[A Case of Severe Skin Disorder during Pembrolizumab Treatment for Recurrent Maxillary Gingival Carcinoma].

Immune checkpoint inhibitors are known to produce immune-related adverse events(irAE)that require medical management. Herein, we report a case of a patient treated with pembrolizumab who experienced a Grade 3 interrupted skin disorder. The patient is a 67-year-old female diagnosed with right maxillary gingival squamous cell carcinoma(cT4aN0M0, Stage ⅣA)and underwent partial right maxillectomy, right extended supra-omohyoid neck dissection, and maxillary reconstruction using a forearm flap. Six months postoperatively, late lymph node metastases with extracapsular spread was found in the right buccal lymph node and the left neck, and the patient underwent right buccal lymphadenectomy and left modified radical neck dissection. After postoperative combined chemoradiotherapy(cisplatin plus IMRT)followed by 13 courses of cetuximab plus paclitaxel, a recurrent lesion was found in the right buccal region. After 8 courses of pembrolizumab, a skin rash appeared on the forearm, chest, and back, which was diagnosed as Grade 3 irAE, requiring hospitalization. The patient was re-instituted after waiting for improvement of the skin disorder. The pembrolizumab at 75% reduction dose was re-administrated, and the patient has been followed up so far.

[A Case of Reconstruction of the Osteoradionecrosis of the Jaw Using the Patient-Specific Custom-Made Cutting Guide and Mandibular Reconstruction Plate].

Multidisciplinary treatment, combining ablative surgery and reconstruction, radiotherapy, and chemotherapy, is used to treat advanced oral cancers. In this study, we report a case of extensive osteoradionecrosis of the mandible following multidisciplinary treatment for tongue cancer, in which a computer-assisted, patient-specific custom-made cutting guide and reconstruction plate(TruMatch® )were used to improve the patient's facial morphology and oral-maxillofacial functioning. A 70-year-old man received multidisciplinary treatment for squamous cell carcinoma of the left side of the tongue (cT3N2bM0, cStage ⅣA)at a previous hospital. Seven years postoperatively, bilateral osteoradionecrosis of the mandible developed, and the patient was referred to our department for further treatment. Since the lesions were extensive, we planned reconstructive surgery using the TruMatch® system in collaboration with the plastic surgery department of our hospital. Surgery was performed precisely and accurately according to the preoperative simulation. Postoperatively, the patient's recovery was uneventful. The TruMatch® system enables us to achieve good morphological and comprehensive functional oral-maxillofacial reconstruction.

[Effect of the Hyoid Bone Suspension Technique on the Preservation of Swallowing Function after Total Glossectomy and Pectoralis Major Musculocutaneous Flap Reconstruction for Locally Advanced Tongue Cancer].

Dysphagia is a major postoperative complication in patients with locally advanced oral cancer. In this case report, we describe the effect of the hyoid bone suspension technique on the preservation of swallowing function after total glossectomy and pectoralis major musculocutaneous flap reconstruction for locally advanced tongue cancer. Case: A 72-year-old Japanese male was diagnosed with advanced squamous cell carcinoma on the left side of his tongue(cT4aN2cM0, cStage ⅣA). Under general anesthesia, the patient underwent a tracheotomy, bilateral modified radical neck dissection type Ⅲ, total glossectomy, and reconstruction with a left pectoralis major musculocutaneous flap(PMMC flap). Intraoperatively, the PMMC flap was designed to have a heart shape of 11×6 cm and was elevated. Subsequently, holes were made at the lower edge of the mandible, and the hyoid bone was suspended and fixed to the mandibular border using 2-0 nylon sutures. The postoperative course was uneventful; the flap was completely engrafted and was in good condition. The hyoid bone suspension technique can reproduce the pharyngeal phase of swallowing, and the palatal augmentation prosthesis helps to improve food mass feeding and preserve the swallowing function.

[Surgical Treatment of Maxillary Gingival Carcinoma with Mental Retardation-A Case Report].

Many patients with mental retardation have a limited awareness of abnormalities in the oral cavity, making early detection of oral cancer difficult. Moreover, during examination and treatment, these patients may not understand well-intentioned verbal explanations and may express their anxiety through nonverbal communication. Herein we discuss a case in which favorable results were obtained when surgical treatment was performed on a maxillary gingival carcinoma patient with mental retardation. The patient was a 61-year-old man who was admitted to our hospital with maxillary gingival pain. A biopsy revealed well-differentiated oral squamous cell carcinoma(cT4aN0M0, Stage ⅣA). Hemi-maxillectomy was performed and postoperative recovery was uneventful. A maxillary prosthesis was provided for oral rehabilitation. At the 5-year follow-up, there were no signs of recurrence or metastasis. This case illustrates the importance of collaboration between oral maxillofacial surgeons and specialists from related departments for the comprehensive management of patients with mental retardation.

[A Case of Cavernous Sinus Metastasis following of the Postoperative Maxillary Gingival Carcinoma].

We report a case of cavernous sinus metastasis following postoperative maxillary gingival squamous cell carcinoma. An 83-year-old man was referred to our hospital due to pain in the left maxillary gingiva. Contrast-enhanced computed tomography imaging showed a mass lesion with bone destruction in the left maxillary gingiva. Biopsy indicated the presence of squamous cell carcinoma(T4bN1M0, Stage ⅣB), and the tumor was resected under general anesthesia. Four months after surgery, the patient experienced headache, and orbital pain, failing vision, and movement disorder of the left eye appeared. Magnetic resonance imaging revealed a tumor invading the cavernous sinus and orbit. The lesion was clinically diagnosed as metastatic cavernous sinus following postoperative left maxillary gingival carcinoma. Although the patient underwent chemotherapy, he died from multiple organ failure about 5 months after surgery.

[A Case of Lower Gingival Carcinoma Treated Surgically Using Computer-Assisted Patient-Specific Cutting Guide and Mandibular Reconstruction Plate].

We report a case of advanced lower gingival carcinoma treated with a computer-assisted custom-made surgical guide and reconstruction plate system(TruMatch®)in combination with a pectoralis major myocutaneous flap. In a 74-year-old male patient, a neoplastic lesion with a 30×30 mm periapical induration was observed around an extraction socket of left mandibular third molar. After various examinations, we diagnosed lower gingival carcinoma(cT4aN2bM0, Stage ⅣA). The patient was a paraplegic with a spinal cord injury, and reconstruction of mandible with free flap was not indicated, requiring minimally invasive surgery. Therefore, a surgical guide and reconstruction plate were prepared preoperatively using the Tru- Match® system. Under general anesthesia, the patient underwent tracheostomy, left modified radical neck dissection, segmental mandibulectomy, and reconstruction of the mandible using this system in combination with a pectoralis major myocutaneous flap. Postoperatively, the patient had minimal dysfunction. Currently, at 18 months follow up postoperatively, good prognosis was observed. In conclusion, this is a useful surgical system with accurate and less invasive surgery for segmental mandibulectomy of advanced lower gingival carcinoma.

Development and Validation of the Oral Health-Related Self-Efficacy Scale for Cancer Patients.

This study aimed to validate the Oral Health-related Self-Efficacy Scale for Patients with Cancer (OSEC), comprised of 17 questions (five factors). To this end, a sample of 203 cancer patients was recruited (August 2018-April 2019) followed by a random subsampling for test-retest reliability. Concurrent validity was tested by correlating scores with the Self-efficacy Scale for Advanced Cancer (SEAC), discriminant validity was tested by comparing high OSEC to low OSEC groups, and predictive validity was tested using a plaque control record. Five OSEC factors had Cronbach's alpha coefficients ranging from 0.75 to 0.88. The intraclass correlation coefficient of the total score was 0.92 upon test-retest reliability. The factor-level scores significantly related to all the SEAC factor-level scores. The differences between the high OSEC and low OSEC groups were statistically significant in the total score and on all factor-level scores (p < 0.01). The plaque control record of the high OSEC group was significantly lower than that of the low OSEC group (p < 0.01). In conclusion, the OSEC can be used for understanding cancer patients' motives for oral care behaviors and applied to program planning to increase self-efficacy and health behaviors.

[Functional Recovery following Incisional Cheiloplasty for Lower Labial Edema That Developed after Bilateral Neck Dissection and Postoperative Chemoradiotherapy-A Case Report].

We report a case of functional recovery following incisional cheiloplasty for the management of lower labial edema that developed after bilateral neck dissection with preservation of the one-side internal jugular vein and postoperative chemoradiotherapy. An 81-year-old woman underwent partial maxillectomy for the treatment of maxillary gingival cancer(squamous cell carcinoma, cT1N0M0, Stage Ⅰ)in April 2013. In July 2013, she underwent bilateral neck dissection(right, modified; left, radical)for bilateral cervical lymph node recurrence with an extra-nodal spread and received postoperative chemoradiotherapy( CDDP 75 mg/m2×3 course and total radiotherapy dosage of 66 Gy). Thereafter, the patient's condition progressed without recurrence or metastasis; however, the lower labium became edematous, and severe labial dysfunction was observed. Therefore, lower labial incisional cheiloplasty was performed under local anesthesia in October 2020. An excision area of 160×14 mm was determined on the inner side of the lower labium, and excision was performed with a steel blade scalpel. Lip closure became possible one week after the operation. Seven months after the operation, the patient recovered labial function and was satisfied with the outcome.

[A Case of Recurrent Squamous Cell Carcinoma of the Mandibular Gingiva Around a Mandibular Dental Implant].

Extensive bimaxillary bone support devices(hereafter referred to as a dental implant)are useful for morphological and functional reconstruction after resection of oral cancer. However, tumor recurrence due to peri-implantitis may occur. In this report, we describe a case of squamous cell carcinoma(SqCC)recurrence around a mandibular dental implant. An 80-year- old female patient underwent tumor resection and stratification for SqCC extending from the left lingual margin to the gingiva of the left lower molar in 2013. In 2014, 2 dental implants were placed in the bilateral mandibular canine region and a prosthetic device of implant-overdenture was installed. Six years after the primary tumor resection, a mass lesion was found in the peri-implant area of the left mandibular canine. Upon examination, the patient was diagnosed with SqCC recurrence and underwent radical tumor resection and immediate reconstruction using a submental flap and a reconstruction plate. Additional dental implants were concurrently placed in the remaining mandible. There was no evidence of recurrence, and the patient remains under careful observation so far.

[A Case of Polymorphous Low-Grade Adenocarcinoma of the Palate].

Polymorphous low-grade adenocarcinoma(PLGA)is a relatively rare low-grade adenocarcinoma of the minor salivary glands. If radical resection is performed, the prognosis is favorable. We present the case of a 62-year-old woman who presented to our clinic in April 2019 after noticing a mass on her palate. The intraoral examination revealed a 10-mm-diameter, well-defined, tender mass extending from the right hard palate to the soft palate. We suspected a benign tumor originating from the area of transition between the hard and soft palates. An excisional biopsy of the mass was performed, and PLGA was diagnosed on the basis of histopathologic findings. In May 2019, the tumor was resected under general anesthesia and a soft palatal lift prosthesis was applied for functional recovery. In July 2020, the soft palate defect was repaired using an ulnar forearm free flap during a two-stage reconstruction procedure. The patient developed complete necrosis of the free flap, and the defect was re-reconstructed using a buccinator-based myomucosal flap. There was no evidence of disease recurrence or metastasis. Two years have passed since the initial surgery, and the patient's clinical course has been well so far.

[Mass Screening of Oral Cancer in Eastern Shimane Prefecture during 2015-2019].

The Department of Oral and Maxillofacial Surgery, Shimane University Faculty of Medicine, has been conducting mass screening of oral cancer using oral abrasion cytology by oral surgeons in eastern Shimane prefecture for public awareness and its early detection. As a result, 3(0.09%)cases of oral cancer were identified. Case 1: The patient was diagnosed with well-differentiated squamous cell carcinoma in the floor of the mouth(pT1N0M0, Stage Ⅰ)after undergoing Matsue city oral cancer screening in 2016. Case 2: The patient underwent oral cancer screening in Izumo city in 2018 and was diagnosed with verrucous carcinoma in the back of the tongue(pT1N0M0, Stage Ⅰ). Case 3: The patient was diagnosed with highly differentiated squamous cell carcinoma of the palate(pT1N0M0, Stage Ⅰ)after undergoing the Izumo city oral cancer screening in 2019. Awareness of oral cancer is important, and cancer screening by oral surgeons using cytology is highly useful and should be continued in the future.

[A Clinical Study of Orofacial Defect Reconstruction Using a Modified Submental Island Flap following Oral Cancer Resection].

INTRODUCTION: Pedicled flaps are used in orofacial defect reconstruction in older patients and patients with underlying diseases. The submental island flap(SIF)is one type of cervical pedicled flap; however, the modified submental island flap (MSIF), which includes mylohyoid muscle, is a simpler and safer type. Here, we report a clinical study of orofacial defect reconstruction using the MSIF following oral cancer resection. PATIENTS AND METHODS: From January 2019 to December 2020, we retrospectively examined 10 cases of reconstruction using the MSIF following oral squamous cell carcinoma resection. RESULTS: The study population consisted of 7 men and 3 women with a mean age of 76.0(66-88)years. The primary sites were lower gingiva(n=5), tongue(n=3), and buccal mucosa in(n=2). Surgical procedures included marginal mandibulectomy( n=3), segmental mandibulectomy(n=1), partial glossectomy(n=2), hemiglossectomy(n=1), buccal mucosa resection(n=2), and combined partial glossectomy and segmental mandibulectomy(n=1). The average flap size was 61.4×36.0 mm. The average time of flap elevation was 32.4(23-50)minutes. During orofacial surgery using the MSIF, organs adjacent to the primary site could also be reconstructed. There were no complications in any patients. CONCLUSION: The MSIF is useful for orofacial defect reconstruction in older patients and patients with underlying diseases.

[A Case of Treatment Applicable to Squamous Cell Carcinoma of the Tongue by Mass Screening Examination of Oral Cancer in Western Part of the Shimane Prefecture].

Radical excision, a common oral cancer treatment, produces variable postoperative results depending on the specialized tissues involved and the extent of the cancer. Furthermore, the material selected for reconstruction also influences functional outcomes. Oral dysfunction due to postoperative tissue loss is more common with advanced cancer; therefore, early detection and treatment are important. To improve oral cancer awareness and early detection, mass oral cancer screenings led by maxillofacial surgeons in cooperation with the Shimane prefecture and local dental associations were conducted. We describe the mass screening methods and describe a case of tongue cancer that was detected and treated as a result of our screening efforts.

[A Case of Malignant Transformation of Previously Diagnosed Oral Leukoplakia].

Oral leukoplakia is the most common premalignant and potentially malignant lesion of the oral mucosa. Several studies have reported that the prevalence of oral cancer in young people is increasingly rapidly. The patient in this report was a 47- year-old man who complained of left tongue discomfort. At the first visit, the clinical diagnosis was oral leukoplakia, and a follow-up examination was planned with a view to partial resection. However, at the follow-up, biopsy revealed squamous cell carcinoma. He underwent partial resection. Two months after the surgery, metastasis to the lymph node was detected. The patient underwent radical neck dissection and concurrent chemoradiotherapy. At the 3-years follow-up, there was no sign of recurrence or metastasis.

[Secondary Maxillofacial Revision Reconstruction Using Custom-Made Artificial Bone Following Resection of Primary Intraosseous Mandibular Squamous Cell Carcinoma and Microvascularized Fibula Flap Reconstruction].

The basic treatment for oral cancer is radical tumor resection and reconstruction, which alters the maxillofacial morphology and causes dysfunction. Reconstructive surgery can be performed with bone and soft tissue transplantation, but it is invasive and good morphological repair is difficult. Custom-made artificial bone(CT-BoneTM)consisting of calcium-deficient hydroxyapatite was newly authorized for clinical use in April 2018. It enables precise, minimally invasive maxillofacial bone reconstruction. Here, we report favorable facial morphological improvement using CT-BoneTM in a patient with maxillofacial asymmetry following the resection of a primary intraosseous mandibular squamous cell carcinoma and microvascularized fibula flap reconstruction. The patient was a 52-year-old woman. In August 2010, she was diagnosed with primary intraosseous mandibular squamous cell carcinoma of the right mandible(T4aN0M0, Stage ⅣA)and underwent mandibular segmental resection, neck dissection, and free fibula flap reconstruction. Although her clinical course was uneventful, she wanted maxillofacial esthetic correction. Therefore, we performed maxillofacial revision reconstruction using computer-simulated custom-made CT-BoneTM in January 2020. It was stably fixed to the reconstructed mandible with bioactive/bioresorbable screws. The postoperative course was uneventful and maxillofacial symmetry was obtained to the patient's satisfaction at the 6 months follow-up.

[A Case of Early Detection and Treatment Applicable to Squamous Cell Carcinoma of the Palate Detected by Oral Cancer Mass Screening in Izumo 2019].

Treatment of oral cancer is based on radical resection and reconstructive surgery. Surgery causes impairment of maxillofacial morphology and function, including chewing and eating difficulties, and dysarthria. It is necessary to restore the maxillofacial morphology and function by reconstructive surgery and use of prostheses. Therefore, early detection and treatment are required to reduce these disabilities associated with oral cancers. Here, we report a case of oral cancer that was detected early by our oral cancer mass screening program in Izumo, Japan, in 2019. A 73-year-old woman presented with a reddish ulcerative region in the palate. Cytological screening indicated positive-suspected low squamous intraepithelial neoplasia (LSIL). The patient was diagnosed as squamous cell carcinoma of the palate(cT1N0M0, StageⅠ)in our hospital. We performed radical resection of the palate tumor and immediate reconstruction using a vascularized radial forearm flap. The clinical course was good and oral function was fully restored. It is important for oral surgeons to publicize and raise awareness of oral cancer, and to continue oral cancer mass screening programs.

[Surgical Procedure for Postoperative Reconstruction of Swallowing Function in a Very Elderly Patient with Advanced Tongue Cancer].

Surgical ablation and reconstruction are the first-line treatment strategies for squamous cell carcinoma of the tongue. However, locally advanced cases can be complicated by postoperative dysphagia. Here, we report a case of advanced tongue cancer in a very elderly patient who regained good swallowing function following a reconstructive surgery using a pectoralis major musculocutaneous flap with elevation of the hyoid bone. Case: An 89-year-old man diagnosed with advanced squamous cell carcinoma of the tongue(cT4aN2bM0, cStage ⅣA)underwent tracheostomy, right modified radical neck dissection type Ⅱ, left supraomohyoid neck dissection, subtotal glossectomy, and pectoralis major musculocutaneous flap reconstruction under general anesthesia. Intraoperatively, holes were created in the lower edge of the mandible, and the hyoid bone was suspended and fixed to the mandibular border using 2-0 nylon sutures. The postoperative course was uneventful. The flap had been completely engrafted and was in a good condition. The pharyngeal stage of swallowing function was reproduced through a reconstructive surgery with suspension and fixation of the hyoid bone toward the border of the mandible. Video fluorography 6 months postoperatively showed that good swallowing function was achieved using a palatal augmentation prosthesis.

Retrobulbar Orbital Emphysema Associated With Medial Orbital Wall Fracture.

Retrobulbar emphysema is a rare condition compared to the more common orbital emphysema. It is often associated with medial orbital wall fracture with rupture of the periosteum. In some severe patients, retrobulbar emphysema can increase the intraorbital pressure and lead to orbital compartment syndrome. Less extreme patients require only conservative treatment with careful observation. There is still no standard protocol for the management of orbital emphysema in general or specifically for retrobulbar emphysema. Visual acuity is the most widely used indicator to determine whether surgical intervention is needed. The patient presented here suffered from large retrobulbar intraconal emphysema and exophthalmos without visual loss after head trauma and nose blowing. He was observed closely without surgical intervention. After the emphysema had resolved, the patient's medial orbital wall defect was reconstructed using unsintered hydroxyapatite particles/poly L-lactide via the transcaruncular approach. The postoperative course has been uneventful with more than 1 year of follow-up to date.

[Oral Floor Reconstruction with Digastric Muscle Bipedicle Flap for Advanced Tongue Cancer in Very Elderly Patients-Report of Two Cases].

In recent years, the opportunity to treat oral cancer in elderly patients has been increasing because of the increased lifespan of individuals. Standard treatment for advanced tongue cancer involves reconstruction of the tongue with a free vascularized flap. However, this may not always be suitable for elderly patients because the procedure is lengthy and invasive and also because of their medical history. We report 2 cases of elderly patients undergone oral floor reconstruction with digastric muscle bipedicle flap for advanced tongue cancer. In case 1, an 86-year-old woman underwent pull-through ablation surgery with partial glossectomy and modified radical neck dissection for the treatment of left-sided tongue cancer(well-differentiated squamous cell carcinoma, cT3N2bM0, Stage ⅣA). In case 2, a 93-year-old man underwent pull-through ablation surgery with hemiglossectomy and suprahyoid neck dissection for treatment of right-sided tongue cancer(verrucous carcinoma, cT3N0M0, Stage Ⅲ). In both patients, the flap was sutured to the mandibular border, mandibular periosteum and surrounding tissue, and the intraoral mucosa and neck were isolated. Compared to the reconstruction of the tongue with a free vascularized flap, the procedure used in these 2 cases was shorter and caused less bleeding. Moreover, the patients exhibited no postoperative dysfunction, and clinical outcome remained favorable. We believe that oral floor reconstruction with digastric muscle bipedicle flap at the bottom of the mouth was effective in reducing surgical stress and restoring oral function in very elderly patients.

[A Case of Maxillary Gingival Carcinoma Possibly Caused by Chronic Inflammation Related to Oral Candidiasis].

Oral candidiasis infection is generally treated with antifungal agents. However, it often requires long-term treatment, and epithelial dysplasia may persist even after the infection has been resolved depending on the case. Malignant transformation has been reported in long-term cases involving chronic inflammation, and surgical excision should be performed as the treatment of choice when the treatment period is prolonged. This report describes a case of maxillary gingival carcinoma caused by chronic inflammation related to oral candidiasis. The patient was an 85-year-old man who was admitted to our hospital with maxillary gingival pain. Cytology and biopsy revealed oral candidiasis and squamous cell carcinoma(cT1N0M0, Stage Ⅰ). He underwent partial maxillectomy. Post-operative recovery was uneventful, and there was no sign of recurrence or metastasis at the 1-year follow-up.