The role of adjuvant external beam radiation therapy for papillary thyroid carcinoma invading the trachea

Propensity score matching analysis of adjuvant external-beam radiotherapy for the treatment of papillary thyroid carcinoma with other organ invasions

PURPOSE

The role of adjuvant external-beam radiotherapy (EBRT) in the treatment of locally advanced papillary thyroid carcinoma (PTC) remains controversial due to the lack of prospective data and the conflicting retrospective data. This study aimed to determine the benefits of adjuvant EBRT in patients with PTC and other organ invasions using propensity score matching to reduce the heterogeneity of the patient population.

METHODS

Data from patients with PTC with other organ invasions but no distant metastases who underwent surgery and adjuvant radioactive iodine (RAI) alone (Non-EBRT group) or adjuvant EBRT plus RAI (EBRT group) were retrospectively reviewed. Propensity matching was used to reduce heterogeneity. Survival outcomes and toxicities associated with EBRT were evaluated.

RESULTS

Between January 2005 and December 2019, 102 patients in the Non-EBRT group and 26 patients in the EBRT group were evaluated. In the 48 propensity score-matched patients, no significant differences in baseline characteristics between the Non-EBRT and EBRT groups were detected. The locoregional recurrence-free survival (LRRFS) and recurrence-free survival (RFS) rates were significantly higher in the EBRT group compared with the rates in the Non-EBRT group (5y-LRRFS: 100% vs. 74%, p = 0.003, 5y-RFS: 91% vs. 74%, p = 0.035). EBRT was well-tolerated, with no grade ≥ 3 toxicity, and all patients completed the therapy as planned.

CONCLUSION

Adjuvant EBRT plus RAI exhibited acceptable toxicity and improved LRRFS and RFS in patients with PTC with other organ invasions compared with RAI alone.

Postoperative external beam radiotherapy for locoregional control in iodine refractory differentiated thyroid cancer

Background

The role of postoperative external beam radiotherapy (EBRT) in patients with residual iodine refractory-differentiated thyroid cancer (IR-DTC) is still inconclusive. The aim of this retrospective study was to evaluate locoregional control (LRC) and overall survival (OS), and potential side effects after postoperative EBRT for both microscopic and macroscopic non-radically resected, locally advanced IR-DTC.

Methods

Between 1990 and 2016, 49 patients with locally advanced IR-DTC received EBRT for microscopic (R1; n = 28) or macroscopic (R2; n = 21) locoregional residual disease. For more insight into the added effect of EBRT, we performed an intrapatient sub-analysis in 32 patients who had undergone more than 1 surgical intervention, comparing LRC after primary, curative-intended surgery with LRC after repeated surgery plus EBRT. To estimate LRC and OS, we used Kaplan-Meier curves. From 2007 onward, we prospectively recorded toxicity data in our head and neck cancer database (n = 10).

Results

LRC rates 5 years after EBRT were higher for R1 (84.3%) than for R2 (44.9%) residual disease (P = 0.016). The 5-year OS rate after EBRT was 72.1% for R1 and 33.1% for R2 disease (P = 0.003). In the intrapatient analysis (n = 32), LRC rates were 6.3% 5 years after only initial surgery and 77.9% after repeated surgery with EBRT (P < 0.001). Acute toxicity was limited to grade I and II xerostomia, mucositis, and hoarseness; only one patient developed late grade III dysphagia.

Conclusions

Postoperative EBRT is associated with long-lasting LRC and OS with acceptable toxicity in patients with locally advanced IR-DTC, especially in microscopic residual disease.

Adjuvant radiotherapy and radioiodine treatment for locally advanced differentiated thyroid cancer: systematic review and meta-analysis

BACKGROUND

Treatment for locally advanced differentiated thyroid cancer is surgery followed by radioiodine while the role of adjuvant external beam radiotherapy (EBRT) is debated.

METHODS

The panel of the Italian Association of Radiotherapy and Clinical Oncology developed a clinical recommendation on the addition of EBRT to radioiodine after surgery for locally advanced differentiated thyroid cancer by using the Grades of Recommendation, Assessment, Development, and Evaluation methodology and the Evidence to Decision framework. A systematic review with meta-analysis about this topic was conducted with a focus on outcome of benefits and toxicity.

RESULTS

Locoregional control was improved by EBRT while no considerable toxicity impact was reported.

CONCLUSION

The panel judged uncertain the benefit/harms balance; final recommendation was conditional both for EBRT + radioiodine and radioiodine alone in the adjuvant setting.

Usefulness of a 3D-Printed Thyroid Cancer Phantom for Clinician to Patient Communication

BACKGROUND

Thyroid glands and surrounding structures are very complex, and this complexity can pose a challenge for clinicians when explaining and communicating to the patient the details of a proposed surgery for thyroid cancer. A three-dimensional (3D) thyroid cancer model could help and improve this communication.

METHODS

A 3D-printed phantom of a thyroid gland and its presenting cancer was produced from segmented head and neck contrast-enhanced computed tomography (CT) data from a patient with thyroid cancer. The phantom reflects the complex anatomy of the arteries, veins, nerves, and other surrounding organs, and the printing materials and techniques were adjusted to represent the texture and color of the actual structures. Using this phantom, patients and clinicians completed surveys on the usefulness of this 3D-printed thyroid cancer phantom.

PARTICIPANTS

patients (n = 33) and clinicians (n = 10).

RESULTS

In the patient survey, the patients communicated that the quality of understanding of their thyroid disease status was enhanced when clinicians explained using the phantom. The clinicians communicated that the 3D phantom was advantageous for explaining complex thyroid surgery procedures to patients, and that the 3D phantom was helpful in educating patients with relatively poor anatomical knowledge.

CONCLUSIONS

Using 3D printing technology, we produced a CT-based 3D thyroid cancer phantom, and patient and clinician surveys on its utility indicated that it successfully helped educate patients, providing them with an improved understanding of the disease.

The Role of postoperative external beam radiotherapy for differentiated thyroid carcinoma: A Systematic review and meta-analysis

The indications for external beam radiotherapy (RT) in differentiated thyroid carcinomas (DTC) are still undefined. The objective of this study was to synthesize current evidence defining the role of postoperative RT in patients with DTC. A systematic review and meta-analysis were done. Included studies compared oncologic outcomes and toxicity of RT vs no RT in patients with DTC. Nine studies were included, two prospective and seven retrospective cohorts. RT improved 5-year locoregional recurrence-free survival but not overall survival and distant metastasis failure-free survival. The locoregional control benefit was seen in patients at increased risk for recurrence, including those with advanced age, locoregionally advanced disease, gross or microscopic residual tumor, and structural invasion. Serious RT-related acute and late toxicities were rare. Available evidence suggests that postoperative RT can improve locoregional control in high-risk DTC with acceptable toxicity. Further prospective studies are warranted.

Secondary tracheal tumors: a systematic review

BACKGROUND

Secondary tracheal tumors arise from mural invasion by primary tumors in adjacent organs, metastatic lymph nodes or blood-born metastasis from distant sites. This systematic review aims to assess the presentation, management options, and clinical outcomes of these uncommon non-tracheal malignancies.

METHODS

Electronic searches of the MEDLINE database were performed to identify case series and individual case reports of tracheal invasion by primary non-tracheal tumors or metastatic disease. All English-language studies with available abstracts or articles containing primary data were included.

RESULTS

From 1978 to 2017, a total of 160 case reports or case series identified 2,242 patients with invasion of the trachea by tumors of adjacent organs (n=1,853) or by metastatic lymph nodes or hematogenous spread (n=389). Common primary sites of origin were thyroid, esophagus, and lung, and the most common presentation was metachronous (range of interval: 0 to 564 months) with dyspnea, neck mass, voice change and/or hemoptysis. A majority of patients in case reports (77.9%) and case series (66.0%) underwent resection and the most common reported operation was segmental tracheal resection. Fewer patients underwent bronchoscopic intervention (21.7%) and radiation was used in 32.2% of patients. Complications after bronchoscopic treatment included bleeding, granulation tissue, and retained secretions, while anastomotic leak, unplanned tracheostomy, and new recurrent laryngeal nerve paralysis were observed after surgical resection. The rate of 30-day mortality was low (0.01-1.80%). Median survival was higher in patients with thyroid malignancy and in patients who underwent surgical management. Follow-up time ranged from 0.03 to 183 months.

CONCLUSIONS

Patients with tracheal invasion by metastatic or primary non-tracheal malignancies should be assessed for symptoms, tumor grade, tumor recurrence and concurrent metastases to decide on optimal surgical, bronchoscopic or noninterventional therapy. Clinical experience suggests that palliative endoscopic intervention for tracheal obstruction by metastasis-bearing lymph nodes is underreported.