extension >30 days (r = 0.94, p < 0.01).

CONCLUSION

The total treatment time was associated with the local control rate in the RT of oral tongue carcinoma. The loss in local control was estimated to be 2.0% per additional day in our series for oral tongue carcinoma.

Results of low- and high-dose-rate interstitial brachytherapy for T3 mobile tongue cancer

PURPOSE

To evaluate the treatment results of low-dose-rate (LDR) and high-dose-rate (HDR) interstitial brachytherapy (ISBT) for T3 mobile tongue cancer.

MATERIAL AND METHODS

Between 1974 and 1992, 61 patients with T3 mobile tongue cancer were treated with LDR ISBT using (192)Ir hairpins with or without single pins. In addition, between 1991 and 1999, 14 patients were treated with HDR ISBT. For nine patients treated with ISBT alone, the total dose was 59-94 Gy (median 72 Gy) within one week in LDR ISBT and 60 Gy/10 fractions/5 days in HDR ISBT. For 66 patients treated with a combination therapy of external beam radiotherapy (EBRT) and ISBT, the total dose was 12.5-60 Gy (median 30 Gy) of EBRT and 50-112 Gy (median 68 Gy) within 1 week in LDR ISBT or 32-60 Gy (median 48 Gy)/8-10 fractions/5-7 days in HDR ISBT.

RESULTS

The 2- and 3-year local control rates of all patients were both 68%. The 2- and 3-year local control rates of patients treated with LDR ISBT were both 67%, and those with HDR ISBT were both 71%. The local control rate of patients treated with HDR ISBT was similar to those with LDR ISBT.

CONCLUSIONS

ISBT for T3 mobile tongue cancer is effective and acceptable. The treatment result of HDR ISBT is almost similar to that of LDR ISBT for T3 mobile tongue cancer.

[Brachytherapy in head and neck cancers]

Experience accumulated over several decades with radiation of Head and Neck tumours by irradiation has demonstrated the need for a high tumour dose to achieve local control. With external beam irradiation alone, it is difficult to spare adjacent normal tissues, resulting in undesirable late effects on the salivary glands, mandible, and muscles of mastication. Interstitial implantation is ideally suited to deliver a high dose limited to the volume of the primary tumor, thus minimizing sequels. A large experience has been accumulated with low dose rate (LDR) brachytherapy in treatment of carcinoma of oral cavity, oropharynx, and nasopharynx. Recent analysis of large clinical series provided data indicating that modalities of low dose rate brachytherapy should be optimized in treating these tumors for increasing therapeutic ratio. Low dose rate brachytherapy is now challenged by high dose rate (HDR) brachytherapy and pulsed dose rate (PDR) brachytherapy. Preliminary results obtained with these two last modalities are discussed regarding to those of low dose rate brachytherapy.

Interstitial brachytherapy with or without external beam irradiation in head and neck cancer: Institute Rotary Cancer Hospital experience

Iridium-192 interstitial brachytherapy is practiced infrequently in developing countries, even where head and neck cancer is a major neoplasm and the technique could provide good results. This report from India is presented as an audit to validate the benefit of brachytherapy. One hundred and six head and neck cancer patients were treated by interstitial brachytherapy alone (n = 29) or combined with external irradiation (n = 77). The oral cavity and the oropharynx together constituted 82% of the sites of implanted tumours; 75% were T(1-2)N0 status. Brachytherapy was carried out using afterloaded plastic catheters and the Paris dose prescription system was followed. External cobalt-60 beam portals covered the primary and the neck. The median duration of follow-up was 22 months. The median dose of brachytherapy used alone was 60 Gy. With combined treatment, the median external radiotherapy and brachytherapy doses were 50 Gy and 25 Gy respectively. The median brachytherapy dose rate was 0.5 Gy/h. Primary and nodal recurrences were recorded in 41/106 (38.7%) and 18/106 (17.0%) patients at median intervals of 15 and 13 months respectively. Implant site failure was more common after combined treatment than with brachytherapy alone (42.8% versus 27.5%), but it did not reach statistical significance in this analysis (P = 0.15). Kaplan-Meier actuarial 5-year estimates showed 52% and 87% disease-free and overall survivals. Iridium-192 interstitial implants in suitably selected head and neck cancer patients can improve the radiotherapeutic results, with the promise of organ conservation in 50%. In India, the practice should be established in more radiotherapy centres and could be utilized in 10,000-25,000 head and neck cancer patients annually.

Head and neck brachytherapy

Experience accumulated over several decades in the treatment of head and neck tumors by irradiation has demonstrated the need for a high tumor dose to achieve local control. With external beam irradiation alone, it is difficult to spare adjacent normal tissues, resulting in undesirable late effects on the salivary glands, mandible, and muscles of mastication. Interstitial implantation is ideally suited to deliver a high dose limited to the volume of the primary tumor, thus maximizing tumor control while minimizing complications. A large experience has been accumulated with low dose rate (LDR) brachytherapy in treatment of carcinoma of oral cavity, oropharynx, and nasopharynx. Recent analysis of large clinical series provided data indicating that modalities of LDR brachytherapy should be optimized in treating these tumors for increasing therapeutic ratio. LDR brachytherapy is now challenged by high dose rate (HDR) brachytherapy and pulsed dose rate (PDR) brachytherapy. Preliminary results obtained with these 2 last modalities will be discussed.

Brachytherapy for prostate cancer in Japan

The temporary implantation of iridium-192 (Ir-192) is available in Japan if the patient is isolated in a radiation control area during the treatment. In this study, brachytherapy for prostate cancer was preceded by using low-dose rate Ir-192. Twenty-six patients with localized prostate cancer were treated with brachytherapy since December 1997. The age of patients ranged from 61 to 82 (median 76) years and the initial serum prostate-specific antigen (PSA) level ranged from 4.3 to 141 (median 17.4) ng/ml. Ten to 14 needles with Teflon sheaths were introduced into the prostate via a transperineal approach and an Ir-192 wire was placed in each sheath. The dose-distribution curve based on computed tomography imaging was drawn and the irradiation time was calculated for the whole prostate to receive over 70 Gy. During the 1-22-month follow-up period, all cases with an initial PSA level of less than 25 ng/ml showed continuous PSA decrease without biochemical failure. Magnetic resonance imaging demonstrated tumor regression in all cases within 6 months after the treatment. One-year biopsy specimens from patients with PSA failure demonstrated viable tumor cells, and the specimens from patients with favorable progress revealed fibrosis replacement without any variable tumor cells. Characterization of nocturnal penile tumescence data and IIEF 15 score proved the minimal effect of the treatment on erectile function. No major side effects or complications were observed. Brachytherapy using Ir-192 is a less invasive and safe procedure, which is expected to become a standard treatment for localized prostate cancer patients with relatively low PSA levels.

Pulsed dose rate brachytherapy in head and neck cancers. Feasibility study of a French cooperative group

PURPOSE

To prospectively evaluate the feasibility of pulsed dose rate (PDR) brachytherapy to mimic the continuous low dose rate (cLDR) iridium wire technique in head and neck carcinomas.

MATERIALS AND METHODS

A series of 30 patients were included from June 1995 to May 1998. The primaries were located in the oral cavity (four T1, seven T2 and two T3), the velotonsillar arch (eight T1 and eight T2) and the posterior wall (one T3). Thirteen were irradiated by exclusive brachytherapy (dose, > or =45 Gy). The PDR delivered 0.5 Gy/pulse, one pulse/h, day and night, to mimic cLDR irradiation.

RESULTS

The implantation was feasible for all the patients, usually easy and of good quality. The mean duration/pulse was 13 min, with a mean source activity of 171 mCi. Patient tolerance was poor in nine cases. Sixteen patients could receive the whole PDR treatment with a total ranging from 30 to 120 pulses without any problem. Seven had short breakdowns (< or =6 h). Seven had definitive breakdowns, but could end the irradiation by manual afterloading of iridium 192 wires. The radioprotection was better (or complete), except for one patient. Most of the breakdowns were related to kinking or flattering of the tube.

CONCLUSIONS

PDR is feasible in head and neck carcinomas, but necessitates improvement of the quality and control of the plastic tubes.

[Retrospective analysis of results of treatment of 91 oral cavity cancers from 1982 to 1992]

PURPOSE

To analyse retrospectively the results of different treatment regimens of carcinomas of the floor of the mouth and tongue.

MATERIALS AND METHODS

Between 1982 and 1992, 61 patients with carcinoma of the floor of the mouth and 30 with tongue cancer (25 stage I, nine stage II, 28 stage III, 29 stage IV) were treated in the radiotherapy department of Poitiers. Nine patients with stage I tumours were treated with 70 Gy low-dose rate brachytherapy only, without nodal dissection. Stages II and III were treated with combined surgery with neck dissection; and radiotherapy of stage II with nodal metastasis and for all stage III cases. Stage IV cases were treated either surgically if possible, or with combined chemotherapy and radiation.

RESULTS

The five-year overall survival rate was 87.3% for stage I, 68.5% for stage II, 45.3% for stage III, and 0% for stage IV patients. Most relapses appeared in the first two years after treatment. Eight patients (32%) with stage I cancer developed nodal relapses, isolated in five cases. Complications of radiotherapy were acceptable. Four cases of osteonecrosis were observed after radiotherapy. All of these appeared simultaneously with a local relapse.

CONCLUSION

These results are comparable with reports in the literature. The remarkable observation of our study is the high incidence of nodal recurrences after local treatment of stage I tumours. Therefore, local treatment is insufficient for early-stage tumours. The question of neck dissection for the early stage is discussed.

High-dose-rate brachytherapy for primary carcinomas of the oral cavity and oropharynx

OBJECTIVE

Local control for patients treated with primary radiation therapy for tumors of the oral cavity is improved using low-dose-rate brachytherapy. Oropharyngeal carcinomas have also been treated with brachytherapy. The few reports in the literature regarding high-dose-rate brachytherapy (HDRBT) for head and neck cancer involve small numbers of patients and often contain a mix of palliative and curative cases. The purpose of this study is to evaluate the feasibility of HDRBT in the largest reported cohort of primary head and neck cancer patients treated with primary radiation therapy.

STUDY DESIGN

This is a prospective nonrandomized study.

METHODS

Fifty-five patients with primary untreated squamous cell carcinomas of the oral cavity and oropharynx were analyzed. There were 16 patients with T1, 26 with T2, 8 with T3, and 5 with T4 tumors. All patients received external-beam radiotherapy (EBRT) followed by HDRBT. Thirty-eight patients received hyperfractionated (twice daily) EBRT followed by HDRBT two or three times daily. Patients with cervical adenopathy also received hyperthermia and an electron boost to the site(s) of positive nodes. Median follow-up was 2.7 years. Toxicity and local control were analyzed. Data were analyzed by the Kaplan-Meier life-table method with statistical significance determined by the X2 and log-rank tests.

RESULTS

High-dose-rate brachytherapy was extremely well tolerated. Only 9 patients (16%) developed a complication. Four patients developed osteoradionecrosis, and five developed soft tissue necrosis, all of which healed with conservative medical management. No complication required surgical intervention or hospitalization. Actuarial 2-year local control for the entire cohort was 79%. Local control was 87% for patients with T1 (15/16) and T2 (22/26) tumors versus 47% for T3 (5/8) and T4 (2/5) tumors (P < .01).

CONCLUSIONS

High-dose-rate brachytherapy is feasible as a boost for patients with primary squamous cell carcinomas of the oral cavity and oropharynx. Patients with T1 and T2 tumors fared exceptionally well; those with advanced tumors may require more aggressive treatment, such as higher radiation doses, surgical resection, or systemic chemotherapy. The use of HDRBT both shortens the overall treatment time and limits the volume of tissue exposed to high doses of radiation therapy. In the future, as more patients treated with HDRBT are evaluable, we hope to identify potential factors that predict for local control so that we may select patients optimally for this treatment.

Surgical management of head and neck cancer

Head and neck cancer surgery continues to evolve through the years and undergo improvement and refinement. In this article, the current state of head and neck cancer surgery is summarized in a site-by-site basis. The most important developments include organ-sparing surgery and microvascular free-tissue transfer for reconstruction.

Interstitial brachytherapy for stage I and II squamous cell carcinoma of the oral tongue: factors influencing local control and soft tissue complications

PURPOSE

Our aim was to study the treatment parameters that influence local control and soft tissue complications (STC) in a series of 207 Stage I and II squamous cell carcinomas of the oral tongue treated by interstitial brachytherapy (BRT) alone (127 patients), or by a combination using external beam irradiation (EBI) (80 patients) between 1980 and 1993.

METHODS AND MATERIALS

The patient distribution was 93 T1, 72 T2a, and 42 T2b. The prescribed BRT dose at the plane 5 mm from the plane of the radioactive sources was 65-70 Gy in BRT alone, and 50-60 Gy in the combined treatment using EBI. Generally, an EBI dose of 30 Gy was used. No prophylactic neck treatment was performed.

RESULTS

The 5-year local recurrence-free rate for T1, T2a, and T2b was 92.9%, 81.9%, and 71.8%, respectively (p < 0.05). The lesions of endophytic appearance and those located in the posterior half of the mobile tongue had a significantly lower local control rate than those of other macroscopic appearances (p = 0.02) and those in other localizations (p < 0.01). Most local recurrences (66.7%) occurred within 2 years after treatment. However, 8 of 14 recurrences of T1 and 6 of 15 recurrences among patients treated by BRT alone occurred after 5 years. Statistical analysis showed that, in BRT alone treatment, a dose rate < = 1.0 Gy/h was related to better local control (p = 0.04). There was no significant relationship between BRT dose and local control; however, the incidence of local recurrence was lowest in a BRT dose 65-70 Gy. In the combined treatment, a total dose > 85 Gy (p = 0.01), BRT dose > 55 Gy (p = 0.04), and a dose rate < 0.55 Gy/h (p = 0.03) were significantly related to better local control. The incidence of more severe STC were 11.5% and was significantly higher in T2a (p = 0.03) and T2b (p < 0.01) than in T1. Statistical analysis revealed that a dose rate > = 0.6 Gy/h was significantly related to more STC in BRT alone (p = 0.03), and that a dose rate > = 0.55 Gy/h (p < 0.03) and a BRT dose > 70 Gy ( < 0.05) and a total dose > 100 Gy (p < 0.05) were significantly related to more STC in the combined treatment. Neck metastases occurred in 25% in T1N0, 27% in T2aN0, and 31% in T2bN0 (NS). Eighty-eight percent were found within 12 months. Thirty-three secondary cancers including 12 head and neck, 8 esophageal, and 3 gastric were found after treatment. The 5-year crude survival rate for T1, T2a, and T2b was 83.4%, 66.0%, and 70.9%, respectively.

CONCLUSION

To acheive better local control and fewer STC, we recommend the following relationships between dose and dose rate. In BRT alone, dose rate should be maintained at < 0.6 Gy/h with a preferable BRT dose 65-70 Gy. In the combined treatment, total dose, BRT dose and dose rate should be kept between > 85 Gy and < = 100Gy, between > 55 Gy and < = 70 Gy, and < 0.55 Gy/h, respectively. We also recommend longer follow-up periods; more than 5 years might be necessary for late local recurrences and for secondary cancers.

How to optimize therapeutic ratio in brachytherapy of head and neck squamous cell carcinoma?

Considerable experience has been accumulated with low dose rate (LDR) brachytherapy in the treatment of squamous cell carcinoma of the oral cavity and oropharynx, 4 cm or less in diameter. Recent analysis of large clinical series provided data indicating that modalities of LDR brachytherapy should be optimized in treating these tumours for increasing therapeutic ratio. LDR brachytherapy is now challenged by high dose rate (HDR) brachytherapy and pulsed dose rate (PDR) brachytherapy. Preliminary results obtained with the last two modalities are discussed in comparison with those achieved with LDR brachytherapy.

Modern brachytherapy: current state and future prospects

This article reviews the current trends and future developments in brachytherapy. Established techniques including interstitial and high-dose rate brachytherapy are discussed with particular reference to lung, oesophageal, cervical and endometrial cancer. Intra-operative high-dose rate brachytherapy and other new techniques are also mentioned.

A prospective quality of life study of patients with oral or pharyngeal carcinoma treated with external beam irradiation with or without brachytherapy

The aim of this longitudinal quality of life (QL) study, was to study tumour-related symptoms and treatment side-effects of patients with oral or oropharyngeal cancer and to determine whether an increased local dose of irradiation (brachytherapy affected QL. The European Organisation for Research and Treatment of Cancer Quality of Life Core Questionnaire (EORTC QLQ-C30), a tumour-specific Head and Neck questionnaire and the Hospital Anxiety and Depression scale (HAD) were used repeatedly during 1 year. There were 105 patients, with a cumulative response rate of 89%. Most symptoms and problems were at their peak 2 or 3 months after the start of treatment. Nutrition and pain were found to be the major problems, and as many as 19-40% reported psychiatric distress. Patients having received additional brachytherapy did not report any increase in QL problems (except for pain) compared with those having had external radiation only. Quality of life does not seem to be affected by the increased irradiation local dose given when brachytherapy is included in the treatment regimen.

Role of Interstitial Brachytherapy in Oral and Oropharyngeal Carcinoma: Reflection of a Series of 1344 Patients Treated at the Time of Initial Presentation

Our study focuses on a series of 1344 cases of carcinoma of the oral cavity and oropharynx treated between 1973 and 1992. Brachytherapy was always performed with iridium 192, either alone or in combination with external-beam irradiation or with surgery for the treatment of the primary tumor. For the oral cavity, we studied 565 cases of mobile tongue. The local control and overall survival rates, respectively, at 5 years are as follows: for T1, 92% and 70%; for T2, 62% and 42%; and for T3, 50% and 29%. For the subgroup T1T2N0, there was a better prognosis for treatment by brachytherapy of the primary lesion alone ( p < 0.0001). Two hundred seven cases of floor-of-mouth carcinoma have been reported. The T3T4 patients were not considered surgical candidates. The local control and overall survival rates, respectively, at 5 years are as follows: for T1, 97% and 71%; for T2, 72% and 42%; and for T3, 51% and 35%. Ninety-seven patients were treated by postoperative brachytherapy. These were patients for whom the margins after surgery were positive or narrow. A technique termed the modified bridge is described for lesions located in the mandible. Carcinomas of the buccal mucosa are rare in our country; only 42 cases were treated in this comparison of two techniques, and the overall survival rate was 48%. Epidermoid carcinomas of the oropharynx have nearly always been treated by a combination of external-beam irradiation and brachytherapy because of the bilateral node risk. Seventy-two patients with epidermoid cancers of the base of the tongue had an overall survival rate of 44%. The tonsil, soft palate, and pillars benefited from the use of the loop technique of brachytherapy combined with external-beam irradiation. Three hundred sixty-one patients were treated. Among these patients were two groups with different prognoses. Patients with tonsil, soft palate, and posterior pillar carcinomas had a local control rate of 84% and an overall survival rate of 57%. Conversely, the anterior pillar and the pharyngoglossal sulcus have a local control rate of only 65% and an overall survival rate of 38%. Statistical analysis revealed the prognostic factors for local control. The complications were classified into four grades: minor (20%), moderate (9%), major (4%), or inducing death (0.2%). The bone complications of grade 2 or 3 are more frequent for the floor of the mouth than for other locations.

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 of oral cancers using iridium-192 interstitial irradiation

OBJECTIVE

To assess retrospectively the outcome and morbidity of Iridium-192 brachytherapy in the treatment of oral cancers.

DESIGN

Retrospective audit of cases treated between 1981 and 1991.

SETTING

Newcastle upon Tyne, England.

SUBJECTS

73 patients with oral cancer treated with Iridium-192.

MAIN OUTCOME MEASURES

Local control, crude and cause specific survival, and local morbidity.

RESULTS

Seventy four cases of squamous cell carcinoma of the oral cavity were treated using interstitial Iridium-192. The disease specific 5-year survival rates were 69% for T1, 67% for T2, and 0% for T3 tumours. Mortality from recurrent cancer was 20%, and from intercurrent disease was 28%. The incidence of major radiation induced morbidity was 11%, and the local control rate was 81% for T1, 69% for T2, and 50% for T3 tumours.

CONCLUSION

Interstitial radiotherapy remains a viable and valuable mode of treatment for a small proportion of patients presenting with early (T1 and T2) oral cancers.

The study of tumoral, radiobiological, and general health factors that influence results and complications in a series of 448 oral tongue carcinomas treated exclusively by irradiation

PURPOSE

Our aim was to study the different factors that influence the results and complications in a series of 448 carcinomas of the oral tongue treated from January 31, 1972 to December 31, 1986, by brachytherapy (Br) +/- neck dissection (181 cases) or combination of external beam irradiation and brachytherapy (EBI + Br) (267 cases).

METHODS AND MATERIALS

The patients distribution (TNM classification 1979) was: 125 T1, 186 T2, 128 T3, 9 T4Tx, 78% N0, and 22% N+. We used guide gutter or plastic tubes technique (Paris system dosimetry). Results at 5 and 10 years are: local control 68% and 64%, locoregional control 58% and 53%, specific survival 45% and 39%, and overall survival 44% and 27%.

RESULTS

In the univariate analysis for local control (LC) and overall survival (OS), we considered the tumoral factors. At 5 years, the LC for T1, T2, T3 are 93%, 65%, and 49%, and the OS 69%, 41%, and 25%, respectively (p < 0.002). The lesions of the undersurface of the tongue have a better LC (77%) than other localizations (64%) (p = 0.02). For general factors, the index of general health condition, age, and sex were not significant for LC, but proved significant for OS (p = 0.01). Significant radiobiological factors: the safety margin (expressed by the ratio treated surface on tumoral surface > or = 1.2) is significant for LC and OS. This is the same if the interval between EBI and Br is < or = 20 days. Neither the dose rate, the spacing between the sources, the total dose, nor Br dose were significant, but the last two were adapted according to the infiltration. In the univariate study for grade 2 and 3 complications (tissue and bone), the surface treated (> 12 cm2), and the dose rate > 0.7 Gy/h were significant.

CONCLUSION

The multivariate study showed that the small size of the lesion is the most important factor for local control, with brachytherapy alone for T1T2N0 and the number of days between EBI and brachytherapy < or = 20 days. For the complications, the most important factors are the total dose > 80 Gy and a treated surface > 12 cm2.