Maximum standardized uptake value in 11C-methionine positron emission tomography may predict the prognosis of patients with oral squamous cell carcinoma.

The present study aimed to elucidate the correlation between the uptake of 11C-methionine (MET) by a primary tumor and the survival of patients with oral squamous cell carcinoma (OSCC). This study enrolled 31 patients who underwent radical surgery for OSCC. The patients underwent pretreatment MET-positron emission tomography (PET) scanning. We analyzed correlations between the maximum standardized uptake value (SUVmax) of MET-PET in a primary tumor and the clinicopathological features. Further, we compared overall survival (OS), disease-specific survival (DSS), and loco-regional recurrence (LRR) rates between the two groups according to SUVmax of MET-PET. SUVmax of MET-PET in a primary tumor was higher in patients with advanced T-classification and advanced clinical stage, with significant differences (P = 0.001 and P = 0.016, respectively). The patients with SUVmax of MET-PET ≥ 4.4 showed significantly lower DSS rates and higher LRR rates than those with SUVmax of < 4.4 (P = 0.015 and P = 0.016, respectively). SUVmax of MET-PET and OS rates showed no significant correlation (P = 0.073). The present study revealed that SUVmax of MET-PET may predict clinical outcomes and prognosis in patients with OSCC who underwent radical surgery.

Clinicopathological analysis of 134 patients with squamous cell carcinoma of the mandibular gingiva.

Objective: The accurate assessment of the involvement of mandibular gingival squamous cell carcinoma (SCC) is essential for determining the extent of resection and is also useful for predicting lymph node metastasis and prognosis. The purpose of this study was to investigate the factors for predicting the prognosis. Study design: We reviewed 134 patients with mandibular gingival SCC treated between 2008 and 2017. The clinical findings, TN stage, relationship between radiographical type and histological pattern, and factors affecting the survival rate were investigated. Results: The moth-eaten radiographic type was significantly associated with histologically infiltrative pattern. For all 134 cases, the 5-year OS was 89.5 %, and 5-year DSS was 93.9 %. The 5-year DSS was 95.0 % for cN0 and/or pN0 cases and 90.3 % for pN (+) cases, with a significant difference. The significant risk factors for lymph node metastasis were teeth extractions by previous physicians and moth-eaten radiographic type. Conclusion: The risk factor for poor prognosis was lymph node metastasis. In addition, teeth extractions by previous physicians and moth-eaten radiographic type were the risk factors for lymph node metastasis. It is recommended that these cases be treated considering the possibility of cervical lymph node metastasis.

The Efficacy of Immunotherapy and Clinical Utility of Comprehensive Genomic Profiling in Adenoid Cystic Carcinoma of Head and Neck.

Background and Objectives: Adenoid cystic carcinoma (ACC) of the head and neck is generally slow-growing but has a high potential for local recurrence and metastasis to distant organs. There is currently no standard pharmacological treatment for recurrent/metastatic (R/M) ACC, and there are cases in which immune checkpoint inhibitors (ICIs) are administered for ACC according to head and neck squamous cell carcinoma (HNSCC). However, the efficacy of ICIs for ACC remains unclear, and the predictive biomarkers need to be elucidated. Materials and Methods: The Center for Cancer Genomics and Advanced Therapeutics (C-CAT) database enabled the retrospective but nationwide analysis of 263 cases of ACC of the head and neck. Then, we examined and reported four cases of ACC that received ICIs and comprehensive genomic profiling (CGP) in our institution. Results: The C-CAT database revealed that 59 cases out of 263 received ICIs, and the best response was 8% of objective response rate (ORR) and 53% of disease control rate (DCR) (complete response, CR 3%, partial response, PR 5%, stable disease, SD 44%, progressive disease, PD 19%, not evaluated, NE 29%). The tumor mutational burden (TMB) in ACC was lower overall compared to HNSCC and could not be useful in predicting the efficacy of ICIs. Some cases with MYB structural variants showed the response to ICIs in the C-CAT database. A patient with MYB fusion/rearrangement variants in our institution showed long-term stable disease. Conclusions: ICI therapy is a potential treatment option, and the MYB structural variant might be a candidate for predictive biomarkers for immunotherapy in patients with R/M ACC.

Free-flap volume correlates with body mass index in patients with tongue squamous cell carcinoma.

Objectives: This study aimed to investigate the relationship between postoperative reconstructed tongue flap volume (RTFV) and body mass index (BMI) and identify factors affecting the flap volume in patients with tongue squamous cell carcinoma. Methods: Thirty-two patients were evaluated for RTFV from computed tomography images and BMI. The first and second evaluations were done at 6 months and 1.5 years after surgery respectively. RTFV rate changes and BMI differences from the first and second evaluations were calculated. The correlation between RTFV rate change and BMI difference was assessed using Spearman's rank correlation coefficient. Multiple regression analysis evaluated the relationship between the flap volume rate change and age, sex, flap type, and BMI difference to identify influencing factors. Results: The flap volume rate change and BMI difference correlated significantly (r = .594, p < .05). BMI difference and flap type were independent factors that affected reconstructed flap volume rate change in multiple regression analysis (p < .05). Conclusion: The flap volume of patients with tongue squamous cell carcinoma correlates with the BMI change in the chronic phase. Patients after tongue reconstruction need to be well nourished to maintain BMI and thus postoperative tongue volume to maintain the quality of life. Level of Evidence: Level 3.

Invasion of the bucco-mandibular space by oral squamous cell carcinoma: histopathological analysis of invasion pattern.

Background: This study aimed to determine the patterns of invasion of oral squamous cell carcinoma (OSCC) into the bucco-mandibular space (BMS) using detailed histopathological analysis and to assess clinical outcomes. Methods: Patients with OSCC who underwent segmental mandibulectomy or hemi-mandibulectomy combined with resection of the BMS between 2012 and 2021 were included. The invasions of the BMS were classified into three patterns. Pattern A was defined as a horizontal invasion, Pattern B as a vertical invasion, and Pattern C as an expansive invasion. Results: In total, 109 patients were reviewed. Of these 109 patients, the primary tumor affected the lower gingiva in 78 patients, the buccal mucosa in 18 patients, and was a primary intraosseous carcinoma of the mandible in 13 patients. Invasion of the BMS was significantly associated with a higher pathological T stage, positive/close margins, and lower disease-free survival (DFS) rates. The DFS rates were 86.7% and 66.0% in the BMS non-invasion and invasion groups, respectively. The DFS rates for each type of invasion were 82.1% for Pattern A, 67.4% for Pattern B, and 48.0% for Pattern C (P=0.277). Conclusion: Patients with BMS invasion have a poorer prognosis than those without invasion of the BMS. Therefore, adjuvant therapy is necessary, especially in Patterns B and C. Evaluation of preoperative BMS invasion patterns is important for predicting the prognosis of OSCC.

Buccinator muscle invasion is a risk factor for cervical lymph node metastasis in squamous cell carcinoma of the buccal mucosa: A retrospective study.

The present study aimed to determine the risk factors associated with cervical lymph node metastasis (CLNM) in patients with buccal mucosa squamous cell carcinoma (BMSCC). This retrospective study included patients with primary BMSCC who underwent surgery at the Department of Oral and Maxillofacial Surgical Oncology of Tokyo Medical and Dental University (Tokyo, Japan) between January 2008 and December 2017. The following data were collected and analyzed: Sex, age, primary lesion subsite, tumor/node/metastasis stage, clinical growth patterns, tumor differentiation, lymphovascular and perineural invasion, mode of invasion, pathological depth of invasion, extent of tumor invasion, and clinical outcome of patients with BMSCC. Multivariate analysis was performed to identify the possible risk factors for CLNM. A total of 75 patients were included in the present study, among whom 30 (40%) were found to have histological CLNM. Of the 33 patients with buccinator muscle infiltration by the tumor, 24 (72.7%) had CLNM. Multiple logistic regression analysis revealed that buccinator muscle invasion was the most significant predictive risk factor for CLNM in BMSCC. The present study found that tumor invasion of the buccinator muscle was the most significant predictive risk factor for CLNM in BMSCC. Therefore, elective neck dissection should be performed if buccinator muscle invasion is identified in patients with BMSCC.

A rare case of solitary intraoral superficial angiomyxoma arising in the soft palate.

Superficial angiomyxomas are myxoid mesenchymal tumors, and intraoral superficial angiomyxoma is extremely rare. This paper reports a novel case of a 41-year-old Japanese male patient with a 32 × 22 mm superficial angiomyxoma in the right soft palate. Tumor resection was performed and a polyglycolic acid sheet was attached. Over a 28-month follow-up, there was no evidence of disease recurrence. This paper also reviewed 11 cases of intraoral superficial angiomyxomas reported in previous literature. The condition was more common among middle-aged men. Surgical resection was the most common treatment, and local recurrence was observed in only one case.

Retrograde Migration of an Au-198 Grain to the Submandibular Gland Post Brachytherapy Treatment of Floor of Mouth Cancer.

At our institution, radiation oncologists routinely treat early-stage oral cancer with low-dose-rate brachytherapy (LDR-BRT) using Au-198 grains. In this report, we show a unique case of a patient with a gold grain located within the submandibular gland, found incidentally during follow-up after LDR-BRT for floor of mouth cancer. One month after the implant, he showed sialadenitis-like symptoms, but the pain resolved two months later. All the grains were detected around the anterior sublingual area by computed tomography (CT) four months after the implant. Unexpectedly, 11 months after the implant, CT revealed that a grain was located in an intraglandular site of the submandibular gland. This finding clearly demonstrates that the grain entered Wharton's duct and retrogradely migrated to the submandibular gland through the duct. As a mechanism of the calculus formation within Wharton's duct, retrograde migration of foreign bodies to the inside of the duct has been proposed. Our incidental finding after LDR-BRT highlights the need for monitoring post-LDR-BRT using Au-198 grains for the treatment of floor of mouth cancer and sheds additional light on retrograde theory within Wharton's duct.

High expression of Sam68 contributes to metastasis by regulating vimentin expression and a motile phenotype in oral squamous cell carcinoma.

The present study aimed to investigate the clinical and biological significance of Src­associated in mitosis 68 kDa (Sam68) in oral squamous cell carcinoma (OSCC). Immunohistochemical analysis was performed on tissue samples obtained from 77 patients with OSCC. Univariate analysis revealed that the high expression of Sam68 was significantly correlated with advanced pathological T stage (P=0.01), positive lymphovascular invasion (P=0.01), and pathological cervical lymph node metastasis (P<0.01). Moreover, multivariate analysis demonstrated that the high expression of Sam68 was an independent predictive factor for cervical lymph node metastasis (odds ratio, 4.39; 95% confidence interval, 1.49­14.23; P<0.01). These results indicated that high Sam68 expression contributed to tumor progression, especially cervical lymph node metastasis, in OSCC. mRNA sequencing was also performed to assess the changes in the transcriptome between OSCC cells with Sam68 knockdown and control cells with the aim of elucidating the biological roles of Sam68. Gene Ontology enrichment analysis revealed that downregulated differentially expressed genes (DEGs) were concentrated in some biological processes related to epithelial­mesenchymal transition. Among these DEGs, it was established that vimentin was particularly downregulated in these cells. It was also confirmed that Sam68 knockdown reduced the motility of OSCC cells. Furthermore, the immunohistochemical study of vimentin identified the association between vimentin expression and Sam68 expression as well as cervical lymph node metastasis. In conclusion, the present study suggested that the high expression of Sam68 may contribute to metastasis by regulating vimentin expression and a motile mesenchymal phenotype in OSCC.

Comprehensive Genomic Profiling Reveals Clinical Associations in Response to Immune Therapy in Head and Neck Cancer.

Comprehensive genomic profiling (CGP) provides information regarding cancer-related genetic aberrations. However, its clinical utility in recurrent/metastatic head and neck cancer (R/M HNC) remains unknown. Additionally, predictive biomarkers for immune checkpoint inhibitors (ICIs) should be fully elucidated because of their low response rate. Here, we analyzed the clinical utility of CGP and identified predictive biomarkers that respond to ICIs in R/M HNC. We evaluated over 1100 cases of HNC using the nationwide genetic clinical database established by the Center for Cancer Genomics and Advanced Therapeutics (C-CAT) and 54 cases in an institution-based study. The C-CAT database revealed that 23% of the cases were candidates for clinical trials, and 5% received biomarker-matched therapy, including NTRK fusion. Our institution-based study showed that 9% of SCC cases and 25% of salivary gland cancer cases received targeted agents. In SCC cases, the tumor mutational burden (TMB) high (≥10 Mut/Mb) group showed long-term survival (>2 years) in response to ICI therapy, whereas the PD-L1 combined positive score showed no significant difference in progression-free survival. In multivariate analysis, CCND1 amplification was associated with a lower response to ICIs. Our results indicate that CGP may be useful in identifying prognostic biomarkers for immunotherapy in patients with HNC.

Adenovirus infection controls processing bodies to stabilize AU-rich element-containing mRNA.

In the adenovirus-infected cells, virus mRNAs are selectively exported to the cytoplasm by virus early gene products to facilitate virus replication. We previously showed AU-rich elements (AREs) containing mRNAs are exported to the cytoplasm and stabilized in infected cells. Here, we analyzed ribonucleoprotein (RNP) granules in the cytoplasm that are involved in mRNA degradation to elucidate the mechanism of ARE-mRNA stabilization in adenovirus infected cells. Our findings showed that processing bodies (PBs) aggregate, then almost all PBs are translocated to aggresomes formed by adenoviral gene products during the late phase of infection. Furthermore, E4orf3 was required for the PBs translocation, and the same domains of E4orf3-mutants required to change the form of promyelocytic leukemia bodies were also needed for PBs translocation. Luciferase activity showed that these domains were critical for miRNA- and ARE-mediated mRNA decay. These findings suggest that adenovirus changes the behavior of PBs to prevent ARE-mRNA downregulation.

Clinical manifestations of diffuse large B-cell lymphoma that exhibits initial symptoms in the maxilla and mandible: a single-center retrospective study.

BACKGROUND: Diffuse large B-cell lymphoma (DLBCL) is the most common type of lymphatic tumor; however, extranodal DLBCLs that exhibit initial symptoms in the maxilla and mandible are rare. Moreover, DLBCL is clinically classified as a moderate to highly malignant lymphatic tumor that can progress rapidly; therefore, early diagnosis is crucial. However, diagnosis is difficult as the disease causes a diverse range of clinical symptoms with no characteristic imaging findings. We conducted a clinical investigation to clarify the clinical characteristics of DLBCL that exhibits initial manifestation in the maxilla and mandible. METHODS: Of the 2748 patients with malignant tumors of the oral and maxillofacial region examined at our hospital during a period of 11 years between January 2006 and December 2016, 27 primary cases diagnosed with DLBCL based on the chief complaint of symptoms in the gingiva and bone of the maxilla and mandible were enrolled in this study. Evaluations were based on sex, age, whether treatment was provided by a previous physician, symptoms, duration of disease until treatment was sought, clinical diagnosis, laboratory findings, and imaging results. RESULTS: There were 15 cases that involved the maxilla and 12 that involved the mandible. The median duration of disease until treatment was sought was 60 d (3-450 d). All cases exhibited a tumor or a mass, and hypoesthesia of the chin was confirmed in eight cases wherein the mandible was involved. The clinical stages were stage I in eight cases, stage II in ten cases, and stage IV in nine cases. Serum lactate dehydrogenase (LDH) levels were elevated in 13 of 22 patients. The overall survival rate was 63%. CONCLUSIONS: Symptoms associated with nontender swelling and numbness of the lip or chin in the absence of other findings such as dental infections should raise suspicions about DLBCL. Patients should be provided appropriate imaging and accurate biopsy assessments to improve prognosis.

Left supraclavicular (Virchow's) node metastasis detected before primary infradiaphragmatic tumor: a case series.

BACKGROUND: Metastasis of infradiaphragmatic tumors to the left supraclavicular lymph node is reported to be rare. When metastasis is detected in the left supraclavicular node in patients with head and neck carcinoma, locating the primary cancer remains a difficult and time-consuming challenge despite the dramatic development of screening technologies and treatment methods. CASE PRESENTATION: We report three cases of malignant infradiaphragmatic tumor diagnosed following an initial finding of left supraclavicular node metastasis after surgery for tongue squamous cell carcinoma (follow-up period, range 18-62 months). In these cases, adenocarcinoma was diagnosed based on left supraclavicular node biopsies, and a second primary tumor was found, in a 78-year-old Japanese woman with a diagnosis of cholangiocarcinoma, a 64-year-old Japanese man with a diagnosis of bladder carcinoma, and a 61-year-old Japanese man with a diagnosis of prostate carcinoma. In the cholangiocarcinoma case, carbohydrate antigen 19-9 and alpha-fetoprotein levels helped to diagnose cholangiocarcinoma. Palliative care only was given, with survival for 11 months after diagnosis of lymph node metastasis. In the bladder carcinoma case, pathological analysis of fine-needle aspiration biopsy specimen of the metastatic cervical lymph node showed atypical cells with slight squamous differentiation. Hematoxylin-eosin staining of the bladder lesion did not identify a clear glandular or squamous component, and we could not make a definitive diagnosis of whether the lesion was poorly differentiated squamous cell carcinoma, adenocarcinoma, or high-grade urothelial carcinoma. GATA3 staining aided in the diagnosis of urothelial bladder cancer with left supraclavicular node metastasis. He survived for 2 months after diagnosis of left supraclavicular lymph node metastasis. In the prostate carcinoma case, 18F-fluorodeoxyglucose uptake was weak. Prostate-specific antigen levels and magnetic resonance imaging findings aided the diagnostic process. This patient underwent bilateral orchiectomy and adjuvant hormonal therapy and survived for 47 months after diagnosis of left supraclavicular node metastasis. CONCLUSIONS: Pathological diagnosis on the basis of immunohistochemistry and specific diagnosis methods such as radiological and serological assessments are important for providing rapid diagnosis and appropriate treatment.

Epithelial-Myoepithelial Carcinoma of the Minor Salivary Glands: Case Series with Comprehensive Review.

Epithelial-myoepithelial carcinoma (EMC) is a rare salivary gland tumor that is histologically characterized by biphasic tubular structures composed of inner ductal and outer clear myoepithelial cells, which is especially uncommon in the minor salivary glands (MSG). Because of its histologic variety, complexity, and heterogeneity, it is sometimes challenging to make the accurate diagnosis. Here, we report a literature review of EMC of the MSGs with our experience of two cases. Incisional biopsy was suggestive of pleomorphic adenoma in Case 1 and pleomorphic adenoma or a low-grade salivary gland carcinoma in Case 2. Both cases were performed intraoral tumor resection, and they have good postoperative courses and are alive with no evidence of local recurrence or metastasis at 31 and 16 months, respectively. Considering that the anatomy, structure, and size of salivary glands are quite different from MSGs, it might be difficult to predict EMCs of the MSG similarly to EMCs of the major salivary glands. This comprehensive review also reports the features of EMC of the MSG cases and the trends of diagnosis and discusses treatment strategy.

Multicenter retrospective analysis of clinicopathological features and prognosis of oral tongue squamous cell carcinoma in adolescent and young adult patients.

ABSTRACT: The aim of this study is to report the differences in clinicopathological features of oral tongue squamous cell carcinoma (OTSCC) and survival between adolescent and young adult (AYA) patients and elderly patients and to find the prognosticators. The medical records of 101 AYA patients and 175 control patients with OTSCC who underwent surgery were reviewed. Variables related to prognosis and their clinicopathological associations were analyzed. The 5-year overall survival (5y-OS) rates of AYA and control patients with stage I and II OTSCC were 94.4% and 89.6% (P = .353), respectively, and their 5-year disease-free survival (5y-DFS) rates were 82.0% and 76.6%, respectively (P = .476). The 5y-OS rates of patients with stages III and IV OTSCC were 83.3% and 66.7% (P = .333), respectively, and their 5y-DFS rates were 75.0% and 57.1% (P = .335), respectively. Logistic regression analysis revealed that there was no significant clinicopathological difference in AYA and control group. Furthermore, there was no significant difference in 5y-OS rates between patients who underwent elective neck dissection (END) and those who underwent therapeutic neck dissection (TND) in both group (P = 0.717 and 0.688). Overall, the present study revealed the clinicopathological features and prognosis of OTSCC were similar in AYA patients and elderly patients. Moreover, as there was no significant difference in OS between patients who underwent END and those who underwent TND in AYA and control groups, our results suggest that the indication for END in AYA patients with clinical N0 OTSCC is similar to that for elderly patients.

Prognostic impact of lingual lymph node metastasis in patients with squamous cell carcinoma of the tongue: a retrospective study.

Squamous cell carcinoma (SCC) of the tongue rarely metastasizes to the lingual lymph nodes (LLNs), which are inconstant nodes and often situated outside the areas of basic tongue tumor surgery. The current study evaluated the clinicopathological features and prognostic impact of LLN metastasis (LLNM), compared to that of cervical lymph node metastasis, in patients with tongue SCC. A total of 608 patients underwent radical surgery for tongue SCC at our department between January 2001 and December 2016. During neck dissection, we scrutinized and resected lateral LLNs, when present. Of the 128 patients with lymph node metastasis, 107 had cervical lymph node metastasis and 21 had both cervical lymph node metastasis and LLNM. Univariate analysis demonstrated that LLNM was significantly associated with the adverse features of cervical lymph node metastasis. The 5-year disease-specific survival (5y-DSS) was significantly lower in patients with LLNMs than in those without LLNMs (49.0% vs. 88.4%, P < 0.01). Moreover, Cox proportional hazards model analyses revealed that cervical lymph node metastasis at level IV or V and LLNM were independent prognostic factors for 5y-DSS. LLNM has a strong negative impact on survival in patients with tongue SCC. An advanced status of cervical lymph node metastasis may predict LLNM.

MRI before biopsy correlates with depth of invasion corrected for shrinkage rate of the histopathological specimen in tongue carcinoma.

The purpose of this study was to evaluate which radiological depth of invasion (r-DOI) measurement is the most concordant to clinical DOI (c-DOI) derived from correction for the shrinkage rate of the histopathological specimens. We retrospectively reviewed 128 patients with tongue carcinoma who had undergone glossectomy between 2006 and 2019. At first, the width shrinkage rate during formalin fixation and preparation process of histopathological specimens was evaluated. From the shrinking rates, a formula to calculate c-DOI from pathological DOI (p-DOI) was developed. The correlation between c-DOI and r-DOI was evaluated. The specimen shrinkage rate during the histopathological specimen preparation process was 10.3%. Based on that, we yielded the correct formula for c-DOI based on p-DOI and preparation shrinkage rate: c-DOI = p-DOI × 100/89.7. The regression equations for the association of c-DOI with r-DOI measured by ultrasound (n = 128), MRI before biopsy (n = 18), and MRI after biopsy (n = 110) were y = 1.12 * x + 0.21, y = 0.89 * x - 0.26, and y = 0.52 * x + 2.63, respectively, while the coefficients of determination were 0.664, 0.891, and 0.422, respectively. In conclusion, r-DOI using MRI before biopsy most strongly correlated with c-DOI.

Metastatic tumors in the oral region: a retrospective chart review of clinical characteristics and prognosis.

OBJECTIVE: The study aimed to evaluate the clinical characteristics and outcomes of patients with metastatic tumors in the oral region. STUDY DESIGN: We conducted a retrospective study of 14 patients (11 men and 3 women; median age, 70.5 years) with metastatic tumors in the oral region diagnosed between 2005 and 2018. RESULTS: The primary tumors were located in the lung (n = 7), kidney (n = 3), renal pelvis (n = 1), thyroid (n = 1), stomach (n = 1), and bladder (n = 1). The most common histologic type of the tumor was adenocarcinoma (n = 6). The metastatic sites were the mandible (n = 7), tongue (n = 4), upper gingiva (n = 2), and maxilla (n = 1). In 6 patients, metastatic tumors were found in the oral region before the primary tumors were detected. The primary tumors were detected by positron emission tomography/computed tomography in 5 patients and by computed tomography alone in one patient. Seven patients received treatment for metastatic tumors in the oral region. The overall 1- and 5-year survival rates were 35.7% and 10.7%, respectively. CONCLUSIONS: It is important to detect metastatic tumors in the oral region and primary tumors as early as possible. Radical or palliative treatment should be performed if possible, considering the condition of the primary tumor and its metastasis to other organs.

Mandibular Reconstruction with Scapular Systems: A Single-Center Case Series Involving 208 Flaps.

BACKGROUND: The scapular flap is the most versatile composite flap used for mandibular reconstruction. The purpose of this study was to review and summarize findings of cases of mandibular reconstruction with a scapular flap and describe associated outcomes and complications. METHODS: A total of 208 microvascular scapular free flaps were performed for mandibular reconstruction in a total of 205 patients from 2003 to 2018. This study involved a retrospective review of all eligible patients' medical records. RESULTS: There were seven cases (3.4 percent) of microvascular thrombosis. Postoperative bone union was achieved by 201 patients, except for five with total flap necrosis and two with partial flap necrosis. There were four cases (1.9 percent) of mandibular condyle dislocation. Two major types of complications were observed at the donor site, including four cases of infection and six cases of scapular body fracture. Postoperative denture prosthesis was introduced to 97 patients (47.3 percent). Implant treatment was performed in 10 patients (4.9 percent). Functional and aesthetic outcomes were good to excellent. CONCLUSIONS: The scapular composite free flap for mandibular reconstruction was associated with favorable outcomes and demonstrated satisfactory results. Although scapular bone fracture is rare, patients who have undergone mandibular reconstruction using a scapular flap should be monitored for its presence. . CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Comparison of Clinicopathological Characteristics Between the Anterior and Posterior Type of Squamous Cell Carcinoma of the Floor of the Mouth: The Anterior Type Is a Risk Factor for Multiple Primary Cancer.

BACKGROUND: Floor of the mouth (FOM) squamous cell carcinoma (SCC) accounts for approximately 10% of all oral SCCs. FOM SCC can be classified into the anterior and posterior types according to their site of origin, but few studies have compared these types. This study sought to clarify differences in clinicopathological characteristics between these two types. METHODS: A total of 1,220 patients with oral SCC were treated at our department from January 2001 to December 2015. Among these patients, 62 had FOM SCC. The FOM SCCs were classified into two groups: the anterior type and the posterior type. The anterior and posterior types were defined by the boundary connecting the spaces between the canine and the first premolar bilaterally. We retrospectively compared the sex, age, smoking and drinking history, clinical stage, treatment, histopathological diagnosis, multiple primary cancers, and outcomes of the two groups. RESULTS: Among the 62 patients, 32 had the anterior type, while 30 had the posterior type. The anterior type was found more significantly in men (p = 0.01) and individuals with a smoking history than the posterior type (p = 0.04). pN2-3 cervical lymph node metastasis was significantly more common in the anterior type than in the posterior type (p = 0.01). The median depth of invasion in the anterior type was 4 mm. Multivariate analysis showed that the anterior type was an independent risk factor for multiple primary cancer development in FOM SCC (p = 0.02). The cumulative 10-year disease-specific survival rates of the anterior and posterior types were 92.8 and 95.0%, respectively, while the overall survival rates were 65.4 and 95.0%, respectively. In the anterior type FOM SCC, a lower overall survival rate was associated with multiple primary cancers and smoking-related diseases. CONCLUSION: Smoking cessation and adequate systemic screening for multiple primary cancers are needed to improve the prognosis of FOM SCC, particularly the anterior type.