Induction of Immunological Antitumor Effects by the Combination of Adenovirus-Mediated Gene Transfer of B7-1 and Anti-Programmed Cell Death-1 Antibody in a Murine Squamous Cell Carcinoma Model

BACKGROUND

The goal of this study was to evaluate the antitumor immune effects of B7-1 gene expression in addition to immune checkpoint inhibitor against squamous cell carcinoma.

METHODS

A murine SCC cell line, KLN205, was infected with adenoviral vector carrying B7-1 (AdB7). Infected cells were injected subcutaneously in the flanks of DBA/2 mice. Three weeks after implantation, anti-mouse PD-1 antibody (antiPD1) was intraperitonially administrated twice a week for a total of six times.

RESULTS

CD80 was significantly overexpressed in the AdB7-infected tumors. IFN-gamma in the T cells in the spleen was significantly increased and tumor size was significantly reduced in the mice treated with both AdB7 and antiPD1. Targeted tumors treated with both AdB7 and antiPD1 exhibited significantly increased cell densities of total immune cells as well as Ki-67+ CD8+ T cells and decreased regulatory T cells.

CONCLUSIONS

These results suggest that the B7-1 gene transfer may enhance the antitumor effect of anti-PD1 antibody against SCC.

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.

Oncological outcomes of concurrent chemoradiotherapy with docetaxel, cisplatin, and 5-fluorouracil for locally advanced squamous cell carcinoma of the external auditory canal: A single-center study

BACKGROUND

Squamous cell carcinoma of the external auditory canal (EACSCC) is a rare condition. However, a standard treatment has not yet been established. We retrospectively evaluated the efficacy, adverse events, and feasibility of TPF-CCRT (concomitant chemoradiotherapy with docetaxel, cisplatin, and 5-fluorouracil) in patients with advanced EACSCC.

METHODS

Thirty-five consecutive patients with advanced EACSCC (T3, T4) initially treated with TPF-CCRT at Kobe University Hospital were included. T4 diseases with invasion of the brain, internal carotid artery, or internal jugular vein were classified as T4b, and those without these features were classified as T4a.

RESULTS

Five-year overall survival rates for T3 and T4 were 100% and 64.2%, respectively. A significant difference was observed between T4a and T4b (82.4% vs. 30%, p = 0.007). Five-year progression-free survival rates of T3, T4a, and T4b were 100%, 68%, and 20% (p = 0.022), respectively.

CONCLUSIONS

TPF-CCRT should be considered as a plausible treatment option for advanced EACSCC.

Prognostic scores for patients with salivary adenoid cystic carcinoma without lymph node metastasis

Adenoid cystic carcinoma (AdCC) of salivary gland grows relatively slowly, but occasionally develops distant metastasis. Although cervical lymph node metastasis (LNM) has been reported as a strong prognostic factor, most of AdCC do not have LNM. In this study, we investigated the prognostic factors to predict disease free survival (DFS), distant metastasis free survival (DMFS), and overall survival (OS) for 175 patients surgically treated for AdCC without LNM, and developed prognostic score (PS) determined as number of positive prognostic factors. The following emerged as significant prognostic factors: positive surgical margin in DFS, pT3/4 and positive surgical margin in DMFS, and positive surgical margin and high-histological grade in OS. 10-year DFS rates were 56.4% in PS0, and 19.1% in PS1 (p < 0.0001). 10-year DMFS rates were 86.3% in PS0, 56.4% in PS1, and 30.7% in PS2 (p < 0.0001). 10-year OS rates were 100% in PS0, 73.3% in PS1, and 38.8% in PS2 (p < 0.0001).

Incidence and spread pattern of lymph node metastasis from submandibular gland cancer

OBJECTIVES

To clarify the indication of neck dissection (ND) for patient with submandibular gland (SMG) cancer.

METHODS

A total of 43 patients with SMG cancer were retrospectively analyzed. Forty-one patients underwent ND: Levels I-V in 19 patients, Levels I-III in 18 patients, and Level Ib in 4 patients. The other two patients did not undergo ND, since preoperative diagnoses were benign. Postoperative radiotherapy was performed in 19 patients with positive surgical margin, high grade cancer or stage IV disease.

RESULTS

LN metastases were pathologically confirmed in all patients with cN + and 6 out of 31 patients with cN-. No patients developed regional recurrence during follow-up periods. Ultimately, LN metastases were pathologically confirmed in 17 of 27 high grade, one out of 9 intermediate grade, but not in 7 low grade.

CONCLUSIONS

Prophylactic neck dissection should be considered in T3/4 and high grade SMG cancers.

OK432 sclerotherapy for refractory chylous leakage after neck dissection

Chylous leakage is a rare but serious postoperative complication of neck dissection (ND). Most chylous leakages are successfully treated either by drainage or ligation of the thoracic duct, but the resolution is occasionally prolonged. OK432 sclerotherapy is used to treat various refractory cystic diseases of the head and neck. Three patients were treated with OK432 sclerotherapy for refractory chylous leakage following ND. Case 1 involved a 77-year-old man with chylous leakage after a total laryngectomy and bilateral ND. Case 2 involved a 71-year-old woman who underwent total thyroidectomy and left ND for thyroid cancer. Case 3 involved a 61-year-old woman who underwent right ND for oropharyngeal cancer. In all patients, chylous leakage rapidly improved after OK432 injection without any complications. Our results suggest the efficacy of OK432 sclerotherapy in patients with refractory chylous leakage after ND.

Ligation of the ethmoid arteries in superselective intra-arterial infusion of cisplatin for advanced maxillary sinus cancer fed by the ophthalmic artery

BACKGROUND

Superselective cisplatin (CDDP) infusion via the external carotid artery system and concomitant radiotherapy (RADPLAT) provides favorable oncological and functional outcomes in patients with maxillary sinus cancer. However, targeted lesions are occasionally fed by the branch of the internal carotid artery.

METHODS

In RADPLAT for maxillary sinus cancer partly fed by the ophthalmic artery, the ethmoid arteries were ligated in two patients without medial orbital wall involvement. In four patients with that, CDDP was administered via the ophthalmic artery.

RESULTS

A complete response was obtained in all six patients. Locoregional recurrence was not observed in any cases. However, visual acuity was lost in four patients who received the ophthalmic artery infusion.

CONCLUSIONS

Ligation of the ethmoid arteries is recommended in RADPLAT for maxillary sinus cancer with lesions fed by the ophthalmic artery. CDDP administered via the ophthalmic artery may be considered if a patient accepts the possibility of visual loss.

Search for Gamma-Ray Spectral Lines from Dark Matter Annihilation up to 100 TeV toward the Galactic Center with MAGIC

Linelike features in TeV γ rays constitute a "smoking gun" for TeV-scale particle dark matter and new physics. Probing the Galactic Center region with ground-based Cherenkov telescopes enables the search for TeV spectral features in immediate association with a dense dark matter reservoir at a sensitivity out of reach for satellite γ-ray detectors, and direct detection and collider experiments. We report on 223 hours of observations of the Galactic Center region with the MAGIC stereoscopic telescope system reaching γ-ray energies up to 100 TeV. We improved the sensitivity to spectral lines at high energies using large-zenith-angle observations and a novel background modeling method within a maximum-likelihood analysis in the energy domain. No linelike spectral feature is found in our analysis. Therefore, we constrain the cross section for dark matter annihilation into two photons to ⟨σv⟩≲5×10^{-28}  cm^{3} s^{-1} at 1 TeV and ⟨σv⟩≲1×10^{-25}  cm^{3} s^{-1} at 100 TeV, achieving the best limits to date for a dark matter mass above 20 TeV and a cuspy dark matter profile at the Galactic Center. Finally, we use the derived limits for both cuspy and cored dark matter profiles to constrain supersymmetric wino models.

Expressions of NeuroD and GAP43 as diagnostic markers for olfactory neuroblastoma

OBJECTIVE

Olfactory neuroblastoma (ONB) is often difficult to pathologically distinguish from other small round cell tumors (SRCTs) arising in the nasal cavities. Although there are several diagnostic markers used for differential diagnosis of ONB, these molecules are also expressed in various neuronal derived tumors. Here, we examined the expression of NeuroD, GAP43, and olfactory marker protein (OMP) in ONB and non-ONB SRCT to determine their utility in the differential diagnosis of ONB.

METHODS

Twenty-six patients diagnosed with and treated for ONB at Kobe University Hospital between 1997 and 2017 with formalin-fixed, paraffin-embedded biopsy or surgical resection specimens were included. The expressions of NeuroD, GAP43, and OMP were immunohistochemically examined in these 26 ONB specimens and specimens from 13 SRCTs arising in the nasal cavities for reference.

RESULTS

Among the 26 ONB samples, focal, patchy, and marked staining for NeuroD was observed in 4, 3, and 9 samples, respectively. Focal, patchy, and marked GAP43 staining was observed in 5, 3, and 11 samples, respectively. Consequently, marked positive staining for either NeuroD or GAP43 was observed in 54% (14/26) of ONBs. Among the 13 SRCTs, marked staining for NeuroD was observed in two small cell carcinomas, one undifferentiated carcinoma, and one neuroendocrine carcinoma, whereas marked positive staining for GAP43 was observed only in one undifferentiated carcinoma. No specimen in this study exhibited OMP staining.

CONCLUSIONS

Our results suggest possible roles of GAP43 immunostaining in the differential diagnosis of ONB.

Intraoperative quantitative assessment of parathyroid blood flow during total thyroidectomy using indocyanine green fluorescence imaging ‐ surgical strategies for preserving the function of parathyroid glands

Objective

We investigated the factors affecting postoperative parathyroid gland (PTG) function and devised an objective index to predict the postoperative PTG function during total thyroidectomy.

Method

This was a retrospective clinical review of 21 consecutive patients who were diagnosed with papillary thyroid carcinoma and underwent total thyroidectomy. The maximum intensity ratio (MIR) was determined as the maximum fluorescence intensity after ICG injection divided by the intensity before ICG injection.

Results

Postoperative hypoparathyroidism is significantly associated with simultaneous central neck dissection (CND) and lateral neck dissection (LND) (p = .032). The Spearman correlation test showed a moderate correlation between the MIR and iPTH levels (p = .0047). The optimal MIR cutoff value for predicting postoperative hypoparathyroidism was 2.14 with area under the curve = 0.904 (sensitivity: 0.769 and specificity: 1.00).

Conclusion

CND + LND was significantly associated with postoperative hypoparathyroidism. MIR was found useful in predicting the postoperative PTG function.

Level of Evidence: 3b.

Abstract 6143: Tumor immune microenvironment in salivary gland cancer

Purpose/Objectives: Salivary gland cancer (SGC) is a rare malignancy with various pathological types. Although immune checkpoint inhibitors for SGC have been investigated in clinical trials, details of the tumor immune microenvironment (TIME) in SGC remain unclear. The aim of this study was to elucidate the TIME of SGC.

Materials/Methods: We selected five typical pathological types of SGC, namely adenoid cystic carcinoma (ACC); adenocarcinoma, not otherwise specified (ANOS); salivary duct carcinoma (SDC); and low/high-grade mucoepidermoid carcinoma (MEC low/high). We investigated the TIME as well as the tumor mutation burden (TMB) of each pathological type in surgical archival tissues obtained from 1999 to 2017 (7 patients in each type, stage III/IVA/IVB [UICC 8th]). TIME was evaluated by multiplexed immunofluorescent staining, including CD3, CD4, CD8, Foxp3, CD204, PD-1, PD-L1, and PD-L2. Tumors with &gt; 1% tumor cells expressing PD-L1 were considered positive for PD-L1. TMB was measured by the Oncomine Tumor Mutation Load Assay, and a high TMB was defined by 10 or more mutations/Mb. Correlation analyses were performed using Pearson’s product moment correlation coefficient.

Results: Multiplexed immunofluorescent staining was performed in all 35 archival tissues. ACC showed the lowest infiltration of immune effector cells (ICeff) and suppressor cells (ICsup) in both the tumor and stroma, and a low proportion of cases was positive for PD-L1 (14%). Compared with ACC, MEC high showed higher infiltration of ICeff and ICsup in both the tumor and stroma, and a higher proportion of cases was positive for PD-L1 (71%). Although ANOS, SDC, and MEC low showed modest infiltration of ICeff in the tumor, these subtypes showed higher infiltration of ICeff in the stroma than ACC. TMB was measured in 29 samples; the proportion of TMB high was lower in ACC (33%) and MEC low (0%) than in the other pathological types (ANOS/SDC/MEC high: 60/67/57%). Regarding multiplexed immunofluorescent staining, correlation analysis showed a positive correlation between TMB and CD3+CD8+ T cells in the tumor (r=0.647, P&lt;0.0001). In addition, CD3+CD8+ T cells in the tumor showed a positive correlation with PD-L1 expression in tumor cells (r=0.513, P=0.002) and with CD3+CD4+Foxp3+ T cells in the tumor (r=0.399, P=0.018). However, no correlation was seen between CD3+CD8+ T cells and CD204+ cells in the tumor (r=-0.049, P=0.779).

Conclusion: ACC showed less PD-L1 expression in tumor cells and the lowest infiltration of immune cells in both the tumor and stroma compared with other pathological types. These results suggest that the TIME of ACC is the so-called immune desert type, which may in turn explain the mechanisms of the poor response to immune check point inhibitors seen in clinical trials.

Citation Format: Yoshiaki Nagatani, Naomi Kiyota, Yoshinori Imamura, Taiji Koyama, Yohei Funakoshi, Masato Komatsu, Masanori Teshima, Ken-Ichi Nibu, Kazuko Sakai, Kazuto Nishio, Manami Shimomura, Tetsuya Nakatsura, Daiki Ikarashi, Takayuki Nakayama, Shigehisa Kitano, Hironobu Minami. Tumor immune microenvironment in salivary gland cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 6143.

Roles of skull base surgery and particle radiotherapy for orbital malignant tumors involving the skull base

PURPOSE

To investigate the oncological outcomes of orbital malignant tumors invading the skull base.

METHODS

A retrospective analysis was conducted on 16 patients with orbital malignant tumors invading the skull base. Eleven patients were treated with skull base surgery, four patients were treated with particle therapies, and one patient was treated with chemoradiotherapy (CRT) as initial treatment.

RESULTS

The most frequent histological type was adenoid cystic carcinoma in seven patients, followed by squamous cell carcinoma in two patients. Local recurrence occurred in two of the six surgically treated patients who did not receive postoperative radiotherapy (RT) or CRT. One of them was successfully salvaged by RT, and the other died of disease. With a median follow-up of 24 months, the 2-year overall, local control, and disease-free survival rates of all patients were 82.5%, 87.5%, and 59%, respectively.

CONCLUSIONS

Patients with positive surgical margins were at risk of local recurrence. Postoperative RT should be considered for all surgically treated patients.Level of Evidence: 4.

Blowing time ratio and high-resolution manometry to evaluate swallowing function of patients with oral and oropharyngeal cancer

OBJECTIVE

The blowing time ratio, which is the ratio of the blowing time when the nostrils are open and closed, is significantly correlated with velopharyngeal pressure, not only during speech but also during swallowing. This study aimed to further evaluate the usefulness of the blowing time ratio as a screening tool to evaluate the swallowing pressure of patients treated for oral and oropharyngeal cancers using high-resolution manometery (HRM).

METHODS

Ten patients treated for oral or oropharyngeal cancer were recruited for this study. Swallowing pressures at the velopharynx, oropharynx, and upper esophageal sphincter (UES) were measured using HRM. Their correlations with the blowing time ratio were analyzed.

RESULTS

The blowing time ratio was significantly correlated with the swallowing pressures of the oropharynx (CC = 0.815, p = 0.004) and the velopharynx (CC = 0.657, p = 0.039), but not of the UES.

CONCLUSIONS

The present results further support our previous finding that the blowing time ratio is a useful screening tool to evaluate velopharyngeal and oropharyngeal swallowing pressures in patients treated for oral and oropharyngeal cancer.

Prognostic factors after transoral resection of early hypopharyngeal cancer

OBJECTIVE

This study aimed to investigate risk factors predictive of local recurrence and/or lymph node metastasis after transoral resection of early hypopharyngeal cancer.

METHODS

Forty-nine consecutive patients who underwent transoral videolaryngoscopic surgery (TOVS) as an initial treatment for hypopharyngeal cancer were evaluated. On univariate and multivariate analysis, local recurrence rates were assessed respectively using log-rank test and cox regression analysis according to the following parameters: subsite, pT, mucosal margin, lymphatic invasion, vessel invasion, tumor thickness (> 4 mm vs ≤4 mm), history of esophageal cancer, and multiple Lugol-voiding lesions (LVLs) in the esophagus. Categorical variables were evaluated for their associations with lymph node metastasis using chi-squared test or Fisher's exact test.

RESULT

The subsites of primary lesions were piriform sinus in 24 patients, posterior wall in 15 patients, and postcricoid in 10 patients. Thirty patients had esophageal cancer. Local recurrence occurred in 14 patients. Three patients had lymph node metastasis at the time of diagnosis and four patients developed lymph node metastasis after the initial treatment, resulting a total of seven patients having lymph node metastasis. While mucosal margin and LVLs showed significant associations with local recurrence on univariate analysis, only LVLs remained as a significant risk factor on multivariate analysis (P = .0395; hazard ratio = 8.897; 95% confidence interval, 1.113-71.15). Most cases of local recurrence were satisfactorily controlled by repeated TOVS. While multivariate analysis could not be performed due to the small number of the patients with lymph node metastases, venous invasion (P = .0166) and tumor thickness (P = .0092) were significantly associated with lymph node metastasis on univariate analysis.

CONCLUSIONS

Local recurrence was more frequent in patients with LVLs, but most of them were salvaged by repeated TOVS. Patients with venous invasion and/or tumor thickness greater than 4 mm should be followed up with special attention to lymph node metastasis.Level of Evidence: 3.

Exploratory Analysis to Predict Optimal Tumor Burden for Starting Lenvatinib in Patients With Radioiodine-Refractory Differentiated Thyroid Cancer

Background

We previously reported that a high tumor burden is a prognostic factor based on an analysis of 26 patients with radioactive iodine-refractory differentiated thyroid cancer (RR-DTC) who were treated with lenvatinib. However, the optimal tumor burden for starting lenvatinib still remains to be defined. The aim of this retrospective study was to further explore in the same patient cohort the optimal timing for the start of lenvatinib by focusing on the pre- and post-treatment tumor burden.

Methods

The 26 patients were treated with lenvatinib from 2012 to 2017. We explored the optimal timing for the start of lenvatinib by comparing the characteristics of long-term responders who were defined as patients with progression-free survival ≥ 30 months and non-long-term responders.

Results

Long-term responders had a smaller post-treatment tumor burden at maximum shrinkage than non-long-term responders. Further, post-treatment tumor burden had a strong linear correlation with baseline tumor burden. We created an estimation formula for baseline tumor burden related to prognosis, using these regression lines. Patients with a sum of diameters of target lesions < 60 mm or maximum tumor diameter < 34 mm at baseline were estimated to have significantly better survival outcomes.

Conclusions

We found a strong linear correlation between pre- and post-treatment tumor burden. Our results suggested a cut-off value for baseline tumor burden for long-term prognosis among patients treated with lenvatinib.

Indications and Strategy for Active Surveillance of Adult Low-Risk Papillary Thyroid Microcarcinoma: Consensus Statements from the Japan Association of Endocrine Surgery Task Force on Management for Papillary Thyroid Microcarcinoma

Background: The question of how to manage patients with low-risk papillary thyroid microcarcinoma (PTMC; T1aN0M0) has recently become an important clinical issue. Two Japanese centers have conducted prospective clinical trials of active surveillance (AS) for low-risk PTMC since the 1990s, reporting favorable outcomes. This policy has thus seen gradual adoption worldwide to avoid overtreatment. Not all PTMCs are suitable for AS, however, and many physicians still hesitate to apply the management policy in daily clinical practice. A task force on management for PTMC created by the Japan Association of Endocrine Surgery collected and analyzed bibliographic evidence and has produced the present consensus statements regarding indications and concrete strategies for AS to facilitate the management of adult patients diagnosed with low-risk PTMC. Summary: These statements provide indications for AS in adult patients with T1aN0M0 low-risk PTMC. PTMCs with clinical lymph node metastasis, distant metastasis, recurrent laryngeal nerve (RLN) paralysis due to carcinoma invasion, or protrusion into the tracheal lumen warrant immediate surgery. Tumors suspected of aggressive subtypes on cytology are recommended for immediate surgery. Immediate surgery is also recommended for tumors adherent to the trachea or located along the course of the RLN. Practical strategies include diagnosis, decision-making, follow-up, and monitoring related to the implementation of AS. The rate of low-risk PTMC progression is lower in older patients. However, we recommend continuing AS as long as circumstances permit. Future tasks in optimizing management for low-risk PTMC are also described, including molecular markers and patient-reported outcomes. Conclusions: An appropriate multidisciplinary team is necessary to accurately evaluate primary tumors and lymph nodes at the beginning of and during AS, and to adequately reach a shared-decision with individual patients. If appropriately applied, AS of low-risk PTMC is a safe management strategy offering favorable outcomes and preserves quality of life at low cost.

Reconstruction of the external auditory canal using full-thickness rolled-up skin graft after lateral temporal bone resection for T1 and T2 external auditory canal cancer

OBJECTIVE

To present our results of the external auditory canal (EAC) reconstruction procedure using rolled-up full-thickness skin graft with tympanoplasty after lateral temporal bone resection (LTBR) for early-stage EAC carcinoma.

PATIENTS AND METHODS

A retrospective review of 15 patients who had undergone LTBR with reconstruction of the EAC for T1 and T2 EAC cancer between 2016 and 2020.

RESULTS

Postoperative mean air-bone gap was 30.7 decibel hearing level. Although a few patients experienced chronic granulation, persistent otorrhea, and/or laterization of the tympanic membrane, most patients showed no serious complications related to the EAC reconstruction.

CONCLUSION

EAC reconstruction using a full-thickness skin graft in combination with tympanoplasty is useful for minimizing the hearing loss, maintaining the cosmetic appearance, and facilitating the observation into the ear cavity.

Risk factors for osteoradionecrosis of the jaw in patients with head and neck squamous cell carcinoma

BACKGROUND

To evaluate factors associated with osteoradionecrosis of the jaw (ORNJ) in patients with head and neck squamous cell carcinoma (HNSCC), focusing on jaw-related dose-volume histogram (DVH) parameters.

METHODS

We retrospectively reviewed the medical records of 616 patients with HNSCC treated with curative-intent or postoperative radiation therapy (RT) during 2008-2018. Patient-related (age, sex, history of smoking or alcohol use, diabetes mellitus, performance status, pre-RT dental evaluation, pre- or post-RT tooth extraction), tumor-related (primary tumor site, T-stage, nodal status), and treatment-related (pre-RT surgery, pre-RT mandible surgery, induction or concurrent chemotherapy, RT technique) variables and DVH parameters (relative volumes of the jaw exposed to doses of 10 Gy-70 Gy [V10-70]) were investigated and compared between patients with and without ORNJ. The Mann-Whitney U test was used to compare RT dose parameters. Univariate and multivariate Cox regression analyses were used to assess factors associated with ORNJ development. Kaplan-Meier analyses were performed for cumulative ORNJ incidence estimation.

RESULTS

Forty-six patients (7.5%) developed ORNJ. The median follow-up duration was 40 (range 3-145) months. The median time to ORNJ development was 27 (range 2-127) months. DVH analysis revealed that V30-V70 values were significantly higher in patients with than in those without ORNJ. In univariate analyses, primary tumor site, pre-RT mandible surgery, post-RT tooth extraction, and V60 > 14% were identified as important factors. In multivariate analyses, V60 > 14% (p = 0.0065) and primary tumor site (p = 0.0059) remained significant. The 3-year cumulative ORNJ incidence rates were 2.5% and 8.6% in patients with V60 ≤ 14% and > 14%, respectively (p < 0.0001), and 9.3% and 1.4% in patients with oropharyngeal or oral cancer and other cancers, respectively (p < 0.0001).

CONCLUSIONS

V60 > 14% and oropharyngeal or oral cancer were found to be independent risk factors for ORNJ. These findings might be useful to minimize ORNJ incidence in HNSCC treated with curative RT.

Salvage surgery for structural local recurrence of papillary thyroid cancer: recurrence patterns and surgical outcome

To clarify the patterns of the recurrence and to assess the oncological and functional outcomes after salvage surgery for the patients with structural local recurrence of papillary thyroid cancer (PTC), twenty-five patients who underwent salvage surgery for structural local recurrence of PTC were retrospectively reviewed. Structural recurrences were observed in the tracheal lumen in 5 patients, intraluminal or intramuscular esophagus in 5 patients, trachea, and cricoid cartilage in 9 patients, cricoid and thyroid cartilage in 2 patients, intra-lumen of the larynx in 1 patient and soft tissue around thyroid in 3 patients, respectively. Although all local disease was resected with macroscopically negative margin, 10 patients diagnosed as microscopically positive margin. Major surgical complications occurred in 6 patients, including common carotid artery injury (n = 1), unintentional pharyngeal or esophageal injury (n = 2), recurrent laryngeal nerve paralysis (n = 2), and pharyngeal fistula resulting in common carotid artery rupture (n = 1), and were successfully managed. During the follow-up periods, 6 patients were alive without disease, 15 patients survived with distant metastases and/or locoregional recurrence, and 4 patients died of the disease. While tracheocutaneous fistula remained in 7 patients, the vocal function was preserved in all patients but one who underwent total laryngectomy. Normal oral intake was retained in all patients. In conclusion, although salvage surgery for structural recurrence of PTC has a high risk of complications, it may be worthwhile when macroscopic curative resection is available. The decision should be made considering various factors including curability, risk of surgical procedure, functional outcome, and life expectancy.

En Bloc Subtotal Temporal Bone Resection in a Case of Advanced Ear Cancer: 2-Dimensional Operative Video

Temporal bone cancer is extremely rare; thus, the optimal surgical strategy for advanced tumors, en bloc vs piecemeal resection, remain controversial. Some authors have favored piecemeal resection and reported comparable outcomes.1 Other authors recommend the use of en bloc subtotal temporal bone resection (STBR) for advanced tumors and reported better outcomes, although long-term cancer control remains uncertain.2 Because of the technical difficulty and the lack of demonstrative surgical videos, STBR has not been sufficiently distributed. This video demonstrates en bloc STBR in a stepwise manner with particular focus on the neurosurgeon's role and aims to improve its safety, feasibility, and distribution. This video conforms to the description of Osawa et al3 in the designations for each segment of the petrous ICA. A 67-yr-old man suffered from consistent otorrhea and underwent tympanoplasty at an outside hospital 1 yr earlier. Following a histopathological diagnosis of squamous cell carcinoma in the specimen, he underwent chemoradiotherapy (cisplatin + 70 Gy). However, a current imaging revealed a recurrent tumor and he was admitted to our hospital for radical resection. Computed tomography revealed a disrupted external auditory canal and magnetic resonance imaging indicated a carcinoma equivalent to Pittsburg stage T3. The patient underwent radical STBR without complications. His postoperative course was uneventful. At 2 yr postoperative, his modified Rankin scale score was 1, no recurrence was noted, and his facial nerve function was restored to House-Brackmann Grade IV. This video was reproduced with informed consent from the patient.

Two cases of glottic closure for refractory aspiration pneumonia after vertical partial laryngectomy

Vertical partial laryngectomy is a well-established surgical procedure for early glottic cancers with acceptable functional and oncological outcomes. However, on a long-term basis, aspiration might be a serious problem with aging. Here we presented two cases of refractory aspiration pneumonia after vertical laryngectomy. Case 1: A 76-year old gentleman with a past history of malignant lymphoma treated by chemotherapy and radiotherapy had glottic cancer, which was treated by repeated vertical partial laryngectomies. Although glottic caner had been well controlled, he started to suffer from refractory aspiration pneumonia. Since his cervical skin was very thin and hard and his general condition was poor, we employed modified Kano's method for glottic closure. Case 2: A 87-year old Japanese male had a past history of glottic cancer treated by radiotherapy and vertical partial laryngectomy. He was repeatedly hospitalized for severe aspiration pneumonia. At the age of 87, he had second primary oropharyngeal cancer. Kano's method was simultaneously performed at the time of resection of oropharyngeal cancer. Postoperative courses were uneventful without sign of leakage in both cases. The patients started oral intake 2 weeks after the surgery. They have been alive without aspiration pneumonia and takes normal diet.

Oncolytic effect of Midkine promoter-based conditionally replicating adenoviruses expressing EGFR siRNA in head and neck squamous cancer cell line T891

Background

Epidermal growth factor receptor (EGFR) is overexpressed in head and neck squamous cell carcinomas (HNSCCs). Midkine expression is restricted in adult tissues but is increased in several malignant tumors, including HNSCCs.

Aim

Here, we evaluated the antitumor effect of Midkine promoter–based conditionally replicative adenovirus expressing siRNA against EGFR for targeting HNSCCs expressing Midkine.

Methods and results

A conditionally replicative adenovirus vector controlled by the Midkine promoter, Ad‐MK‐siEGFR, was generated by integrating gene‐expressing siRNA against EGFR. Antitumor effect of Ad‐MK‐siEGFR was tested in vitro using established HNSCC cell line, T891 with strong Midkine expression. Expression of EGFR in T891 infected with Ad‐MK‐siEGFR was significantly lower than that of T891 infected with control. Cytotoxicity assays showed significant growth suppression of Ad‐MK‐siEGFR in T891 cells.

Conclusions

This study demonstrated the possibility of oncolytic therapy using the Midkine promoter–based conditional replication‐selective adenovirus containing siRNA against EGFR in HNSCC cell line T891. Further validation of the findings in more cell lines and in vivo should be performed to clarify the potential clinical application.

Bounds on Lorentz Invariance Violation from MAGIC Observation of GRB 190114C

On January 14, 2019, the Major Atmospheric Gamma Imaging Cherenkov telescopes detected GRB 190114C above 0.2 TeV, recording the most energetic photons ever observed from a gamma-ray burst. We use this unique observation to probe an energy dependence of the speed of light in vacuo for photons as predicted by several quantum gravity models. Based on a set of assumptions on the possible intrinsic spectral and temporal evolution, we obtain competitive lower limits on the quadratic leading order of speed of light modification.

Left non-recurrent inferior laryngeal nerve in a patient with right-sided aortic arch and aberrant left subclavian artery

Non-recurrent inferior laryngeal nerve (NRILN) is rare but one of the important anatomical variations in thyroid and parathyroid surgery. Almost all cases were observed on the right side with aberrant right subclavian artery and left NRILN have been reported in only five cases so far. Here, we reported a 38 year-old Japanese male with left NRILN accompanying adenomatous goiter. He was referred to our hospital for the surgical treatment of left thyroid goiter. Preoperative computed tomography revealed right-sided aortic arch and aberrant left subclavian artery with no signs of complete situs inversus viscerum, suggesting possible left NRLN. Left hemithyroidectomy was performed using nerve monitoring system. Intraoperatively, left recurrent laryngeal nerve was not identified along tracheoesophageal groove, but directly originated from vagal nerve and was running horizontally to larynx. Mobility of vocal cords were not impaired and postoperative course was uneventful. During thyroid surgery for the patients with right-sided aortic arch, meticulous care should be taken using nerve monitoring system to avoid nerve injury.

Extent of neck dissection for patients with clinical N1 oral cancer

BACKGROUND

No clear consensus has been reached on the indication of supraomohyoid neck dissection (SOHND) for clinically positive lymph-node metastasis.

PATIENTS

Consecutive 100 patients with previously untreated oral cancer treated at Kobe University Hospital were included in this study. All patients were clinically staged as anyTN1M0 and underwent radical dissection of the primary site and level I-V neck dissection as the initial treatment.

RESULTS

None of the 100 patients had pathological lymph-node metastasis (pLN) to level V. pLN to level IV was observed in two patients with tongue cancer in whom clinical lymph-node metastasis was preoperatively observed at level II.

CONCLUSIONS

Level V may be excluded in the neck dissection for patients with N1 oral cancers. Level IV dissection should be considered in the patient with tongue cancer and clinical lymph-node metastasis at level II.

Oncologic and functional outcomes of transoral CO2 laser cordectomy for early glottic cancer

OBJECTIVE

To investigate the oncological and functional outcomes of the patients treated with transoral CO2 laser cordectomy for early glottic cancer.

PATIENTS AND METHODS

Fifty-five consecutive patients who underwent CO2 laser cordectomy for early glottic cancer were retrospectively reviewed.

RESULTS

Overall survival, larynx preservation, and relapse free local control rates were 96%, 100%, and 91%, respectively. Five patients with local recurrences were salvaged with re-cordectomy and/or radiotherapy. In type I cordectomy, VHI-10 consistently improved during postoperative course and VHI-10 at postoperative 12months was significantly better than preoperative value (2.3 vs. 9.4, p=0.02). Perceptual grading, MPT, MFR and AC/DC also improved and were better than preoperative values. In type III cordectomy, shimmer at 12months after cordectomy was significantly better than preoperative value (14.7 vs. 9.3, p=0.007).

CONCLUSIONS

These results further support the rationale of CO2 cordectomy as initial and salvage surgery for early glottic cancer.

Results of free flap reconstruction for patients aged 80 years or older with head and neck cancer

OBJECTIVE

Free flap reconstruction in elderly patients is one of the most challenging surgeries in the treatment of head and neck cancers. The aim of this study was to examine the oncological and functional outcomes of free flap reconstruction for elderly patients with head and neck cancer.

METHODS

We retrospectively reviewed elderly patients who underwent free flap reconstruction for the treatment of head and neck cancers. All patients were 80 years or older. Clinicopathologic features, surgical procedures, oncological and functional outcomes were obtained from medical records.

RESULTS

Free flap reconstructions were performed in 13 patients (3 female, 10 male). The mean age was 82.6 ± 3.4 years (range: 80-91). The mean follow-up period was 23.3 months (range 4-41 months). The mean disease-free survival was 49 ± 6 months (range 4-60 months). All patients had been alive more than one year after surgery. Reconstruction was performed using free jejunum in 10 patients and radial forearm flap in 3 patients. Graft necrosis occurred in 2 patients. Other two patients experienced major postoperative medical complications.

CONCLUSION

Free flap reconstruction in well-selected older adults is safe and effective. Advanced age should not preclude consideration of free flap reconstruction in those patients.

A laryngeal closure technique for the treatment of patients with head and neck cancer

Background

In 2008, Kano developed a new laryngeal closure technique (Kano's method) for the treatment of severe aspiration. The aim of this study was to evaluate the safety and efficacy of this technique in patients with head and neck cancer.

Methods

Since June 2014 until March 2018, six patients underwent Kano's method for management of severe aspiration after the treatment of head and neck cancers. The anterior parts of the thyroid and the cricoid cartilages were excised widely. The glottis was closed by suturing bilateral vocal folds and reinforced by the sternohyoid muscle. A tracheostoma was created with skin flaps, subglottic mucosal flaps, and stumps of cricoid and trachea cartilages.

Results

No severe complications were observed after the surgery. Oral intake improved without developing aspiration.

Conclusions

Kano's method can provide satisfactory functional results with minimal invasion for treating severe aspiration after advanced surgery, chemotherapy, and/or chemoradiotherapy, in patients with head and neck cancer.

Level of Evidence

4

Clinical impact of a cytological screening system using cyclin D1 immunostaining and genomic analysis for the diagnosis of thyroid nodules

Background

Fine-needle aspiration (FNA) is the most reliable method for diagnosing thyroid nodules; however, some features such as atypia of undetermined significance or follicular lesion of undetermined significance can confound efforts to identify malignancies. Similar to BRAF, cyclin D1 may be a strong marker of cell proliferation.

Methods

One hundred two patients with thyroidal nodule were enrolled in this prospective study.

Expression of cyclin D1 in thyroid nodules was determined by immunohistochemistry using both surgical specimens and their cytological specimens. The identification of the optimal cut off points for the diagnosis of malignancy were evaluated using the receiver operating characteristic (ROC) curves and the assessment of the area under the ROC curve (AUC). The specificity, sensitivity, positive predictive value (PPV) of markers were evaluated from crosstabs based on cut off points and significance were calculated. We also analyzed genetic variants by target NGS for thyroid nodule samples.

Results

The positive predictive value (PPV) and median stain ratio (MSR) of cyclin D1 nuclear staining was determined in papillary thyroid carcinoma (PPV = 91.5%, MSR = 48.5%), follicular adenoma (PPV = 66.7%, MSR = 13.1%), and adenomatous goiter and inflammation controls (MSR = 3.4%). In FNA samples, a threshold of 46% of immunolabelled cells allows to discriminate malignant lesions from benign ones (P < 0.0001), with 81% sensitivity and 100% specificity. A 46% cutoff value for positive cyclin D1 immunostaining in thyroid cells demonstrated 81% sensitivity and 100% specificity. In surgical specimens, ROC curve analysis showed a 5.8% cyclin D1 immunostaining score predicted thyroid neoplasms at 94.4% sensitivity and 92.3% specificity (P = 0.003), while a 15.7% score predicted malignancy at 86.4% sensitivity and 80.5% specificity (P < 0.0001). Finally, three tested clinico-pathological variables (extra thyroidal extension, intraglandular metastasis, and lymph node metastasis) were significant predictors of cyclin D1 immunostaining (P < 0.001).

Conclusion

Our cytological cyclin D1 screening system provides a simple, accurate, and convenient diagnostic method in precision medicine enabling ready determination of personalized treatment strategies for patients by next generation sequencing using cytological sample.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5452-4) contains supplementary material, which is available to authorized users.

Clinical management for T1 and T2 external auditory canal cancer

OBJECTIVE

The purpose of this study was to clarify the impact of superficial parotidectomy and postoperative radiotherapy (PORT) for the surgical treatment of early stage squamous cell carcinoma (SCC) in external auditory canal (EAC).

MATERIALS AND METHODS

Thirty-seven patients with T1 (n = 14) or T2 (n = 19) SCC in EAC treated between 2000 and 2016 at Kobe University Hospital were enrolled in this study. Thirty-three patients were operated with sleeve resection or lateral temporal bone resection.

RESULTS

The 5-year overall survival and disease-specific survival rates were 95% and 100%, respectively. Surgical margin was positive in 4 patients, who were treated by PORT and have been alive without disease. Prophylactic superficial parotidectomy was simultaneously performed at the time of initial surgery in 15 patients, in whom no lymph node (LN) metastasis was observed. Among the other 22 patients, regional recurrence in parotid LN was observed in one patient, who was successfully salvaged by total parotidectomy. Potential parotid lymph node metastasis rates of T1 and T2 SCC in EAC was 0% (0/14) and 5% (1/19) respectively.

CONCLUSIONS

Complete resection without positive surgical margins is essential for the treatment of the patients with T1 and T2 ear cancers. Prophylactic superficial parotidectomy or neck dissection is not mandatory for T1 and T2 diseases, as long as precisely extent of disease is assessed preoperatively. PORT should be performed for the patients with positive surgical margins.

LEVELS OF EVIDENCE

4.

Impact of retropharyngeal lymph node dissection in the surgical treatment of hypopharyngeal cancer

OBJECTIVES

To evaluate the impact of retropharyngeal lymph node (RPLN) dissection in the surgical treatment of hypopharyngeal cancer.

METHODS

Between 2007 and 2016, 98 previously untreated patients with pathological diagnosed hypopharyngeal squamous cell carcinoma underwent total pharyngolaryngectomy and bilateral neck dissection at Kobe University Hospital. Bilateral dissection of RPLN was simultaneously performed in all patients. Pharynx was reconstructed with free jejunal transfer in 94 patients and primarily closed in 4 patients. Postoperative chemoradiotherapy was performed in patients with high risk factors including metastasis to RPLN, multiple lymph node metastasis, extranodal invasion, and/or positive/close surgical margins.

RESULTS

The median follow-up period was 25 months ranging from 1 to 105 months. RPLN adenopathy was preoperatively identified in 9 patients in FDG-positron emission tomography. All of them had pathologically diagnosed RPLN metastases, which had been controlled in all patients during the observation periods. Among the other 89 patients, 7 patients had RPLN metastasis. The 2-year overall survival rates of the patients with and without RPLN metastasis were 65.7% and 69.8% (P = .61), respectively.

CONCLUSIONS

In the present study, patients with RPLN metastasis showed equally favorable oncological outcome compared with patients without RPLN metastasis. At least, ipsilateral RPLN dissection should be considered in the surgical treatment of advanced hypopharyngeal cancer and multiple neck lymph node metastasis regardless of primary subsite.

Cardiac metastasis in a living patient with oral cancer

Cardiac metastasis from head and neck cancers are very rare. Metastases to heart are mostly diagnosed at autopsy, and seldom found while patients are alive. Patients with cardiac metastasis do not present with specific symptoms in the early stages, and diagnosis is often delayed until the disease has advanced significantly. Here, we report a 66-year-old lady who was diagnosed with cardiac metastasis 10 months after surgical resection of oral cancer. She died one month following the discovery of cardiac metastasis. Cardiac metastasis should be considered when unexplained and progressive decline of general health is observed, even in the absence of abnormalities on the electrocardiogram. Early diagnosis may be made by analyzing the chronological changes in the cardiac accumulation of fluorodeoxyglucose during positron emission tomography-computed tomography scan.

Role of intensive nutrition support and prophylactic percutaneous endoscopic gastrostomy during concomitant chemoradiotherapy for oropharyngeal cancer

BACKGROUND

Concomitant chemoradiotherapy (CCRT) produces severe mucositis and swallowing dysfunction, often resulting in malnutrition. Intensive nutrition support (INS) in addition to percutaneous endoscopic gastrostomy (PEG) is reported to decrease adverse effects during CCRT.

PATIENTS AND METHODS

Fifty-eight patients with oropharyngeal cancer treated by CDDP-based CCRT were retrospectively analyzed. Twenty-nine patients treated with INS in addition to PEG were classified as INS group, and other 29 patients treated with PEG but without INS were classified as control group.

RESULTS

INS in addition to PEG significantly increased calorie intake in the second half of CCRT and reduced adverse events including mucositis (p = 0.0019), leukopenia (p = 0.04), and renal function (p = 0.006). Moreover, 21 out of 29 patients had successfully administration of 200 mg/m2 or more of CDDP, while only 10 out of 29 patients had enough amount of CDDP in control group.

CONCLUSIONS

These results suggest that INS in addition to prophylactic PEG not only decreases adverse effects but also may potentially improve oncological outcome of the patients with oropharyngeal cancer treated by CCRT.

Impact of alcohol dehydrogenase-aldehyde dehydrogenase polymorphism on clinical outcome in patients with hypopharyngeal cancer

BACKGROUND

The purpose of this research was to investigate the association between alcohol dehydrogenase 1B (ADH1B) and aldehyde dehydrogenase 2 (ALDH2) polymorphisms and hypopharyngeal squamous cell carcinoma (SCC) survival.

METHODS

We genotyped ADH1B (rs1229984) and ALDH2 (rs671) single nucleotide polymorphisms (SNPs) in 85 Japanese male patients with hypopharyngeal SCC. The independent prognostic values of ADH1B-ALDH2 genotypes were analyzed by univariate and multivariate proportional hazard Cox regression, taking well-known clinical risk factors into account.

RESULTS

Heavy drinkers with ALDH2*2 allele resulted in significantly worse overall survival (OS; P = .028) and disease-free survival (DFS; P = .029) compared with other patients. Heavy drinkers with ALDH2*2 allele remained statistically significant in multivariate analysis for OS and DFS, indicating independent poor prognostic factor (hazard ratio [HR] 2.251; 95% confidence interval [CI] 1.018-4.975 and HR 2.261; 95% CI 1.021-5.006, respectively).

CONCLUSION

We conclude that heavy drinkers with the ALDH2*2 allele are associated with poor outcome in hypopharyngeal SCC.

Prognostic value of ALDH2 polymorphism for patients with oropharyngeal cancer in a Japanese population

Background

Half of Japanese possess a polymorphism of aldehyde dehydrogenase 2(ALDH2), while few white individuals possess this mutation. The purpose of this study was to investigate the possibility of ALDH2 polymorphism as a prognostic factor for oropharyngeal cancer (OPC) among Japanese population.

Methods

We analyzed 82 Japanese patients with OPC treated between 2006 and 2011. The median observation period was 50 months. P16-staining and ALDH2 polymorphisms were investigated. To examine the frequencies of second primary pharyngeal and esophageal cancers (SPPEC),37 Japanese patients with OPC treated at Tokyo University Hospital were included for statistical analysis.

Results

Statistically significant differences were noted in OS among sex, age, N classification, and p16 (p = 0.045, 0.024, 0.020, 0.007, respectively). In addition, OS and DSS rates of the patients with heterozygous ALDH2 tended to be worse than those of the patients with homozygous ALDH2 (p = 0.21, 0.086, respectively). Of note, OS and DSS of the patients with p16-negative OPC and heterozygous ALDH2 was significant poorer than those of the patients with p16-positive OPC (p = 0.002, 0.006, respectively), while there was no significant difference in OS and DSS between patients with p16-positive OPC and patients with p16-negative OPC and homozygous ALDH2.

Conclusions

ALDH2 polymorphism might be a promising prognostic factor for Japanese patients with p16-negative OPC.

Prognostic significance of surgical extranodal extension in head and neck squamous cell carcinoma patients

Background

Lymph node metastasis with extranodal extension represents one of the most important adverse prognostic factors for survival in patients with head and neck squamous cell carcinoma. We propose that extranodal extension occurs to differing extents. The aim of this study was to determine the prognostic significance of extranodal extension in patients with head and neck squamous cell carcinoma.

Methods

Two hundred and ninety-eight patients with head and neck squamous cell carcinoma who underwent surgical resection and neck dissection were included. Cervical lymph nodes were classified into four categories: (i) pathological N negative, (ii) extranodal extension negative, (iii) non-surgical extranodal extension and (iv) surgical extranodal extension.

Results

Lymph node metastases were detected in 67.1% of laryngeal/hypopharyngeal cancer patients and 52.7% of oral cancer patients. The 3-year disease-specific survival rates for patients in the pathological N negative, extranodal extension negative, non-surgical extranodal extension and surgical extranodal extension groups were 90.9%, 79.6%, 63.8% and 48.3%, respectively. In laryngeal/hypopharyngeal cancer patients, surgical extranodal extension was associated with a significantly poorer disease-specific survival than a pathological N negative, extranodal extension negative or non-surgical extranodal extension status. In oral cancer patients, no significant differences were observed between the non-surgical and surgical extranodal extension groups. However, non-surgical extranodal extension was associated with a poorer disease-specific survival than a pathological N negative or extranodal extension negative status.

Conclusions

Surgical extranodal extension was a poor prognostic factor in patients with head and neck squamous cell carcinoma. The prognostic significance of surgical extranodal extension differed between laryngeal/hypopharyngeal and oral cancer patients. The clinical significance of surgical extranodal extension was much greater for patients with laryngeal/hypopharyngeal cancer than oral cancer.

Complications in Salvage Surgery for Nasal and Paranasal Malignant Tumors Involving the Skull Base

Objective  Nasal and paranasal malignant tumors invading the skull base are rare and poorly studied. We evaluated postoperative complications in patients undergoing salvage surgery for such tumors. Design  Retrospective study. Setting  Kobe University Hospital. Participants  Among 48 patients who underwent surgery for tumors involving the skull base between 1993 and 2015, 21 patients had squamous cell carcinoma, 13 had olfactory neuroblastoma, 5 had adenocarcinoma, 2 had sarcoma, 2 had adenoid cystic carcinoma, and 1 each had malignant melanoma, poorly differentiated carcinoma, undifferentiated carcinoma, myoepithelial carcinoma, and malignant peripheral nerve sheath tumor. Prior to skull base surgery, radiotherapy, chemoradiotherapy (CRT), particle radiotherapy, chemotherapy, or surgery were applied in 3, 15, 4, 5, and 3 patients, respectively. Main Outcome Measures  Main outcome measures were postoperative complications in patients who underwent skull base surgery after concomitant CRT and/or particle therapy. Results  Major postoperative complications were observed in 14 surgical procedures (29%; 2 patients with cerebral herniation, 3 with cerebrospinal fluid leakages, 3 with meningitis, 1 with hydrocephalus, 6 with epidural abscesses, 2 with local infections, and 2 with partial flap necrosis). Four patients developed ≥2 complications. One patient died of postoperative lung infarction. Three (16.7%) of 18 patients without prior treatment and 9 (50%) of 18 patients who underwent preoperative radiotherapy/CRT had severe postoperative complications. Two (50%) of four patients treated with particle radiotherapy had postoperative complications. Conclusions  CRT or particle radiotherapy were significantly associated with a high risk of severe postoperative complications after skull base surgery. Meticulous care should be taken in patients treated with radiotherapy/particle therapy prior to skull base surgery.

Significance of delayed primary excision in localized nonmetastatic adult head and neck rhabdomyosarcoma

Adult rhabdomyosarcoma (RMS) is a highly aggressive tumor. Multidisciplinary treatment is important. However, the role of surgery is controversial. The purpose of this study was to reveal the role of a delayed primary excision (DPE) after induction chemotherapy (IC) in localized nonmetastatic adult head and neck RMS. We retrospectively reviewed 24 adult head and neck RMS. Treatment was classified into the following two groups: the DPE group, who received IC followed by surgery, postoperative radiotherapy, and adjuvant chemotherapy (17 patients); the chemoradiotherapy (CRT) group, who received IC followed by chemoradiotherapy (seven patients). We analyzed the efficacy of IC, local control rate (LCR), and overall survival (OS). In the DPE group, 10 patients (59%) underwent complete surgical resection. In the evaluation of the surgical specimens, 14 patients (82%) had residual viable tumors after IC. The response to IC was significantly associated with the 3‐year LCR (CR/PR vs. SD/PD: 100% vs. 33%, P = 0.0014). In patients with good response to chemotherapy, the DPE group had a significantly better 3‐year LCR compared with that of the CRT group (DPE group vs. CRT group, 100% vs. 44%, P = 0.018). However, the treatment modalities were not associated with OS (DPE group vs. CRT group, 65% vs. 57%: P = 0.98). The recurrence patterns differed according to treatments, and distant metastases were more frequent in the DPE group. DPE may impact local control of localized nonmetastatic adult head and neck RMS. Poor response to IC is a risk factor for local recurrence.