The American College of Radiology and the American Brachytherapy Society practice parameter for the performance of low-dose-rate brachytherapy

Safety and efficacy of CT-guided radioactive iodine-125 seed implantation as a salvage treatment for recurrent head and neck cancer after two or more courses of radiotherapy

BACKGROUND

In the past, patients with recurrent head and neck cancer (rHNC) who had previously received a high dose of radiation and were unable to undergo surgery were mainly treated with palliative chemotherapy due to the high incidence of side effects from re-irradiation. With the development of radiotherapy technology, re-irradiation of recurrent lesions by radioactive iodine-125 seed implantation (RISI) has been proposed as a feasible therapeutic approach. This study aimed to investigate the safety and efficacy of computed tomography (CT)-guided RISI in the treatment of rHNC after two or more courses of radiotherapy, and to analyze the prognostic factors.

METHODS

Data of 33 patients with rHNC who received CT-guided RISI after two or more courses of radiotherapy were collected and statistically analyzed. The median cumulative dose of the previous radiotherapy was 110 Gy. Short-term efficacy was assessed by Response Evaluation Criteria in Solid Tumors (version 1.1) criteria, while adverse events were evaluated by Common Terminology Criteria for Adverse Events (version 5.0) criteria.

RESULTS

The median gross tumor volume (GTV) was 29.5 cc, and the postoperative median dose to 90% of target volume (D90) was 136.8 Gy. For adverse reactions, enhanced pain was found in 3 (9.1%) patients, followed by grade 1 to 2 acute skin reactions in 3 (9.1%) patients, grade 2 to 3 late skin reactions in 2 (6.1%) patients, grade 1 to 2 early mucosal reactions in 4 (12.1%) patients, and mandibular osteonecrosis in 1 (3.0%) patient. Regarding the treatment efficacy, the 1- and 2-year local control (LC) rates were 47.8% and 36.4% (median LC time, 10 months), and the 1- and 2-year overall survival (OS) rates were 41.3% and 32.2% (median OS time, 8 months). The absence of adverse events was associated with better LC.

CONCLUSIONS

CT-guided RISI, as a salvage therapy, demonstrated acceptable safety and efficacy in the treatment of rHNC after two or more courses of radiotherapy.

TRIAL REGISTRATION

This study was registered at Chinese Clinical Trial Register database (Registration No. ChiCTR2200063261 ) in September 2, 2022.

Current radiotherapy for recurrent head and neck cancer in the modern era: a state-of-the-art review

BACKGROUND

In the management of head and neck cancer (HNC) patients, local recurrence is a common cause of treatment failure. Only a few patients with recurrent HNC (rHNC) are eligible for salvage surgery and the majority of patients receive systemic therapy and radiotherapy. In recent years, with the development of irradiation technology, radiotherapy for rHNC patients has markedly attracted clinicians' attention and its therapeutic effects on patients with end-stage cancer are worthy of investigation as well.

METHODS

Several studies have investigated the role of radiotherapy in the treatment of rHNC patients. We reviewed retrospective reports and prospective trials published in recent decades that concentrated on the management of rHNC.

RESULTS

A growing body of evidence supported the application of irradiation to rHNC patients. According to the results of this review, current radiotherapy could achieve a better efficacy with a lower incidence of toxicity.

CONCLUSION

Radiotherapy is a promising treatment for rHNC patients.

High dose rate192Ir versus high dose rate60Co brachytherapy: an overview of systematic reviews of clinical responses of gynecological cancers from 1984 to 2020

The Purpose. Radioisotope of192Iradium (192Ir) has a half-life (74 days) and is not easily accessible in developing countries. As a result, by the time source shipment clearance and the customs paperwork are completed, a large proportion of useful activity had already been decayed away. In fact,60Cobalt (60Co) remote afterloading systems are commercially available by many venders. As a result, it may well become an alternative source to192Ir and conform many of these challenges. The aim of this study is that to report clinical responses of different types of gynaecological cancers treated with high dose rate (HDR)192Ir and HDR60Co brachytherapy in order to check whether HDR60Co could be used as an alternative brachytherapy, source to HDR192Ir.Materials and Methods. A retrospective study of clinical responses of different types of gynaecological cancers, staged from I to IV according to recommendations of International Federation of Gynaecology and Obstetrics (FIGO), treated by brachytherapy alone, radiotherapy alone (combined brachytherapy and radiotherapy) and combined radiotherapy and chemotherapy (brachytherapy, radiotherapy and chemotherapy) between 1984 and December 2020 was conducted. The patients were treated with external beam radiotherapy 45-51 Gy boosted with HDR192Ir and HDR60Co afterloading brachytherapy of 18-30 Gy to point A.The results. The study scrutinized the data of 11086 patients with different types of gynaecological cancers. Most of the patients, 70 percent of them, were diagnosed with gynaecological cancers in stages II and III. For patients treated with192Ir brachytherapy source 5-years overall survival rate (OS), local control, 2-years, 5-years and 10-years disease free survival (DFS), complications of gastro-intestine (GI) and complications of genito-urinary (GU) were 63.5%, 92%, 72.6%, 64.07%, 43.75%, 3.9% and 5.92%, but for those treated with60Co they were 57.7%, 86.63%, 82.5%, 53.35%, 43.75%, 4.8% and 3.7%, respectively.Conclusions.The use of HDR60Co brachytherapy has the capacity to produce overall survival rate and disease control in patients with carcinoma of the gynaecology comparable to that reported for HDR192Ir brachytherapy. Currently, the toxicity and damage of the normal tissues and radiation-related second cancers are of a similar incidence to that of standard HDR192Ir brachytherapy. Source exchange frequency is not a serious concern because it requires less frequency of replacement, and commissioning can be accomplished within years; hence, replacing HDR192Ir with HDR60Co brachytherapy achieves significant cost saving. Therefore, we recommend that60Co source ought to be the first choice for low resource radiotherapy setting as it offers economic advantages over192Ir and have comparable clinical outcomes to that of192Ir source.

Interobserver variability of 3.0-tesla and 1.5-tesla magnetic resonance imaging/computed tomography fusion image-based post-implant dosimetry of prostate brachytherapy

This study aimed to compare the interobserver variabilities in magnetic resonance imaging (MRI)/computed tomography (CT) fusion image-based post-implant dosimetry of permanent prostate brachytherapy (PPB) between 1.5-T and 3.0-T MRI. The study included 60 patients. Of these patients, 30 underwent 1.5-T MRI and CT 30 days after seed implantation (1.5-T group), and 30 underwent 3.0-T MRI and CT 30 days after seed implantation (3.0-T group). All patients received PPB alone. Two radiation oncologists performed MRI/CT fusion image-based post-implant dosimetry, and the interobserver variabilities of dose-volume histogram (DVH) parameters [dose (Gy) received by 90% of the prostate volume (prostate D90)], percentage of the prostate volume receiving at least the full prescribed dose (prostate V100), percentage of the prostate volume receiving at least 150% of the prescribed dose (prostate V150), dose (Gy) received by 5% of the urethral volume (urethral D5) and the urethral volume receiving at least 150% of the prescribed dose (urethral V150)] were retrospectively estimated using the paired Student's t test and Pearson's correlation coefficient. The Pearson's correlation coefficients of all DVH parameters were higher in the 3.0-T group than in the 1.5-T group (1.5-T vs 3.0-T: prostate D90, 0.65 vs 0.93; prostate V100, 0.62 vs 0.82; prostate V150, 0.97 vs 0.98; urethral D5, 0.92 vs 0.93; and urethral V150, 0.88 vs 0.93). In the paired Student's t test, no significant differences were observed in any of the DVH parameters between the two radiation oncologists in the 3.0-T group (0.068 ≤ P ≤ 0.842); however, significant differences were observed in prostate D90 (P = 0.004), prostate V100 (P = 0.011) and prostate V150 (P = 0.002) between the oncologists in the 1.5-T group. The interobserver variability of DVH parameters in the MRI/CT fusion image-based post-implant dosimetry analysis of brachytherapy was lower with 3.0-T MRI than with 1.5-T MRI.

Current status of brachytherapy in cancer treatment - short overview

Cancer incidence and mortality depend on a number of factors, including age, socio-economic status and geographical location, and its prevalence is growing around the world. Most of cancer treatments include external beam radiotherapy or brachytherapy. Brachytherapy, a type of radiotherapy with energy from radionuclides inserted directly into the tumor, is increasingly used in cancer treatment. For cervical and skin cancers, it has become a standard therapy for more than 100 years as well as an important part of the treatment guidelines for other malignancies, including head and neck, skin, breast, and prostate cancers. Compared to external beam radiotherapy, brachytherapy has the potential to deliver an ablative radiation dose over a short period of time directly to the altered tissue area with the advantage of a rapid fall-off in dose, and consequently, sparing of adjacent organs. As a result, the patient is able to complete the treatment earlier, and the risks of occurrence of another cancer are lower than in conventional radiotherapy treatment. Brachytherapy has increased its use as a radical or palliative treatment, and become more advanced with the spread of pulsed-dose-rate and high-dose-rate afterloading machines; the use of new 3D/4D planning systems has additionally improved the quality of the treatment. The aim of the present study was to present short summaries of current studies on brachytherapy for the most frequently diagnosed tumors. Data presented in this manuscript should help especially young physicians or physicists to explore and introduce brachytherapy in cancer treatments.

Punctate Radiation Dermatitis of the Foot and Ankle Caused by Distal Embolization of 90Y Microspheres During Liver Directed Therapy

A 41-year-old man with gastric adenocarcinoma presented with hepatic metastases. The metastases were refractory to systemic chemotherapy, so radioembolization with Y microspheres was performed. Because of stasis or saturation of the tumor with embolic particles, 79% of the microspheres were injected. At follow-up, the patient complained of "red bumps" that had developed on his right foot/ankle the day after the radioembolization. Because a portion of the dose was still in the catheter when withdrawn from the right femoral artery, the interventional radiologist used a Geiger counter to confirm radioactivity in the cutaneous lesions and thus the distal embolization of the microspheres.