General rules for clinical and pathological studies on oral cancer (2nd edition): a synopsis.

For doctors and other medical staff treating oral cancer, it is necessary to standardize the basic concepts and rules for oral cancer to achieve progress in its treatment, research, and diagnosis. Oral cancer is an integral part of head and neck cancer and is treated in accordance with the general rules for head and neck cancer. However, detailed rules based on the specific characteristics of oral cancer are essential. The objective of this article was to contribute to the development of the diagnosis, treatment, and research of oral cancer, based on the correct and useful medical information of clinical, surgical, pathological, and imaging findings accumulated from individual patients at various institutions. Our general rules were revised as the UICC was revised for the 8th edition and were published as the Japanese second edition in 2019. In this paper, the English edition of the "Rules" section is primarily presented.

Stability of daily rectal movement and effectiveness of replanning protocols for sparing rectal doses based on the daily CT images during proton treatment for prostate cancer.

PURPOSE: To evaluate the optimal period of replanning to spare the rectal dose by investigating daily rectal movements during computed tomography (CT) image-guided proton therapy for prostate cancer. MATERIALS AND METHODS: To evaluate the optimum reference period for replanning, we analyzed 1483 sets of daily CT (dCT) images acquired from 40 prostate cancer patients and measured the daily rectal movement along the anterior-posterior direction based on the simulator CT (sCT) images and dCT images. We calculated daily dose distributions based on initial plans on the sCT images and replans on the dCT images for 13 representative patients, and evaluated daily dose volume histograms (DVHs) for the prostate, seminal vesicles, and rectum. RESULTS: The rectal anterior side on the dCT images around the seminal vesicles largely deviated toward the anterior side relative to the position on the reference sCT images, but the deviation decreased by referring to the dCT images and became nearly zero when we referred to the dCT images after 10-day treatment. The daily DVH values for the prostate showed good dose coverage. For six patients showing rectal movement toward the anterior side, the daily rectal DVH (V77% ) showed a 3.0 ± 1.7 cc excess from the initial plan and this excess was correlated with 9.9 ± 6.8 mm rectal movement. To identify the patients (37.5% in total) for whom the replanning on the 10th-day and 20th-day CT images reduced the V77% excess to 0.4 ± 1.5 cc and -0.2 ± 1.3 cc, respectively, we evaluated the accumulated mean doses with a 1.2 cc criterion. CONCLUSION: Our data demonstrate that the daily movement of the rectal anterior side tends to move toward the anterior side, which results in a rectal overdose, and the mean of the movement gradually decreases with the passage of days. In such cases, replanning with the reference CT after 10 days is effective to spare the rectal dose.

Preliminary results of proton beam therapy combined with weekly cisplatin intra-arterial infusion via a superficial temporal artery for treatment of maxillary sinus carcinoma.

OBJECTIVE: This study aimed to evaluate the efficacy and toxicity of proton beam therapy combined with cisplatin intra-arterial infusion via a superficial temporal artery as treatment for maxillary sinus carcinoma. METHODS: Twenty-six patients with confirmed maxillary sinus carcinoma were enrolled in this study from May 2009 to April 2011. Patients underwent proton beam therapy and intra-arterial infusion chemotherapy with cisplatin. RESULTS: The median total dose was 70.4 GyE per 32 fractions, and the median dose of cisplatin was 300 mg/body for six cycles of intra-arterial infusion. The 3-year overall survival rate was 58% for all patients (n = 26), 58% for patients with stage T4 disease (n = 12), 57% for patients with

Carbon ion radiotherapy for desmoid tumor of the abdominal wall: a case report.

BACKGROUND: Desmoid tumors, which are associated with familial adenomatous polyposis (FAP), tend to occur frequently in the abdominal wall and mesentery. Currently, there are no recognized treatments other than surgery, and frequent surgeries result in gastrointestinal obstructions and functional gastrointestinal disorders. CASE PRESENTATION: After surgery that was performed on a 39-year-old patient with FAP, we performed a second tumor excision which was the procedure used for frequently occurring mesenteric desmoid tumors. It was determined that the enlarged tumor would be difficult to operate on through an abdominal incision. Subsequently, the carbon ion radiotherapy of 50 Gy was then performed on the patient. Three years later, the tumor still remains reduced in size. In addition, we have not observed any negative effect on the digestive tract. CONCLUSIONS: This is the first instance that the carbon ion radiotherapy has been effective for the unresected desmoid tumor, and it is believed that this will become the one effective option for the treatment of desmoid tumors.

High-dose proton beam therapy for stage I non-small cell lung cancer: Clinical outcomes and prognostic factors.

BACKGROUND: Evidence has suggested that radiation therapy with a lower dose per fraction may be a reasonable option for the treatment of centrally located non-small cell lung cancer (NSCLC). The aim of this study was to evaluate the safety and efficacy of two proton beam therapy (PBT) protocols for stage I NSCLC and to determine prognostic factors. MATERIAL AND METHODS: This study included patients clinically diagnosed with stage I NSCLC. Based on the location of the tumor, one of the two PBT protocols was administered. Patients with peripherally located tumors were given 66 Gy relative biological dose effectiveness (RBE) over 10 fractions (Protocol A) while patients with centrally located tumors were given 80 Gy (RBE) over 25 fractions (Protocol B). RESULTS: Between January 2009 and May 2012, 56 eligible patients were enrolled (protocol A: 32 patients; protocol B: 24 patients). The three-year overall survival (OS), progression-free survival (PFS), and local control (LC) rates were 81.3% [95% confidence interval (CI) 75.9-86.7%], 73.4% (95% CI 67.2-79.6%), and 96.0% (95% CI 93.2-98.8%), respectively. There were no significant differences in outcomes between the two protocols. Late grade 2 and 3 pulmonary toxicities were observed in nine patients (13.4%) and one patient (1.5%), respectively; no grade 4 or 5 toxicities were observed. Sex, age, performance status, T-stage, operability, and tumor pathology were not associated with OS and PFS. Only maximum standardized uptake value (SUVmax; <5 vs. ≥5) was identified as a significant prognostic factor for OS and PFS. CONCLUSION: Both high-dose PBT protocols achieved high LC rates with tolerable toxicities in stage I NSCLC patients, and SUVmax was a significant prognostic factor.

Particle therapy for clinically diagnosed stage I lung cancer: comparison with pathologically proven non-small cell lung cancer.

BACKGROUND: The purpose of the present study was to present the treatment outcomes of particle therapy for indeterminate pulmonary nodules (IPNs) diagnosed as stage I non-small cell lung cancer, including a comparative analysis involving pathologically proven lung cancer (PPLC). MATERIAL AND METHODS: A total of 54 patients (57 lesions) who underwent particle therapy for IPNs were enrolled in this study. Median patient age was 76 (range 52-87) years. T-classification was: T1a, 30; T1b, 16; and T2a, 11. Particle therapy using protons or carbon ions was delivered at total doses of 52.8-80 Gy equivalent in 4-26 fractions. The PPLC cohort included 111 patients. RESULTS: The median follow-up time was 41 (range 7-90) months. For all IPN patients, the three-year overall survival, progression-free survival, local control and distant progression-free survival rates were 90%, 72%, 94% and 79%, respectively. Grade 2 toxicities were radiation pneumonitis (19%), dermatitis (9%), rib fracture (2%), chest wall pain (2%) and neuropathy (2%). No ≥grade 3 toxicities were observed. In univariate analysis, the IPN group showed significantly better survival relative to the PPLC group. However, after adjustment for baseline imbalances between these two groups in multivariate analysis, pathological confirmation did not correlate with survival. CONCLUSIONS: Particle therapy for IPNs provided favorable outcomes with minimal toxicities, which may be comparable to those for PPLC patients. Further studies are needed to clarify the optimal management of IPN patients.

Unexpected radiation laryngeal necrosis after carbon ion therapy using conventional dose fractionation for laryngeal cancer.

Carbon ion therapy is a type of radiotherapy that can deliver high-dose radiation to a tumor while minimizing the dose delivered to organs at risk. Moreover, carbon ions are classified as high linear energy transfer radiation and are expected to be effective for even photon-resistant tumors. A 73-year-old man with glottic squamous cell carcinoma, T3N0M0, refused laryngectomy and received carbon ion therapy of 70 Gy (relative biological effectiveness) in 35 fractions. Three months after the therapy, the patient had an upper airway inflammation, and then laryngeal edema and pain occurred. Five months after the therapy, the airway stenosis was severe and computed tomography showed lack of the left arytenoid cartilage and exacerbation of laryngeal necrosis. Despite the treatment, 5 and a half months after the therapy, the laryngeal edema and necrosis had become even worse and the surrounding mucosa was edematous and pale. Six months after the therapy, pharyngolaryngoesophagectomy and reconstruction with free jejunal autograft were performed. The surgical specimen pathologically showed massive necrosis and no residual tumor. Three years after the carbon ion therapy, he is alive without recurrence. The first reported laryngeal squamous cell carcinoma case treated with carbon ion therapy resulted in an unexpected radiation laryngeal necrosis. Tissue damage caused by carbon ion therapy may be difficult to repair even for radioresistant cartilage; therefore, hollow organs reinforced by cartilage, such as the larynx, may be vulnerable to carbon ion therapy. Caution should be exercised when treating tumors in or adjacent to such organs with carbon ion therapy.

Clinical efficacy of alternating chemoradiotherapy by conformal radiotherapy combined with intracavitary brachytherapy for high-risk cervical cancer.

OBJECTIVE: The purpose of this study was to assess the outcome of alternating chemoradiotherapy in patients with high-risk cervical cancer. METHODS: We performed definitive alternating chemoradiotherapy in cervical cancer patients with at least one high-risk factor such as International Federation of Gynecology and Obstetrics III or IVA disease, primary tumor diameter ≥50 mm, positive pelvic node, and positive para-aortic node. Our chemoradiotherapy protocol was as follows: (i) alternating chemoradiotherapy with 5-fluorouracil and nedaplatin; (ii) whole pelvic radiotherapy with the dynamic conformal technique combined with intracavitary brachytherapy; (iii) prophylactic irradiation to the para-aortic region for International Federation of Gynecology and Obstetrics III/IVA or positive pelvic node and full-dose radiotherapy for positive para-aortic node. Between 1998 and 2010, 121 patients were treated with this protocol. RESULTS: The median follow-up period was 53.7 months (7.6-162.2). International Federation of Gynecology and Obstetrics stages were IB; (9.1%), IIA; 6 (5.0%), IIB; 53 (43.8%), IIIA; 7 (5.8%), IIIB; 37 (30.6%) and IVA; 7 (5.8%), respectively. Nodal involvement was reported in 77 patients (63.6%) at the pelvis and 25 (20.7%) at the para-aortic region. The 5-year overall survival and progression-free survival rates were 80.0 and 63.4%, respectively. Regarding Grade ≥3 late toxicities, three patients developed urinary and three developed intestinal toxicities. We encountered no treatment-related death. CONCLUSIONS: The clinical results of our alternating chemoradiotherapy protocol for high-risk cervical cancer are promising.

Particle radiotherapy using protons or carbon ions for unresectable locally advanced head and neck cancers with skull base invasion.

OBJECTIVE: To study the oncological outcome of the patients with unresectable locally advanced primary head and neck cancers invading the skull base, treated with particle radiotherapy. METHODS: Fifty-seven patients with unresectable primary head and neck cancers invading the skull base received proton or carbon ion radiotherapy as definitive treatment at Hyogo Ion Beam Medical Center between 2003 and 2009. Forty-seven patients were treated with proton radiotherapy and 10 patients were treated with carbon ion radiotherapy. A retrospective review was performed with clinical charts and recorded imagings. RESULTS: With a median follow-up of 32 months, the 3-year actual survival and local progression-free rates of all the patients were 61 and 56%, respectively. The 3-year actual survival rates of adenoid cystic carcinoma, squamous cell carcinoma, olfactory neuroblastoma, adenocarcinoma and malignant melanoma were 83, 44, 75, 0 and 38%, respectively. The 3-year actual local control rates of adenoid cystic carcinoma, squamous cell carcinoma, olfactory neuroblastoma, adenocarcinoma and malignant melanoma were 63, 31, 83, 50 and 0%, respectively. Distant metastasis was observed in 13 of 25 patients in adenoid cystic carcinoma, two of 14 patients in squamous cell carcinoma, one of six patients with olfactory neuroblastoma, two of four patients with adenocarcinoma, three of four patients with malignant melanoma and two of three patients with undifferentiated carcinoma. Mucositis and dermatitis were seen as acute toxicities. The most common late toxicity was visual disorder. Grades 2, 3 and 4 visual disorders were observed in seven, five and two patients, respectively. CONCLUSIONS: Proton and carbon ion radiotherapy resulted in satisfactory local control in patients with locally advanced unresectable primary head and neck cancers invading the skull base.

Local Low-dose Anti-PD-L1 Antibodies Improve Antitumor Effects in Oral Squamous Cell Carcinoma.

BACKGROUND/AIM: Immune checkpoint inhibitors are highly effective for treating recurrent and metastatic head and neck cancers. However, they require systemic administration and are associated with immune-related adverse events (irAEs). Reducing therapeutic antibody doses to prevent irAEs is challenging. MATERIALS AND METHODS: Mouse buccal mucosa squamous cell carcinoma cells (Sq-1979) were transplanted into the backs of mice to induce tumors. The antitumor efficacy and tumor immunohistological environment in tumor-bearing mice were compared after administering a standard dose of programmed death-ligand 1 (PD-L1) antibodies systemically (200 mg/body) or 1/10th of the standard dose (20 mg/body) directly to tumors. Mice received four doses of antibody administered in 3-day intervals. Tumor reduction rates and antitumor efficacies were evaluated 21 days after initiating treatment. CD8+T cell counts and PD-L1, PD-1, perforin, and granzyme B levels; CD25 and Foxp3 expression levels; and tumor Tregs were assessed in the resected subcutaneous tumors. RESULTS: The antitumor efficacies in the local low-dose and systemic standard-dose groups were compared with that of the control group. The efficacies of the two treatment groups were similar, and both treatment groups revealed significant antitumor effects compared to the control group. Perforin and granzyme B levels were higher in the local low-dose group (p<0.05). CONCLUSION: Local low-dose administration of anti-PD-L1 antibodies exhibits antitumor efficacy similar to systemic standard-dose administration suggesting that local low-dose administration is useful for treating oral squamous cell carcinoma.

Thyrolinguofacial trunk arising from the carotid bifurcation determined by three-dimensional computed tomography angiography.

It is recognized that the branches of the external carotid artery (ECA) can show variation, but the presence of a thyrolinguofacial trunk is extremely rare and always originates from the ECA. We report a case of the thyrolinguofacial trunk arising from the carotid bifurcation (CB) on the left side in a 76-year-old man with advanced tongue cancer, as revealed by three-dimensional computed tomography angiography for vascular mapping of the carotid vessels prior to superselective intra-arterial catheterization. The thyrolinguofacial trunk arose 1.6 mm below the CB from the anterior surface of the left CB. The inner diameter of the thyrolinguofacial trunk at origin was 4.4 mm and the angle between the thyrolinguofacial trunk and CB was 128°. After a 1.7-mm course, the trunk divided into the superior thyroid artery and a linguofacial trunk, the inner diameters of which were 1.5 and 3.4 mm, respectively, at origin. The angle between the two arteries was 88°. After a 9.8-mm course from the bifurcation, the linguofacial trunk divided into the lingual artery and facial artery, the inner diameters of which were 1.8 and 1.9 mm, respectively, at origin. The angle between the two arteries was 61°. It is important to recognize such an anatomic variation of the branches of the ECA prior to superselective intra-arterial catheterization or microsurgical reconstruction for head and neck cancer.

[Analysis of the safety and efficacy of percutaneous isolated hepatic perfusion after particle therapy for advanced hepatocellular carcinoma].

Here, we report the efficacy of dual treatment with hepatic resection and percutaneous isolated hepatic perfusion (PIHP) for advanced hepatocellular carcinoma( HCC). Recently, we introduced treatment with combined particle therapy and PIHP for unresectable HCC in cases of insufficient liver function. The purpose of this study was to evaluate the safety and efficacy of PIHP for local control in the liver after particle therapy. From 2006 to 2013, 6 patients underwent particle therapy for the main lesion and subsequent PIHP for remnant liver lesions. Their mean age was 64 years, and the mean size of the main lesion was 6.2 cm (range, 2.0-10.8 cm). All patients had liver cirrhosis. After particle therapy, PIHP was performed by hepatic arterial infusion of 100 mg/m2 of doxorubicin and 30 mg/m2 of mitomycin C. With regard to side effects, neutropenia occurred in all patients but no serious hepatobiliary injury was observed. The response rate for PIHP was 50% (partial response: 3 and stable disease: 3). The mean overall survival time was 26.9 months after particle therapy. In conclusion, even after particle therapy, PIHP is a safe treatment and is associated with a good local control rate for remnant HCCs. Further accumulation of data is needed to evaluate the efficacy of this treatment strategy in terms of prognosis.

[A case of superior sulcus tumor treated with carbon ion radiotherapy].

Superior sulcus tumor( SST) is a rare type of lung cancer. Treatment usually consists of surgical resection after chemoradiotherapy. We report a case of a woman in her fifties who underwent carbon ion radiotherapy for SST. The patient complained of left shoulder pain, and imaging studies revealed a 5.2×3.5-cm local solid tumor at the apex of the left lung, invasion to the ribs, and no lymph node swelling. The level of tumor marker, carcinoembryonic antigen (CEA), was 5.7 ng/mL. Needle biopsy specimen revealed adenocarcinoma. The diagnosis was SST, T3N0M0, stage IIB. We did not detect Horner syndrome. Carbon ion radiotherapy at 66 Gy equivalent dose per 10 fractions was administered to the SST site. Subsequently, the tumor size decreased to 4.5×1.9-cm. The adverse effect was Grade 1 skin and pulmonary toxicity. Six months later, Grade 2 left shoulder connective tissue toxicity was observed; it was difficult to differentiate this from tumor recurrence. After 2.5 years from radiotherapy, the patient is free from recurrence. Carbon ion radiotherapy is effective and safe and can be considered as an important treatment option for SST.

The ECAS system can superselectively administer anticancer drugs to numerous feeding arteries from the superficial temporal artery: A case report and literature review.

Superselective intra-arterial chemoradiotherapy (SSIACRT) is one of the curative treatments for advanced oral cancer. SSIACRT can reportedly treat cervical lymph node metastases in the level I-IIA area by super selectively catheterizing the facial artery (FA) and infusing drugs. However, since advanced oral cancer lesions involve a number of feeding vessels, retrograde treatment requires the placement of catheters from the superficial temporal artery (STA) and occipital artery (OA). Furthermore, in the case of level IIB lymph node metastasis, the catheter must be changed because it is necessary to administer anticancer drugs to more than three routes, including the OA, when the feeding arteries of the primary tumor are combined. The external carotid artery sheath (ECAS) system used in the present study involves the insertion of a microcatheter or steering catheter from one route of the STA, allowing selection of numerous feeding vessels, including the OA. The ECAS system can facilitate the administration of chemotherapy via the STA simultaneously to the maxillary artery, lingual artery, FA and OA. The present study describes cases of maxillary gingival cancer and tongue cancer with cervical lymph node metastasis, which were treated with the ECAS system via the STA; the treatment successfully controlled both the primary tumor and cervical lymph node metastasis. In the two cases described in the present study, metastatic lymph nodes were found in the level ⅠB and ⅡB region, but were successfully treated by administering cisplatin via the OA, in addition to the primary lesion. To date, to the best of our knowledge, there is no case report clearly referring to the treatment of lymph node metastasis using the ECAS system. In conclusion, SSIACRT using ECAS may be considered a useful treatment for oral cancer with cervical lymph node metastasis.

Endoscopic Laryngopharyngeal Surgery Combined with Endoscopic Submucosal Dissection as a Treatment Option for Superficial Hypopharyngeal Cancer with Suspected Synchronous Lymph Node Metastasis.

We report 4 cases of hypopharyngeal cancer preoperatively suspected with synchronous lymph node metastases. Pathologic lymph node metastasis was confirmed in three of the four cases. All 4 cases underwent endoscopic laryngopharyngeal surgery (ELPS) combined with endoscopic submucosal dissection (ESD) and subsequent lymph node dissection as an optional treatment rather than the standard treatment. Peroral resection for primary site was selected because of the expected decline in quality of life (QoL) after radical surgery. Among 4 patients, one developed local recurrence; however, the other three remained recurrence-free and survived without any additional treatment. Furthermore, the patient who developed local recurrence had a recurrence-free survival for more than 5 years, with additional chemoradiation therapy. No disorders in speech, swallowing, or breathing was observed during the follow-up period. ELPS combined with ESD is generally indicated for laryngopharyngeal cancer without synchronous lymph node metastasis. However, this can be a treatment option for patients may wish to preserve a greater QoL after treatment. In the future, when more data on the results and long-term prognosis of this treatment are accumulated, it may be possible to discuss its validity further.

Analysis of carotid artery deformation in different head and neck positions for maxillofacial catheter navigation in advanced oral cancer treatment.

BACKGROUND: To improve the accuracy of catheter navigation, it is important to develop a method to predict shifts of carotid artery (CA) bifurcations caused by intraoperative deformation. An important factor affecting the accuracy of electromagnetic maxillofacial catheter navigation systems is CA deformations. We aimed to assess CA deformation in different head and neck positions. METHODS: Using two sets of computed tomography angiography (CTA) images of six patients, displacements of the skull (maxillofacial segments), C1-C4 cervical vertebrae, mandible (mandibular segment), and CA along with its branches were analyzed. Segmented rigid bones around CA were considered the main causes of CA deformation. After superimposition of maxillofacial segments, C1-C4 and mandible segments were superimposed separately for displacement measurements. Five bifurcation points (vA-vE) were assessed after extracting the CA centerline. A new standardized coordinate system, regardless of patient-specific scanning positions, was employed. It was created using the principal axes of inertia of the maxillofacial bone segments of patients. Position and orientation parameters were transferred to this coordinate system. CA deformation in different head and neck positions was assessed. RESULTS: Absolute shifts in the center of gravity in the bone models for different segments were C1, 1.02 ± 0.9; C2, 2.18 ± 1.81; C3, 4.25 ± 3.85; C4, 5.90 ± 5.14; and mandible, 1.75 ± 2.76 mm. Shifts of CA bifurcations were vA, 5.52 ± 4.12; vB, 4.02 ± 3.27; vC, 4.39 ± 2.42; vD, 4.48 ± 1.88; and vE, 2.47 ± 1.32. Displacements, position changes, and orientation changes of C1-C4 segments as well as the displacements of all CA bifurcation points were similar in individual patients. CONCLUSIONS: CA deformation was objectively proven as an important factor contributing to errors in maxillofacial navigation. Our study results suggest that small movements of the bones around CA can result in small CA deformations. Although patients' faces were not fixed properly during CT scanning, C1-C4 and vA-vE displacements were similar in individual patients. We proposed a novel method for accumulation of the displacement data, and this study indicated the importance of surrounding bone displacements in predicting CA bifurcation.

Thyrolingual trunk arising from the common carotid artery identified by three-dimensional computed tomography angiography.

It is well-known that the branches of the external carotid artery (ECA) can show anatomical variation, but it is extremely rare that thyrolingual trunk originates from common carotid artery (CCA). Here we report a case of the thyrolingual trunk arising from the CCA on the right side in a 73-year-old female as revealed by three-dimensional computed tomography angiography for vascular mapping of the carotid vessels before head and neck microsurgical reconstruction. The thyrolingual trunk arose from the anterior surface of the right CCA, with an origin 14.5 mm (difference between the carotid bifurcation and upper border of the origin 12.7 mm) below the carotid bifurcation. The inner diameter of origin of the thyrolingual trunk was 3.5 mm, and the angle between the thyrolingual trunk and the CCA was 130°. After a 10.2-mm course, the thyrolingual trunk divided into the superior thyroid artery (STA) and lingual artery (LA). The inner diameters of the origins of the STA and LA were 1.7 and 1.9 mm, respectively, and the angle between the branches was 94°. It is important to recognize this anatomic variation of the branches of the ECA before the microsurgical reconstruction or super-selective intra-arterial chemotherapy for head and neck cancer.

Intratumor hemodynamics using contrast-enhanced MRI in intra-arterial chemotherapy for head and neck cancer.

OBJECTIVE: The objectives of the study were to estimate the perfusion of tumors by drugs used in intra-arterial chemotherapy for head and neck cancer with magnetic resonance imaging and to establish the factors involved in determining the optimal dose. STUDY DESIGN: Contrast agent was administered intra-arterially into either the lingual or maxillary artery in 43 patients. Triple-phase continuous fast spin echo magnetic resonance imaging was performed. Changes in blood water longitudinal relaxation rate (⊿R1) were measured in relation to imaging phase, type of artery, measurement site, and tumor size. RESULTS: ⊿R1 was significantly higher at the tumor margin than at the center for both arteries, except in the first phase for the lingual artery. ⊿R1 was greatest in the third phase for the lingual artery and in the second phase for the maxillary artery. For both arteries, as the tumor size increased, there was a significant decrease in ⊿R1 at the center of the tumor compared with the margin. CONCLUSIONS: The factors associated with ⊿R1 were imaging phase, type of artery, measurement site, and tumor size. When determining a drug's optimal dose, the type of artery and tumor size must be taken into consideration.

Initial Experience of Intra-Arterial Chemotherapy Using a Novel External Carotid Arterial Sheath System Combined with Radiotherapy and Systemic Chemotherapy for Locally Advanced Tongue Cancer.

We retrospectively evaluated the safety and effectiveness of an external carotid arterial sheath (ECAS) for intra-arterial chemotherapy (IACT) for locally advanced tongue cancer. Thirty-one patients with the Union for International Cancer Control's 8th TNM stage III-IV tongue cancer underwent IACT using the ECAS combined with RT and systemic chemotherapy with either cisplatin and fluorouracil (FP) or docetaxel, cisplatin, and fluorouracil (TPF) between October 2015 and February 2021. The ECAS was inserted retrogradely via the superficial temporal artery, and the tip was placed in the external carotid artery between the maxillary and facial arteries. A microcatheter was inserted into each tumor-feeding artery through the ECAS under fluoroscopy, wherein cisplatin 50 mg/m2 was administered. IACT was performed weekly with neutralization using sodium thiosulfate. Complete response of the primary lesion was achieved in 28/31 (90%) patients. The median follow-up for all patients was 39 months. The 3-year overall survival, progression-free survival, and local control rates were 81.6%, 74.2%, and 83.4%, respectively. Grade 3 and greater toxicities included oral mucositis (45%), neutropenia (39%), nausea (13%), anemia (10%), thrombocytopenia (10%), dry mouth (10%), and fever (3%). There were no severe complications associated with IACT. In conclusion, the ECAS is feasible and effective for locally advanced tongue cancer.