Common progenitor origin for Rosai-Dorfman disease and clear cell sarcoma.

Histiocytic neoplasms (HNs) in adults have been reported to be associated with a high prevalence of coexisting haematological and solid malignancies. While a proportion of coexisting HNs and haematological malignancies share identical genetic alterations, the genetic association between HNs and solid malignancies has scarcely been reported. We report a case of Rosai-Dorfman disease (RDD) complicated by coexisting clear cell sarcoma (CCS). RDD is a rare HN. CCS is an ultrarare soft tissue sarcoma with a poor prognosis. Mutation analysis with whole-exome sequencing revealed six shared somatic alterations including NRAS p.G12S and TP53 c.559+1G>A in both the RDD and CCS tissue. This is the first evidence of a clonal relationship between RDD and solid malignancies using mutational analysis. We hypothesise that neural crest cells, which originate in CCS, are likely the common cells of origin for RDD and CCS. This case helps to unravel the underlying clinicopathological mechanisms of increased association of solid malignancies in HNs. © 2024 The Author(s). The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Antibiotics May Interfere with Nivolumab Efficacy in Patients with Head and Neck Squamous Cell Carcinoma.

INTRODUCTION: Patients with the head and neck squamous cell carcinoma (SCC) are often treated with immune checkpoint inhibitors (ICIs). Recently, antibiotic intake was reported to lower the efficacy of ICIs in patients with several types of cancers. However, it is unclear if antibiotics affect the efficacy of ICIs in patients with head and neck SCC. We retrospectively assessed the influence of antibiotics on the treatment efficacy of nivolumab, an ICI, in patients with head and neck SCC. METHODS: We reviewed the medical records of patients with head and neck SCC treated with nivolumab at the Department of Medical Oncology, Tohoku University Hospital, between 2017 and 2021. Patients who received oral or intravenous antibiotics from a month before the day of nivolumab initiation to the day of the first imaging evaluation of ICI efficacy were assigned to the antibiotic-treated group. The remaining patients were assigned to the antibiotic-untreated group. The response rate (RR), progression-free survival (PFS), and overall survival time (OS) of both groups were compared. RESULTS: Forty-five patients were assigned to the antibiotic-treated group and 19 to the antibiotic-untreated group. The RR, median PFS, and median OS of the antibiotic-treated group were 23.7%, 3.2 months (95% confidential interval [CI]: 2.0-4.1), and 8.4 months (95% CI: 5.3-15.1) and those of the antibiotic-untreated group were 42.1%, 5.8 months (95% CI: 2.3-16.7), and 18.4 months (95% CI: 6.2-23.1), respectively. The PFS of the antibiotic-untreated group was significantly longer than that of the antibiotic-treated group. CONCLUSION: Our findings indicate that antibiotic treatment significantly shortens the PFS with nivolumab therapy in patients with head and neck SCC.

Genome-wide DNA methylation status is a predictor of the efficacy of anti-EGFR antibodies in the second-line treatment of metastatic colorectal cancer: Translational research of the EPIC trial.

PURPOSE: The genome-wide DNA methylation status (GWMS) predicts of therapeutic response to anti-epidermal growth factor receptor (EGFR) antibodies in treating metastatic colorectal cancer. We verified the significance of GWMS as a predictive factor for the efficacy of anti-EGFR antibodies in the second-line treatment of metastatic colorectal cancer. METHODS: Clinical data were obtained from a prospective trial database, and a genome-wide DNA methylation analysis was performed. GWMS was classified into high-methylated colorectal cancer (HMCC) and low-methylated colorectal cancer (LMCC). The patients were divided into subgroups according to the treatment arm (cetuximab plus irinotecan or irinotecan alone) and GWMS, and the clinical outcomes were compared between the subgroups. RESULTS: Of the 112 patients, 58 (51.8%) were in the cetuximab plus irinotecan arm, and 54 (48.2%) were in the irinotecan arm; 47 (42.0%) were in the HMCC, and 65 (58.0%) were in the LMCC group regarding GWMS. Compared with the LMCC group, the progression-free survival (PFS) was significantly shortened in the HMCC group in the cetuximab plus irinotecan arm (median 1.4 vs. 4.1 months, p = 0.001, hazard ratio = 2.56), whereas no significant differences were observed in the irinotecan arm. A multivariate analysis showed that GWMS was an independent predictor of PFS and overall survival (OS) in the cetuximab plus irinotecan arm (p = 0.002, p = 0.005, respectively), whereas GWMS did not contribute to either PFS or OS in the irinotecan arm. CONCLUSIONS: GWMS was a predictive factor for the efficacy of anti-EGFR antibodies in the second-line treatment of metastatic colorectal cancer.

Distinct role of CD8 cells and CD4 cells in antitumor immunity triggered by cell apoptosis using a Herpes simplex virus thymidine kinase/ganciclovir system.

Immune cells can recognize tumor-associated antigens released from dead tumor cells, which elicit immune responses, potentially resulting in tumor regression. Tumor cell death induced by chemotherapy has also been reported to activate immunity. However, various studies have reported drug-induced immunosuppression or suppression of inflammation by apoptotic cells. Thus, this study aimed to investigate whether apoptotic tumor cells trigger antitumor immunity independent of anticancer treatment. Local immune responses were evaluated after direct induction of tumor cell apoptosis using a Herpes simplex virus thymidine kinase/ganciclovir (HSV-tk/GCV) system. The inflammatory response was significantly altered at the tumor site after apoptosis induction. The expression of cytokines and molecules that activate and suppress inflammation simultaneously increased. The HSV-tk/GCV-induced tumor cell apoptosis resulted in tumor growth suppression and promoted T lymphocyte infiltration into tumors. Therefore, the role of T cells after inducing tumor cell death was explored. CD8 T cell depletion abrogated the antitumor efficacy of apoptosis induction, indicating that tumor regression was mainly dependent on CD8 T cells. Furthermore, CD4 T cell depletion inhibited tumor growth, suggesting the potential role of CD4 T cells in suppressive tumor immunity. Tumor tissues were evaluated after tumor cell apoptosis and CD4 T cell depletion to elucidate this immunological mechanism. Foxp3 and CTLA4, regulatory T-cell markers, decreased. Furthermore, arginase 1, an immune-suppressive mediator induced by myeloid cells, was significantly downregulated. These findings indicate that tumors accelerate CD8 T cell-dependent antitumor immunity and CD4 T cell-mediated suppressive immunity. These findings could be a therapeutic target for immunotherapy in combination with cytotoxic chemotherapy.

Comparison of efficacy and safety between carboplatin-etoposide and cisplatin-etoposide combination therapy in patients with advanced neuroendocrine carcinoma, retrospective study.

INTRODUCTION: Neuroendocrine carcinoma (NEC) is characterized by a poor prognosis and is generally treated with platinum and etoposide combination therapy as first-line chemotherapy. However, it remains uncertain whether carboplatin and etoposide combination therapy (CE) and cisplatin and etoposide combination therapy (PE) have comparable treatment efficacy. In this retrospective analysis, we compared the efficacy and safety of CE and PE in patients with NEC. METHODS: We retrospectively reviewed the patient's clinical record from 2005 to 2022 at the Department of Medical Oncology, Tohoku University Hospital. Patients who received either CE or PE were included in the study. Statistical analyses were performed using JMP Pro 16.0 (SAS Institute Inc., Cary, N.C., USA). RESULTS: A total of 104 patients were enrolled, with 73 patients assigned to the CE group and 31 patients assigned to the PE group. Statistically, the response rate, progression-free survival (PFS) time and overall survival (OS) time were 42.6%, 5.1 months (95%CI: 3.5-6.3) and 13.6 months (95%CI: 8.9-17.4), respectively, in the CE groups and 44.4%, 5.6 months (95%CI: 3.1-7.0) and 12.5 months (95%CI: 11.2-14.6), respectively, in the PE groups. There was no significant difference in treatment efficacy between the CE and the PE groups. However, the number of patients with elevated creatinine (3.35 mg/dl and 3.88 mg/dl in two patients, respectively) was significantly higher in the PE group than in the CE group. CONCLUSION: The efficacy of CE and PE in patients with NEC is comparable. However, the incidence of renal dysfunction was found to be significantly higher in the PE group than in the CE group.

Periostin splice variants affect craniofacial growth by influencing chondrocyte hypertrophy.

INTRODUCTION: Periostin, an extracellular matrix protein, plays an important role in osteogenesis and is also known to activate several signals that contribute to chondrogenesis. The absence of periostin in periostin knockout mice leads to several disorders such as craniosynostosis and periostitis. There are several splice variants with different roles in heart disease and myocardial infarction. However, little is known about each variant's role in chondrogenesis, followed by bone formation. Therefore, the aim of this study is to investigate the role of several variants in chondrogenesis differentiation and bone formation in the craniofacial region. Periostin splice variants included a full-length variant (Control), a variant lacking exon 17 (ΔEx17), a variant lacking exon 21 (ΔEx21), and another variant lacking both exon 17 and 21 ***(ΔEx17&21). MATERIALS AND METHODS: We used C56BL6/N mice (n = 6) for the wild type (Control)*** and the three variant type mice (n = 6 each) to identify the effect of each variant morphologically and histologically. Micro-computed tomography demonstrated a smaller craniofacial skeleton in ΔEx17s, ΔEx21s, and ΔEx17&21s compared to Controls, especially the mandibular bone. We, thus, focused on the mandibular condyle. RESULTS: The most distinctive histological observation was that each defected mouse appeared to have more hypertrophic chondrocytes than Controls. Real-time PCR demonstrated the differences among the group. Moreover, the lack of exon 17 or exon 21 in periostin leads to inadequate chondrocyte differentiation and presents in a diminutive craniofacial skeleton. DISCUSSION: Therefore, these findings suggested that each variant has a significant role in chondrocyte hypertrophy, leading to suppression of bone formation.

Successful treatment of metastatic fibrosarcomatous dermatofibrosarcoma protuberans with imatinib mesylate.

Dermatofibrosarcoma protuberans (DFSP) is a fibrohistiocytic tumor characterized by a high risk of local recurrence but a low risk of metastasis. A small subpopulation of DFSP undergoes fibrosarcomatous (FS) change, and approximately 15%-57% of cases of DFSP with FS change metastasizes, leading to a poor prognosis. In this report, a case of metastatic FS-DFSP that was successfully treated with imatinib mesylate in which the IHC staining pattern of recurrent DFSP was quantitatively analyzed in primary and metastatic DFSP areas, is described. Importantly, the recurrent area was composed of two IHC staining patterns (CD34low PD-L1high Ki67high , and CD34high PD-L1low Ki67low pattern), while the metastatic area showed a clonal pattern (CD34high PD-L1low Ki67intermediate ) in the present case. In this report, we described a case of metastatic fibrosarcomatous DFSP successfully treated with imatinib mesylate. This case suggests a subpopulation of DFSP with a favorable metastatic pattern.

Contribution of Fcγ receptor IIB to creating a suppressive tumor microenvironment in a mouse model.

Various immune cells are recruited in the tumor microenvironment. It is well established that cellular immune responses, such as cytotoxic or suppressive activities, play an important role in regulating tumor growth and metastasis. However, the contribution of humoral immune responses against tumors is poorly understood. Fc receptors constitute critical elements for the up- or downregulation of immune responses through immune complexes. Here, we examined the potential role of the inhibitory Fc receptor, Fcγ receptor IIB (FcγRIIB), in tumor immunity using a mouse model. Our findings indicated that tumor-specific antibodies are induced in tumor-bearing mice and control tumor immunity. FcγRIIB deletion significantly improved both cellular and humoral immunity against tumors and delayed tumor growth. These findings indicated that spontaneous antibodies against tumors create a suppressive tumor microenvironment through FcγRIIB signaling, thus suggesting an attractive therapeutic target for cancer immunotherapy.

Retrospective analysis on the clinical outcomes of recombinant human soluble thrombomodulin for disseminated intravascular coagulation syndrome associated with solid tumors.

BACKGROUND: Recombinant human soluble thrombomodulin (rTM) has been established and introduced in the clinic as a standard treatment for disseminated intravascular coagulation (DIC). However, the efficacy and safety of rTM for DIC associated with solid tumors (DIC-STs) have not been fully established. Here, we performed a retrospective analysis of the clinical outcomes of rTM for DIC-STs and considered a treatment strategy with rTM for DIC-STs. METHODS: Patients with DIC-STs between November 2009 and March 2016 in 2 cancer core hospitals were retrospectively analyzed. Data, including patient background, treatment course, and clinical outcomes of rTM for DIC-STs, were extracted. The clinical outcomes were evaluated by comparing the DIC score, resolution rate, and overall survival (OS) duration. RESULTS: The study included 123 patients with DIC-STs. The median OS in all patients was 41 days. The DIC resolution rate was 35.2%. DIC scores and DIC-related blood test data (fibrin degradation product and prothrombin time-international normalized ratio) significantly improved at the end of rTM administration (P < 0.001). The OS duration was longer in patients who were treated with chemotherapy after DIC onset than in those who were not treated with chemotherapy (median, 178 days vs. 17 days, P < 0.001). In both univariate and multivariate analyses, chemotherapy after DIC onset showed the strongest association with OS. CONCLUSIONS: rTM can at least temporarily improve or maintain the state of DIC-STs. It is suggested that prolongation of survival can be expected when control of DIC and treatment of the underlying disease are compatible.

Involvement of CX3CL1 in the Migration of Osteoclast Precursors Across Osteoblast Layer Stimulated by Interleukin-1ß.

The trigger for bone remodeling is bone resorption by osteoclasts. Osteoclast differentiation only occurs on the old bone, which needs to be repaired under physiological conditions. However, uncontrolled bone resorption is often observed in pro-inflammatory bone diseases, such as rheumatoid arthritis. Mature osteoclasts are multinuclear cells that differentiate from monocyte/macrophage lineage cells by cell fusion. Although Osteoclast precursors should migrate across osteoblast layer to reach bone matrix before maturation, the underlying mechanisms have not yet been elucidated in detail. We herein found that osteoclast precursors utilize two routes to migrate across osteoblast layer by confocal- and electro-microscopic observations. The osteoclast supporting activity of osteoblasts inversely correlated with osteoblast density and was positively related to the number of osteoclast precursors under the osteoblast layer. Osteoclast differentiation was induced by IL-1ß, but not by PGE2 in high-density osteoblasts. Osteoblasts and osteoclast precursors expressed CX3CL1 and CX3CR1, respectively, and the expression of CX3CL1 increased in response to interleukin-1ß. An anti-CX3CL1-neutralizing antibody inhibited the migration of osteoclast precursors and osteoclast differentiation. These results strongly suggest the involvement of CX3CL1 in the migration of osteoclast precursors and osteoclastogenesis, and will contribute to the development of new therapies for bone diseases. J. Cell. Physiol. 232: 1739-1745, 2017. © 2016 Wiley Periodicals, Inc.

IL-4 blockade alters the tumor microenvironment and augments the response to cancer immunotherapy in a mouse model.

Recent findings show that immune cells constitute a large fraction of the tumor microenvironment and that they modulate tumor progression. Clinical data indicate that chronic inflammation is present at tumor sites and that IL-4, in particular, is upregulated. Thus, we tested whether IL-4 neutralization would affect tumor immunity. Current results demonstrate that the administration of a neutralizing antibody against IL-4 enhances anti-tumor immunity and delays tumor progression. IL-4 blockade also alters inflammation in the tumor microenvironment, reducing the generation of both immunosuppressive M2 macrophages and myeloid-derived suppressor cells, and enhancing tumor-specific cytotoxic T lymphocytes. In addition, IL-4 blockade improves the response to anti-OX40 Ab or CpG oligodeoxynucleotide immunotherapies. These findings suggest that IL-4 affects anti-tumor immunity and constitutes an attractive therapeutic target to reduce immune suppression in the tumor microenvironment, thus enhancing the efficacy of cancer therapy.

Efficacy and Safety Assessment of Paclitaxel in Patients with Docetaxel-Resistant Esophageal Squamous Cell Carcinoma.

BACKGROUND: Incomplete cross-resistances between paclitaxel (PTX) and docetaxel (DTX) has been demonstrated in several types of cancer. The objective of the present study was to assess the existence of cross-resistance between PTX and DTX in esophageal squamous cell carcinoma. METHODS: Patients in the PTX group received PTX without DTX pretreatment, patients in the prior DTX (Pr-DTX) group received PTX after the development of resistance to DTX, and patients in the DTX group received DTX without subsequent PTX treatment. RESULTS: A total of 73 patients were enrolled. The response rates to PTX in the PTX and Pr-DTX groups were 22.7 and 20.0%, respectively. The median progression-free survival times from the first day of PTX treatment in the PTX and Pr-DTX groups were 113 (95% CI 56-154) and 97 days (95% CI 36-189), respectively. The median overall survival times from the first day of DTX treatment in the Pr-DTX and DTX groups were 315 (95% CI 124-453) and 148 days (95% CI 139-177), respectively. CONCLUSIONS: There is no or incomplete clinical cross-resistance between PTX and DTX in esophageal squamous cell carcinoma. Replacement of DTX with PTX is a suitable treatment option for patients with DTX-resistant esophageal squamous cell carcinoma.

Nivolumab-induced Thrombotic Thrombocytopenic Purpura in Patients with Gastric Tube Cancer.

Recently, immune checkpoint inhibitors (ICIs) have been used to treat several cancer types. ICIs have been reported to cause a wide variety of immune-related adverse events, including endocrine, neurologic, gastrointestinal, and cutaneous disorders. Thrombotic thrombocytopenic purpura (TTP) is an autoimmune hematologic disorder characterized by the presence of autoantibodies against a disintegrin and metalloprotease with thrombospondin-1, member 13. Several previous cases of TTP were thought to have been caused by ICI treatment. We herein report a rare case of TTP that developed after long-term treatment with an ICI (nivolumab) for gastric tube cancer.

Chylous Ascites Associated with Advanced Pancreatic Cancer That Improved with Appropriate Treatment: A Case Report.

Chylous ascites is a rare form of ascites with high triglyceride content arising from the thoracoabdominal lymph nodes in the peritoneal cavity due to various benign or malignant etiologies, including pancreatic cancer. During cancer chemotherapy, the accumulation of ascites can lead to the deterioration of the patient's general condition, making chemotherapy administration difficult, and resulting in a poor prognosis. We encountered a rare case of chylous ascites complicated by advanced pancreatic cancer. The patient presented with a discrepancy between the shrinkage of the pancreatic cancer and the accumulation of ascites. Therefore, we were able to promptly diagnose chylous ascites by performing biochemical tests. The patient was treated with octreotide, reportedly effective in treating chylous ascites, which rapidly improved the chylous ascites and general condition of the patient, allowing the patient to continue chemotherapy for pancreatic cancer. Therefore, physicians should consider the possibility of chylous ascites when clinically unexplained ascites are observed in patients with advanced cancer. The investigation and treatment of chylous ascites should be initiated as soon as possible.

Correlation between Efficacy and Cardiovascular Adverse Events in Patients with Advanced Solid Cancer Who Received VEGF Pathway Inhibitors: Hypertension within the First Eight Weeks is Associated with Favorable Outcomes of Patients Treated with VEGF Pathway Inhibitors.

Objective Many vascular endothelial growth factor (VEGF) pathway inhibitors are used in the treatment of patients with various advanced cancers; however, treatments induce cardiovascular adverse events (CVAEs), such as hypertension, heart failure, arrhythmia, arterial or venous embolism, and hemorrhage. Some studies have suggested a correlation between efficacy and CVAEs; however, further evidence is required. This study evaluated real-world data concerning the frequency and degree of CVAEs and possible associations between CVAEs and efficacy in such patients. Methods and Patients We analyzed CVAEs observed in 294 patients with advanced cancer who were treated with ramucirumab, regorafenib, pazopanib, sunitinib, or sorafenib. Results CVAEs of any grade and proteinuria within 8 weeks after the initiation of VEGF pathway inhibitors (early) or during the treatment period (total period) were observed in 72%-85% and 77%-92% of the patients, respectively. The progression-free survival (PFS) of patients with a CVAE of grade ≥1 in the early period was favorable compared with the PFS of those who had no CVAE (median, 4.9 vs. 3.5 months, P = 0.016, log-rank test). Furthermore, the PFS of patients with a CVAE grade ≥3 in the early period was favorable compared to that of those with CVAEs of grades 0-2. Taken together, a higher degree of CVAE was correlated with favorable patient outcomes. Conclusion This study revealed the frequency and degree of CVAEs in patients with solid cancers who received VEGF pathway inhibitors in a real-world setting and added evidence regarding the correlation between CVAEs and efficacy of VEGF pathway inhibitors.

Fatal case of Capnocytophaga sepsis from a dog bite in a patient with splenic hypoplasia.

Background: Capnocytophaga canimorsus is an oral commensal bacteria in dogs and may cause severe infection following a dog bite. This is a case of fatal C. canimorsus sepsis with acute infectious purpura fulminans (AIPF) in a healthy patient with splenic hypoplasia. Case Presentation: A healthy 49-year-old man was admitted to the intensive care unit (ICU) for septic shock and AIPF 4 days after a dog bite to his mouth. Computed tomography revealed a small spleen measuring 53 cm3 but no other source of infection. Despite intensive care, the patient died of multiple organ failure and progressive shock on the fifth ICU day. Polymerase chain reaction of blood samples identified the C. canimorsus gene on a later day. Conclusion: Capnocytophaga canimorsus from dog bites may cause fatal AIPF. Splenic hypoplasia and bite wounds in well-perfused areas such as the oral cavity are possible risk factors for sepsis. All dog bites should warrant medical attention.

Depth of response may predict clinical outcome in patients with recurrent/metastatic head and neck cancer treated with pembrolizumab-containing regimens.

Background: Pembrolizumab-containing regimens are standards of care for recurrent and metastatic head and neck squamous cell carcinoma (R/M HNSCC). The depth of response (DpR) predicts the survival of patients with several types of solid cancers; however, its association with the survival outcomes of patients with R/M HNSCC treated with pembrolizumab-containing regimens remains unclear. Methods: This study included 66 patients with R/M HNSCC who received a pemblolizumab-containing regimen as a first-line therapy at Tohoku University Hospital, Sendai, Japan. The patients' characteristics, combined positive score, baseline tumor size, tumor response, DpR, overall survival (OS), progression-free survival (PFS), PFS2, and adverse events were reviewed. The associations between DpR and survival outcomes were analyzed. Results: The 1 year-OS and 1 year-PFS rates of pembrolizumab-containing regimens were 69.4% and 24.4%, respectively. The response rate was 28.8%. The mean and median values of tumor change from baseline were 5.1% and -9.0%. In the correlation analysis, a significant negative correlation was observed between tumor change rate from baseline and survival outcomes (OS: r= -0.41, p=0.0017; PFS: r=-0.49, p<0.001). In the multivariate analysis, DpR with tumor change of ≤-45 was associated with better OS and PFS. Conclusion: DpR induced by pembrolizumab-containing regimens may be a predictive factor for OS and PFS in patients with R/M HNSCC.

FOLFIRI Chemotherapy for Patients With Metastatic Urachal Carcinoma.

BACKGROUND/AIM: Urachal carcinoma is a rare cancer, with limited evidence regarding systemic chemotherapy for metastatic urachal carcinoma. This study aimed to evaluate the efficacy and safety of a combination therapy of 5-fluorouracil and irinotecan (FOLFIRI) in patients with metastatic urachal carcinoma. PATIENTS AND METHODS: Patients with metastatic urachal carcinoma treated with FOLFIRI between March 2008 and April 2023 at the Department of Medical Oncology, Tohoku University Hospital, were retrospectively analyzed using medical records. RESULTS: Six patients with urachal carcinoma received FOLFIRI. The histological type was adenocarcinoma in all patients. The metastatic or recurrent sites were the peritoneum, lungs, lymph nodes, and local relapse sites. Three patients received FOLFIRI as first-line chemotherapy, and the other three received FOLFIRI as second-line chemotherapy. Two patients had only non-measurable lesions as the targets of tumor response. The best response was the stable disease or non-complete response/non-progressive disease in four patients, with a disease control rate of 67%. The median progression-free survival was 7.5 months. In two patients with ascites only as the site of metastasis, the amount of ascites and serum tumor marker levels decreased after FOLFIRI was initiated. Grade 3/4 toxicities included grade 3 neutropenia in one patient and grade 3 diarrhea in one patient. CONCLUSION: FOLFIRI has modest efficacy and good tolerability for the treatment of metastatic urachal carcinoma.

BRAF and MEK Inhibitor Treatment for Metastatic Undifferentiated Sarcoma of the Spermatic Cord with BRAF V600E Mutation.

An 18-year-old Japanese man was diagnosed with an undifferentiated sarcoma of the spermatic cord, with multiple distant metastases to the lungs and bones. The patient received doxorubicin-based standard chemotherapy. Although the chemotherapy was effective, it induced severe adverse events, which led to treatment discontinuation. A comprehensive genomic profiling test using resected tumor tissue revealed the BRAF V600E mutation. Based on the result, the patient received combination therapy with dabrafenib and trametinib. The combination therapy achieved a good response with few adverse events. However, 6.5 months later, pleural metastases and meningeal dissemination had emerged. A liquid comprehensive genomic profiling test was performed after the progression to identify the resistance mechanism, which resulted in the detection of no actionable gene alterations other than BRAF V600E. This report shows that the BRAF V600E mutation may be a promising therapeutic target and that resistance to the targeted therapy could also occur in soft tissue sarcoma. The significance of BRAF mutations across different types of cancer should be validated, and it is necessary to apply targeted therapies and develop methods to overcome resistance based on the optimal use of comprehensive genomic profiling tests.