The pathology and management of subglottic cancer

Survival analysis of patients with subglottic squamous cell carcinoma based on the SEER database

OBJECTIVE

This study aimed to investigate the demographic and clinicopathological characteristics, and survival outcomes of subglottic Squamous Cell Carcinoma (SCC) based on the Surveillance, Epidemiology, and End Results (SEER) database.

METHODS

Demographic and clinicopathological information, including age, sex, race, tumor size, histologic grade, clinical/TNM stage, tumor invasion extent, Lymph Node Metastasis (LNM) extent, size of metastatic lymph nodes, LNM ratio and treatment data, of 842 subglottic SCC patients diagnosed between 1996 and 2016 were acquired. Kaplan-Meier survival analyses were performed to assess the effects of clinicopathological characteristics, treatment modalities, surgical procedures, and adjuvant therapies on overall survival and cancer-specific survival.

RESULTS

Subglottic SCC was more frequent among males aged 60-70 years, with low-grade but locally advanced lesions without local or distant metastases. Age and several primary tumor/LNM related variables were independent risk factors for overall survival and cancer specific survival. Advanced-stage and high-grade disease led to unfavorable prognosis. The most common treatment modality and surgical procedure were surgery plus radiotherapy and total laryngectomy, respectively. Surgery plus radiotherapy provided favorable 5-year survival outcomes, while total laryngectomy had the worst. Surgery plus adjuvant therapy showed better survival outcomes than surgery alone.

CONCLUSION

This study confirmed the rarity of subglottic SCC. Patients with subglottic SCCs suffered poor prognosis especially for those with advanced-stage or high-grade lesions. The prognosis of subglottic SCC remained poor over the years, despite recent progress in cancer therapies. Surgery plus adjuvant therapy improved the survival outcome. Although larynx preservation surgery was beneficial for early-stage disease, total laryngectomy was favored for patients with advanced tumors.

LEVEL OF EVIDENCE

Level 4.

Magnetic Resonance Imaging-Based Delineation of Organs at Risk in the Head and Neck Region

Purpose

The aim of this article is to establish a comprehensive contouring guideline for treatment planning using only magnetic resonance images through an up-to-date set of organs at risk (OARs), recommended organ boundaries, and relevant suggestions for the magnetic resonance imaging (MRI)-based delineation of OARs in the head and neck (H&N) region.

Methods and Materials

After a detailed review of the literature, MRI data were collected from the H&N region of healthy volunteers. OARs were delineated in the axial, coronal, and sagittal planes on T2-weighted sequences. Every contour defined was revised by 4 radiation oncologists and subsequently by 2 independent senior experts (H&N radiation oncologist and radiologist). After revision, the final structures were presented to the consortium partners.

Results

A definitive consensus was reached after multi-institutional review. On that basis, we provided a detailed anatomic and functional description and specific MRI characteristics of the OARs.

Conclusions

In the era of precision radiation therapy, the need for well-built, straightforward contouring guidelines is on the rise. Precise, uniform, delineation-based, automated OAR segmentation on MRI may lead to increased accuracy in terms of organ boundaries and analysis of dose-dependent sequelae for an adequate definition of normal tissue complication probability.

Apatinib combined with concurrent chemoradiotherapy in patients with subglottic small cell carcinoma: a case report

Subglottic small cell carcinoma (SSMCC) is a rare type of neoplasm, meaning that laryngeal cancer guidelines in several countries, including the National Comprehensive Cancer Network (NCCN) guidelines, do not include treatment principles for SSMCC. Angiogenesis is an established factor in tumor initiation, growth, and dissemination. Apatinib mesylate, an orally administered drug, is a novel inhibitor of vascular endothelial growth factor receptor-2, a key mediator of angiogenesis, and has been shown to be safe and efficacious in the treatment of certain types of malignant tumors. To the best of our knowledge, there are few reports on the treatment of SSMCC with apatinib combined with concurrent chemoradiotherapy. In the present report of SSMCC in a 64-year-old woman, oral apatinib was given daily at a dose of 250 mg in combination with concurrent chemoradiotherapy; the only toxicities reported were mild leukopenia and finger numbness. Clear and rapid efficacy was observed with the disappearance of the tumor mass. Our findings indicate that apatinib combined with concurrent chemoradiotherapy may be effective in patients with SSMCC, with adverse reactions within the manageable range, thus representing an additional treatment option for this type of malignancy.

Results of surgical treatment alone for primary subglottic carcinoma

Primary subglottic carcinoma is rare and surgery is the most common therapeutic strategy for Chinese patients with this disease. To retrospectively evaluate surgically treated primary subglottic carcinoma treated with surgery. Patients with primary subglottic carcinoma who initially underwent surgery from 2005-2010 were grouped by surgical procedures with or without laryngeal function preservation and reviewed. Of 1815 patients with laryngeal cancer, 23 had a subglottic origin. Of these, 21 initially underwent surgery; 12 had 'early' (stage I/II) disease, and nine had 'advanced' (stage III/IV) disease. The actuarial 5-year OS was 73.9% [95% confidence interval (54.1% ∼ 93.7%)] for patients with squamous cell carcinoma. Among patients with early disease, the 5-year OS and DFS were 80% for partial laryngectomy and 71.4% for total laryngectomy. Patients with advanced disease underwent total laryngectomy, and the 5-year OS and DFS were 62.5%. Satisfactory oncologic outcomes can be achieved with initial surgery. Patients with early disease who underwent partial laryngectomy had a comparable prognosis to those who underwent total laryngectomy; deglutition and speech function were maintained.

Establishment of an immortalized human subglottic epithelial cell line

Objective

Translational research into subglottic disease is restricted by the availability of primary human tissue originating from this subsite. Primary epithelial cells are also limited by their inability to survive beyond several divisions in culture outside of the body. Specific subglottic cell lines, useful for in vitro studies, have not yet been described. We therefore demonstrate what we believe to be the first immortalized subglottic epithelial cell line.

Methods

Subglottic tissue was derived from a single adult patient's neoplasia‐free human subglottic brushing specimen. Cells were immortalized using a lentiviral vector expressing simian virus 40 T antigen. Karyotyping was performed on the transformed cells using single nucleotide polymorphism array comparative genomic hybridization. Transformed cells were phenotypically characterized by light microscopy, immunohistochemistry, and electrophysiology studies.

Results

The immortalized subglottic cell line (SG01) was able to divide successfully beyond 20 passages. Karyotyping demonstrated no significant genomic imbalance after immortalization. The cells demonstrated normal epithelial morphology and cytokeratin expression throughout. SG01 cells were also successfully cultured at air–liquid interface (ALI). At ALI cells demonstrated cilia, mucus production, and relevant ion channel expression.

Conclusion

The novel SG01 subglottic epithelial cell line has been established. This cell line provides a unique resource for researchers to investigate subglottic diseases, such as subglottic stenosis.

Level of Evidence

NA. Laryngoscope, 129:2640–2645, 2019

Treatment of early-stage laryngeal cancer: A comparison of treatment options

Over the course of the last several decades, the treatment options for early laryngeal cancers (T1 and T2) have evolved; however, simultaneously the mortality rate has increased. As larynx preservation approaches have become the standard of care, the selection of the proper treatment modality has become paramount. Radiation therapy or transoral laser microsurgery are the most common options for treatment of these early lesions. Oncologic and functional outcomes are considered equivalent between the two modalities for early glottic cancers; however, no direct comparisons exist for robust analysis. In terms of larynx preservation, there also is not compelling data favoring one treatment option or another. For early stage lesions, the goal for any larynx-sparing technique, either radiation or surgery, should be the intent to cure with single modality treatment and minimal short- and long-term toxicity. This article is designed to create a frame of reference for managing early stage disease with respect to lesions of the glottis and supraglottis while weighing treatment implications from an oncologic, functional, and cost perspective.

Adenoid cystic carcinoma of the larynx presenting with unusual subglottic mass: Case report

A 33-year-old woman presented with an unusual subglottic bulging mass accompanied by prolonged cough and wheeze. Laryngeal endoscopy revealed a bilateral, symmetrical mass immediately below the vocal cords with marked airway obstruction. Chronic subglottic laryngitis with inflammation or another condition such as amyloidosis was initially suspected. Cervicothoracic computed tomography revealed an obvious reduction of laryngeal caliber caused by an engulfing mass extending from just under the vocal cords to the cricoid ring, which was associated with thyroid, arytenoid, and cricoid cartilage destruction. Histopathological diagnosis of a biopsy specimen collected via a tracheotomy revealed that the lesion was a cT4aN0M0 adenoid cystic carcinoma (ACC) originating from the laryngeal minor salivary glands. The patient was treated by total laryngectomy with elective bilateral neck dissection under general anesthesia. Gross inspection of resected tissue confirmed yellowish-white, solid tumor mainly circumferentially encompassing the lumina of the cricoid ring. The histopathological findings confirmed typical ACC accompanied by a predominant cribriform appearance with no evidence of lymph node metastasis. The patient remains well and free of recurrence or metastasis. We herein describe laryngeal ACC and discuss radiological images and the surgical pathology.

Squamous cell carcinoma of the larynx with subglottic extension: is larynx preservation possible?

PURPOSE

Squamous cell carcinoma of larynx with subglottic extension (sSCC) is a rare location described to carry a poor prognosis. The aim of this study was to analyze outcomes and feasibility of larynx preservation in sSCC patients.

PATIENTS AND METHODS

Between 1996 and 2012, 197 patients with sSCC were treated at our institution and included in the analysis. Stage III-IV tumors accounted for 76%. Patients received surgery (62%), radiotherapy (RT) (18%), or induction chemotherapy (CT) (20%) as front-line therapy.

RESULTS

The 5-year actuarial overall survival (OS), locoregional control (LRC), and distant control rate were 59% (95% CI 51-68), 83% (95% CI 77-89), and 88% (95% CI 83-93), respectively, with a median follow-up of 54.4 months. There was no difference in OS and LRC according to front-line treatments or between primary subglottic cancer and glottosupraglottic cancers with subglottic extension. In the multivariate analysis, age > 60 years and positive N stage were the only predictors for OS (HR 2, 95% CI 1.2-3.6; HR1.9, 95% CI 1-3.5, respectively). A lower LRC was observed for T3 patients receiving a larynx preservation protocol as compared with those receiving a front-line surgery (HR 14.1, 95% CI 2.5-136.7; p = 0.02); however, no difference of ultimate LRC was observed according to the first therapy when including T3 patients who underwent salvage laryngectomy (p = 0.6). In patients receiving a larynx preservation protocol, the 5-year larynx-preservation rate was 55% (95% CI 43-68), with 36% in T3 patients. The 5-year larynx preservation rate was 81% (95% CI 65-96) and 35% (95% CI 20-51) for patients who received RT or induction CT as a front-line treatment, respectively.

CONCLUSION

Outcomes of sSCC are comparable with other laryngeal cancers when managed with modern therapeutic options. Larynx-preservation protocols could be a suitable option in T1-T2 (RT or chemo-RT) and selected T3 sSCC patients (induction CT).

[Results of definitive radiotherapy for squamous cell carcinomas of the larynx patients with subglottic extension]

BACKGROUND

Squamous cell carcinoma of larynx with subglottic extension is a rare location described to carry a poor prognosis. The aim of this study was to analyze outcomes and feasibility of definitive radiotherapy in patients with squamous cell carcinoma.

PATIENTS AND METHODS

Between 1998 and 2012, 56 patients with squamous cell carcinoma were treated at our institution and included in the analysis. Patients received definitive radiotherapy/chemoradiotherapy alone (63%) or after induction chemotherapy (37%) at our institute.

RESULTS

The 5-year actuarial overall survival, progression-free survival and specific survival were 64% (CI 95%: 48-90), 45% (CI 95%: 28-61), 88% (CI 95%: 78-98), respectively, with median follow-up of 74 months. The 5-year locoregional control was 69% (CI 95%: 56-83) and the 5-year distant control was 95% (CI 95%: 89-100). There was no difference in overall survival and locoregional control according to front-line treatments or between primary subglottic cancer and glotto-supraglottic cancers with subglottic extension. In the multivariate analysis, performance status of at least 1 and positive N stage were the only predictors for overall survival (hazard ratio [HR] [CI 95%]: 6.5 [1.3-34; P=0.03] and 11 [1.6-75; P=0.02], respectively). No difference of locoregional control was observed according to the first received therapy. The univariate analysis retrieved that T3-T4 patients had a lower locoregional control (HR: 3.1; CI 95%: 1.1-9.2, P=0.04), but no prognostic factor was retrieved in the multivariate analysis. In patients receiving a larynx preservation protocol, 5-year larynx preservation rate was 88% (CI 95%: 78-98), and 58% in T3 patients. The 5-year larynx preservation rate was 91% (CI 95%: 79-100) and 83% (CI 95%: 66-100) for patients who received radiotherapy/chemoradiotherapy or induction chemotherapy as a front-line treatment, respectively.

CONCLUSION

This analysis suggests that the results for squamous cell carcinoma patients treated with radiotherapy/chemoradiotherapy are comparable to those obtained for other laryngeal tumors. This thus suggests the feasibility of laryngeal preservation protocols for infringement subglottic for selected cases. Further studies are needed to clarify these preliminary data.

Efficacy and toxicity of (chemo)radiotherapy for primary subglottic cancer

BACKGROUND AND PURPOSE

Primary subglottic cancer is a rare malignancy. We investigated the efficacy and toxicity of radiotherapy for subglottic cancer.

PATIENTS AND METHODS

Nineteen patients with primary squamous cell carcinoma of the subglottis received radiotherapy, 14 of whom also underwent chemotherapy. Of the 19 patients, 15 received definitive radiotherapy to the gross tumors with total doses of 70-70.2 Gy in 35-39 fractions, and 4 underwent preoperative radiotherapy with total doses of 37.8-55.8 Gy in 21-31 fractions, followed by total laryngectomy.

RESULTS

Of the 19 patients, 5 developed local progression and 2 developed distant metastasis at the median follow-up period of 5 years. The 5-year local control and disease-free rates were 74 and 63%, respectively. Three patients died of tumor progression, and the 5-year overall and disease-free survival rates were 80 and 63%, respectively. Regarding acute toxicities, transient mucositis and dermatitis of grade 3 or lower were observed in all patients, but there were no late toxicities of grade 3 or higher.

CONCLUSION

Radiotherapy is a safe and effective treatment for patients with primary squamous cell carcinoma of the subglottis. The use of chemotherapy together with radiotherapy may enhance treatment efficacy and contribute to larynx preservation through good local control.

Thyroid gland management in total laryngectomy: Meta-analysis and surgical recommendations

Objectives: 1) Review the incidence of thyroid gland invasion by squamous cell laryngeal carcinoma reported in the literature. 2) Assess the association between thyroid gland invasion and anatomical characteristics of the laryngeal tumor.

Data Sources: MEDLINE (1967-2007) and EMBASE (1980-2007). These databases were supplemented with 61 patients from McGill University who underwent total laryngectomy with hemi- or total thyroidectomy from 2001-2006.

Review Methods: Systematic review for series of laryngeal carcinoma that commented on thyroid gland invasion according to tumor subsite and pathological characteristics. Total laryngectomy specimens for primary laryngeal squamous cell carcinoma with concomitant thyroid resection were included in the analysis.

Results: In total, eight series (n = 399) were included in the meta-analysis. Thyroid gland invasion was present in 33 laryngectomy specimens (8%); the principal method of invasion of the gland was by direct extralaryngeal extension. Subglottic extension > 10 mm (OR 7.22 [2.05 to 25.46]; P = 0.002), transglottic tumors (OR 3.23 [1.16 to 9.00]; P = 0.025), and subglottic subsite (OR 5.66 [1.34 to 23.87]; P = 0.018) were all significantly associated with thyroid gland invasion. Cartilaginous invasion by tumor was not a significant predictor of thyroid gland invasion ( P > 0.05).

Conclusions: Thyroid gland invasion is not a general feature of squamous cell laryngeal carcinoma. When present, it is strongly associated with anteroinferior spread of advanced laryngeal tumors. Thyroidectomy may only be required during total laryngectomy for transglottic tumors, subglottic tumors, and tumors with subglottic extension >10 mm.

The management dilemmas of invasive subglottic carcinoma

AIMS

To evaluate a single centre's experience with subglottic laryngeal carcinoma.

MATERIALS AND METHODS

The laryngeal cancer database at the Prince of Wales Hospital was sourced to define a sub-population of patients presenting with primary subglottic carcinoma. Excluded from the analysis were patients having a glottic origin for their carcinoma and secondarily involving the subglottis.

RESULTS

Of 969 patients with newly diagnosed laryngeal cancer, 10 (1%) had subglottic origin. T stage was six T2 and four T3, all were N0. A total laryngectomy was carried out in five patients, four of whom had postoperative radiotherapy, a hemilaryngectomy in one patient and definitive radiotherapy in four patients. There was only one local failure, who could not be salvaged, and one patient died locally controlled with metastatic disease. Thus, local control was achieved in nine of 10 patients.

CONCLUSION

Although an infrequent sub-population, subglottic carcinoma has a high likelihood of being locally controlled.

Squamous cell carcinoma of the subglottis

STUDY DESIGN

A retrospective study over a 25-year period of patients with laryngeal carcinoma treated by the Department of Otolaryngology at Wake Forest University.

METHODS

The boundaries of the subglottis were defined as 5 mm below the free edge of the true vocal folds extending to the inferior border of the cricoid cartilage. All were staged according to American Joint Committee on Cancer: stages I and II were considered early and stages III and IV as late. Patients were grouped by treatment modality of surgery alone, surgery and radiotherapy, radiotherapy alone, and radiotherapy with surgical salvage.

RESULTS

Fifteen patients represented 1.4% (15/1098) of laryngeal cancers diagnosed within that period. All patients had squamous cell carcinoma of the subglottis of which 20% (3/15) had early-stage disease (T1-T2) and 80% (12/15) had late-stage disease (T3-T4). Overall 3-year survival was low (25%) and is attributed to a high incidence of advanced-stage disease with a high rate of extralaryngeal spread and/or metastasis, especially to the lungs and paratracheal nodes.

CONCLUSIONS

To improve earlier detection by primary care physicians and otolaryngologists and to improve treatment outcome, awareness of subglottic carcinoma and its appropriate evaluation is critical in the patient presenting with hoarseness and/or stridor. Radiation therapy treatment to include the low and upper mediastinal compartments to cover local/regional extralaryngeal involvement is advocated as well as paratracheal lymphatic neck dissection and thyroidectomy in surgically treated lesions.

Imaging in laryngeal cancer: computed tomography, magnetic resonance imaging, positron emission tomography

Imaging modalities have become increasingly significant in the treatment of laryngeal cancer. The ability of CT and MR imaging to reveal pathologic conditions that are undetectable by palpation or endoscopy has led to the development of several imaging-based systems of anatomic classification and tumor staging. This article provides an up-to-date review of the radiographic evaluation of the normal neck and information for both the radiologist and clinician treating the patient with laryngeal cancer. Technical considerations, imaging-based staging systems, and the radiographic characteristics of laryngeal cancer in various regions of the neck are discussed.

Results of radiotherapy for primary subglottic squamous cell carcinoma

PURPOSE

To retrospectively evaluate the outcome after radical radiotherapy (RT) and surgical salvage and assess the risk of late toxicity for patients with primary subglottic squamous cell carcinoma treated at our center.

METHODS AND MATERIALS

Between 1971 and 1996, 43 patients with primary squamous cell carcinoma of the subglottis (35 men, 8 women) were treated with radical RT. All received megavoltage irradiation, most commonly to a dose of 50-52 Gy in 20 fractions during 4 weeks (39 patients). The median follow-up was 4.2 years.

RESULTS

Local control was achieved with RT alone in 24 (56%) of the 43 patients: 7 of 11 with T1, 8 of 12 with T2, 4 of 8 with T3, and 5 of 12 with T4. The 5-year actuarial local relapse-free rate was 52%. Subsequent local control was achieved in 11 of the 13 patients with failed RT and attempted surgical salvage, for an ultimate local control rate of 81.4% (35 of 43). The 5-year overall and cause-specific actuarial survival rate was 50.3% and 66.9%, respectively. No patients developed Grade 3 or 4 late radiation morbidity.

CONCLUSION

These data support the use of primary RT in the treatment of patients with primary squamous cell carcinoma of the subglottis as an appropriate treatment approach providing an option for laryngeal conservation.