Endoscopic submucosal dissection for lesions developing in the irradiated area of head and neck cancer.

BACKGROUND AND AIM: Effective treatment of lesions that develop in the irradiated area of head and neck squamous cell carcinoma is a major concern. This study aimed to clarify the efficacy and safety of endoscopic resection for such lesions. METHODS: Among consecutive patients who underwent endoscopic resection for histologically proven head and neck squamous cell carcinoma between January 2014 and December 2021, those who received definitive radiotherapy/chemoradiotherapy before endoscopic resection were included in this single-center, retrospective study. Short- and long-term outcomes were evaluated. RESULTS: Among 422 patients who underwent endoscopic resection for 615 lesions, 43 patients with 57 lesions were eligible. All 57 lesions were treated with endoscopic submucosal dissection and en bloc resection was achieved in all lesions. Grade 3 of Common Toxicity Criteria for Adverse Events v5.0 occurred in eight (19%) patients (dysphagia, seven; stricture, three; aspiration pneumonia, two; and pharyngeal necrosis, one [some cases overlapped]), but no grade ≥ 4 events occurred. Enteral nutrition by gastrostomy was temporarily required in two patients owing to dysphagia and laryngeal necrosis. During the median follow-up of 40 (interquartile range, 29.5-61) months after endoscopic submucosal dissection for the lesions developed in the irradiated area, local recurrence and metachronous lesions developed in two (5%) and nine (21%) patients, respectively. However, total laryngectomies and tracheostomies were avoided in all patients. The 3-year overall and disease-specific survivals were 81% (95% confidence interval, 64%-91%) and 94% (95% confidence interval, 79%-99%), respectively. CONCLUSIONS: Favorable local control and safety of endoscopic submucosal dissection were demonstrated.

Boron delivery for boron neutron capture therapy targeting a cancer-upregulated oligopeptide transporter.

Boron neutron capture therapy (BNCT) is a radiotherapy utilizing the neutron capture and nuclear fission reaction of 10B taken up into tumor cells. The most commonly used boron agent in BNCT, p-borono-l-phenylalanine (BPA), is accumulated in tumors by amino acid transporters upregulated in tumor cells. Here, by using dipeptides of BPA and tyrosine (BPA-Tyr and Tyr-BPA), we propose a novel strategy of selective boron delivery into tumor cells via oligopeptide transporter PEPT1 upregulated in various cancers. Kinetic analyses indicated that BPA-Tyr and Tyr-BPA are transported by oligopeptide transporters, PEPT1 and PEPT2. The intrinsic oligopeptide transport activity in tumor cells clearly correlated with PEPT1 protein expression level but not with PEPT2, suggesting that PEPT1 is the predominant oligopeptide transporter at least in tumor cell lines. Furthermore, using BPA-Tyr and Tyr-BPA, boron was successfully delivered into PEPT1-expressing pancreatic cancer AsPC-1 cells via a PEPT1-mediated mechanism. Intravenous administration of BPA-Tyr into the mice bearing AsPC-1 xenograft tumors resulted in significant boron accumulation in the tumors. It is proposed that the oligopeptide transporters, especially PEPT1, are promising candidates for molecular targets of boron delivery in BNCT. The BPA-containing dipeptides would have a potential for the development of novel boron carriers targeting PEPT1.

Metabolic tumor volume of primary tumor predicts survival better than T classification in the larynx preservation approach.

We aimed to determine whether pretreatment metabolic tumor volume of the primary tumor (T-MTV) or T classification would be a better predictor of laryngectomy-free survival (LFS) and overall survival (OS) after chemoradiotherapy in patients with locally advanced laryngeal or hypopharyngeal cancer requiring total laryngectomy. We analyzed 85 patients using a Cox proportional hazards model and evaluated its usefulness by Akaike's information criterion. A T-MTV cut-off value was determined by time-dependent receiver operating characteristic curve analysis. Interobserver reliability for measuring T-MTV was estimated by the intraclass correlation coefficient (ICC). After adjustment for covariables, T-MTV, irrespective of whether a continuous or dichotomized variable, and T classification remained independent predictors of LFS and OS. Large T-MTV (>28.7 mL) was associated with inferior LFS (hazard ratio [HR], 4.16; 95% confidence interval [CI], 1.97-8.70; P = 0.0003) and inferior OS (HR, 3.18; 95% CI, 1.47-6.69; P = 0.004) compared with small T-MTV (≤28.7 mL). The T-MTV model outperformed the T classification model in predicting LFS and OS (P = 0.007 and 0.01, respectively). Three-year LFS and OS rates for patients with small versus large T-MTV were 68% vs 9% (P < 0.0001) and 77% vs 25% (P < 0.0001), respectively, whereas those for patients with T2-T3 versus T4a were 61% vs 31% (P = 0.003) and 71% vs 48% (P = 0.10), respectively. ICC was 0.99 (95% CI, 0.99-1.00). Given the excellent interobserver reliability, T-MTV is better than T classification to identify patients who would benefit from the larynx preservation approach.

The impact of COVID-19 pandemic on head and neck cancer diagnosis and treatment.

Background/purpose: Following the COVID-19 pandemic, there were reports of diagnostic delays and a surge in the prevalence of advanced head and neck cancer (HNC). We conducted a retrospective study on the impact of COVID-19 on the number of newly diagnosed HNC among patients who underwent screening at our center to understand the temporal changes. Materials and methods: We investigated the Union for International Cancer Control guidelines-TNM classification, presence of subjective symptoms at the time of consultation, and initial treatment from the medical records of first-time patients with HNC who visited our head and neck surgery department during 2019-2021 and compared them with those before (2019) and after (2020-2021) the pandemic. Results: A total of 1245 patients were included in the study. The number of patients were 437, 417, and 391 in 2019, 2020, and 2021, respectively, indicating a downward trend following the pandemic. When the incidence of early (stage 0-II) and advanced (stage III-IV) HNC cancers was compared, the proportion of patients with early-stage cancer declined. Among them, significant primary tumor progression was observed in T classification. The number of patients with no subjective symptoms at initial diagnosis was decreasing significantly. Conclusion: A decrease in the proportion of HNC patients with early-stage cancer and primary tumor progression was observed after the pandemic in 2020 and 2021. The number of early-stage malignancies may have dropped due to patients' unwillingness to visit a doctor.

Extent of thyroidectomy and paratracheal lymph node dissection in total pharyngolaryngectomy for pyriform sinus cancer, and recurrence, survival, and postoperative hypoparathyroidism: A multicenter retrospective study.

BACKGROUND: Total pharyngolaryngectomy (TPL) is standard treatment for hypopharyngeal cancer. However, extensive thyroidectomy and paratracheal nodal dissection (PTND) can cause hypoparathyroidism. We sought to determine the optimum extent of resection. METHODS: We analyzed the clinicopathological information of 161 pyriform sinus cancer patients undergoing TPL from 25 Japanese institutions. Rates of recurrence and risk factors for hypoparathyroidism, as well as incidence of pathological contralateral level VI nodal metastasis and stomal recurrence, were investigated. RESULTS: The extent of thyroidectomy and nodal dissection were not independent risk factors for recurrence. Incidences of contralateral level VI nodal involvement and stomal recurrence were 1.8% and 1.2%, respectively. Patients undergoing hemithyroidectomy/ipsilateral PTND did not develop stomal recurrence and had the lowest incidence of hypoparathyroidism. Prognosis in patients without tracheostomy prior to hemithyroidectomy/ipsilateral PTND was comparable to that with more extensive resections. CONCLUSIONS: Hemithyroidectomy/ipsilateral PTND may be sufficient for pyriform sinus cancer cases without tracheostomy.

Vestibular type of Mondini anomalies with BPPV and Meniere's disease-like symptoms.

An extremely rare case with labyrinthine anomaly with normal hearing was demonstrated. This case firstly showed transient positioning vertigo like benign paroxysmal positional vertigo (BPPV) and subsequently episodic vertigo like Meniere's disease. A 55-year-old male attended our hospital, complaining of transient but persistent positioning vertigo in 2004. The apogeotropic positioning nystagmus was observed in spine position. In 2005, he came to feel episodic vertigo continuously for more than 30min like Meniere's disease. We examined CT scan and 3D-MRI, indicating the hypoplastic lateral semicircular canal (L-SCC) fused together with enlarged vestibule on the left side. We finally diagnosed this case as Mondini anomaly on the left side. The imaging analysis is the most useful for differential diagnosis of Mondini anomalies, because symptoms in these patients are actually various due to the individual inner ear condition. The mechanism of generation of BPPV-like vertigo: the otolith in deformed utricle might be transferred into the fused space with vestibule and L-SCC, resulting in the irrigation of the hypoplastic cupula. The mechanism of generation of Meniere's disease-like vertigo: neuro-otologic findings with furosemide test implied endolymphatic hydrops on the left side. Meniere's disease-like episodic vertigo could be due to subsequently generated endolymphatic hydrops.