Salvage skull base surgery after proton beam therapy for recurrent sinonasal malignancies: A retrospective study.

BACKGROUND: This study aimed to examine treatment outcomes and postoperative complications associated with salvage skull base surgery following radical proton beam therapy (PBT). METHODS: Nine patients who underwent salvage skull base surgery following curative PBT as the initial treatment at our institution between September 2002 and May 2023 were retrospectively reviewed. RESULTS: The cohort comprised four males and five females with a mean age of 48.1 years. The average proton dose administered during initial therapy was 68.5 Gy (relative biological effectiveness). Among the salvage surgeries, eight were anterior skull base surgeries, and one was an anterior middle skull base surgery. No local recurrences or perioperative deaths were observed. Postoperative complications occurred in three patients (33.3%), all experiencing surgical site infections, with one also having cerebrospinal fluid leakage. CONCLUSION: The study demonstrates that salvage skull base surgery after PBT effectively achieves local control and safety in patients with recurrent sinonasal malignancies.

Risk factors for late postoperative bleeding after partial glossectomy for tongue cancer.

BACKGROUND: Partial glossectomy is the most common procedure for early-stage tongue cancer. Although late postoperative bleeding occasionally occurs, the associated risk factors have not been adequately identified. AIMS/OBJECTIVES: We aimed to investigate the rate and risk factors for late postoperative bleeding after transoral partial glossectomy with or without neck dissection for tongue cancer at our institution. MATERIAL AND METHODS: We analysed 211 patients who had undergone transoral partial glossectomy between January 2016 and January 2023. The potential risk factors associated with late postoperative bleeding were investigated using univariate and multivariate logistic regression analyses. RESULTS: Of the 211 patients, 40 (19%) showed late postoperative bleeding, with 19 (9%) classified as grade IIIa (Clavien-Dindo classification). Regarding all grades, late postoperative bleeding was significantly higher in patients aged <70 years and in those with polyglycolic acid (PGA) sheets (p = .046 and .030, respectively). For grade ≥ IIIa, late postoperative bleeding was significantly higher in patients with a history of anticoagulant/platelet administration, a mucosal defect covered with fibrin glue and a PGA sheet (p = .045 and .026, respectively). CONCLUSIONS AND SIGNIFICANCE: The findings of this study suggest that primary closure decreases the frequency of late postoperative bleeding.

Clinicopathological Features of Buccal Squamous Cell Carcinoma with Focus on Patients Who Never Smoke and Never Drink.

Introduction Oral carcinoma has been reported at a substantial proportion in patients who never smoke and never drink. However, the proportion may vary by subsite and ethnicity. Objective We aimed to determine the clinicopathological features of buccal squamous cell carcinoma (SCC) in a Japanese population. Methods We retrospectively analyzed the records of patients diagnosed with buccal SCC at our institution from September 2002 to November 2015. We reviewed the gender, age, tumor status, treatment, smoking, alcohol drinking, multiple primary cancers, and prognosis of the patients. The overall and cause-specific survival rates were calculated, and the effects of clinicopathological variables were assessed by univariate analysis. Furthermore, the cause of death was evaluated. Results Among the 63 patients (men: 38; women: 25) included in the present study, 29 (46.0%) never smoked or drank. Women were almost 5 years older than men ( p = 0.014). The number of women in the group who never smoked or drank was disproportionately higher than that of those in the smoker or drinker groups ( p < 0.001). In total, 29 patients (46.0%) had 59 multiple primary cancers, including 26 oral cancers. Surgeries and radiotherapy were performed in 57 (90.5%) and 6 (9.5%) cases, respectively. The 5-year overall survival and disease-specific survival rates were 74.6 and 78.8%, respectively. Conclusion Our study confirms that buccal SCC may develop in older adult Japanese patients, especially in women who have never smoked or drank. These patients could be at risk for second primary malignancy.

Surgical Strategy for Squamous Cell Carcinoma of the External Auditory Canal: Management of Locally Advanced Cases with Skull Base Involvement.

Objective Surgical indications for advanced-stage squamous cell carcinoma (SCC) of the external auditory canal (EAC) are highly dependent on the skull base surgery team. The aim of this study was to evaluate the surgical outcomes in patients with SCC of the EAC and to clarify the surgical indication of far advanced cases using the T4 subclassification. Methods Patients with SCC of the EAC who underwent curative treatment from 2002 to 2021 at our hospital were retrospectively reviewed. Clinical and surgical results, including operative data, overall survival (OS), and disease-specific survival (DSS), were analyzed. To clarify the surgical indication for advanced-stage tumors, we proposed the T4 subclassification. Results In the 46 patients included in the study, 8 patients had T1 tumors, 10 had T2 tumor, 5 had T3 tumors, and 23 had T4 tumors. The 5-year DSS with T1, T2, T3, and T4 tumors were 100, 85.7, 100, and 61.7%, respectively. No prognostic impacts for margin status were found between the 5-year OS and DSS ( p = 0.23 and 0.13, respectively). Patients with far-advanced-stage (T4b) tumors were significantly associated with shorter DSS than those with early-stage (T1/T2) and advanced-stage (T3/T4a) tumors ( p = 0.007 and 0.03, respectively). Conclusion The present study focused on patients with SCC of the EAC at a university hospital over a period of 20 years, especially with skull base involvement, and a T4 subclassification was proposed. Complete tumor resection in an en bloc fashion could help achieve a good survival rate even in patients with locally advanced tumors.

Clinicopathological Features of Buccal Squamous Cell Carcinoma with Focus on Patients Who Never Smoke and Never Drink

Abstract Introduction Oral carcinoma has been reported at a substantial proportion in patients who never smoke and never drink. However, the proportion may vary by subsite and ethnicity. Objective We aimed to determine the clinicopathological features of buccal squamous cell carcinoma (SCC) in a Japanese population. Methods We retrospectively analyzed the records of patients diagnosed with buccal SCC at our institution from September 2002 to November 2015. We reviewed the gender, age, tumor status, treatment, smoking, alcohol drinking, multiple primary cancers, and prognosis of the patients. The overall and cause-specific survival rates were calculated, and the effects of clinicopathological variables were assessed by univariate analysis. Furthermore, the cause of death was evaluated. Results Among the 63 patients (men: 38; women: 25) included in the present study, 29 (46.0%) never smoked or drank. Women were almost 5 years older than men (p = 0.014). The number of women in the group who never smoked or drank was disproportionately higher than that of those in the smoker or drinker groups (p < 0.001). In total, 29 patients (46.0%) had 59 multiple primary cancers, including 26 oral cancers. Surgeries and radiotherapy were performed in 57 (90.5%) and 6 (9.5%) cases, respectively. The 5-year overall survival and disease-specific survival rates were 74.6 and 78.8%, respectively. Conclusion Our study confirms that buccal SCC may develop in older adult Japanese patients, especially in women who have never smoked or drank. These patients could be at risk for second primary malignancy.

Immunological and Genetic Characterization of Patients With Head and Neck Cancer who Developed Recurrence.

BACKGROUND/AIM: The recurrence rate of head and neck squamous cell carcinoma (HNSCC) remains high; thus the control of recurrence is a clinical problem to be challenged. To clarify the precise mechanism, specific immunological biomarkers responsible for recurrence were investigated. PATIENTS AND METHODS: The expression levels of immune response-associated and Shizuoka Cancer Center 820 cancer-associated genes, and genetic mutations from whole-exome sequencing were compared between HNSCC patients who developed recurrence (n=8) and HNSCC patients who did not develop recurrence (n=19) using a volcano plot analysis. Cytokine and epithelial-mesenchymal transition marker genes were analyzed using quantitative PCR. Tumor-infiltrating lymphocytes, immune checkpoint molecules, and human papilloma virus status were investigated using immunohistochemistry (IHC). RESULTS: Twenty-seven evaluable patients with HNSCCs received radiation therapy after surgery. Recurrence was identified in 8 patients. TP53 mutations tended to be higher in patients who developed recurrence than in those who did not develop recurrence (75% vs. 31.6%). Gene expression profiling showed the down-regulation of T cell activation genes (ICOS, CD69 and CD83) and the upregulation of the ERBB4, EGFR, VEGF, HIF1A, TGFB1, TWIST1, IL-8, and PAX7 genes, which suggested the activation of the TP53 mutation-TGF-ß1-PAX7 pathway and epithelial-mesenchymal transition. Additionally, IHC indicated a tendency toward a reduction in T cell accumulation and an increase in M2-type macrophage infiltration in tumors that recurred. CONCLUSION: A TP53 mutation-mediated immune-suppressive state in the tumor microenvironment and TGF-ß1-PAX7-mediated EMT might contribute to the promotion of recurrence in patients with HNSCC after postoperative radiotherapy.

Lymph node ratio as a predictor for minor salivary gland cancer in head and neck.

BACKGROUND: We investigate whether pathological continuous variables of lymph nodes were related with survival results of carcinomas of minor salivary gland carcinoma in head and neck. METHODS: Forty-four cases with minor salivary gland carcinoma who underwent both primary resection and neck dissection were retrospectively enrolled. The pathological continuous variables were evaluated by the number of positive lymph nodes, lymph node ratio, and log odds of positive lymph nodes. Receiver operating curve analysis was used for the cut-off values of the carcinoma-specific death. Log-rank test and Cox's proportional hazards model were used for uni-/multi-variate survival analyses adjusting for pathological stage, respectively. RESULTS: Lymph node ratio = 0.05 as well as log odds of positive lymph nodes = - 2.73 predicted the carcinoma-specific death. Both lymph node ratio and log odds of positive lymph nodes were significantly related with survival outcomes by the univariate analysis. Lymph node ratio ≥ 0.05 was associated with shorter disease-specific (hazard ratio = 7.90, 95% confidence interval = 1.54-57.1), disease-free (hazard ratio = 4.15, 95% confidence interval = 1.48-11.2) and overall (hazard ratio = 4.84, 95% confidence interval = 1.05-24.8) survival in the multivariate analysis. CONCLUSION: A higher lymph node ratio of minor salivary gland carcinoma is a predictor of shorter survival results.

Safety and Efficacy of Salvage Neck Dissection Following Carbon-ion Radiotherapy with Chemotherapy for a Patient with Mucosal Malignant Melanoma of Head and Neck.

Mucosal malignant melanoma of the head and neck is a rare diagnosis. The safety and efficacy of salvage neck dissection following carbon-ion radiotherapy with concurrent chemotherapy are not well described, and carbon-ion radiation protocols have not been fully developed. A 77 year old woman with crT0N1M0 mucosal melanoma of the head and neck achieved a complete response following initial treatment with carbon-ion radiotherapy and concurrent chemotherapy. She was treated with salvage neck dissection for as a cervical lymph node metastasis 16 months after initial treatment. She experienced neither Clavien-Dindo Grade 3 or 4 postoperative complications nor subsequent recurrence of disease at 3 months following salvage neck dissection. Surgical specimens may be useful for future precision oncology based on the molecular biology of recurrence melanoma with poor prognosis.

P-class pentatricopeptide repeat protein PTSF1 is required for splicing of the plastid pre-tRNA(I) (le) in Physcomitrella patens.

Pentatricopeptide repeat (PPR) proteins are widely distributed in eukaryotes and are mostly localized in mitochondria or plastids. PPR proteins play essential roles in various RNA processing steps in organelles; however, the function of the majority of PPR proteins remains unknown. To examine the function of plastid PPR proteins, PpPPR_4 gene knock-out mutants were characterized in Physcomitrella patens. The knock-out mosses displayed severe growth retardation and reduced effective quantum yield of photosystem II. Immunoblot analysis showed that knock-out of PpPPR_4 resulted in a strongly reduced level of plastid-encoded proteins, such as photosystem II reaction center protein D1, the ß subunit of ATP synthase, and the stromal enzyme, Rubisco. To further investigate whether knock-out of the PpPPR_4 gene affects plastid gene expression, we analyzed steady-state transcript levels of protein- and rRNA-coding genes by quantitative RT-PCR. This analysis showed that the level of many protein-coding transcripts increased in the mutants. In contrast, splicing of a spacer tRNA(I) (le) precursor encoded by the rrn operon was specifically impaired in the mutants, whereas the accumulation of other plastid tRNAs and rRNAs was not largely affected. Thus, the defect in tRNA(I) (le) splicing leads to a considerable reduction of mature tRNA(I) (le) , which may be accountable for the reduced protein level. An RNA mobility shift assay showed that the recombinant PpPPR_4 bound preferentially to domain III of the tRNA(I) (le) group-II intron. These results provide evidence that PpPPR_4 functions in RNA splicing of the tRNA(I) (le) intron, and hence PpPPR_4 was named plastid tRNA splicing factor 1 (PTSF1).