125I vicryl suture implants as a surgical adjuvant in cancer of the head and neck

A Newly Designed Seed-Loading Device for Verifying the Safety of 125I Implants to the Canine Carotid Artery

A seed-loading device was designed and modeled using the Monte Carlo method to verify the biological effect of iodine-125 (125I) particles on blood vessels through animal experiments. The dose distribution characteristics of irradiated vessels were established by adjusting the design variables and geometry. The deviation between the actual value and the theoretical value was verified in vitro by the thermoluminescence dosimetry (TLD) method. After verification, the device was used to examine the biological effect of 125I irradiation of canine carotid arteries in two dogs (and one control dog) for 180 days. The hollow cylinder seed-loading device was constructed with an inner diameter of 0.5 cm and a length of 3.3 cm. When six seeds were loaded into a single layer, the source strength ratio of the intermediate layer to the edge layer was 0.7:1. When six layers of seeds were arranged at 0.45-cm intervals, the deviations between the maximum, minimum and mean energy fluence within 2.25 cm of the vessel wall were 2.19% and -4.12%, respectively, and -9% and 4%, respectively, when verified in vitro using TLD. The carotid arteries showed good tolerance to 0.56 kGy (range of 0.51-0.58 kGy) after 180 days of irradiation. In conclusion, this 125I seed-loading device overcomes the random distribution of seeds and lays an accurate radiophysical foundation for subsequent biological experiments. The preliminary results showed that the carotid artery has good tolerance to 0.56 kGy irradiation.

Surgery combined with postoperative 125 I seed brachytherapy for the treatment of mucoepidermoid carcinoma of the parotid gland in pediatric patients

BACKGROUND

This retrospective study was undertaken to analyze the effectiveness and safety of surgery combined with postoperative ¹²⁵ I seed brachytherapy in the treatment of mucoepidermoid carcinoma (MEC) of the parotid gland with risk factors in pediatric patients.

PROCEDURE

From September 2002 to January 2012, 24 patients, ages 5-16 years (mean, 13.2 years; median, 12.3 years), with MEC of the parotid gland were included. Patients with high risk factors received ¹²⁵ I seed brachytherapy (median actuarial D90, 97 Gy) within 4 weeks following surgery. Radioactivity was 18.5-33.3 MBq per seed and the prescription dose was 60-120 Gy. Overall and disease-free survival rates, local control rate, and distant metastasis were recorded. Radiation-associated late side effects, including dermatitis, hearing loss, thyroid nodules, and secondary malignancy, were also evaluated.

RESULTS

During the follow-up period of 5-13.4 years (median, 7.2 years), the overall and disease-free survival rates were all 100%. No patients developed local recurrence, regional/distant metastasis, and no severe radiation-associated complications including the second malignancy were noted.

CONCLUSION

Surgery combined with postoperative ¹²⁵ I seed brachytherapy is effective and safe in the treatment of MEC of the parotid gland in pediatric patients, with no evidence of severe late radiation-related complications. More patients and longer follow-up data are still needed to prove the efficacy of ¹²⁵ I brachytherapy.

Clinical application of computed tomography-guided (125)I seed interstitial implantation for head and neck cancer patients with unmanageable cervical lymph node metastases

Background

To assess clinical application of computed tomography (CT)-guided ¹²⁵I seed implantation for patients who cannot endure or unwillingly receive repeated surgery, chemotherapy, or radiotherapy for unmanageable cervical lymph node metastases in head and neck cancer (HNC).

Methods

Thirty-one consecutive patients received CT-guided ¹²⁵I seed implantation between February 2010 and December 2013. To evaluate the clinical efficiency, karnofsky performance score (KPS), numeric rating scale (NRS), and tumor volume at 3-, and 6-month post-implantation were compared with pre-implantation, along with local control rate (LCR), overall survival rate (OSR), and complications at 3, 6 months, 1, and 2 years.

Results

The tumor volume was obviously decreased at 3-, and 6-month post-implantation (21.23 ± 8.83 versus 9.19 ± 7.52 cm²; 21.23 ± 8.83 versus 6.42 ± 9.79 cm²; P < 0.05) compared with pre-implantation. The NRS was statistically reduced (3.06 ± 1.06 versus 7.77 ± 0.92; 2.39 ± 1.15 versus 7.77 ± 0.92; P < 0.05), while KPS was significantly improved (83.18 ± 5.97 versus 73.60 ± 7.90; 82.86 ± 5.43 versus 73.60 ± 7.90; P < 0.05) postoperatively at 3 and 6 months, respectively. The LCR at 3, 6 months, 1, and 2 years was 96.30, 83.87, 64.51, and 45.16 %, respectively. The OSR was 100, 100, 67.74, and 45.16 %, respectively. Three cases experienced grade I and two had grade II acute radiation toxicity.

Conclusions

CT-guided seed implantation may be feasible and safe for HNC patients whose neck nodes are not manageable by routine strategies with fewer complications, higher LCR, and significant pain relief.

Modern head and neck brachytherapy: from radium towards intensity modulated interventional brachytherapy

Intensity modulated brachytherapy (IMBT) is a modern development of classical interventional radiation therapy (brachytherapy), which allows the application of a high radiation dose sparing severe adverse events, thereby further improving the treatment outcome. Classical indications in head and neck (H&N) cancers are the face, the oral cavity, the naso- and oropharynx, the paranasal sinuses including base of skull, incomplete resections on important structures, and palliation. The application type can be curative, adjuvant or perioperative, as a boost to external beam radiation as well as without external beam radiation and with palliative intention. Due to the frequently used perioperative application method (intraoperative implantation of inactive applicators and postoperative performance of radiation), close interdisciplinary cooperation between surgical specialists (ENT-, dento-maxillary-facial-, neuro- and orbital surgeons), as well interventional radiotherapy (brachytherapy) experts are obligatory. Published results encourage the integration of IMBT into H&N therapy, thereby improving the prognosis and quality of life of patients.

An investigation of 125I seed permanent implantation for recurrent carcinoma in the head and neck after surgery and external beam radiotherapy

BACKGROUND

A preliminary assessment was conducted of the feasibility, efficacy, and morbidity of 125I seed implantation for recurrent head and neck carcinoma after surgery and external beam radiotherapy.

METHODS

Nineteen patients with recurrent head and neck carcinomas underwent 125I seed implantation under ultrasound or computed tomography guidance. The actuarial D90 of 125I seed implantation ranged from 90 to 160 Gy (median, 131 Gy). The follow-up period ranged from 3 to 44 months (median, 11 months).

RESULTS

The median local control was 24 months (95% confidence interval, 10.2 to 37.8). The one- year, two-year and three-year local controls were 73.3%, 27.5% and 27.5%, respectively, whereas the one-year, two-year and three-year survival rates were 53.0%, 18.2% and 18.2%, respectively, and the median survival was 13 months (95% confidence interval, 6.6 to 19.4). A total of 26.3% of patients (5/19) died of local recurrence and 21.1% of patients (4/19) died of metastases. One suffered from a grade 1 skin reaction.

CONCLUSIONS

125I seed implantation is feasible and safe as a salvage treatment for patients with recurrent head and neck cancers. The high local control results and low morbidity merits further investigation.

Postoperative 125I brachytherapy delivered by digital model obturators for recurrent or locally advanced maxillary cancers

OBJECTIVES/HYPOTHESIS

We aimed to evaluate the feasibility and effectiveness of postoperative (125) I brachytherapy delivered by use of digital model obturators for recurrent or locally advanced maxillary cancers.

STUDY DESIGN

Retrospective study.

METHODS

From 2006 to 2008, 12 patients (seven females; median age, 65 years; range, 22-86 years) with recurrent or locally advanced maxillary cancers showing positive margins after surgery underwent (125) I brachytherapy by use of digital model obturators and interstitial implants. The radioactivity was 18.5 to 33.3 MBq per seed, and the prescription dose was 80 to 160 Gy. Functional outcome of patients was evaluated by the Performance Status Scale (PSS) for head and neck cancer before and after brachytherapy.

RESULTS

The (125) I seeds and dosages were well distributed in the radiation fields, and all patients had higher PSS scores after than before treatment with obturators. During a median follow-up of 53 months (range, 28-62 months), local control at 3 and 5 years was 83.3% and 66.7%, respectively, with a mean local control time of 53.5 ± 3.79 months. Overall survival at 3 and 5 years was 91.7% and 71.4%, respectively, with a mean survival time of 56.6 ± 2.99 months. Two patients died due to local recurrence, and one patient died due to lung metastasis. No patient had severe complications during follow-up.

CONCLUSIONS

(125) I brachytherapy delivered by digital model obturator is effective in treating maxillary cancers with positive margins after maxillectomy for advanced or recurrent cancer. The method may improve the quality of life of patients with maxillary defects. Laryngoscope, 2012.

CT-guided iodine-125 seed permanent implantation for recurrent head and neck cancers

BACKGROUND

To investigate the feasibility, and safety of 125I seed permanent implantation for recurrent head and neck carcinoma under CT-guidance.

RESULTS

A retrospective study on 14 patients with recurrent head and neck cancers undergone 125I seed implantation with different seed activities. The post-plan showed that the actuarial D90 of 125I seeds ranged from 90 to 218 Gy (median, 157.5 Gy). The follow-up was 3 to 60 months (median, 13 months). The median local control was 18 months (95% CI, 6.1-29.9 months), and the 1-, 2-, 3-, and 5- year local controls were 52%, 39%, 39%, and 39%, respectively. The 1-, 2-, 3-, and 5- survival rates were 65%, 39%, 39% and 39%, respectively, with a median survival time of 20 months (95% CI, 8.7-31.3 months). Of all patients, 28.6% (4/14) died of local recurrence, 7.1% (1/14) died of metastases, one patient died of hepatocirrhosis, and 8 patients are still alive to the date of data analysis.

CONCLUSION

CT-guided 125I seed implantation is feasible and safe as a salvage or palliative treatment for patients with recurrent head and neck cancers.

Manually after-loaded 192Ir low-dose rate brachytherapy after subtotal excision and flap reconstruction of recurrent cervical lymphadenopathy from head and neck cancer

BACKGROUND

Treatment of extensive recurrent cervical lymph node metastases from previously irradiated head and neck cancer represents a difficult clinical challenge. We report the results of an approach of maximal surgical debulking and manually after-loaded intra-operative brachytherapy.

PATIENTS AND METHODS

Seventy-four procedures were carried out at the Royal Marsden Hospital between 1979 and 2003. All patients had previously been treated with radical radiotherapy or chemoradiation. Patients underwent maximal surgical debulking, followed by brachytherapy to the tumour bed with low-dose rate (192)Ir to a dose of 60 Gy to the reference isodose using the Paris system.

RESULTS

Overall and disease specific survival rates were 31% and 28% at two years and 23% and 17% at five years. Corresponding Loco-regional control rates were 37% and 23%, respectively. Fifty per cent of patients developed metastatic disease within 5 years of treatment. Best results were obtained with surgical excision, brachytherapy and reconstruction of the skin defect using a vascularised myo-cutaneous flap with in-field control rates of 72% at two years and 66% at 5 years. Nine per cent of patients developed fistulae, 4% had haemorrhage and 8% wound breakdown/infection.

CONCLUSIONS

Maximal surgical debulking, including removal of overlying skin, and brachytherapy to the surgical tumour bed provides high levels of local control, and can be achieved with acceptable morbidity. Only a minority of patients achieve long-term survival because of the high risk of systemic relapse.

Treatment planning and delivery of intensity-modulated radiation therapy for primary nasopharynx cancer

PURPOSE

To implement intensity-modulated radiation therapy (IMRT) for primary nasopharynx cancer and to compare this technique with conventional treatment methods.

METHODS AND MATERIALS

Between May 1998 and June 2000, 23 patients with primary nasopharynx cancer were treated with IMRT delivered with dynamic multileaf collimation. Treatments were designed using an inverse planning algorithm, which accepts dose and dose-volume constraints for targets and normal structures. The IMRT plan was compared with a traditional plan consisting of phased lateral fields and a three-dimensional (3D) plan consisting of a combination of lateral fields and a 3D conformal plan.

RESULTS

Mean planning target volume (PTV) dose increased from 67.9 Gy with the traditional plan, to 74.6 Gy and 77.3 Gy with the 3D and IMRT plans, respectively. PTV coverage improved in the parapharyngeal region, the skull base, and the medial aspects of the nodal volumes using IMRT and doses to all normal structures decreased compared to the other treatment approaches. Average maximum cord dose decreased from 49 Gy with the traditional plan, to 44 Gy with the 3D plan and 34.5 Gy with IMRT. With the IMRT plan, the volume of mandible and temporal lobes receiving more than 60 Gy decreased by 10-15% compared to the traditional and 3D plans. The mean parotid gland dose decreased with IMRT, although it was not low enough to preserve salivary function.

CONCLUSION

Lower normal tissue doses and improved target coverage, primarily in the retropharynx, skull base, and nodal regions, were achieved using IMRT. IMRT could potentially improve locoregional control and toxicity at current dose levels or facilitate dose escalation to further enhance locoregional control.

The role of brachytherapy for palliation

The goal of palliative radiation is to alleviate symptoms in a short amount of time and maintain an optimal functional and quality-of-life level while minimizing toxicity and patient inconvenience. Despite advances in multimodality antineoplastic therapies, failure to control the tumor at its primary site frustratingly remains the predominant source of morbidity and mortality in many patients with cancer. Escalation of doses of radiation using external beam irradiation has been shown to improve local tumor control, but limits are imposed by the tolerance of normal surrounding structures. The highly conformal nature of brachytherapy enables the radiation oncologist to accomplish safe escalation of radiation doses to the tumor while minimizing doses to normal surrounding structures. Thus, by enhancing the potential for local control, brachytherapy used alone or as a supplement to external beam radiation therapy retains a significant and important role in achieving the goals of palliation. Proper patient selection, excellent technique, and adherence to implant rules will minimize the risk of complications. The advantages realized with the use of brachytherapy include good patient tolerance, short treatment time, and high rates of sustained palliation. This article reviews various aspects of palliative brachytherapy, including patient selection criteria, implant techniques, treatment planning, dose and fractionation schedules, results, and complications of treatment. Tumors of the head and neck, trachea and bronchi, esophagus, biliary tract, and brain, all in which local failure represents the predominant cause of morbidity and mortality, are highlighted.

The role of brachytherapy in head and neck cancer

By precision dose delivery to a well-defined target, brachytherapy fulfills the complementary goals of delivering sufficient dose for tumor cell kill while sparing normal adjacent structures. The unique properties of this modality, either used alone or implemented in a combined modality setting with surgery or external-beam irradiation, offer an ideal means of enhancing the therapeutic ratio by exploiting the effect of local therapies while respecting normal tissue tolerance. Brachytherapy also provides an effective technique for the retreatment of patients with recurrent, persistent, or second primary head and neck malignant tumors in a previously irradiated region. The benefits of this treatment modality are reflected in excellent reported local control rates, shortened overall treatment times, reduced functional deficits, improved quality of life, and decreased costs. Successful brachytherapy relies, however, on close collaborative efforts between radiation oncologists and surgeons, careful assessment of the patient, precise planning, and technique that adheres to the rules of a system. Brachytherapy has been clearly identified as an effective, safe, and appealing modality in the treatment of head and neck malignancies.

Close or positive margins after surgical resection for the head and neck cancer patient: the addition of brachytherapy improves local control

PURPOSE

Microscopically positive or close margins after surgical resection results in an approximately 21-26% local failure rate despite excellent postoperative external radiation therapy. We sought to demonstrate improved local control in head and neck cancer patients who had a resection with curative intent, and had unexpected, microscopically positive or close surgical margins.

METHODS AND MATERIALS

Twenty-nine patients with microscopically close or positive margins after curative surgery were given definitive, adjuvant external radiation therapy and 125I brachytherapy. All 29 patients had squamous cell cancer and tonsil was the most common subsite within the head and neck region. After external radiation therapy and thorough discussions with the attending surgeon and pathologists, the slides, gross specimens, and appropriate radiographs were reviewed and a target volume was determined. The target volume was the region of the margin in question and varied in size based on the surgery and pathologic results. Once the target volume was identified the patient was taken back to the operating room for insertion of 125I seeds. Activity implanted (range 2.9-21.5 millicuries) was designed to administer a cumulative lifetime dose of 120-160 Gy.

RESULTS

Twenty-nine patients were followed for a median of 26 months (range 5-86 months). Two-year actuarial local control was 92%.

CONCLUSION

125I, after external radiation therapy, is an excellent method to improve local control in the subset of patients with unexpectedly unsatisfactory margins.

Applications of brachytherapy in head and neck cancer

Brachytherapy offers the radiation oncologist the opportunity to deliver high doses of radiation to the tumor, with minimal doses to the surrounding normal tissue. This combination enhances the therapeutic ratio. It allows for enhanced tumor control, with minimal toxicity. When utilized, it often allows for tumor control without the need for resection. This is especially important in the head and neck. Resection of organs such as the lip, oral tongue, base-of-tongue, and other sites can cause significant functional and cosmetic morbidity. The ability to save these structures, using radiation therapy instead of surgery, can provide excellent tumor control and optimal quality-of-life outcome. In situations of recurrent disease, especially when prior radiation has been given, brachytherapy is often the only way to re-irradiate certain areas. This can be done alone, or in combination with surgery. Therefore, brachytherapy becomes an important component of the treatment of recurrent disease. This broad overview of the use of brachytherapy in head and neck cancer will include applications in the primary as well as the recurrent disease setting.

Radiosurgery for skull base malignancies and nasopharyngeal carcinoma

PURPOSE

Patients with skull base lesions present a challenging management problem because of intractable symptoms and limited therapeutic options. In 1989 we began treating selected patients with skull base lesions using linac stereotactic radiosurgery. In this study the efficacy and toxicity of this therapeutic modality is investigated.

METHODS AND MATERIALS

Forty-seven patients with 59 malignant skull base lesions were treated with linac radiosurgery between 1989 and 1995. Eleven patients were treated for primary nasopharyngeal carcinoma using radiosurgery as a boost (7 Gy-16 Gy, median: 12 Gy) to the nasopharynx after a course of fractionated radiotherapy (64.8-70 Gy) without chemotherapy. Another 37 patients were treated for 48 skull base metastases or local recurrences from primary head and neck cancers. Eight of these patients had 12 locally recurrent nasopharyngeal carcinoma lesions occuring 6-96 months after standard radiotherapy, including one patient with nasopharyngeal carcinoma who developed a regional relapse after radiotherapy with a stereotactic boost. Lesion volumes by CT or MRI ranged from 0 to 51 cc (median: 8 cc). Radiation doses of 7.0 Gy-35.0 Gy (median: 20.0 Gy) were delivered to recurrent lesions, usually as a single fraction.

RESULTS

All 11 patients who received radiosurgery as a nasopharyngeal boost after standard fractionated radiotherapy remain locally controlled (follow-up: 2-34 months, median: 18). However, one patient required a second radiosurgical treatment for regional relapse outside the initial radiosurgery volume. Thirty-three of 48 (69%) recurrent/metastatic lesions have been locally controlled, including 7 of 12 locally recurrent nasopharyngeal lesions. Follow-up for all patients with recurrent lesions ranged from 1 to 60 months (median: 9 months). Local control did not correlate with lesion size (p = 0.80), histology (p = 0.78), or radiosurgical dose (p = 0.44). Major complications developed after 5 of 59 treatments (8.4%), including three cranial nerve palsies, one CSF leak, and one trismus. Complications were not correlated with radiosurgical volume (p = 0.20), prior skull base irradiation (p = 0.90), or radiosurgery dose > 20 Gy (p = 0.49).

CONCLUSION

Stereotactic radiosurgery is a reasonable treatment modality for patients with skull base malignancies, including patients with primary and recurrent nasopharyngeal carcinoma. The dose distribution obtained with stereotactic radiosurgery provides better homogeneity than an intracavitary implant when used as a boost for nasopharyngeal lesions, especially lesions which involve areas distant to the nasopharyngeal mucosa.

Pilot study of intraoperative high dose rate brachytherapy for head and neck cancer

PURPOSE

To develop a new technique, intraoperative high dose rate brachytherapy (IOHDR), to deliver localized radiation therapy intraoperatively to head and neck tumors at sites inaccessible to intraoperative electron beam radiotherapy (IOEBRT) in the skull base region.

METHODS

After maximal surgical resection, afterloading catheters spaced 1 cm apart embedded in custom surface applicators made of foam or silicone were placed on resected tumor beds. IOHDR was delivered in a shielded operating room using preplanned dosimetry with a nominal 10 Ci iridium-192 source in an HDR micro-Selectron afterloader. Twenty-nine patients (20 males, 9 females) ranging in age from 9 to 80 years (median = 61) were irradiated intraoperatively for advanced head and neck tumors at sites inaccessible to IOEBRT. Six patients who had previously received external beam radiation (EBRT) ranging from 50 to 75 Gy, were given 15 Gy of IOHDR only. Twenty-three patients who had no prior radiation received 7.5 to 12.5 Gy IOHDR, and 45 to 50 Gy EBRT was planned post-operatively; however, six of these patients did not complete the planned EBRT. Doses to normal tissues were reduced whenever possible by shielding with lead or by displacement with gauze or retractors. Treatment time ranged from 3.8 to 23 min (median = 6.5 min). Five patients received concurrent cis-platinum based chemotherapy.

RESULTS

Twenty-nine patients treated to 30 sites had local tumor control of 67% and crade survival of 72%, with the follow-up ranging from 3 to 33 months (median = 21 months). In the group of 17 previously unirradiated patients who had completed full treatment (IOHDR and EBRT) to 18 sites, the local tumor control was 89%, and all of these patients survived. Tumor control in the six previously unirradiated patients who did not complete EBRT was 50% with a crude survival of 50%. In the group of six previously irradiated patients treated by IOHDR only, the local tumor control was 17% with a crude survival of 17%. No intraoperative complications were noted. The delayed morbidity included cerebrospinal fluid (CSF) leak with bone exposure (1), chronic subdural hematoma (1), septicemia (1), otitis media (1), and severe xerostomia (1). We cannot comment on long-term morbidity due to the relatively short follow-up period of 21 months.

CONCLUSIONS

It is feasible to deliver IOHDR, with acceptable toxicity, to skull base tumors at sites inaccessible to IOEBRT. The use of IOHDR as a pre-radiotherapy boost produced excellent local control and survival in the selected group of patients who had no previous radiation therapy. The use of exclusive IOHDR in the previously irradiated group resulted in poor outcome, possibly due to the limitations on re-irradiation doses and/or volumes determined by normal tissue tolerance or because these patients have inherently radioresistant tumors. Higher IOHDR doses, additional EBRT, and/or chemotherapy should be considered for this group. The use of IOHDR as a pre-EBRT boost to maximize local control has a promising future in the treatment of carefully selected patients with advanced skull base tumor.

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.

Radiosurgery for palliation of base of skull recurrences from head and neck cancers

BACKGROUND

Seven patients received stereotaxic radiosurgery for 10 lesions at the base of the skull (BOS) from recurrent head and neck malignant neoplasms.

METHODS

A radiation dose of 17.5-35.0 Gy was delivered as a single fraction. Follow-up ranged from 1 to 14 months.

RESULTS

Nine lesions were symptomatic, and the symptoms improved in five and stabilized in four lesions. In addition, a significant radiographic response was observed in 4 of 10 recurrences. Cranial nerve signs developed in two patients, and an area of asymptomatic necrosis developed in one patient in the temporal lobe tip.

CONCLUSIONS

From their brief experience, the authors conclude that stereotaxic radiosurgery may be a promising treatment in locally controlling recurrent head and neck cancers that involve the BOS.

New intraoperative brachytherapy techniques for positive or close surgical margins

Tumors attached or adjacent to critical structures can often not be completely resected or resected with adequate surgical margins. Sites involving major blood vessels, the paravertebral spaces, or critical abdominal structures often present technical difficulties for standard brachytherapy procedures using I-125 or Ir-192 implants. These techniques allow for a high-dose delivery to the tumor bed with minimal normal tissue toxicity. A relatively simple and accurate method is described using I-125 seeds in Vicryl suture threaded through Gelfoam. These permanent implant procedures with radioactive I-125 seeds effectively treat small residual tumors or suspicious margins where standard brachytherapy techniques may be unsatisfactory and technically difficult to perform.