Soon-Hyun Ahn

Objectives: Total parotidectomy (TP) has been advocated to ensure complete tumor clearance and removal of intraparotid lymph nodes; however, less‐than‐total parotidectomy (LTT) may offer comparable oncologic control with superior functional outcomes. In this systematic review and meta‐analysis, we compared oncologic and functional outcomes between LTT and TP for patients with T1–2 low‐grade parotid malignancies. Methods: A systematic literature search was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses guidelines. Four retrospective cohort studies of T1–2 low‐grade parotid cancer were included. Patients underwent either LTT or TP. Primary outcomes were overall survival (OS) and recurrence‐free survival (RFS). Pooled hazard ratios with 95% confidence intervals were calculated using random‐effects models. Heterogeneity was assessed using I ² statistics and the Cochran's Q test. Results: The pooled analysis demonstrated no significant difference in OS between LTT and TP based on three studies. Across the four studies, RFS was comparable between the two surgical approaches, and statistical heterogeneity was negligible for both OS and RFS. No evidence of publication bias was detected. Conclusion: In selected patients with T1–2 low‐grade parotid malignancies confined to the superficial lobe, LTT showed no statistically significant disadvantage in OS or RFS compared with TP based on the available retrospective evidence. However, the high risk of bias across included studies limits causal interprettion. Surgical strategy should therefore be individualized and should prioritize negative margins and functional preservation when oncologically appropriate. Prospective studies with standardized oncologic and functional outcome reporting are warranted. Level of Evidence: 3.

Intraoperative monitoring systems play a vital role in surgical safety and decision-making. This study explored whether high-resolution physiological signals routinely available during surgery can be leveraged by deep learning to predict adverse events after head and neck free flap reconstruction. In this retrospective study, intraoperative waveforms, including arterial pressure, plethysmography, and electrocardiogram, from 187 patients who underwent free flap surgery were analyzed. A deep learning model based on the Mamba architecture was trained to predict three outcomes: flap failure, return to the operating room for exploration, and other surgical complications. Conventional logistic regression using static clinical variables and feature-based machine learning models were evaluated for comparison. On a patient-wise stratified held-out test set, the deep learning model achieved AUROCs of 0.86, 0.62, and 0.93 for flap failure, re-exploration, and other complications, respectively. Precision was 0.50, 0.40, and 1.00, whereas recall was 0.50, 0.40, and 0.25, indicating high precision but modest recall. Predictive performance varied across outcomes. These findings demonstrate the feasibility of waveform-based deep learning for perioperative risk stratification in reconstructive surgery, although the preliminary nature, limited sample size, and lack of external validation should be considered.

Objectives. Differentiated thyroid cancer (DTC) has a favorable prognosis. However, indeterminate lymph nodes (LNs) are common, making it challenging to distinguish recurrent from persistent DTC. Previous studies have not specifically compared the prognosis between recurrent and persistent DTC. Therefore, we aimed to compare prognosis and oncologic characteristics between these two groups.Methods. This retrospective cohort study was conducted at a single tertiary care institution and included 265 patients with DTC (recurrent, 109; persistent, 156) who underwent reoperation between November 1, 1999, and August 31, 2018, for structural disease. Patients with distant metastasis at the time of initial diagnosis were excluded. Clinical and oncological characteristics, patterns of LN metastasis, disease-free survival (DFS), and overall survival (OS) were compared between the two groups. For DFS, time zero was defined as the date of the second operation.Results. Recurrent DTC had a higher incidence of central LN metastasis (P=0.003), infield recurrence (P<0.001), and distant metastasis (P<0.001). In contrast, persistent DTC more frequently exhibited lateral LN metastasis (P=0.003) and outfield recurrence (P<0.001). The most common site of neck LN metastasis was ipsilateral level VI/VII (51.4%) in recurrent DTC and ipsilateral level IV (43.0%) in persistent DTC. Ten-year DFS was significantly lower in recurrent DTC than in persistent DTC (41.0% vs. 67.9%; P<0.001). Recurrent DTC, older age, a higher number of metastatic LNs at the second operation (first reoperation), and R1/R2 resection at the second operation were associated with decreased DFS. OS did not significantly differ between recurrent and persistent DTC (P=0.160).Conclusion. Recurrent DTC is associated with poorer DFS than persistent DTC, although OS does not significantly differ between the two groups.

Objectives: Research on detected distant metastasis or anaplastic transformation in recurrent/persistent differentiated thyroid cancer is limited. We analyzed the clinical factors associated with detected distant metastasis or anaplastic transformation following reoperation for differentiated thyroid cancer.Methods: This retrospective review included 336 patients who underwent reoperation for differentiated thyroid cancer with detection of distant metastasis or anaplastic transformation following reoperation. The hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated.Results: Distant metastasis was detected in 45 patients (45/336, 13.4%) after reoperation. The risk of distant metastasis was higher for patients of male sex (adjusted HR: 2.373; 95% CI: 1.133–4.973), age ≥ 55 (adjusted HR: 4.991; 95% CI: 2.451–10.165), initial T3‐4 stage (adjusted HR: 2.347; 95% CI: 1.035–5.321), in‐field recurrence (adjusted HR: 3.267; 95% CI: 1.489–7.168), and those who had undergone ≥ 3 reoperations (adjusted HR: 3.378; 95% CI: 1.248–9.174). Anaplastic transformation was detected in 7 patients (7/336, 2.1%) after reoperation. The risk of anaplastic transformation was higher for patients with an age ≥ 55 (adjusted HR: 6.811; 95% CI: 1.300–35.676) and those who had undergone ≥ 3 reoperations (adjusted HR: 5.672; 95% CI: 1.139–28.236).Conclusion: In recurrent/persistent differentiated thyroid cancer, distant metastasis or anaplastic transformation following reoperation is not insignificant. There may be increased risk of distant metastasis or anaplastic transformation with multiple reoperations in patients who are men, aged ≥ 55, or at the initial T3–T4 stage.Level of Evidence: 4.

Purpose: First branchial cleft anomalies (FBCAs) are infrequent congenital malformations. In FBCAs removal surgery, due to the previous infection history and the anatomical proximity of the FBCAs tract to the facial nerve, postoperative recurrence and facial paralysis are not uncommon. This study aimed to assess the clinical feasibility and outcomes of FBCAs resection using the retrograde facial nerve dissection technique. Methods: This retrospective study included 19 patients (mean age, 6.3 ± 4.4 years) who underwent FBCAs excision via retrograde facial nerve dissection between 2017 and 2023. Data on demographics, operative details, histopathology, postoperative complications, and follow-up survey were reviewed. Results: Preoperative infection history was present in 94.7% of patients; 42.1% had prior incision and drainage and 15.8% had previous excision attempts. Complete resection was achieved in all cases without facial nerve palsy. No recurrence was observed during the follow-up periods (median, 23.9 ± 9.8 months). Postoperative pain and paresthesia showed clinical improvement, while cosmetic satisfaction was relatively limited. Conclusion: In FBCAs patients, the close proximity of the facial nerve and the adhesion between the tract and facial nerve pose significant challenges. Using retrograde facial nerve dissection is believed to enable complete removal and reduce postoperative facial nerve paralysis.

Objectives. Salivary gland tumors present a diagnostic challenge, with preoperative false-negative results frequently leading to an unexpected diagnosis of malignancy after parotidectomy. This study was conducted to explore the clinical utility of preoperative core needle biopsy (CNB) in diagnosing malignancies before primary parotidectomy and to assess the prognostic implications of CNB for parotid gland cancers.Methods. This retrospective cohort study included 615 patients who underwent preoperative CNB and parotidectomy for primary parotid tumors from 2003 to 2023 at a tertiary referral hospital. Among these patients, 102 who were diagnosed with primary parotid malignancy following parotidectomy were examined regarding survival outcomes. Disease-free survival (DFS) and predictive factors were assessed through univariable and multivariable analyses. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy of CNB were determined. These metrics were then compared to those of a separate cohort of 547 patients who underwent ultrasound-guided fine needle aspiration (FNA) and parotidectomy within the same timeframe.Results. In the CNB group, the 5-year predicted DFS was 86.9% (95% CI, 79.2%–95.3%). Multivariable analysis identified male sex (hazard ratio [HR], 8.48; 95% CI, 1.05–68.76) and a CNB finding of malignancy (HR, 8.20; 95% CI, 1.01–66.15) as factors significantly associated with decreased DFS. CNB demonstrated significantly higher sensitivity (89.0%; 95% CI, 81.2%–94.4%) and NPV (97.6%; 95% CI, 95.7%–98.8%) compared to FNA, which had a sensitivity of 45.2% (95% CI, 33.5%–57.3%) and an NPV of 90.8% (95% CI, 87.7%–93.3%).Conclusion. Preoperative CNB may be predictive of parotid cancer prognosis. Patients receiving a diagnosis of malignancy on preoperative CNB demonstrated a worse prognosis compared to those with a “less-than-malignant” diagnosis. Additionally, CNB exhibited higher sensitivity than FNA in identifying malignancies of the parotid gland.

The relationship between tumor microenvironments (TMEs) of regional lymph node metastases (LNMs) and primary tumors in head and neck squamous cell carcinoma (HNSCC) remains unclear. This study compared tumor-infiltrating lymphocytes (TILs) and the immune phenotype (IP), characterized by spatial TIL distribution, between primary tumors and LNMs. Twenty-one HNSCC patients with regional LNM who received immune checkpoint inhibitors (ICIs) were included. A paired comparative analysis of TIL densities and IP between primary tumors and LNMs revealed no significant difference or correlation between TIL densities in primary tumors and LNMs. Their IPs were discordant in 12 patients (57.1%). Patients with high intratumoral TIL exhibited longer progression-free survival (PFS) than those with low intratumoral TIL in both primary tumors (median, 5.2 vs. 1.3 months, p = 0.003) and LNMs (median, 30.2 vs. 1.3 months, p = 0.012). Patients with inflamed IP exhibited longer PFS than those with non-inflamed IP in both primary tumors (median, 4.5 vs. 1.3 months, p = 0.043) and LNMs (median, 4.1 vs. 1.3 months, p = 0.037). Given the lack of correlation in TIL densities, the discrepancies in IP, and the predictive value of both TMEs, evaluating the TMEs of both primary tumors and LNMs may be beneficial for the precise use of ICIs in HNSCC. There was a significant discordance between the TME of primary tumors and LNMs, with implications in survival outcomes. Therefore, evaluating the TME of both the primary tumor and LNM could be beneficial for the precise use of ICIs in HNSCC.

Background: This study evaluates functional larynx preservation in patients with hypopharyngeal cancer (HPC) and laryngeal cancer (LC) who achieved complete remission following radiotherapy (RT) or concurrent chemoradiation (CCRT).Methods: HPC and LC patients treated with RT/CCRT from 1999 to 2017 were retrospectively analyzed. Severe late dysphagia and tracheostomy cases were assessed to determine laryngeal function. Long‐term preservation rate of functional larynx and associated factors were evaluated.Results: Of 152 patients (55 HPC, 97 LC), nine developed severe dysphagia, occurring on average 58.2 months post‐treatment. HPC and cervical node metastasis significantly increased the risk of laryngeal function impairment (p < 0.001 and p = 0.014, respectively), presenting a continued decline in functional larynx preservation rate beyond 10 years.Conclusions: Patients with HPC and cervical node metastasis demonstrate an increased risk for long‐term laryngeal function impairment despite successful oncologic outcomes. This risk extends beyond 10 years, underscoring the need for prolonged monitoring and comprehensive support.

Objectives. Facial nerve sacrifice during radical parotidectomy can impair quality of life. This study assessed the effectiveness of single-stage facial reanimation surgery performed concurrently with radical parotidectomy in restoring facial function.Methods. A retrospective analysis was conducted on patients who underwent single-stage facial reanimation combined with radical parotidectomy. The techniques employed included selective reinnervation and orthodromic temporalis tendon transfer. Outcomes were evaluated using the modified House-Brackmann and Terzis grading systems, Emotrics facial assessment, and the Facial Disability Index (FDI).Results. Among the 13 patients studied (median age, 54 years; 69% male), 10 underwent selective reinnervation. Of these, nine patients demonstrated improvement, achieving House-Brackmann grade III and Terzis grade 4 or 5. The other three patients underwent tendon transfer and achieved moderate functional outcomes. Emotrics analysis revealed balanced facial symmetry in the selective reinnervation group. Furthermore, FDI scores indicated satisfactory physical and social/well-being functions.Conclusion. Single-stage facial reanimation effectively restores facial function in patients undergoing radical parotidectomy. This approach offers meaningful benefits in the early recovery of facial function.

Background: Despite the diverse genetic mutations in head and neck cancer, the chemotherapy outcome for this cancer has not improved for decades. It is urgent to select prognostic factors and therapeutic targets for oropharyngeal cancer to establish precision medicine. Recent studies have identified PSMD1 as a potential prognostic marker in several cancers. We aimed to assess the prognostic significance of PSMD1 expression in oropharyngeal squamous cell carcinoma (OPSCC) patients using immunohistochemistry. Methods: We studied 64 individuals with OPSCC tissue from surgery at Seoul National University Bundang Hospital between April 2008 and August 2017. Immunostaining analysis was conducted on the tissue microarray (TMA) sections (4 μm) for p16 and PSMD1. H-score, which scale from 0 to 300, was calculated from each nucleus, cytoplasm, and cellular expression. Clinicopathological data were compared with Chi-squared test, Fisher’s exact test, t-test, and logistic regression. Survival data until 2021 were achieved from national statistical office of Korea. Kaplan–Meier method and cox-regression model were used for disease-specific survival (DSS) analysis. Results: H-score of 90 in nucleus was appropriate cutoff value for ‘High PSMD1 expression’ in OPSCC. Tonsil was more frequent location in low PSMD1 group (42/52, 80.8%) than in high PSMD1 group (4/12, 33.3%; P = .002). Early-stage tumor was more frequent in in low PSMD1 group (45/52, 86.5%) than in high PSMD1 group (6/12, 50%; P = .005). HPV was more positive in low PSMD1 group (43/52, 82.7%) than in high PSMD1 group (5/12, 41.7%; P = .016). Patients with PSMD1 high expression showed poorer DSS than in patients with PSMD1 low expression (P = .006 in log rank test). In multivariate analysis, PSMD1 expression, pathologic T staging, and specimen age were found to be associated with DSS (P = .011, P = .025, P = .029, respectively). Conclusions: In our study, we established PSMD1 as a negative prognostic factor in oropharyngeal squamous cell carcinoma, indicating its potential as a target for targeted therapy and paving the way for future in vitro studies on drug repositioning.