Buichiro Shin

Clinical study of parapharyngeal space tumours

This study reviewed 24 cases of parapharyngeal space tumour treated at Kurume University Hospital between 1990 and 2007. Histological diagnoses were generally obtained from the excised tumour (22/24). Seventy-seven per cent of the parapharyngeal space tumours were benign and 23 per cent were malignant. Thirty-eight per cent (eight of 22) of these tumours were pleomorphic adenomas and 23 per cent (five of 22) were schwannomas. A transparotidectomy and transcervical approach were used in 88 per cent (15/17) of benign tumours. A mandibular swing approach was used for one malignant tumour. Post-operative complications were identified in 16 of 22 patients. The most common complication, facial nerve paralysis, was identified in eight patients, and seven of these patients demonstrated first bite syndrome. In consideration of the high incidence of post-operative complications, the surgical approach should therefore be carefully selected when treating patients with parapharyngeal space tumours.

Histoanatomical characteristics to increase the success in transoral surgery for hypopharyngeal cancer

Transoral laser microsurgery (TLM) for hypopharyngeal cancer results in a lower incidence of complications than conventional open surgery. However, additional knowledge regarding the histoanatomical characteristics of the hypopharynx is necessary to prevent severe complications during TLM. The purpose of this study is to investigate the histoanatomical characteristics of the hypopharynx for TLM.

Prognostic stratification of patients with nasopharyngeal carcinoma based on tumor immune microenvironment

Little is known about immune‐related prognostic factors in patients with nasopharyngeal carcinoma (NPC).

Association between PD-L1 expression combined with tumor-infiltrating lymphocytes and the prognosis of patients with advanced hypopharyngeal squamous cell carcinoma

Limited information is available regarding the immune-related prognostic factors of patients with advanced hypopharyngeal squamous cell carcinoma (HPSCC). The expression of programmed cell death-ligand 1 (PD-L1) in tumor cells contributes to a mechanism that allows cancer cells to escape immune surveillance. We investigated whether PD-L1 or human leukocyte antigen (HLA) class I expression in tumor cells and the tumor-infiltrating lymphocyte (TIL) density were associated with the tumor response to neoadjuvant chemotherapy (NAC) and survival in patients with advanced HPSCC. We retrospectively reviewed 83 consecutive patients with stage III or IV HPSCC who received NAC. We evaluated PD-L1 and HLA class I expression and TIL density using immunohistochemistry. Univariate and multivariate analyses demonstrated that CD8+ TIL density was an independent and significant predictive factor for the response to NAC, progression-free survival (PFS) and overall survival (OS), whereas PD-L1 or HLA class I expression did not significantly correlate. The subgroup analysis revealed that a higher CD8+ TIL density without detectable PD-L1 expression tended to be associated with longer patient survival. These results suggest that PD-L1 expression levels combined with CD8+ TIL density may serve as a predictive biomarker for patients with stage III or IV HPSCC receiving NAC.

Use of dynamic MRI during swallowing to assess carotid artery invasion by neck metastasis

The effectiveness of dynamic MRI in evaluating the relationship between metastatic lymph nodes and the carotid artery was investigated.

Treatment Outcomes of Locally Advanced Squamous Cell Carcinoma of the Ethmoid Sinus Treated with Anterior Craniofacial Resection or Chemoradiotherapy

We retrospectively analyzed 14 patients with locally advanced squamous cell carcinoma of ethmoid sinus (LASCC-ES) for the feasibility of anterior craniofacial resection (ACFR). Ethmoid cancer treatment comprised alternating chemoradiotherapy (ALCRT; n = 1), concomitant radiotherapy and intra-arterial cisplatin (RADPLAT; n = 4) and ACFR (n = 9). The 3- and 5-year overall survival (OS) rates of patients were 47.6 and 39.6%, respectively. The 3-year local control (LC) rates of chemoradiotherapy (CRT; ALCRT and RADPLAT) (n = 5) and ACFR (n = 9) groups were 0 and 66.7% (p = 0.012), respectively. The 3-year progression-free survival (PFS) rate of the CRT and ACFR groups were 0 and 55.6% (p = 0.018), respectively. The 3-year OS rate of the CRT and ACFR groups were 0 and 76.2% (p = 0.005), respectively. Postoperative pathological examinations confirmed positive margins in 3 (33%) of 9 cases. The 3-year LC and PFS rates of cases (n = 3) with positive surgical margins were significantly poorer than those of cases (n = 6) with negative surgical margins. Although ACFR for LASCC-ES is a feasible treatment, cases with positive surgical margins were more prone to local relapse. Therefore, surgical safety margins should be thoroughly assessed.