SlicerPIT: software development and implementation for planning and image-guided therapy in photoimmunotherapy.

BACKGROUND: Photoimmunotherapy is a treatment modality that induces targeted cell death by binding a molecular-targeted drug activated by infrared light to the tumor cells and subsequently illuminating the lesion with infrared light. For deep lesions, a needle catheter is used to puncture the tumor, and an illumination fiber (cylindrical diffuser) is inserted into the catheter lumen for internal illumination. However, it can be challenging to place the cylindrical diffusers in an appropriate position as the deep lesions cannot be often confirmed accurately during surgery. MATERIALS AND METHODS: We have developed "SlicerPIT", a planning simulation software for photoimmunotherapy. SlicerPIT allows users to place the cylindrical diffuser with its illumination range on preoperative images in 2D and 3D and export the planning data to external image-guided surgical navigation systems. We performed seven cycles of photoimmunotherapy with SlicerPIT in three patients with recurrent head and neck cancer. RESULTS: Preoperative planning for photoimmunotherapy was conducted using SlicerPIT, which could be imported into the navigation system. During the operation, we punctured the needle catheters along with the treatment plan on the navigation screen. Subsequently, intraoperative CT imaging was performed and overlaid with the preoperative treatment plan to confirm the alignment of the cylindrical diffusers as planned, followed by infrared light illumination. Postoperative imaging showed necrosis and shrinkage of the entire tumor in all cycles. CONCLUSION: SlicerPIT allows for detailed preoperative treatment planning and accurate puncture. It may be a valuable tool to improve the accuracy of photoimmunotherapy for deep lesions and improve patient outcomes.

Targeted next-generation sequencing of Japanese patients with sinonasal mucosal melanomas identifies frequent NRAS and CTNNB1 mutations.

OBJECTIVE: Mucosal melanoma is a rare malignancy; however, the reported incidence rate of mucosal melanoma is higher in Asians than in Caucasians. Sinonasal mucosal melanoma (SNMM) is an aggressive malignancy with a poor prognosis due to distant metastasis. Systemic therapy with BRAF inhibitor and MEK inhibitor is one of the standards of care for cutaneous melanoma patients with BRAF V600 mutations. However, no molecular targeted therapy for patients with mucosal melanoma has been established. Relatively few studies have described the genetic mutations associated with mucosal melanoma because of its low frequency. Furthermore, to the best of our knowledge, the genetic mutations among Japanese patients have not been reported. Therefore, in the current study, we evaluated the genetic and clinicopathological characteristics of patients with SNMM. METHODS: A total of 18 tissue samples obtained from patients with SNMM were analyzed for genetic mutations based on targeted next-generation sequencing to investigate the driver of tumorigenesis and/or candidate genes for predicting clinical outcomes in SNMM. We also performed immunohistochemistry for patients identified with CTNNB1 mutations. RESULTS: Eight of the 18 (44 %) patients had genetic mutations. The most frequent mutation was NRAS (6/18, 33 %), followed by CTNNB1 (2/18, 11 %) and BRAF (1/18, 5.6 %). One patient had both NRAS and CTNNB1 mutations. Clinical outcomes did not differ significantly between those with and without genetic mutations. NRAS mutations were associated with relatively higher T classification and worse survival rates, although the differences were not significant. The nuclear translocation of ß-catenin was detected in both tumors with CTNNB1 mutations. The amino acid change in the BRAF mutation was K601R in exon 15. In the current study, no BRAF V600 mutations were detected. CONCLUSION: Genetic mutations were not significantly associated with clinical outcomes. However, NRAS mutations may be a prognostic predictor and CTNNB1 mutation may be a treatment effector for immune check inhibitors. A larger prospective study is required to clarify the clinical importance of genetic mutations in patients with SNMM.

Nasopharyngeal Carcinoma Treated With Photoimmunotherapy.

Photoimmunotherapy is a new treatment modality in which a tumor-targeting monoclonal antibody is combined with a photoactivated dye and a laser is applied to destroy tumor cells. In Japan, insurance reimbursement for this treatment started in January 2021 for unresectable locally advanced or locally recurrent head and neck cancer. We used photoimmunotherapy to treat two patients with recurrent nasopharyngeal squamous cell carcinoma (NPSCC). The first patient was diagnosed with NPSCC (T1N0M0) and treated with definitive radiotherapy, leading complete response. A local recurrence was observed and treated with photoimmunotherapy. Seven months have passed, complete response is archived. The second patient was diagnosed with NPSCC (cT2N1M1). Multimodal therapy led to a complete response for all lesions. A local recurrent lesion appeared, and photoimmunotherapy has been repeatedly performed. The lesion was controlled as a stable disease for about one year. Photoimmunotherapy could be an effective treatment for local recurrence of NPSCC after radiotherapy.

Salvage surgery improves the treatment outcome of patients with residual/recurrent maxillary sinus cancer after superselective intra-arterial cisplatin infusion with concomitant radiation therapy.

PURPOSE: We have performed superselective intra-arterial cisplatin infusion with concomitant radiotherapy (RADPLAT) for patients with maxillary sinus cancer. The promising treatment outcomes of this non-surgical treatment were reported in past studies. However, few clinical studies have been conducted to evaluate the outcome of salvage surgery following RADPLAT. The purpose of this study was to analyze the treatment outcomes of salvage surgery for patients with recurrent maxillary sinus cancer after RADPLAT. METHODS: We assessed 45 patients who had recurrence following RADPLAT between 1999 and 2017, and conducted a retrospective analysis. We excluded patients who did not complete RADPLAT. Patients were not considered to have completed RADPLAT if they underwent intra-arterial cisplatin less than three times or received a total radiation dose of less than 60 Gy. The primary endpoint was overall survival. The median follow-up period for surviving patients after recurrence was 5.1 years. RESULTS: Twenty-five of the 45 (56%) patients underwent salvage surgery. The 5-year overall survival rate was 68% in patients who underwent salvage surgery, while all patients who did not undergo salvage surgery died during the observation period. Fifteen of 24 (63%) patients with local recurrence underwent salvage surgery. Eight patients did not undergo salvage surgery because of unresectable disease; five of the eight patients had unresectable posterior extension. All nine patients with nodal recurrence underwent neck dissection. CONCLUSION: Treatment outcomes of salvage surgery following RADPLAT were favorable enough for it to be generally recommended. To reduce unresectable recurrence, the posterior section should be eradicated by RADPLAT.

Predictors of the need for prophylactic percutaneous endoscopic gastrostomy in head and neck cancer patients treated with concurrent chemoradiotherapy.

BACKGROUND: We investigated whether prophylactic percutaneous endoscopic gastrostomy (PEG) is used effectively for patients treated with definitive concurrent chemoradiotherapy (CCRT) and the predictors of the need for PEG. METHODS: 326 patients with laryngeal, oropharyngeal or hypopharyngeal cancers were retrospectively reviewed. RESULTS: The PEG tube use group had more favorable results than the total parenteral nutrition and nasogastric tube groups in terms of rate of serum albumin loss, incidence of severe fever and aspiration pneumonia, CCRT completion rate and hospitalization period. However, it was inferior to oral intake. Analysis of the relative risk of requiring enteral or parenteral nutrition revealed that performance status (PS) 2, primary site (supraglottis, oropharynx, or hypopharynx), N3 disease, and cisplatin were predictors of the need for nutritional support. CONCLUSIONS: Prophylactic PEG is effective for patients treated with definitive CCRT and is especially required for patients with PS2 or oropharyngeal cancer.

Pathological evaluation of the accuracy of a fluorescence spectroscopy system for detecting parathyroid glands.

PURPOSE: A fluorescence-based technique for the detection of parathyroid glands (PGs) intraoperatively was previously reported. The technique was based on the phenomenon in which PGs emit autofluorescence when exposed to near-infrared light and we undertook an evaluation to consider the pathological accuracy of the method. METHODS: The study comprised 17 patients (18 specimens) who underwent thyroid surgery at Kushiro City General Hospital between November 2018 and June 2019. We searched for PGs intraoperatively using a fluorescence spectroscopy system and evaluated the pathological accuracy of the system. We statistically evaluated the clinical factors associated with the accuracy of the system, including age, gender, body mass index, laterality, disease state, renal function, and comorbidity. RESULTS: Eighteen specimens were evaluated pathologically, with 13 specimens confirmed as PGs. These were evaluated as "true positive," giving a positive predictive value of 72.2% (13/18). Among the false-negative cases, one specimen was a metastatic lymph node in a patient with papillary thyroid carcinoma. There was a significant difference in the true-positive rates between malignant (25%) and benign (85.7%) disease (P = 0.044). CONCLUSION: We consider that this technique is useful, however, we have to exercise care in malignant cases as the true-positive rate may be low.

A novel study for fluorescence patterns of the parathyroid glands during surgery using a fluorescence spectroscopy system.

PURPOSE: Recently it was reported that the parathyroid glands (PGs) emit autofluorescence when exposed to near infrared light, and a technique using fluorescence to detect the PGs intraoperatively was found to be useful. In some cases, however, it was difficult to detect the PGs. We sought to clarify the situation regarding such undetectable cases. METHODS: The study comprised 45 patients (50 sides) who underwent thyroid or parathyroid surgery at Kushiro city general hospital between November 2018 and June 2019. We searched for the PGs intraoperatively using a fluorescence spectroscopy system. We statistically considered the factors related to the fluorescence patterns of background in cases in which two PGs could not be confirmed using Fisher's exact test. Factors included age, gender, body-mass index, laterality, disease state, renal function, and comorbidity. RESULTS: In 41 sides (82%) fluorescence from at least one PG was determined. There was no significant difference in the detection rates among the other clinical factors. A "White out" pattern in which the background was too bright to detect PGs was observed in 11 sides (22%), and a "Black out" pattern in which the background and PGs were dark was observed in 18 sides (36%). Malignant disease was statistically associated with a "White out" pattern. No factors were found to be related to the "Black out" pattern. CONCLUSION: In malignant disease, we should use this novel approach carefully.