A prospective longitudinal study on endocrine dysfunction following treatment of laryngeal or hypopharyngeal carcinoma

Incidence and complications of hypothyroidism postlaryngectomy: A systematic review and meta-analysis

BACKGROUND

Hypothyroidism is common postlaryngectomy and is associated with laryngectomy-specific complications. The objective of this study is to determine the incidence and predictors of hypothyroidism postlaryngectomy and its associated complications.

METHODS

Systematic review, data extraction, and meta-analyses were performed following the PRISMA protocol. Six databases were searched for studies reporting on postlaryngectomy thyroid status with incidence, risk factors, management, or complications.

RESULTS

Fifty-one studies with 6333 patients were included. The pooled incidence of postlaryngectomy hypothyroidism is 49% (CI 42%-57%). Subgroup analysis showed postlaryngectomy hypothyroidism rates significantly correlated with hemithyroidectomy and radiotherapy. Patients who underwent laryngectomy, hemithyroidectomy, and radiotherapy had a 65% (CI 59%-71%) rate of hypothyroidism; laryngectomy and hemithyroidectomy 46% (CI 33%-60%); laryngectomy and radiotherapy 26% (CI 19%-35%); and laryngectomy alone 11% (CI 4%-27%) (p < 0.001).

CONCLUSIONS

Laryngectomized patients with partial thyroidectomy or radiation therapy are at significant risk of postoperative hypothyroidism. Evidence-based protocols for early detection and (prophylactic) treatment should be established.

Development and validation of a machine learning model of radiation-induced hypothyroidism with clinical and dose-volume features

BACKGROUND AND PURPOSE

Radiation-induced hypothyroidism (RIHT) is a common but underestimated late effect in head and neck cancers. However, no consensus exists regarding risk prediction or dose constraints in RIHT. We aimed to develop a machine learning model for the accurate risk prediction of RIHT based on clinical and dose-volume features and to evaluate its performance internally and externally.

MATERIALS AND METHODS

We retrospectively searched two institutions for patients aged >20 years treated with definitive radiotherapy for nasopharyngeal or oropharyngeal cancer, and extracted their clinical information and dose-volume features. One was designated the developmental cohort, the other as the external validation cohort. We compared the performances of machine learning models with those of published normal tissue complication probability (NTCP) models.

RESULTS

The developmental and external validation cohorts consisted of 378 and 49 patients, respectively. The estimated cumulative incidence rates of grade ≥1 hypothyroidism were 53.5% and 61.3% in the developmental and external validation cohorts, respectively. Machine learning models outperformed traditional NTCP models by having lower Brier scores at every time point and a lower integrated Brier score, while demonstrating a comparable calibration index and mean area under the curve. Even simplified machine learning models using only thyroid features performed better than did traditional NTCP algorithms. The machine learning models showed consistent performance between folds. The performance in a previously unseen external validation cohort was comparable to that of the cross-validation.

CONCLUSIONS

Our model outperformed traditional NTCP models, with additional capabilities of predicting the RIHT risk at individual time points. A simplified model using only thyroid dose-volume features still outperforms traditional NTCP models and can be incorporated into future treatment planning systems for biological optimization.

Incidence of Post Total Laryngectomy Hypothyroidism: Effects of Thyroid Gland Surgery and Post-Operative Radiotherapy

To record the incidence of hypothyroidism in patients after total laryngectomy, whether with or without postoperative radiation therapy and to analyze the effect of hemithyroidectomy for the development of hypothyroidism. A retrospective study included patients who underwent total laryngectomy (with or without hemithyroidectomy) between 2018 and 2021 for laryngeal carcinoma and/or received postoperative radiotherapy. Thirty-six (45%) of the 80 enrolled patients developed hypothyroidism after a median follow-up of 16 months. In this study, adjuvant radiation and central neck dissection were found to be significantly linked with developing post-operative hypothyroidism (p values: 0.001, 0.007, respectively). The incidence of hypothyroidism in patients treated for laryngeal carcinoma is high, especially after combination treatment of surgery and radiotherapy.

Central Compartment Neck Dissection in Laryngeal and Hypopharyngeal Squamous Cell Carcinoma: Clinical Considerations

Metastatic lymph node involvement represents the most relevant prognostic factor in head and neck squamous cell carcinomas (HNSCCs), invariably affecting overall survival, disease-specific survival, and relapse-free survival. Among HNSCCs, laryngeal and hypopharyngeal cancers are known to be at highest risk to metastasize to the central neck compartment (CNC). However, prevalence and prognostic implications related to the CNC involvement are not well defined yet, and controversies still exist regarding the occult metastasis rate. Guidelines for the management of CNC in laryngeal and hypopharyngeal cancers are vague, resulting in highly variable selection criteria for the central neck dissection among different surgeons and institutions. With this review, the authors intend to reappraise the existing data related to the involvement of CNC in laryngeal and hypopharyngeal malignancies, in the attempt to define the principles of management while highlighting the debated aspects that are lacking in evidence and consensus. Furthermore, as definition and boundaries of the CNC have changed over the years, an up-to-date anatomical-surgical description of the CNC is provided.

The use of near-infrared autofluorescence during total laryngectomy with hemi- or total thyroidectomy

PURPOSE

The aim of this study is to describe the use of near-infrared autofluorescence (NIR-AF) to identify and preserve parathyroid glands (PGs) in a group of patients with advanced hypopharyngeal/laryngeal cancer undergone total (pharyngo)laryngectomy with hemi- or total thyroidectomy.

METHODS

At San Raffaele Hospital, Milan (Italy), from January 2021 to May 2021, 7 patients affected by cT4a laryngeal squamous cell carcinoma (SCC) underwent surgery using an autofluorescence detection system (Fluobeam-Fluoptics^®). For proper surgical planning, the demolition phase envisaged extension of the intervention to 4 hemithyroidectomies and 3 total thyroidectomies associated, respectively, with homolateral or bilateral CCND. Serum calcium, ionized calcium, and parathyroid hormone (PTH) levels at post-operative day (POD) 1 and 2 and at 2 weeks after surgery were monitored. Finally, we compared the data obtained with a cohort of patients who underwent surgery without the adoption of NIR-AF.

RESULTS

With the use of NIR-AF, 18/20 PGs were identified, of which 7/18 were preserved exclusively thanks to the use of autoflorescence. The technique also made it possible to identify and isolate three PGs from the surgical specimen, which were subsequently transplanted only after intraoperative histological confirmation. On POD-1, 3/7 patients (42.8%) were hypocalcemic; on POD-2 and after 2 weeks only 1/7 patient (14.2%) was hypocalcemic. Comparing the two groups, we highlighted that the utilization of NIR-AF was related to a significant decrease of median serum (p = 0.026) and ionized calcium levels (p = 0.017) 2 weeks after surgery. Using this new technology, in no case did definitive histological examination reveal the presence of PGs in the surgical specimen, reaching an accuracy of 100%.

CONCLUSIONS

In our cohort of patients who underwent total (pharyngo)laryngectomy with hemi- or total thyroidectomy, the use of near-infrared autofluorescence improved medium term postoperative hypocalcemia rates. This new technology helps to achieve a better calcemic outcome compared to the standard naked eye approach, since it helps the surgeon to identify and preserve parathyroid glandular tissue with a lower incidence of post-operative hypocalcemia.

Paratracheal lymph node dissection during total (pharyngo-)laryngectomy: A systematic review and meta-analysis

OBJECTIVES

The objective of this review was to determine the rate and risk factors of paratracheal lymph node (PTLN) involvement during total laryngectomy (TL) or total pharyngolaryngectomy (TPL). In addition, we aimed to assess its prognostic significance in terms of survival and peristomal recurrence.

METHODS

A comprehensive electronic search was performed on PubMed, EMBASE, and CENTRAL databases. We searched for studies reporting outcomes of PTLN dissection during radical laryngeal surgery for squamous cell carcinoma of the larynx, hypopharynx or cervical oesophagus.

RESULTS

We included a total of ten studies (838 patients). The overall rate of PTLN dissection positivity was 18.6% (20.7% for primary TL, 8.7% for salvage TL). Random-effects meta-analysis identified T4 stage, N+ stage of the lateral neck, subglottis involvement and primary tumour arising from the hypopharynx or cervical oesophagus as significant risk factors for PTLN involvement.

CONCLUSIONS

This meta-analysis allowed to better define the risk of PTLN involvement during TL or TPL, in a bid to guide indication for PTLN dissection. There is a need for further large studies reporting rigorously the outcomes of PTLN dissection in order to establish stronger evidence-based recommendations.

Routine thyroidectomy with total laryngectomy: Is it really indicated? A randomized controlled trial

Background

We investigated the incidence of thyroid gland invasion in patients with advanced laryngeal carcinoma who were treated with total laryngectomy, also the impact of different preoperative and intraoperative predictors on thyroid gland invasion. Moreover, the impact of thyroid gland preservation on the locoregional tumor control and the recurrence rates after surgery were investigated.

Materials and methods

This study was conducted over 5 years on 100 patients with advanced laryngeal carcinoma who underwent total laryngectomy. The adopted protocol in our hospital is to perform an ipsilateral thyroid lobectomy if there is subglottic extension, thyroid or cricoid cartilage invasion or true invasion of the thyroid gland. The patients of the study were divided into thyroid sparing and thyroid sacrificing groups. The two groups were compared in terms of demographic data, tumor characteristics, incidence of postoperative hypothyroidism and tumor recurrence.

Results

There was no significant difference between groups regarding the tumor profile. Regarding local tumor spread, the only two subsites that showed significant difference is anterior commissure and thyroid cartilage invasion. In the thyroid sacrificing group, invasion of the thyroid gland was proved histopathologically in only one patient. Postoperatively, the incidence of hypothyroidism was significantly higher in the thyroid sacrificing group. However, there was no statistically significant difference between the two groups regarding the incidence of tumor recurrence.

Conclusion

The incidence of thyroid gland invasion by an advanced laryngeal carcinoma is low. Preservation of the thyroid gland during laryngectomy to reduce the risk of thyroid dysfunction does not affect the oncological control.

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Thyroid gland invasion incidence in advanced laryngeal carcinoma is low.

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Thyroid gland Preservation during laryngectomy does not affect the oncological control.

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There was no statistically significant difference between the thyroid sparing and thyroid sacrificing group regarding the incidence of recurrence. Due toding author”. Due toding author".

Hypocalcaemia in pharyngolaryngectomy: Preservation or autotransplantation of parathyroid glands

OBJECTIVE

To describe transient and permanent hypocalcaemia following partial and total pharyngolaryngectomy with parathyroid gland preservation or autotransplantation.

METHODS

Thirty patients underwent partial or total pharyngolaryngectomy by a single surgeon during the period 2009-2020. Intraoperative parathyroid gland preservation or autotransplantation (where the gland appeared devascularized) was routinely performed. Calcium levels performed on day 1, 3 months, and at 12 months postoperatively were collected. Rates of transient and permanent hypocalcaemia were calculated.

RESULTS

A total of 13% of patients had transient hypocalcaemia, and 10% permanent hypocalcaemia. Rates of transient and permanent hypocalcaemia in total pharyngolaryngectomy were 14% and 14%, respectively. Partial pharyngectomy hypocalcaemia rates were 13% for transient and 0% for permanent. The majority of patients underwent salvage surgery for oncological resection, often following radiotherapy (63%). Ipsilateral hemithyroidectomy was preferred to total (57% vs 7%), with high rates of concurrent neck dissection (67%) and reconstruction (87%).

CONCLUSION

This data supports preservation or autotransplantation of parathyroid glands as a means of reducing permanent postoperative hypocalcaemia.

LEVEL OF EVIDENCE

Level IV, case series, retrospective.

The incidence of thyroid gland invasion in advanced laryngeal squamous cell carcinoma

Introduction

Invasion of the thyroid gland is not a general feature of advanced laryngeal carcinoma. There is no need for performing thyroidectomy in all total laryngectomy cases.

Objectives

To evaluate the frequency of the thyroid gland invasion in patients with advanced laryngeal squamous cell carcinoma submitted to total laryngectomy and thyroidectomy and to determine whether clinical and pathological characteristics of laryngeal carcinoma can predict glandular involvement.

Methods

A retrospective case series with chart review, from March 2009 to January 2018, was undertaken in the the Princess Norah Oncology Center, King Abdul-Aziz Medical City, Jeddah/KSA. An inception cohort of 56 patients with laryngeal squamous cell carcinoma was considered. Nine cases were excluded. All patients had advanced stage cancer of the larynx (clinically T3‒T4) and underwent total laryngectomy in association with thyroidectomy. Total thyroidectomy was performed in all bilateral lesions or if there was suspicion of contralateral lobe involvement. Hemithyroidectomy was performed in all lateralized lesions. Retrospective histopathologic analysis of thyroid specimens was subsequently performed. The frequency of thyroid gland invasion was calculated and analysis of demographic, clinical and pathological characteristics associated with thyroid gland invasion was performed.

Results

In all, 47 patients underwent total laryngectomy (40 treated with primary laryngectomy and seven treated with salvage laryngectomy following radiation failure or chemoradiation failure). Hemithyroidectomy was performed in 42 patients and the total thyroidectomy was performed in five patients. The overall frequency of invasion of the thyroid gland was 4.3%. Glandular involvement was seen in one advanced transglottic squamous cell carcinoma and one subglottic. In spite of thyroid cartilage invasion in 25.5% of cases detected in the preoperative radiological imaging, only one case demonstrated microscopic thyroid gland invasion.

Conclusions

Thyroidectomy may only be required during total laryngectomy for selected cases of advanced transglottic tumors and tumors with subglottic extension more than 10 mm.

Role of Thyroidectomy in Recurrent Laryngeal Carcinoma

OBJECTIVE

Management of recurrent laryngeal cancer presents a major challenge, and salvage laryngectomy is complicated by previous oncologic treatments. Thyroidectomy as part of salvage laryngectomy adds a nonnegligible degree of morbidity. The purpose of this study is to assess the rate of thyroid gland invasion in patients undergoing salvage laryngectomy to determine relevant predictive factors.

STUDY DESIGN

Case series with chart review.

SETTING

Department of Otorhinolaryngology, Head and Neck Surgery, Guy's Hospital, London, United Kingdom.

METHODS

A retrospective review of patients undergoing salvage laryngectomy between 2009 and 2019 was undertaken. Preoperative cross-sectional imaging and histopathological analysis were performed to define evidence and predictors of thyroid gland invasion (TGI).

RESULTS

Fifty-one patients had salvage laryngectomy. Histological evidence of TGI was found in 4 patients (7.8%). No significant relationship was found between histological TGI and subsite of primary carcinoma, degree of differentiation, T staging, or radiological TGI. Preoperative computed tomography had a high negative predictive value for TGI.

CONCLUSION

Thyroidectomy should be carefully considered in patients undergoing salvage laryngectomy, and its extent should be defined on an individual basis. Total thyroidectomy should not routinely be performed in salvage laryngectomy or pharyngolaryngectomy in patients with no preoperative radiological evidence of TGI on cross-sectional imaging, unless there is intraoperative evidence of TGI.

Onset of hypothyroidism after total laryngectomy: Effects of thyroid gland surgery and preoperative and postoperative radiotherapy

Background

To determine time of onset and risk of hypothyroidism after total laryngectomy (TL) with and without (hemi)thyroidectomy in relation to treatment regimen, that is, preoperative radiotherapy (RT‐TL), postoperative radiotherapy (TL‐RT), and postoperative re‐irradiation (RT‐TL‐RT).

Methods

Retrospective review of 128 patients treated by RT‐TL (51 patients), TL‐RT (55 patients), and RT‐TL‐RT (22 patients). Risk of hypothyroidism was determined by multivariable Cox regression analysis and euthyroid survival was calculated using Kaplan‐Meier method.

Results

Hypothyroidism developed in 69 (54%) patients. The median onset of hypothyroidism was later (P < .01) and the risk of hypothyroidism was lower (hazard ratio 0.49; P = .014) in the TL‐RT group compared to both other treatment regimens. Euthyroid survival did not differ between the treatment regimens. Two years euthyroid survival was 24% with and 61% without (hemi)thyroidectomy (P < .001).

Conclusions

Patients treated with TL‐RT have later onset of hypothyroidism. Higher risk for hypothyroidism is associated with salvage TL after radiotherapy and (hemi)thyroidectomy.

Factors contributing to unintentional parathyroidectomy during thyroid surgery

Unintentional parathyroidectomy during thyroid surgery has an incidence ranging between 1% and 31% across institutions. Many studies have identified malignancy and central neck dissection as risk factors for losing parathyroid glands, but few studies have evaluated the impact of other factors such as lymphocytic thyroiditis, hyperthyroidism, or concomitant primary hyperparathyroidism. The purpose of this study was to investigate which factors contribute to parathyroid loss during thyroid surgery. Charts of 269 patients undergoing thyroid surgery at a tertiary care medical center from 2010 to 2013 were retrospectively reviewed. Sixty-six patients (24.5%) experienced unintentional parathyroidectomy. Bivariate analysis showed no significant differences in patient characteristics. Patients with unintentional parathyroid removal had a significantly smaller largest thyroid nodule size (P = 0.002), higher rate of central neck dissection (30.3% vs 7.9%, P < 0.0001), and higher rate of malignancy (50% vs 36.0%, P = 0.04). Multivariable analysis showed that the strongest risk factor for unintentional parathyroidectomy was central neck dissection (P = 0.0008; odds ratio 4.72, confidence interval 1.91-11.71). In conclusion, central neck dissection for thyroid malignancy is the strongest risk factor for unintentional thyroidectomy. The presence of concomitant primary hyperparathyroidism, lymphocytic thyroiditis, or hyperthyroidism did not appear to increase the risk of unintentional parathyroidectomy.

Long-Term Endocrine and Metabolic Consequences of Cancer Treatment: A Systematic Review

The number of patients surviving ≥5 years after initial cancer diagnosis has significantly increased during the last decades due to considerable improvements in the treatment of many cancer entities. A negative consequence of this is that the emergence of long-term sequelae and endocrine disorders account for a high proportion of these. These late effects can occur decades after cancer treatment and affect up to 50% of childhood cancer survivors. Multiple predisposing factors for endocrine late effects have been identified, including radiation, sex, and age at the time of diagnosis. A systematic literature search has been conducted using the PubMed database to offer a detailed overview of the spectrum of late endocrine disorders following oncological treatment. Most data are based on late effects of treatment in former childhood cancer patients for whom specific guidelines and recommendations already exist, whereas current knowledge concerning late effects in adult-onset cancer survivors is much less clear. Endocrine sequelae of cancer therapy include functional alterations in hypothalamic-pituitary, thyroid, parathyroid, adrenal, and gonadal regulation as well as bone and metabolic complications. Surgery, radiotherapy, chemotherapy, and immunotherapy all contribute to these sequelae. Following irradiation, endocrine organs such as the thyroid are also at risk for subsequent malignancies. Although diagnosis and management of functional and neoplastic long-term consequences of cancer therapy are comparable to other causes of endocrine disorders, cancer survivors need individually structured follow-up care in specialized surveillance centers to improve care for this rapidly growing group of patients.

Subsequent thyroid disorders associated with treatment strategy in head and neck cancer patients: a nationwide cohort study

BACKGROUND

We investigated the risk of thyroid disorders, namely hypothyroidism, thyrotoxicosis and thyroiditis, in head and neck cancer patients undergoing multimodal treatment.

METHODS

A cohort study design using Taiwan's National Health Insurance Research Database was used to assess head and neck cancer patients over 20 years old. The cohort was divided into one group who underwent primary tumor excision only (PTE) and another with additional neck dissection (PTE + ND). The tumor sites were stratified to estimate the tumor-site-specific risk of thyroid disorders. The effect of subsequent resurgery, radiotherapy (RT), chemotherapy (CT), and concomitant (CCRT) or sequential chemoradiation therapy (sequential CT+ RT) on the risk of thyroid disorders was explored.

RESULTS

For 1999-2012, 7460 patients who underwent PTE + ND and 3730 who underwent PTE were enrolled and followed-up until the end of 2013. There were 122 and 50 patients in the two groups, respectively, who developed thyroid disorders, with no statistical difference between the groups. Patients with hypopharyngeal, oropharyngeal, or laryngeal cancer in the PTE + ND group had a higher risk of thyroid disorders (adjusted HR: 1.50, 95% CI: 0.67-3.38) than those in the PTE group when adjusted for covariates and mortality. Patients who underwent subsequent RT (adjusted HR: 3.64, 95% CI: 1.05-2.77) and CCRT (adjusted HR: 1.70, 95% CI: 1.05-2.77) after PTE + ND had a significantly higher risk of thyroid disorders.

CONCLUSION

RT results in a major risk of subsequent thyroid disorders, and ND may exacerbate this effect. Physicians should monitor thyroid function from two years after treatment initiation, especially in patients who undergo ND and subsequent RT.

A review on the dosimetrical and radiobiological prediction of radiation-induced hypothyroidism in radiation therapy of head-and-neck cancer, breast cancer, and Hodgkin’s lymphoma survivors

A review on the radiobiological modeling of radiation-induced hypothyroidism after radiation therapy of head-and-neck cancers, breast cancer, and Hodgkin’s lymphoma is presented. The current review is based on data relating to dose-volume constrains and normal tissue complication probability (NTCP) as a function of either radiobiological or (pre)treatment-clinical parameters. Also, these data were explored in order to provide more helpful criteria for radiobiological optimization of treatment plans involving thyroid gland as a critical normal organ.

Management of the thyroid gland during laryngectomy

OBJECTIVES

This study aimed to: describe the incidence of thyroid gland involvement in advanced laryngeal cancer, analyse patterns of spread to the thyroid and elucidate predictors of thyroid involvement.

METHODS

A retrospective review was performed on patients who underwent laryngectomy from 1991 to 2015 as a primary or salvage treatment for squamous cell carcinoma of the larynx, hypopharynx or base of tongue. The incidence of thyroidectomy during total laryngectomy, type of thyroidectomy, incidence of gland involvement, route of spread, and positive predictors of spread were analysed and reported.

RESULTS

A total of 188 patients fit the inclusion criteria. Of these, 125 (66 per cent) underwent thyroidectomy. The thyroid was involved in 10 of the 125 patients (8 per cent), 9 by direct extension and 1 by metastasis. Cartilage invasion was a predictor of thyroid gland involvement, with a positive predictive value of 26 per cent.

CONCLUSION

There is a low incidence of thyroid gland involvement in laryngeal carcinoma. Most cases of gland involvement occurred by direct extension. Thyroidectomy during laryngectomy should be considered for advanced stage tumours with cartilage invasion.

Thyroid gland invasion in advanced squamous cell carcinoma of the larynx and hypopharynx

Introduction

Squamous cell carcinoma of the larynx and hypopharynx has the potential to invade the thyroid gland. Despite this risk, the proposition of either partial or total thyroidectomy as part of the surgical treatment of all such cases remains controversial.

Objectives

To evaluate the frequency of invasion of the thyroid gland in patients with advanced laryngeal or hypopharyngeal squamous cell carcinoma submitted to total laryngectomy or pharyngolaryngectomy and thyroidectomy; to determine whether clinic-pathological characteristics can predict glandular involvement.

Methods

A retrospective case series with chart review, from January 1998 to July 2013, was undertaken in a tertiary care university medical center. An inception cohort of 83 patients with larynx/hypopharynx squamous cell carcinoma was considered. All patients had advanced stage disease (clinically T3–T4) and underwent total laryngectomy or total pharyngolaryngectomy in association with thyroidectomy. Adjuvant therapy was indicated when tumor or neck conditions required. Frequency of thyroid cartilage invasion was calculated; univariate and multivariate analysis of demographic, clinical and pathological characteristics associated with cartilage invasion were performed.

Results

The overall frequency of invasion of the thyroid gland was 18.1%. Glandular involvement was associated with invasion of the following structures: anterior commissure (odds ratio = 5.13; 95% confidence interval 1.07–24.5), subglottis (odds ratio = 12.44; 95% confidence interval 1.55–100.00) and cricoid cartilage (odds ratio = 15.95; 95% confidence interval 4.23–60.11).

Conclusions

Invasion of the thyroid gland is uncommon in the context of laryngopharyngeal squamous cell carcinoma. Clinical and pathological features such as invasion of the anterior commissure, subglottis and cricoid cartilage are more associated with glandular invasion.