Treatment of upper gum carcinoma with high-dose-rate customized-mold brachytherapy

High-dose-rate intraluminal brachytherapy for paraneoplastic autoimmune multiorgan syndrome

Paraneoplastic autoimmune multiorgan syndrome (PAMS), also known as paraneoplasic pemphigus, involves the skin, internal organs and mucosa. PAMS-associated mortality may occur as a result of autoantibody formation against internal tumors and their infiltration into organs other than the skin lesions that characterize PAMS. The most common symptoms of PAMS include pain associated with continuous oral ulceration and resistance to pharmacological treatment. The present study reports the case of a 42-year-old female patient who was admitted with an 8-month history of erosive skin lesions within the trunk region, oral mucosa and vaginal mucosa. The patient was diagnosed with PAMS based on computed tomography scans and histological analyses of the lesions. The lymphoid hyperplasia in the retroperitoneum and lesions in the vaginal mucosa and trunk area were improved following pharmacological treatment and resection of the lymph node showing hyperplasia. However, the oral lesion was treated with intraluminal brachytherapy due to its resistance to long-term pharmacological treatment. The majority of the lesions were improved following treatment, in the absence of any severe side effects. In addition, neither worsening nor progression of the oral lesion was observed during the 4-year follow-up period.

Review of advanced catheter technologies in radiation oncology brachytherapy procedures

The development of new catheter and applicator technologies in recent years has significantly improved treatment accuracy, efficiency, and outcomes in brachytherapy. In this paper, we review these advances, focusing on the performance of catheter imaging and reconstruction techniques in brachytherapy procedures using magnetic resonance images and electromagnetic tracking. The accuracy of catheter reconstruction, imaging artifacts, and other notable properties of plastic and titanium applicators in gynecologic treatments are reviewed. The accuracy, noise performance, and limitations of electromagnetic tracking for catheter reconstruction are discussed. Several newly developed applicators for accelerated partial breast irradiation and gynecologic treatments are also reviewed. New hypofractionated high dose rate treatment schemes in prostate cancer and accelerated partial breast irradiation are presented.

High-dose-rate brachytherapy using molds for lip and oral cavity tumors

Background

High-dose-rate (HDR) brachytherapy using the mold technique is a less invasive treatment for early lip and oral cavity cancer. However, limited reports exist regarding the feasibility of this method. In this retrospective study, we evaluated the outcome of this therapy and investigated its feasibility for lip and oral cavity tumors.

Methods

Between May 2002 and December 2010, 17 patients (median age, 80.0 years) with histologically confirmed squamous cell carcinoma of the lip or oral cavity were treated by means of HDR brachytherapy using the mold technique after external beam radiotherapy (EBRT). Tumor sites included the buccal mucosa in eight cases, the gingiva in three cases, the lips in two cases, the floor of the mouth in two cases, and the hard palate in two cases. For all patients, EBRT (30 Gy/15 fractions), was performed before HDR brachytherapy. Two 6-Gy fractions were delivered twice daily for 2 days a week with an interval of 6 hours between the fractions. The total HDR brachytherapy dose was 24 Gy. Prior to EBRT, two patients with neck metastasis underwent neck dissection, and one patient with an exophytic tumor underwent tumor resection.

Results

The median follow-up period was 53.4 (range, 4.8–83.4) months. Of the 17 patients, 14 (82.4%) achieved a complete response, and three (17.6%) displayed a partial response.

The overall 3- and 5-year survival rates were both 68.8%, the 3- and 5-year disease-specific survival rates were both 86.7%, and the 3- and 5-year local control rates were both 54.1%. Seven patients developed local recurrence at a median time of 3.4 (range, 1.7–29.1) months after treatment. Nodal and lung metastases occurred separately in two patients. By the end of the follow-up period, two patients had died of the primary disease and four patients had died of other causes.

Conclusions

Although there is a need to improve the technical aspects of the treatment protocol, HDR brachytherapy using the mold technique might be a therapeutic option for superficial lip or oral cavity tumors, especially in older patients who have a poor performance status or are in poor physical condition.

Endoscopy-guided brachytherapy for sinonasal and nasopharyngeal recurrences

OBJECTIVE/PURPOSE

To evaluate the preliminary results of perioperative endoscopy-guided brachytherapy (BT) in recurrent sinonasal and nasopharyngeal tumors already treated for their primary tumor with a full course of radiotherapy.

METHODS AND MATERIALS

Patients with recurrence and already treated with a previous full course of radiotherapy >65 Gy who underwent BT from December 2010 to January 2014 were taken into account for this work. Macroscopic disease was resected by an endoscopic approach, and catheters for BT were endoscopically positioned and fixed at the same time on the surgical bed. Surgery was performed under electromagnetic navigation guidance. The irradiation dose was 30 Gy in 12 fractions, 2.5 Gy each, twice a day, in 6 days.

RESULTS

We performed the endoscopy-guided BT 11 times in 9 patients; in two cases, no previous radiation therapy had been performed; and in one case, followup was too short to be considered. A total of 6 patients were eligible for the analysis. One patient underwent BT three times because of previous target margin recurrences. There were no immediate complications. The median and mean followups were 21 and 19 months, respectively. The median V90 and V85% were 93% and 95%, respectively. In one case, we had a transient deficit of the VI cranial nerve (G3), and in another case, we diagnosed a noncomplicated osteonecrosis (G2). The median disease-free survival is 12 months, and the median overall survival is 23 months.

CONCLUSIONS

The combination of endoscopy and BT seems to be a safe option for treating recurrent sinonasal and nasopharyngeal tumors.

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.

Locally advanced verrucous carcinoma of the oral cavity: treatment using customized mold HDR brachytherapy instead of hemi-maxillectomy

BACKGROUND

Oral verrucous carcinomas are locally invasive but rarely metastasize. Current treatment options include surgery and external beam radiotherapy (EBRT). In medical inoperable patients or irresectable tumors, high-dose-rate (HDR) brachytherapy is a valid alternative.

CASE

We present an 85-year-old man with functionally irresectable cT3N0M0 verrucous carcinoma superficially spreading along the upper alveolar ridge to the retro-alveolar triangle, with infiltration of the left soft and hard palate and buccal mucosa. Using a customized intraoral mold, this patient was treated with HDR brachytherapy delivering a dose of 48 Gy in 12 fractions three times per week. Treatment was well tolerated, and after prolonged confluent mucositis the tumor is in complete remission.

REVIEW OF LITERATURE AND CONCLUSION

The scarce literature on customized mold HDR brachytherapy in maxillary tumors is reviewed and recommendations for other head and neck tumors are given.

Shielding effect of a customized intraoral mold including lead material in high-dose-rate 192-Ir brachytherapy for oral cavity cancer

A high-dose-rate (HDR) 192-Ir brachytherapy using a customized intraoral mold is effective for superficial oral cavity cancer, and the surrounding normal tissue is kept away from the radioactive source with gauze pads and/or mouth piece for reducing the dose on the normal tissues. In the Tokushima university hospital, the mold has a lead shield which utilizes the space prepared with sufficient border-molding by a specific dental technique using modeling compound. In HDR 192-Ir brachytherapy using a lead shielded customized intraoral mold, there are no reports measuring the absorbed dose. The purpose of the present study is to measure the absorbed dose and discuss the optimum thickness of lead in HDR 192-Ir brachytherapy using a customized intraoral mold with lead shield using a 1 cm thickness mimic mold. The thickness of lead in the mold could be changed by varying the arrangement of 0.1 cm thickness sheet of the acrylic resin plate and lead. The measured doses at the lateral surface of the mold with thermo-luminescence dosimeter were reduced to 1.12, 0.79, 0.57, 0.41, 0.31, 0.24 and 0.19 Gy and the ratios to the prescription dose were reduced to 56, 40, 29, 21, 16, 12 and 10 percent as lead thickness increased from 0 to 0.6 cm in 0.1 cm increments, respectively. A 0.3 cm thickness lead was considered to be required for a 1 cm thickness mold, and it was necessary to thicken the lead as much as possible with the constraint of limited space in the oral cavity, especially at the fornix vestibule.

Two-piece customized mold technique for high-dose-rate brachytherapy on cancers of the buccal mucosa and lip

OBJECTIVE

High-dose-rate (HDR) brachytherapy using a customized mold is a minimally invasive treatment for oral cancer; however, it is difficult to use this technique for buccal and lip cancers involving the commissura labiorum, owing to its anatomic form. The purpose of this study was to introduce an improved customized mold consisting of 2 pieces to allow the fixation of molds to these sites.

STUDY DESIGN

Five patients with buccal carcinoma and 1 patient with lip carcinoma were treated with this technique after external beam radiotherapy. One patient with neck metastasis underwent both neck dissection and partial tumor resection before HDR brachytherapy.

RESULTS

At the end of the follow-up period, 5 patients had no tumor recurrence, and 1 patient had suffered local recurrence.

CONCLUSIONS

Our technique is a viable therapeutic option for patients with buccal and lip carcinomas for whom the therapeutic modalities are limited by age, performance status, and other factors.

Use of megavoltage computed tomography with image registration for high-dose rate treatment planning of an oral tongue cancer using a custom oral mold applicator with embedded lead shielding

PURPOSE

A patient with a lateral oral tongue cancer was treated with high-dose rate brachytherapy using an oral applicator with embedded lead shielding making conventional simulation, using either kilovoltage computed tomography or radiographs, impossible because of scatter artifact.

METHODS AND MATERIALS

Treatment simulation was accomplished using megavoltage computed tomography (MVCT) simulation on a helical tomotherapy unit. Because of difficulty in visualization of the catheters on the patient MVCT images, Velocity AI image registration software (Velocity Medical Solutions, Atlanta, GA) was used to register an MVCT of the applicator itself with the patient MVCT simulation. The treatment plan was manually optimized to prescribe 4Gy/fraction to the gross tumor volume.

RESULTS

The patient tolerated the treatment well, with no evidence of disease 6 months after treatment. Thermoluminescent dosimeter measurements showed that the shielding reduced the dose by up to 90%, depending on the location of the thermoluminescent dosimeter. While the patient was treated using dose distributions calculated in a homogeneous medium (Task Group-43), an approximation of the true dose distributions was retrospectively calculated using Acuros (Varian Medical Systems Inc., Palo Alto, CA), which accounts for heterogeneities in the patient.

DISCUSSION

Use of the MVCT with image registration allowed treatment planning in the presence of lead shielding. Dose-volume histograms showed that recalculation of the dose using heterogeneity correction did not affect the dose to the gross tumor volume, but that the dose to normal structures (maxilla and mandible) was reduced by the lead shielding.

CONCLUSION

The use of MVCT and image registration allows for optimized planning in the presence of shielding, which would not be possible with conventional kilovoltage computed tomography.

Use of customized-mold brachytherapy in the management of malignancies arising in the maxillary antrum after maxillectomy: a dosimetric analysis

PURPOSE

To explore the feasibility of a intraoral mold high-dose rate (HDR) brachytherapy in the treatment of tumors arising in the maxillary antrum after maxillectomy and to describe the dosimetric profile of HDR brachytherapy in such an unusual location.

METHODS AND MATERIALS

A customized mold with four 6-French catheters was designed and produced in transparent acrylic resin. The catheters formed a soft loop that allowed the passage of the HDR source. CT-based dose evaluation in several volumes of interest, including the gross tumor volume (GTV) and several organs at risk (OARs), such as the skin of the cheek, eyeball, lens, optic nerve, optic chiasm, and spinal cord was performed.

RESULTS

Treatments were delivered uneventfully. A favorable OAR/GTV ratio was observed. The GTV D(90) was covered by the 3.8 Gy isodose (95% of the prescription isodose of 4 Gy) and the doses received by the OARs varied between 4% and 43% of the prescription isodose for the V1 cc of spinal cord and eyeball, respectively. The only structure that could not be adequately spared was the skin overlying the tumoral lesion that received between 94% and 107% of the prescription isodose (1.0 and 0.5 cm(2) of skin, respectively).

CONCLUSIONS

Intraoral mold-based HDR brachytherapy can be used to treat tumors involving the maxillary antrum provided that access is possible through a previous maxillectomy. A dose reduction of 4-43% in several OARs, such as the spinal cord, pituitary gland, optic chiasm, optic nerve, eyeball, and lens, is obtained.

High-dose-rate brachytherapy for patients with maxillary gingival carcinoma using a novel customized intraoral mold technique

OBJECTIVE

The purpose of this study was to introduce a novel customized intraoral mold treatment for maxillary gingival carcinoma (UGC).

STUDY DESIGN

Two patients with UGC were treated as salvage therapy using this technique. The mold was designed to keep normal soft tissues adjacent to the tumor away from the radioactive source as much as possible, and it was shielded by lead. The radiation dose on the buccal mucosa and tongue was measured at the inner and outer surfaces of the intraoral mold before starting high-dose-rate brachytherapy by the remote afterloading system, and was reduced to almost one tenth.

RESULTS

The patient had no recurrence and no severe adverse effects on the normal soft tissue adjacent to the tumor until the end of the follow-up period.

CONCLUSION

High-dose-rate brachytherapy using the novel customized intraoral mold might be a treatment option of not only salvage therapy, but definitive therapy of UGC.