Treatment discordance in the utilization of neck dissection for stage I-II supraglottic tumors

BACKGROUND

In 2018, the National Comprehensive Cancer Network treatment guidelines began recommending the use of neck dissection during surgical management of stage I-II supraglottic laryngeal squamous cell carcinoma (LSCC).

METHODS

Trends and factors associated with the use of neck dissection during larynx-preserving surgery for patients with cT1-2, N0, M0 supraglottic LSCC in the National Cancer Database (2004-2020) were evaluated using multivariable-adjusted logistic regression.

RESULTS

Of the 2080 patients who satisfied study eligibility criteria, 633 (30.4%) underwent neck dissection. Between 2018 and 2020, the rate of neck dissection was 39.0% (114/292). After multivariable adjustment, academic facility type, undergoing biopsy prior to surgery, and more radical surgery were significant predictors of receiving neck dissection.

CONCLUSIONS

The results of this national analysis suggest that the utilization of guideline-concordant neck dissection for management of stage I-II supraglottic LSCC remains low and highlight the need to promote the practice of neck dissection for this patient population.

Role of transoral robotic surgery in surgical treatment of early-stage supraglottic larynx carcinoma

BACKGROUND

There are several options for primary surgical treatment of early-stage supraglottic squamous cell carcinoma (SCC), including transoral robotic surgery (TORS). The purpose of this study was to compare outcomes of TORS to open partial laryngectomy and transoral laser microsurgery (TLM).

METHODS

Patients with clinical classification T1-2 supraglottic SCC diagnosed 2010-2019, treated with TORS, open partial laryngectomy, or TLM in the National Cancer Database were selected.

RESULTS

One thousand six hundred three patients were included: 17% TORS, 26.5% TLM, 56.5% open. TORS patients had the lowest rates of adjuvant treatment (28.4% vs. TLM: 45.0%, open: 38.5%, p < 0.001), and lower positive margin rates than TLM (16.9% vs. 30.5%, p < 0.001). Thirty-day and ninety-day post-operative mortality did not differ between the approaches. Five-year survival was higher following TORS compared to open surgery (77.8% vs. 66.1%, p = 0.01); this difference persisted following matched-pair analysis.

CONCLUSIONS

TORS may be a safe and effective surgical approach for early-stage supraglottic SCC in appropriate patients.

Transoral Laser Microsurgery With Neck Dissection Versus Radiotherapy for T2N0 Supraglottic Cancer

OBJECTIVES

To compare overall survival outcomes associated with transoral laser microsurgery (TLM) with neck dissection versus definitive radiotherapy in the management of T2N0 supraglottic squamous cell carcinoma.

METHODS

Data were extracted from the National Cancer Database concerning patients with cT2N0M0 supraglottic cancer treated with either TLM and neck dissection with minimum lymph node yield of 10 or definitive radiotherapy. Predictors of overall survival were assessed via Cox proportional hazards regression.

RESULTS

Seventy-six cT2N0 supraglottic squamous cell carcinoma patients who underwent TLM with neck dissection (+/- adjuvant therapy) versus 991 patients who underwent radiotherapy. TLM was associated with an overall survival benefit (OR = 0.574; 95% CI 0.383-0.860) compared with radiotherapy. There was no difference in survival between TLM patients receiving adjuvant treatment and those receiving definitive radiotherapy.

CONCLUSIONS

An up-front, TLM-based surgical approach to cT2N0 supraglottic cancer may offer an overall survival benefit compared with definitive radiotherapy, and should receive more frequent consideration as a primary approach to this disease process.

LEVEL OF EVIDENCE

3 Laryngoscope, 133:601-606, 2023.

Treating Head and Neck Cancer in the Age of Immunotherapy: A 2023 Update

Most patients diagnosed with head and neck squamous cell carcinoma (HNSCC) will present with locally advanced disease, requiring multimodality therapy. While this approach has a curative intent, a significant subset of these patients will develop locoregional failure and/or distant metastases. The prognosis of these patients is poor, and therapeutic options other than palliative chemotherapy are urgently needed. Epidermal growth factor receptor (EGFR) overexpression is an important factor in the pathogenesis of HNSCC, and a decade ago, the EGFR targeting monoclonal antibody cetuximab was approved for the treatment of late-stage HNSCC in different settings. In 2016, the anti-programmed death-1 (PD-1) immune checkpoint inhibitors nivolumab and pembrolizumab were both approved for the treatment of patients with recurrent or metastatic HNSCC with disease progression on or after platinum-containing chemotherapy, and in 2019, pembrolizumab was approved for first-line treatment (either as monotherapy in PD-L1 expressing tumors, or in combination with chemotherapy). Currently, trials are ongoing to include immune checkpoint inhibition in the (neo)adjuvant treatment of HNSCC as well as in novel combinations with other drugs in the recurrent/metastatic setting to improve response rates and survival and help overcome resistance mechanisms to immune checkpoint blockade. This article provides a comprehensive review of the management of head and neck cancers in the current era of immunotherapy.

Potentials of lncRNA-miRNA-mRNA networks as biomarkers for laryngeal squamous cell carcinoma

Chemoresistance, radioresistance, and facile spreading of laryngeal squamous cell carcinoma (LSCC) make the practically clinical treatment invalid. Such dismal outcome mainly originates from the lack of effective biomarkers which are highly desirable to understand the pathogenesis of LSCC, and strives to find promising novel biomarkers to improve early screening, effective treatment, and prognosis evaluation in LSCC. Recently, long non-coding RNAs (lncRNAs), a kind of non-coding RNAs longer than 200 nucleotides, can participate in the process of tumorigenesis and progression through many regulatory modalities, such as epigenetic transcriptional regulation and post-transcriptional regulation. Meanwhile, microRNAs (miRNAs, miRs), essentially involved in the post-transcriptional regulation of gene expression, are aberrantly expressed in cancer-related genomic regions or susceptible sites. An increasing number of studies have shown that lncRNAs are important regulators of miRNAs expression in LSCC, and that miRNAs can also target to regulate the expression of lncRNAs, and they can target to regulate downstream messenger RNAs (mRNAs) transcriptionally or post-transcriptionally, thereby affecting various physiopathological processes of LSCC. Complex cross-regulatory networks existing among lncRNAs, miRNAs, and mRNAs can regulate the tumorigenesis and development of LSCC. Such networks may become promising biomarkers and potential therapeutic targets in the research field of LSCC. In this review, we mainly summarize the latest research progress on the regulatory relationships among lncRNAs, miRNAs, and downstream mRNAs, and highlight the potential applications of lncRNA-miRNA-mRNA regulatory networks as biomarkers for the early diagnosis, epithelial-mesenchymal transition (EMT) process, chemoresistance, radioresistance, and prognosis of LSCC, aiming to provide important clues for understanding the pathogenesis of LSCC and developing new diagnostic and therapeutic strategies.

Presentation and outcomes of patients with clinically T1-2, N0 supraglottic squamous cell carcinoma: The role of definitive radiotherapy compared to primary partial laryngectomy

BACKGROUND

Early-stage supraglottic squamous cell carcinoma (SCC) is usually treated with a single modality. The aim of this study is to examine the role of radiotherapy (RT) versus partial laryngectomy (open, robotic-assisted, or endoscopic) with elective neck dissection (PL + END).

METHODS

A retrospective analysis of the National Cancer Database, 2010-2016. The study population included adult patients with clinically T1-2, N0 supraglottic SCC.

RESULTS

3301 patients were included. RT was performed in 93.52%, open PL + END in 2.64%, robotic-assisted PL + END in 1.33%, and endoscopic surgical resection in 2.51%. In the surgery group, T was upstaged in 23.36% and N was upstage in 16.36%. Five-year survival in the primary surgery group compared to RT group was 61.89% versus 77.46% (HR: 0.56, 95%CI: 0.43, 0.72).

CONCLUSIONS

T was upstaged in 23% of surgical patients. This accurate staging is likely missed in patients who undergo RT and possibly contributes to lower overall survival of this treatment group.

Prognostic value of pathological tumor size in patients with supraglottic carcinoma

BACKGROUND

The association between pathological tumor size and predictive value in patients with supraglottic carcinoma who receive surgery is poorly understood. To gain further insight into this association, the influence of postoperative tumor size assessed via pathological evaluation on survival outcomes in patients with supraglottic carcinoma was fully analyzed.

MATERIALS AND METHODS

This study collected data from 375 consecutive supraglottic carcinoma patients who underwent primary surgical treatment between 2005 and 2010. The parameters of tumor size, including tumor diameter, tumor area, and tumor volume, were used to analyze the prognostic abilities of overall survival (OS) and disease-free survival (DFS) in supraglottic carcinoma.

RESULTS

Twelve women and 363 men were included, with a mean age of 61.2 years. The 5-year OS and DFS rates were 65.4% and 56.2%, respectively. The mean tumor diameter, tumor area, and tumor volume of all patients was 3.1 cm, 8.6 cm², and 9.1 cm³, respectively. Tumors with higher pT stages had a larger tumor diameter, tumor area, and tumor volume. These three factors were significantly correlated with pT stage, and tumor volume was the strongest factor contributing to pT stage. Patients with a larger tumor diameter, tumor area, and tumor volume had worse OS and DFS. Tumor area and tumor volume were independent prognostic factors of OS and DFS in supraglottic carcinoma patients.

CONCLUSIONS

Patients with a larger tumor size have inferior survival outcomes, and tumor area and tumor volume are independent predictive parameters of survival in supraglottic carcinoma patients who are treated with primary surgery.

Comparison of long-term treatment outcomes of T2N0M0 laryngeal squamous cell carcinoma using different treatment methods

Early [stage I and II (T2N0M0)] laryngeal cancer types are currently recommended to be treated with a single modality, consisting of definitive radiation therapy or larynx-preserving surgery. Although the treatment outcomes of stage I are good, the frequency of successful outcomes decreases with T2N0M0. Therefore, the present study investigated the treatment outcomes of different treatment methods in T2N0M0 laryngeal cancer. In total, 83 patients with previously untreated T2N0M0 laryngeal squamous cell carcinoma were enrolled. Patients were grouped by treatment method: Radiation therapy (RT; 27 patients); chemoradiotherapy (CRT; 46 patients) with cisplatin base; and surgery-based therapy (SBT; ten patients). The recurrence rates of the RT, CRT and SBT groups were 44.4, 19.6 and 50%, respectively. Moreover, the local control rates of the RT, CRT and SBT groups were 55.6, 87.0 and 80%, respectively. The CRT group had a significantly lower recurrence rate and higher local control rate compared with the RT group (P<0.05). In the survival analysis, overall and disease-specific survival rate did not differ significantly among the treatment groups. However, 3- and 5-year disease-free survival rates (DFS) of the RT group were both 55%, those of the SBT group were both 50% and those of the CRT group were both 80%. Furthermore, the DFS was significantly higher in CRT group compared with the other groups (P=0.02). Using multivariate analysis with Cox regression, it was found that the treatment method was the most important factor for DFS and had a significant impact in the CRT group. In addition, in patients with glottic cancer with anterior commissure and subglottic invasion, the CRT group had significantly improved DFS compared with the RT group, whereas there was no significant difference between the two groups in patients without subglottic invasion. According to National Cancer Institution Common Toxicity Criteria (version 5.0), more patients had toxicity in the CRT group compared with the RT group. However, in the RT and CRT groups, no patients demonstrated mortality due to toxicity, and treatment-related toxicities were manageable. Collectively, although definitive conclusions could not be established, due to the limitations of this retrospective study, the results suggest that CRT had a positive impact on the local control and DFS rates with manageable toxicity in patients with T2N0M0 laryngeal cancer.

Functional outcomes in early (T1/T2) supraglottic cancer: a systematic review

OBJECTIVES

Organ preserving surgery (OPS) and radiotherapy (RT) are both accepted treatment options for early stage supraglottic cancer (SGC). Radiation has supplanted surgery in most cases, because of the perception that surgery results in poorer functional outcomes. However, evidence suggests that OPS with a neck dissection may be associated with improved survival. Our objective was to conduct a systematic review of the literature to compare functional outcomes of OPS and RT for early SGC.

METHODS

We searched Medline, EMBASE and Cochrane Central Register of Controlled Trials to identify studies. Studies were included if they reported functional outcomes on 10 or more patients with early stage SGC treated with radiation or OPS, including open partial laryngectomy, transoral laser microsurgery (TLM) or transoral robotic surgery (TORS). Two reviewers independently screened articles for relevance using pre-determined criteria.

RESULTS

From 7720 references, we included 10 articles (n = 640 patients). 50% (n = 320) of patients were treated with surgery. Three head-to-head RT versus OPS papers were included, however different outcome measures were used for each group. Intractable aspiration management (including total laryngectomy or permanent tracheostomy) following OPS was reported in five papers representing 186 patients; the definitive intractable aspiration management rate was 2.6% (95% CI 1.0-6.8%). Four papers reported permanent G-tube rate for the surgical group (n = 198), calculating a rate of 5.3% (95% CI 2.6-10.5%), this was not reported for the RT group in any papers. One study reported quality of life. Two studies reported objective voice measures.

CONCLUSIONS

This systematic review revealed a paucity of objective measures and significant data heterogeneity, rendering the comparison of functional outcomes following OPS versus RT for early SGC limited. Future research should include objective measures of functional outcomes including laryngectomy rate, g-tube rate, tracheostomy dependence, quality of life, and voice quality measures.

Knockdown of DGCR5 enhances the radiosensitivity of human laryngeal carcinoma cells via inducing miR-195

Long noncoding RNAs (lncRNAs) exert critical roles in the development of various cancers, including human laryngeal cancer. Radioresistance contributes to the predominant causes of laryngeal cancer recurrence after radiotherapy. The aim of our study was to investigate the association of dysregulated lncRNA and radiation resistance in human larynx squamous carcinoma. Here, we investigated the biological roles of lncRNA DiGeorge syndrome critical region gene 5 (DGCR5) in radioresistance of human laryngeal cancer. Two human larynx squamous carcinoma cell lines (Hep-2 and Hep-2R), with different radiosensitivities in vitro were used in the present study. We observed that DGCR5 was significantly upregulated in Hep-2R cells. Inhibition of DGCR5 by LV-shDGCR5 transfection restrained Hep-2R cell proliferation and sensitized cells to radiation. Reversely, overexpression of DGCR5 exhibited an opposite phenomenon in vitro. In addition, microRNA (miR)-195 was predicted as a direct downstream target of DGCR5. Dual-luciferase reporter and RNA immunoprecipitation assays verified the direct interaction between them. Meanwhile, miR-195 was observed to be reduced in Hep-2R cells and miR-195 mimics repressed Hep-2 cell growth. Moreover, radiosensitivity of Hep-2R cells was greatly enhanced by overexpression of miR-195, which could be reversed by upregulation of DGCR5. Finally, in vivo experiments were used to validate that knockdown of DGCR5 suppressed laryngeal carcinoma via targeting miR-195. In conclusion, we indicated that DGCR5 could contribute to the radioresistance of human laryngeal carcinoma cells via sponging miR-195.

Supraglottic Squamous Cell Carcinoma: A Population-Based Study of 22,675 Cases

OBJECTIVES/HYPOTHESIS

The authors used the Surveillance, Epidemiology, and End Results (SEER) database to analyze epidemiological features of patients presenting with supraglottic squamous cell carcinoma (SCCa) and to evaluate treatment trends and outcomes.

METHODS

The SEER database was queried for patients with supraglottic SCCa from 1973 to 2013. Information on demographics; tumor size; histologic grade; American Joint Committee on Cancer (AJCC) stage; SEER local, regional, distant stage; and treatment modality were analyzed.

RESULTS

There were 22,675 cases of primary supraglottic SCCa identified. The mean age at diagnosis was 62.3 years, with males accounting for 70.3% of all cases. A high percentage of patients presented with stage IV disease (44.9%). The most common treatment modality was radiotherapy (46.6%), followed by combination of surgery and radiotherapy (29.2%) and surgery alone (15.0%). Overall 5-year disease-specific survival (DSS) for all cases was 54.0%. When stratified by treatment modality, 5-year DSS was best for patients receiving surgery alone (64.2%). However, for patients with AJCC stage IV disease, survival was significantly better with combined surgery and radiotherapy (52.5%).

CONCLUSION

In general, supraglottic SCCa is treated most commonly with radiotherapy, followed by surgery and radiotherapy. Patients managed surgically had better 5-year DSS when compared to patients treated by other modalities. However, when stratified by stage, patients with AJCC stage IV disease had significantly better survival with combined surgery and radiotherapy. Of patients receiving surgery, supraglottic laryngectomy was found to have a significantly better 5-year DSS when compared to both total laryngectomy and laryngectomy, not otherwise specified.

LEVEL OF EVIDENCE

NA Laryngoscope, 129:1822-1827, 2019.

Treatment of early stage Supraglottic squamous cell carcinoma: meta-analysis comparing primary surgery versus primary radiotherapy

Objectives

For early stage supraglottic squamous cell carcinoma (SCC), single modality treatment either in the form of primary organ preservation surgery alone or radiation alone is recommended. Thus, a definite treatment strategy for early stage supraglottic SCC remains undefined. The primary objective of this study was to conduct a systematic review and meta-analysis comparing the oncologic outcomes of surgery and radiotherapy in early stage (Stage I and II) T1 N0 and T2 N0 supraglottic SCC.

Methods

Systematic methods were used to identify published and unpublished data. Two reviewers independently screened all titles, abstracts and articles for relevance using predefined criteria. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated.

Results

Five studies met the inclusion criteria for disease specific mortality with a total of 2864 pooled patients. 5-year disease specific mortality was lower in the surgery group (ORs 0.43, 95% CI 0.31–0.60). Four studies met the inclusion criteria for 5-year overall mortality with a total of 2790 pooled patients. Five-year overall mortality was lower in surgery group (ORs 0.40, 95% CI 0.29–0.55).

Conclusions

This is the first study to examine the management of early stage supraglottic SCC using meta-analytic methodology. Our results suggest that primary surgery may result in decreased disease specific and overall mortality compared to primary radiotherapy.

Survival Outcomes in Patients with T2N0M0 (Stage II) Squamous Cell Carcinoma of the Larynx

Objective Emerging data have demonstrated suboptimal outcomes among patients with stage II larynx cancer. Our objective is to report survival outcomes for T2N0M0 larynx cancer and to determine the cause-specific survival. Study Design Case series with planned data collection. Setting Tertiary academic center. Subjects Adults with T2N0M0 squamous cell carcinoma of the larynx treated with curative intent. Methods A head and neck cancer epidemiology database was queried for eligible subjects from 2003 to 2014. Data were extracted from the electronic medical record and research database, and survival analyses were performed. Results Thirty-four patients with previously untreated stage II larynx cancer were identified (median follow-up 48 months). Patients included 27 males and 7 females with a mean age of 59 years. The majority of tumors arose from the glottis (59%). Of the cohort, 12% were treated with surgery, 65% radiation therapy, and 24% chemoradiation therapy. The estimated 2-year overall survival was 81%, (95% confidence interval [CI], 59%-92%), disease-specific survival was 91% (95% CI, 69%-98%), and recurrence-free survival was 84% (95% CI, 65%-93%). Four of 5 patients with persistent or recurrent disease posttreatment were successfully salvaged with total laryngectomy with 100% locoregional control. There were 11 mortalities (2 disease related, 2 due to metachronous primaries, 3 treatment related, and 4 from other/unknown causes). Conclusion Stage II laryngeal cancer has suboptimal survival outcomes. This appears to be a reflection of medical comorbidities, propensity for metachronous primaries, and the sequelae of late treatment effects rather than poor locoregional control.

Phosphorylated FADD is not prognostic for local control in T1-T2 supraglottic laryngeal carcinoma treated with radiotherapy

OBJECTIVE

The Fas-Associated Death Domain (FADD) gene is located in the chromosome 11q13-region and frequently is amplified in head and neck squamous cell carcinoma. Expression of FADD and its phosphorylated isoform (pFADD) have been associated with aggressive tumor growth, lymph node metastasis, and overall survival. Previously, we demonstrated that pFADD expression was related to a significantly improved local control in early stage (tumor [T]1 to T2) glottic laryngeal squamous cell carcinoma (LSCC). The aim of this study was to examine the prognostic value of pFADD and FADD in T1 to T2 supraglottic LSCC treated with primarily radiotherapy.

METHODS

Tumor tissue sections of 60 patients with T1 to T2 supraglottic LSCC treated with primarily radiotherapy were assessed immunohistochemically for expression of pFADD and FADD. Expression percentages and clinical parameters and their associations with clinical outcome were studied using Cox regression and Kaplan-Meier survival analyses. Expression percentages in supraglottic and glottic LSCC were compared using the Mann-Whitney U test.

RESULTS

Expression of pFADD and FADD in supraglottic and glottic LSCC did not significantly differ. In supraglottic LSCC, both pFADD and FADD did not show prognostic value for local control (hazard ratio [HR] 1.00, 95% confidence interval [CI] 0.98-1.03; HR 1.03, 95% CI 0.60-1.78, respectively) and overall survival (HR 0.99, 95% CI 0.98-1.01; HR 1.19, 95% CI 0.83-1.71 respectively). In this cohort, lymph node status was the best predictor for local control (HR 3.73, 95% CI 1.30-10.67).

CONCLUSION

In this homogeneous cohort of T1 to T2 supraglottic LSCC primarily treated with radiotherapy, lymph node status was associated with local recurrence, whereas the expression of pFADD was not.

LEVEL OF EVIDENCE

NA. Laryngoscope, 127:E301-E307, 2017.

Laryngeal Preservation in Glottic Cancer

Objective

When total laryngectomy is not required, organ preservation surgery or radiotherapy is considered the standard of care for primary glottic cancer. These accepted treatment options are available for early and advanced glottic cancers due to equivalent locoregional control and survival rates. However, in today’s climate of accountable care, the financial burden of treatment choices continues to increase in significance. We therefore compared hospital charges and treatment-related morbidity between organ-preserving surgery and radiation with or without chemotherapy—herein, (chemo)radiation—in the primary treatment of glottic cancer.

Study Design

Nationwide Inpatient Sample Database was analyzed to assess clinical and financial information.

Setting

Population-based analysis.

Subjects

Patients (N = 5499) with primary glottic cancer undergoing treatment with laryngeal preservation strategies.

Methods

Patients were subdivided by ICD-9 codes into 3 treatment groups: endoscopic resection, open partial laryngectomy, and (chemo)radiation. Treatment-related outcomes, charges, and length of hospitalization were analyzed among treatment groups.

Results

When adjusting for sex, age, race, comorbidity, and primary payer, (chemo)radiotherapy was associated with increased direct charges ( P < .001; coefficient, $23,658.99; 95% confidence interval [95% CI]: $10,227.15-$37,090.84) and length of hospitalization ( P < .001; hazard ratio, 0.593; 95% CI: 0.502-0.702) when compared with endoscopic surgery. As compared with open surgery, endoscopic surgery was associated with reduced hospital charges ( P = .012; coefficient, $11,967.01; 95% CI: $2,784.17-$21,249.85) and duration of hospitalization ( P < .001; hazard ratio, 0.749; 95% CI: 0.641-0.876).

Conclusions

This analysis suggests that increased utilization of endoscopic surgery in patients with primary glottic cancer not requiring total laryngectomy may lead to reduced financial burden and duration of hospitalization when compared with open surgery or (chemo)radiation therapy.

Functional Outcomes after Salvage Transoral Laser Microsurgery for Laryngeal Squamous Cell Carcinoma

OBJECTIVES

Transoral laser microsurgery (TLM) has been increasingly used in lieu of total laryngectomy to treat malignancy after definitive radiation. There are few data in the literature regarding functional outcomes. We retrospectively reviewed voice and swallowing outcomes in patients who underwent TLM for recurrent laryngeal carcinoma.

STUDY DESIGN

Case series with chart review.

SETTING

Tertiary care center.

SUBJECTS AND METHODS

Forty-two patients were identified with recurrent squamous cell carcinoma of the larynx after definitive radiation therapy from 2001 to 2013: 28 patients with glottic recurrence and 14 with supraglottic recurrence. Swallowing outcomes were evaluated by gastrostomy tube dependence, the MD Anderson Dysphagia Inventory, and the Functional Oral Intake Scale. Voice outcomes were evaluated by the Voice Handicap Index and observer-rated perceptual analysis.

RESULTS

No significant difference was noted between mean pre- and postoperative MD Anderson Dysphagia Inventory scores: 78.25 and 74.9, respectively (P = .118, t = 1.6955). Mean Functional Oral Intake Scale scores after TLM for supraglottic and glottic recurrences were 6.4 and 6.6, respectively. Of 42 patients, 17 (40.5%) required a gastrostomy tube either during radiation or in conjunction with the salvage procedure. Of 17 patients, 15 resumed sufficient oral diet for tube removal. Patients' mean Voice Handicap Index score did increase from 34.3 to 51.5 (P = .047), and their mean perceptual score did decrease from 60.0 to 45.3 (P = .005). However, at 1-year follow-up, there was no significant difference in perceptual score: 61.1 to 57.1 (P = .722).

CONCLUSIONS

TLM is a successful surgical option for recurrent laryngeal cancer with acceptable functional outcomes.

Regulatory effects of WRAP53 on radiosensitivity of laryngeal squamous cell carcinoma cells

BACKGROUND

Telomere length is closely associated with cellular radiosensitivity and WRAP53 is required for telomere addition by telomerase. In this research we assessed radiosensitivity of laryngeal squamous cell carcinoma Hep-2 cell lines after WRAP53 inhibition, and analyzed the molecular mechanisms.

MATERIALS AND METHODS

phWRAP53-siRNA and pNeg-siRNA were constructed and transfected into Hep-2 cells with lipofectamine. Expression of WRAP53 was analyzed by RT-PCR and Western-blottin, radiosensitivity of Hep-2 cells was assessed colony formation assay, and the relative length of telomeres was measured by QPCR.

RESULTS

The data revealed that the plasmid of phWRAP53-siRNA was constructed successfully, and the mRNA and protein levels of WRAP53 were both obviously reduced in the Hep-2 cell line transfected with phWRAP53-siRNA. After Hep-2 cells were irradiated with X-rays, the D0 and SF2 were 2.481 and 0.472, respectively, in the phWRAP53-siRNA group, much lower than in the control group (D0 and SF2 of 3.213 and 0.592) (P<0.01). The relative telomere length in the phWRAP53-siRNA group was 0.185±0.01, much lower than in the untreated group (0.523±0.06) and the control group (0.435±0.01).

CONCLUSIONS

Decreasing the expression of WRAP53 using RNA interference technique can enhance the radiosensitivity of Hep-2 cell lines by influencing the telomere length. WRAP53 is expected to be a new target to regulate the radiosensitization of tumor cells.