Phase II Trial of Nivolumab in Metastatic Rare Cancer with dMMR or MSI-H and Relation with Immune Phenotypic Analysis (the ROCK Trial)

PURPOSE

Mismatch repair deficiency (dMMR)/microsatellite instability-high (MSI-H) are positive predictive markers for immune checkpoint inhibitors. However, data on the activity of nivolumab in advanced dMMR/MSI-H rare cancers and more accurate biomarkers are worth exploring.

PATIENTS AND METHODS

We conducted a multicenter phase II, open-label, single-arm clinical trial to explore the effectiveness and safety of nivolumab monotherapy in patients with advanced rare cancers with dMMR/MSI-H, in parallel with immune phenotype analysis, to explore new biomarkers. A Bayesian adaptive design was applied. Characterization of peripheral blood mononuclear cells (PBMC) was characterized by multicolor flow cytometric analysis and CyTOF using samples collected before and after the intervention. The dMMR was identified by the complete loss of MLH1/MSH2/MSH6/PMS2.

RESULTS

From May 2018 to March 2021, 242 patients were screened, and 11 patients were enrolled, of whom 10 were included in the full analysis. Median follow-up was 24.7 months (interquartile range, 12.4-31.5). Objective response rate was 60% [95% confidence interval (CI), 26.2-87.8] by central assessment and 70% (95% CI, 34.8-93.3) by local investigators. Median progression-free survival was 10.1 months (95% CI, 0.9-11.1). No treatment-related adverse events of grade 3 or higher were observed. Patients with a tumor mutation burden of ≥10/Mb showed a 100% response rate (95% CI, 47.8-100). Responders had increased T-bet+ PD-1+ CD4+ T cells in PBMC compared with nonresponders (P < 0.05).

CONCLUSIONS

The trial met its primary endpoint with nivolumab, demonstrating clinical benefit in advanced dMMR/MSI-H rare solid cancers. Besides, the proportion of T-bet+ PD-1+ CD4+ T-cells may serve as a novel predictive biomarker.

Preferential B cell differentiation by combined immune checkpoint blockade for renal cell carcinoma is associated with clinical response and autoimmune reactions

Combined immune checkpoint blockade (ICB) is effective therapy for renal cell carcinoma (RCC). However, the dynamic changes in circulating B cells induced by combined ICB have not been clarified. The present study prospectively examined 22 patients scheduled to receive ICB for unresectable or metastatic RCC between March 2018 and August 2021. Eleven patients received combined therapy with anti-PD-1 (nivolumab) and anti-CTLA-4 (ipilimumab), and the other 11 patients received nivolumab monotherapy. Comprehensive phenotypes of circulating immune cells obtained prior to and after ICB therapy were analyzed by flow cytometry. Although the proportion of naïve B cells among total B cells was significantly decreased, that of switched memory B cells was significantly increased after combined therapy. In responders, the proportion of B cells among peripheral blood mononuclear cells was significantly higher prior to ICB therapy, and the proportion of switched memory B cells among total B cells tended to increase after ICB therapy. Of note, the proportion of plasmablasts among total B cells was significantly increased after ICB therapy in patients who developed severe immune-related adverse events (irAEs), and the proportion of B cells among peripheral blood decreased significantly. Furthermore, in four of five patients who developed immune-related hypophysitis following combined therapy, anti-pituitary antibody was detected in the serum. These results suggested that immune-related hypophysitis was closely related to the increase in circulating plasmablasts. Collectively, this study suggests that combined ICB promotes the differentiation of B cell populations, which is associated with efficient tumor suppression and development of irAEs.

Survival outcomes including salvage therapy of adult head and neck para-meningeal rhabdomyosarcoma: a multicenter retrospective study from Japan

BACKGROUND

Rhabdomyosarcoma is the most common soft tissue sarcoma in children, but rare in adults. Para-meningeal rhabdomyosarcoma in head and neck (PM-HNRMS) is less applicable for surgery due to the anatomic reason. PM-HNRMS has a poor prognosis in children. However, its clinical outcomes remain unclear in adults due to the rarity. Further, there is almost no detailed data about salvage therapy.

METHODS

We retrospectively examined the adult patients with PM-HNRMS treated at institutions belonging to the Kyushu Medical Oncology Group from 2009 to 2022. We evaluated the overall survival (OS) and progression-free survival (PFS) of the patients who received a first-line therapy. We also reviewed the clinical outcomes of patients who progressed against a first-line therapy and received salvage therapy.

RESULTS

Total 11 patients of PM-HNRMS received a first-line therapy. The characteristics were as follows: median age: 38 years (range 25 - 63 years), histology (alveolar/spindle): 10/1, and risk group (intermediate/high): 7/4. As a first-line therapy, VAC and ARST0431-based regimen was performed in 10 and 1 patients, respectively. During a first-line therapy, definitive radiation for all lesions were performed in seven patients. The median PFS was 14.2 months (95%CI: 6.0 - 25.8 months): 17.1 months (95%CI: 6.0 - not reached (NR)) for patients with stage I-III and 8.5 months (95%CI: 5.2 - 25.8 months) for patients with stage IV. The 1-year and 3-year PFS rates were 54.5% and 11.3% for all patients. Median OS in all patients was 40.8 months (95%CI: 12.1 months-NR): 40.8 months (95%CI: 12.1 - NR) for patients with stage I-III and NR for patients with stage IV. The 5-year OS rate was 48.5% for all patients. Among seven patients who received salvage therapy, three are still alive, two of whom remain disease-free for over 4 years after completion of the last therapy. Those two patients received multi-modal therapy including local therapy for all detected lesions.

CONCLUSION

The cure rate of adult PM-HNRMS is low in spite of a first-line therapy in this study. Salvage therapy might prolong the survival in patients who received the multi-modal therapy including local therapy for all detected lesions.

Case Report: Resolution of remitting seronegative symmetrical synovitis with pitting edema during nivolumab therapy for gastric cancer

The anti-programmed cell death-1 (PD-1) antibody nivolumab has been shown to significantly prolong the survival of patients with unresectable advanced or recurrent gastric cancer (AGC). However, immune-related adverse events (irAEs), which show different profiles from those of cytotoxic agents or conventional molecular-targeted drugs including tyrosine kinase inhibitors, have been reported. Remitting seronegative symmetrical synovitis with pitting edema (RS3PE) is a rare autoimmune disorder with acute-onset, rheumatoid factor-negative, symmetric synovitis associated with limb edema observed in elderly persons. A case of RS3PE syndrome that developed after administration of nivolumab for advanced gastric cancer is reported. This is the first report of a case of RS3PE syndrome as an irAE caused by nivolumab in a patient with gastric cancer.

RHAMM marks proliferative subpopulation of human colorectal cancer stem cells

The cancer stem cell (CSC) theory features typically rare self-renewing subpopulation that reconstitute the heterogeneous tumor. Identification of molecules which characterize the feature of CSCs is a key imperative for further understanding of tumor heterogeneity and for the development of novel therapeutic strategies. However, the use of conventional markers of CSCs is still insufficient for the isolation of bona fide CSCs. We investigated organoids which are miniature forms of tumor tissues with reconstructing cellular diversity to identify specific marker to characterize CSCs in heterogeneous tumors. Here, we report that receptor for hyaluronan-mediated motility (RHAMM) expresses in a subpopulation of CD44+ conventional human colorectal CSC fraction. Single-cell transcriptomics of organoids highlighted RHAMM positive proliferative cells that revealed distinct characteristics among the various cell types. Prospectively isolated RHAMM+ CD44+ cells from the human colorectal cancer tissues showed highly proliferative character with self-renewal ability in comparison with the other cancer cells. Furthermore, inhibition of RHAMM strongly suppressed organoids formation in vitro and inhibited the tumor growth in vivo. Our findings suggest that RHAMM is a potential therapeutic target because it is a specific marker of the proliferative subpopulation within the conventional CSC fraction.

Inhibition of insulin-like growth factor-1 receptor enhances eribulin-induced DNA damage in colorectal cancer

Microtubule targeting agents (MTAs) such as taxanes are broadly used for the treatment of patients with cancer. Although MTAs are not effective for treatment of colorectal cancer (CRC), preclinical studies suggest that a subset of patients with CRC, especially those with cancers harboring the BRAF mutation, could benefit from such agents. However, two MTAs, eribulin (Eri) and vinorelbine, have shown limited clinical efficacy. Here, we report that insulin-like growth factor 1 receptor (IGF-1R) signaling is involved in Eri resistance. Using CRC cell lines, we showed that Eri induces activation and subsequent translocation of IGF-1R to the nucleus. When the activation and/or nuclear translocation of IGF-1R was inhibited, Eri induced DNA damage and enhanced G₂ /M arrest. In a xenograft model using the Eri-resistant SW480 cell line, the combination of Eri and the IGF-1R inhibitor linsitinib suppressed tumor growth more efficiently than either single agent. Thus, our results indicated that combination dosing with Eri and an IGF-1R inhibitor could overcome Eri resistance and offer a therapeutic opportunity in CRC.

Potential therapeutic targets discovery by transcriptome analysis of an in vitro human gastric signet ring carcinoma model

BACKGROUND

Loss of E-cadherin expression is frequently observed in signet ring carcinoma (SRCC). People with germline mutations in CDH1, which encodes E-cadherin, develop diffuse gastric cancer at a higher rate. Loss of E-cadherin expression is thus assumed to trigger oncogenic development.

METHODS

To investigate novel therapeutic targets for gastric SRCC, we engineered an E-cadherin-deficient SRCC model in vitro using a human gastric organoid (hGO) with CDH1 knockout (KO).

RESULTS

CDH1 KO hGO cells demonstrated distinctive morphological changes similar to SRCC and high cell motility. RNA-sequencing revealed up-regulation of matrix metalloproteinase (MMP) genes in CDH1 KO hGO cells compared to wild type. MMP inhibitors suppressed cell motility of CDH1 KO hGO cells and SRCC cell lines in vitro. Immunofluorescent analysis with 95 clinical gastric cancer tissues revealed that MMP-3 was specifically abundant in E-cadherin-aberrant SRCC. In addition, CXCR4 molecules translocated onto the cell membrane after CDH1 KO. Addition of CXCL12, a ligand of CXCR4, to the culture medium prolonged cell survival of CDH1 KO hGO cells and was abolished by the inhibitor, AMD3100. In clinical SRCC samples, CXCL12-secreting fibroblasts showed marked infiltration into the cancer area.

CONCLUSIONS

E-cadherin deficient SRCCs might gain cell motility through upregulation of MMPs. CXCL12-positive cancer-associated fibroblasts could serve to maintain cancer-cell survival as a niche. MMPs and the CXCL12/CXCR4 axis represent promising candidates as novel therapeutic targets for E-cadherin-deficient SRCC.

IMPROVE bleeding score predicts major bleeding in advanced gastrointestinal cancer patients with venous thromboembolism

BACKGROUND

The incidence of venous thromboembolism has been reported as 20% in cancer patients. Anticoagulation therapy is the standard treatment for venous thromboembolism. On the other hand, bleeding should be carefully managed, because advanced cancer, particularly gastrointestinal cancer, carries a high risk of bleeding. However, the optimal management for cancer-associated thromboembolism remains to be clarified.

METHODS

We retrospectively examined patients with advanced gastrointestinal cancer, including gastric cancer and colorectal cancer, who were treated with chemotherapy between 2014 and 2018 for the incidence and characteristics of venous thromboembolism and bleeding.

RESULTS

In total, 194 patients (120 men, 74 women) were enrolled in this study. The underlying pathology was gastric cancer in 74 cases and colorectal cancer in 120 cases. Of the 194 patients, 40 patients (20.6%) were diagnosed with venous thromboembolism and 10 patients (5.2%) were diagnosed with concomitant pulmonary thromboembolism. Conversely, bleeding was observed in 29 patients (15%). The location of bleeding was the primary tumor in 17 cases, metastatic tumor in 9 and hemorrhagic gastric ulcer in 3. Within the venous thromboembolism group (n = 40), bleeding was observed in 10 patients (25%). Multivariate analysis showed that International Medical Prevention Registry on Venous Thromboembolism (IMPROVE) bleeding score ≥7 correlated significantly with major bleeding (P = 0.01). In patients with a low risk of bleeding, major bleeding was observed in only three patients.

CONCLUSIONS

IMPROVE bleeding score may predict the risk for bleeding in gastrointestinal cancer patients with venous thromboembolism. Selecting patients with a low risk of bleeding using with IMPROVE bleeding score is expected to contribute to the safer management of anticoagulation therapy for cancer-associated thromboembolism.

Macrophages are primed to transdifferentiate into fibroblasts in malignant ascites and pleural effusions

Cancer-associated fibroblasts (CAFs) play an important role in cancer progression. However, the origin of CAFs remains unclear. This study shows that macrophages in malignant ascites and pleural effusions (cavity fluid-associated macrophages: CAMs) transdifferentiate into fibroblast-like cells. CAMs obtained from gastrointestinal cancer patients were sorted by flow cytometry and cultured in vitro. CD45⁺CD14⁺ CAMs transdifferentiated into CD45^-CD90⁺ fibroblast-like cells that exhibited spindle shapes. Then, cDNA microarray analysis showed that the CD45^-CD90⁺ fibroblast-like cells (macrophage-derived CAFs: MDCAFs) had a fibroblast-specific gene expression signature and produced growth factors for epithelial cell proliferation. Human colon cancer cells transplanted into immunodeficient mice with MDCAFs formed larger tumors than cancer cells alone. Gene ontology analyses showed the involvement of TGFβ signaling and cell-matrix adhesion in MDCAFs, and transdifferentiation of CAMs into MDCAFs was canceled by inhibiting TGFβ and cell adhesion. Furthermore, the acquired genetic alterations in hematopoietic stem cells (HSCs) were shared in CAMs and MDCAFs. Taken together, CAMs could be a source of CAFs and might originate from HSCs. We propose the transdifferentiation process of CAMs into MDCAFs as a new therapeutic target for fibrosis associated with gastrointestinal cancer.

Spontaneous Regression of Metachronous Intra-Abdominal Desmoid Tumor in a Patient with Familial Adenomatous Polyposis

Desmoid tumors are clonal fibroblastic neoplasms that arise in soft tissues. Patients with familial adenomatous polyposis (FAP) can develop intra-abdominal desmoid tumors. However, metachronous appearance of intra-abdominal desmoid tumor is rare, and its clinical course is not well known. Here, we report a case of spontaneous regression of metachronous intra-abdominal desmoid tumor in a 36-year-old man with FAP. The patient was diagnosed with FAP and underwent laparoscopic total colorectomy. Intra-abdominal desmoid tumor appeared 2 years later and progressed despite treatment with tamoxifen and sulindac. He received four cycles of combinatory therapy with dacarbazine and adriamycin, resulting in shrinkage and stabilization of the desmoid tumor even after cessation of chemotherapy. A new intra-abdominal desmoid tumor developed 2 years later at a different site from the first lesion and progressed from 65 mm to 70 mm in diameter within a month. The size of the first lesion, however, remained unchanged. We prepared for chemotherapy because the second lesion progressed, but follow-up computed tomography showed spontaneous shrinkage of the second lesion. The patient still has not needed additional therapy as of more than 4 years after the appearance of the second lesion. Immunohistochemical staining showed the presence of macrophages in the second lesion. Although metachronous intra-abdominal desmoid tumor is rare and management protocols have yet to be established, this case suggests that an active surveillance approach may be applicable under careful follow-up in asymptomatic patients.

Does the Use of Peripheral Immune-Related Markers Indicate Whether to Administer Pazopanib, Trabectedin, or Eribulin to Advanced Soft Tissue Sarcoma Patients?

Pazopanib, trabectedin, and eribulin are administered for the treatment of soft tissue sarcomas (STSs); however, there is little consensus on which agent should be preferentially used in a clinical setting. This study assessed whether peripheral immune-related markers served as a useful reference when selecting pazopanib, trabectedin, or eribulin. This study included 63 patients who were administered pazopanib, trabectedin, or eribulin for advanced STSs between March 2015 and December 2020. Patients were divided into three groups based on the first drug administered among these three drugs. Differences in overall survival (OS) or progression-free survival (PFS) among the three groups were analyzed. OS showed no significant differences among the drugs administered first. For patients with low neutrophil-to-lymphocyte ratio (NLR), the OS of patients administered pazopanib as the first choice was shorter than the others (hazard ratio [HR] = 9.53, 95% confidence interval [CI] = 1.94–18.13, p = 0.0018). In the low platelet-to-lymphocyte ratio (PLR) subgroup, the OS of the patients administered eribulin for the first choice was longer than that of the others (HR = 0.32, 95%CI = 0.10–0.98, p = 0.046). Therefore, NLR and PLR might be used as prognostic indicators to dictate whether STS patients receive pazopanib, trabectedin, or eribulin.

Improvement in recurring nivolumab-induced pneumonitis with repetitive administration of infliximab in a patient with head and neck cancer: A case report

Severe pneumonitis induced by nivolumab, an anti-programmed cell death-1 monoclonal antibody, is a rare but potentially fatal immune-related adverse event. In cases of steroid-refractory pneumonitis, an appropriate therapeutic strategy using anti-tumor necrosis factor-α (TNF-α) antibody has not been established. A 59-year-old female was diagnosed with hypopharyngeal squamous cell carcinoma. Previous therapies including chemoradiotherapy and throat laryngectomy were performed, but metastatic recurrence appeared in the intrapulmonary and mediastinal lymph nodes. The patient was administered nivolumab. On the 14th day of nivolumab administration, the patient experienced dyspnea and computed tomography of the chest showed multiple consolidations in the right lung. She was diagnosed with nivolumab-induced pneumonitis. Because the pneumonitis was refractory to steroid therapy, she was administered infliximab, and the pneumonitis improved. On the 72nd and 101st days of nivolumab administration, nivolumab-induced pneumonitis re-appeared with an elevated serum TNF-α concentration. In each occurrence of pneumonitis, repetitive administration of infliximab improved the pneumonitis. Repetitive administration of infliximab may be effective for treating recurrent nivolumab-induced pneumonitis that is associated with an increased serum TNF-α concentration.

Prominent PD-L1-positive M2 macrophage infiltration in gastric cancer with hyper-progression after anti-PD-1 therapy: A case report

RATIONALE

Anti-PD-1 antibody is the standard therapy for treatment-resistant gastric cancer, but only a limited number of patients respond. Additionally, cases of hyper-progressive disease (HPD) in which tumor growth accelerates after anti-PD-1 antibody administration have been reported; however, the biological mechanism has not been elucidated.

PATIENT CONCERNS

In the present case, metastatic gastric cancer was treated with the anti-PD-1 antibody, nivolumab, as third-line treatment.

DIAGNOSIS

After the initiation of nivolumab therapy, a rapidly enlarging para-aortic lymph nodes were observed leading to the diagnosis of HPD.

INTERVENTIONS

Multiplex immunohistochemistry was used to examine immune cells infiltrating in the primary tumor and in liver metastasis which were obtained before nivolumab treatment, and in lymph node metastasis which presented with HPD after nivolumab therapy.

OUTCOMES

In the primary tumor, helper T (Th) cells, cytotoxic T lymphocytes (CTLs), regulatory T (Treg) cells, and PD-L1-negative macrophages were observed. On the other hand, in metastatic lymph nodes presenting with HPD, PD-L1-positive macrophages prominently increased, while Treg cells, CTLs, and Th cells decreased. PD-L1 expression was not observed in gastric cancer cells among the three specimens.

LESSONS

The findings suggest the possibility that PD-L1-positive M2 macrophage might contribute to acceleration of tumor growth with anti-PD-1 therapy in the present case.

Eribulin as a first-line treatment for soft tissue sarcoma patients with contraindications for doxorubicin

Doxorubicin is a first-line therapy for patients with unresectable advanced soft tissue sarcoma (STS). However, because of cardiotoxicities, it is not used for patients with cardiac problems. Eribulin has exhibited efficacy for advanced STS in second- or later-line treatments. In the present study, we retrospectively analyzed the efficacy and safety of first-line eribulin therapy for patients with advanced STS unable to receive doxorubicin. Six of 28 patients who received eribulin as any line treatment received eribulin as a first-line treatment. The reasons for avoiding doxorubicin were as follows: cardiac problems for four patients and advanced age for two. Median progression-free survival (PFS) of the patients who received eribulin as first-line and, second or later-line therapy were 9.7 months (95% CI: 1.0-not reached) and 3.9 months (95% CI: 2.7–5.9), which were not significantly different. The reasons for discontinuation of eribulin were disease progression and adverse events (2 fatigue and 1 neuropathy) for three patients each. No treatment-related cardiotoxicity was observed. The findings of this study indicated that eribulin exhibits meaningful efficacy for the patients with contraindications for doxorubicin as a first-line treatment without cardiac adverse events. However, appropriate safety management is necessary because older patients are typically among those intolerable of doxorubicin.

RNA N6-methyladenosine demethylase FTO regulates PD-L1 expression in colon cancer cells

Fat mass and obesity-associated protein (FTO) is an enzyme that demethylates N6-methyladenosine (m⁶A), the most abundant RNA modifications in a cell. The upregulated expression of FTO promotes the progression of various types of cancer by modulating cell-intrinsic genes which relate to malignant potential. However, the impact of FTO on the expression of immune-checkpoint molecules in the tumor cells, which are important for immune escape, has not been well understood. We examined the relevance of FTO to programmed cell death-ligand 1 (PD-L1) expression in colon cancer cells. HCT-116 cells showed high expression of both FTO and PD-L1 proteins. The knockdown of FTO by small interfering RNA decreased mRNA and protein levels of PD-L1 in HCT-116 cells. To elucidate the underlying mechanism by which FTO regulates the expression of PD-L1, we depleted FTO in HCT-116 in the presence of IFN-γ, which is a major stimulus to upregulate PD-L1 expression. Depletion of FTO reduced PD-L1 expression in an IFN-γ signaling-independent manner. RNA immunoprecipitation assay revealed the m⁶A modification of the PD-L1 mRNA and the binding of FTO to the PD-L1 mRNA in HCT-116. Taken together, our results indicated that FTO could regulate PD-L1 expression in colon cancer cells and provides new insights into the regulation of PD-L1 expression by RNA modification.

OX40 and LAG3 are associated with better prognosis in advanced gastric cancer patients treated with anti-programmed death-1 antibody

Background

Anti-PD-1 monoclonal antibody, nivolumab, has shown efficacy for advanced gastric cancer (AGC). However, the specific immune cell subsets predominantly activated during the period of anti-PD-1 therapy for AGC have not been clarified.

Methods

Peripheral blood of 30 AGC patients treated with nivolumab was prospectively obtained before the initial and second administrations and at the time of progressive disease (PD). The proportions of immune cell subsets and the serum concentrations of cytokines were systematically analysed by flow cytometry. Associations of subsets and serum cytokines with therapeutic effects were evaluated.

Results

After the initial administration, significant increases in activated central/effector memory, activated effector T cells, and activated T-helper 1 subsets were observed. At the time of PD, activated regulatory T cells, LAG3-positive CD4+/CD8+ T cells, and TIM3-positive CD4+/CD8+ T cells increased significantly. Significant positive correlations were shown between progression-free survival and proportions of LAG3-positive CD4+/CD8+ T cells and of OX40-positive CD4+/CD8+ T cells (log-rank p = 0.0008, 0.0003, 0.0035 and 0.0040).

Conclusions

Nivolumab therapy enhances activation of central/effector memory and effector subsets of CD4+/CD8+ T cells. The expression levels of LAG-3 and OX40 on T cells correlated with the efficacy of nivolumab therapy and could be reasonable biomarkers for anti-PD-1 therapy.

Helper T cell-dominant tertiary lymphoid structures are associated with disease relapse of advanced colorectal cancer

Tertiary lymphoid structures (TLSs), clusters of immune cells found around tumor tissue, have been shown to be associated with anti-tumor immunity, but the cellular composition within each TLS and whether the cellular composition of a TLS affects a patient’s prognosis are poorly understood. In the present study, each TLS was categorized according to its cellular composition determined by a system of multiplex immunohistochemical staining and quantitative analysis, and the correlation between the category and prognosis was examined. Sixty-seven patients with curatively resected stage II/III colorectal cancer (CRC) were enrolled. A TLS, consisting of germinal center B cells, follicular dendritic cells, T helper (Th) cells, B cells, cytotoxic T cells, and macrophages, was confirmed in the tumor tissue of 58 patients (87%). The densities of Th cells and macrophages were significantly higher in relapsed patients than in not-relapsed patients (p = .043 and p = .0076). A higher ratio of Th cells was the most significant independent risk factor for disease relapse on multivariate analysis. The subset increasing in Th cells was GATA3⁺ Th2. A total of 353 TLSs was divided into five clusters according to immune cell composition. Among them, the Th-rich type TLS was significantly increased (p = .0009) in relapsed patients. These data suggest the possibility that Th cell-dominant composition might disturb the anti-tumor immune response, and the function of each TLS might differ depending on its composition.

Activation of memory/effector T cells and association between prognosis and OX40-positive T cells in advanced head and neck cancer patients treated with anti-programmed death-1 antibody

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Background: Anti-programmed death-1 (PD-1) monoclonal antibody, nivolumab, enhances anti-tumor activity by inhibiting the interaction of PD-1 and programmed death-1 ligand 1 and has shown efficacy for platinum-refractory recurrent or advanced head and neck cancer (HNC). However, subsets of immune cells predominantly activated during the period of anti-PD-1 therapy for HNC and specifically associated with the prognosis have not been clarified. Methods: Peripheral blood mononuclear cells of 15 HNC patients treated with nivolumab were prospectively obtained before the initial and second administrations of nivolumab, and at the time of progressive disease (PD). We performed comprehensive analysis of the proportion of immune cell subsets by flow cytometry, including the expression of coinhibitory and costimulatory molecules such as T-cell immunoglobulin and mucin domain 3 (TIM-3), lymphocyte-activation gene 3 (LAG-3), T-cell immunoreceptor with Ig and ITIM domains (TIGIT), B and T lymphocyte attenuator (BTLA), CD28, OX40, inducible T cell costimulator (ICOS). Association between changes in the proportion of the subsets and therapeutic effect were also analyzed. Results: Median progression free survival (PFS) of the whole patients was 96 days (95% CI 70–308). After a single course of nivolumab, patients showed a significant increase in activated central memory and effector subsets of CD4+/CD8+ T cells and activated helper T1 cells (p = 0.0039, 0.0078, 0.0273, 0.0391, 0.0391). A trend of increase of activated effector memory CD4+/CD8+ T cell was observed (p = 0.4961, 0.3594). At the time of PD, effector regulatory T cells, LAG3 positive CD4+/CD8+ T cells, TIM-3 positive CD4+/CD8 T cells and BTLA positive CD4+/CD8+ T cells significantly increased. Significant positive correlations were found between PFS and the proportion of OX40 positive CD4+/CD8+ T cells before nivolumab therapy (p = 0.0239, 0.0134). Conclusions: Nivolumab therapy enhances activation of central memory and effector subsets of CD4+/CD8+ T cells. The expression level of OX40 on T cells was correlated with efficacy of nivolumab therapy in HNC patients.

Thrombocytopenia Caused by Dexamethasone in a Patient with Colorectal Cancer

Drug-induced immune thrombocytopenia (DITP) is an important cause of thrombocytopenia. A 73-year-old man with relapsed rectal carcinoma received S-1, oxaliplatin and bevacizumab combination therapy (SOX+Bev). Dexamethasone was administered as an antiemetic prophylaxis. On day 2 of the first cycle, thrombocytopenia (8,000/μL) was observed. We sequentially omitted any drugs suspected to possibly induce thrombocytopenia and confirmed dexamethasone as the cause of thrombocytopenia. DITP induced by synthetic corticosteroids is very rare and this is the first case report of DITP induced by dexamethasone. Although rare, DITP due to synthetic corticosteroids including dexamethasone should be a differential diagnosis among patients receiving synthetic corticosteroids with thrombocytopenia.

Methylation of drug resistance-related genes in chemotherapy-sensitive Epstein-Barr virus-associated gastric cancer

Epstein–Barr virus (EBV)‐associated gastric cancer (GC) is associated with a high degree of DNA methylation. However, the association between chemotherapy susceptibility and tumor DNA methylation in advanced diseases remains unclear. The comprehensive DNA methylation status of GC cells obtained from an advanced EBV‐associated GC (EBVGC) case, in which complete response to S‐1 plus cisplatin chemotherapy was achieved, was analyzed using a DNA methylation microarray. We compared DNA methylation of GC cells with public data and identified genes with higher methylation in EBVGC cell lines than in normal gastric cells, and genes in which methylation was increased by EBV. Of these genes, ABCG2, AHNAK2, BCL2, FZD1, and TP73 are associated with published evidence for resistance to 5‐fluorouracil and cisplatin. Silencing of these genes may be associated with hypersensitivity to chemotherapy.

Abstract 1157: Single-cell transcriptmoics identifies rhamm positive proliferative cells within human colorectal cancer stem cells

Cancer stem cells (CSCs) can be prospectively isolated based on specific surface marker such as CD44, CD133, LGR5, and CD166, in human colorectal cancer. However, the employment of these CSCs' markers are still insufficient to prospectively isolate the colorectal CSCs. To overcome the cellular heterogeneity of previously reported CSCs fraction, we performed single-cell mRNA sequencing (scRNAseq) of 72 cells within organoid. By conducting scRNAseq, we identified CSCs-like sub-population with high expression of MKI67 and Cyclin families, which was generally expressed in proliferative state of the cells within the organoid. Remarkably, high expression of hyaluronan-mediated motility receptor (HMMR) encoding cell membranous and cytoplasmic molecule, receptor for hyaluronan mediated motility (RHAMM), which was reported to associate with CD44 in hyaluronan binding, was observed in the CSCs-like cells. Prospective isolation of RHAMM+ CD44+ cells, that were sub-population of conventional CSCs fraction, revealed higher organoid- and tumor-forming abilities. Furthermore, comprehensive gene expression analysis also demonstrated the proliferative gene expression within RHAMM+ CD44+ cells. Here, we report RHAMM+ proliferative cells that sub-fraction the conventional CSCs population. &lt;!–EndFragment–&gt;

Citation Format: Michitaka Nakano, Kikushige Yoshikane, Kohta Miyawaki, Shinichi Mizuno, Kyoko Yamaguchi, Takuji Yamauchi, Hiroshi Ariyama, Hitoshi Kusaba, Masafumi Nakamura, Takahiro Maeda, Eishi Baba, Koichi Akashi. Single-cell transcriptmoics identifies rhamm positive proliferative cells within human colorectal cancer stem cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1157.

Efficacy and safety of ramucirumab plus modified FOLFIRI for metastatic colorectal cancer

BACKGROUND

Dose modification of chemotherapy for metastatic colorectal cancer (MCRC) is often needed, especially in second-line and later-line treatments due to adverse events of previous treatment and poor patient condition. No study has focused on ramucirumab plus modified dose of FOLFIRI for MCRC, and whether low relative dose intensity (RDI) affects treatment efficacy has not been clarified.

METHODS

MCRC patients who received ramucirumab plus FOLFIRI, which consisted of 150 mg/m2 of irinotecan, at six institutions were retrospectively analyzed.

RESULTS

A total of 43 patients were assessed. Median age was 63 years, and 22 patients (51%) were women. Twenty-six patients (60%) were given ramucirumab plus FOLFIRI as second-line therapy, and 17 (40%) as third or later-line. The median relative dose intensity (RDI) of irinotecan was 60.6%, which is lower than that in the pivotal phase 3 study (RAISE), and other agents showed the same trend. Median progression-free survival was 4.8 [95% confidence interval (CI) 3.2-5.7] months for all patients, 5.4 (95% CI 3.5-7.2) months for second-line patients, and 2.8 (95% CI 1.6-5.8) months for third or later-line patients. Median overall survival was 17.3 (95% CI 11.5-22.4) months for all patients. Patients with irinotecan RDI less than 60% showed similar treatment efficacy. Hematological toxicities of grade 3 or worse were observed in 21 patients, but all were manageable.

CONCLUSION

Low RDI did not compromise the treatment efficacy of ramucirumab plus modified FOLFIRI for MCRC patients.

Activation of central/effector memory T cells in advanced gastric cancer patients treated with antiprogrammed death-1 antibody

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Background: Anti-programmed death-1 (PD-1) monoclonal antibody, nivolumab, enhances antitumor activity by inhibiting the interaction of PD-1 and programmed death-1 ligand 1 (PD-L1) and has shown efficacy for advanced gastric cancer (AGC) in the salvage line. However, specific subsets of immune cells predominantly activated during the period of anti-PD-1 therapy for AGC have not been clarified. Methods: Peripheral blood mononuclear cells of 20 AGC patients treated with nivolumab were prospectively obtained before the initial and second administrations of nivolumab, and at the time of progressive disease (PD). The proportion of immune cell subsets were systematically analyzed by flow cytometry, including the expression of costimulatory and coinhibitory molecules such as T-cell immunoglobulin and mucin domain 3 (TIM-3), Lymphocyte-activation gene 3 (LAG-3), T-cell immunoreceptor with Ig and ITIM domains (TIGIT), cytotoxic T cell antigen-4 (CTLA-4), CD28, OX40, and inducible T cell costimulator (ICOS). Association between changes in the proportion of the subsets and therapeutic effect were analyzed. Results: Median progression free survival (PFS) of the whole patients was 51 days (95% CI 35–83). After a single course of nivolumab, patients showed a significant increase in activated effector memory and activated effector subsets of CD4+/CD8+ T cells (p = 0.018, 0.018, 0.032, 0.024). At the time of PD, proportions of myeloid dendritic cell, IgM memory B cell and Tfh-Th1/17 cell subsets decreased (p = 0.024, 0.013, 0.0039). On the other hand, LAG3 positive CD4+/CD8+ T cells, TIM-3 positive CD4+/CD8 T cells increased at the time of PD (p = 0.013, 0.032, 0.042, 0.042). Significant positive correlations were found between PFS and the proportion of LAG3 positive CD4+/CD8+ T cells (p = 0.0056, 0.0054), OX 40 positive CD4+/CD8+ T cells (p = 0.0034, 0.0006) prior to the initial nivolumab therapy. Conclusions: Nivolumab therapy enhances activation of effector memory and effector subsets of CD4+/CD8+ T cells. The expression level of LAG3 and OX40 on T cells might be correlated with efficacy of nivolumab therapy.

Metastatic esophageal carcinosarcoma comprising neuroendocrine carcinoma, squamous cell carcinoma, and sarcoma: A case report

RATIONALE

Esophageal carcinosarcoma generally comprises 2 histological components: squamous cell carcinoma (SqCC) and sarcoma. Esophageal carcinosarcoma comprising 3 components is extremely rare and no reports have described therapeutic effects for this disease with metastasis.

PATIENT CONCERNS

A 76-year-old man with dysphagia presented to a local clinic. Gastrointestinal endoscopy revealed a polypoid tumor in the middle esophagus and he was referred to our hospital.

DIAGNOSIS AND INTERVENTIONS

Thoracoscopic esophagectomy with super-extended (D3) nodal dissection and gastric tube reconstitution was performed, which resulted in carcinosarcoma comprising neuroendocrine carcinoma (NEC), SqCC, and sarcoma. Pathological stage was T1bN1M0 stage IIB according to the TNM Classification of Malignant Tumors-7th edition. The NEC component was observed in lymph node. At 47 days after surgery, lymph nodes, liver, and bone metastasis appeared, and tumor markers such as ProGRP and NSE were elevated. Combination chemotherapy with cisplatin and etoposide (EP) adapted to NEC was performed.

OUTCOMES

The patient showed complete response within 4 cycles of chemotherapy. However, the disease recurred 5.5 months after the final course of EP chemotherapy.

LESSONS

A therapeutic strategy based on assessment of which component caused metastasis might be important for metastatic carcinosarcoma comprising 3 components, although more accumulation of data about the efficacy of chemotherapy is necessary. Moreover, elucidation of the mechanisms underlying generation of carcinosarcoma is expected in the future.

Epithelial-mesenchymal transition is activated in CD44-positive malignant ascites tumor cells of gastrointestinal cancer

Disseminated cancer cells in malignant ascites possess unique properties that differ from primary tumors. However, the biological features of ascites tumor cells (ATC) have not been fully investigated. By analyzing ascites fluid from 65 gastrointestinal cancer patients, the distinguishing characteristics of ATC were identified. High frequency of CD44⁺ cells was observed in ATC using flow cytometry (n = 48). Multiplex quantitative PCR (n = 15) showed higher gene expression of epithelial‐mesenchymal transition (EMT)‐related genes and transforming growth factor beta (TGF‐beta)‐related genes in ATC than in the primary tissues. Immunohistochemistry (n = 10) showed that ATC also had much higher expression of phosphorylated SMAD2 than that in the corresponding primary tissues. TGF‐beta 1 was detected in all cases of malignant ascites by enzyme‐linked immunoassay (n = 38), suggesting the possible interaction of ATC and the ascites microenvironment. In vitro experiments revealed that these ATC properties were maintained by TGF‐beta 1 in cultured ATC(n = 3). Here, we showed that ATCrevealed high frequencies of CD44 and possessed distinct EMT features from primary tissues that were mainly maintained by TGF‐beta 1 in the ascites.

PD-1+ TIM-3+ T cells in malignant ascites predict prognosis of gastrointestinal cancer

The liquid biopsy of ascites fluid could be an excellent source of tumor and microenvironment for the study of prognostic biomarkers because of its accessibility. Tumor-infiltrating lymphocytes (TILs) can predict prognosis in multiple malignancies, including the response to immune checkpoint inhibitors, a breakthrough cancer therapy. However, TILs' profiles from malignant ascites have not been extensively studied. Using flow cytometric analysis, we quantified the proportion of exhausted T cells and memory/naive/effector T-cell subsets, among the CD4+ and CD8+ T-cell populations of paired TILs and peripheral blood T cell samples (n = 22). The correlation between CD4+ and CD8+ subset profiles suggested that the combined analysis of CD4+ and CD8+ cells in malignant ascites was clinically significant. We found that cells positive for the exhaustion markers programmed cell death-1 (PD-1), and T-cell immunoglobulin and mucin domain 3 (TIM-3), and cells coexpressing PD-1 and TIM-3 abundantly exist among malignant ascites TILs. Furthermore, patients with high frequency of PD-1+ TIM-3+ cells among the CD4+ and CD8+ T-cell population showed worse clinical outcome in multivariate analysis (n = 27). We propose that exhausted ascites TILs represent a clinically significant prognostic biomarker in advanced gastrointestinal cancer and represent an important target for immune checkpoint inhibitors.

Activation of central/effector memory T cells and T-helper 1 polarization in malignant melanoma patients treated with anti-programmed death-1 antibody

Human anti-programmed death-1 (PD-1) antibody possesses the capability to revitalize host T cells and has been an effective therapy for metastatic malignant melanoma (MM). The precise subsets of T cells predominantly activated by anti-PD-1, however, have not yet been clarified. In this study, peripheral blood mononuclear cells obtained from MM patients scheduled to receive anti-PD-1 (nivolumab) therapy, and healthy subjects (HS), were systematically examined on flow cytometry to identify changes in the proportion of immune cell subsets. Compared with HS, MM patients prior to therapy had an increased proportion of activated CD8+ T cells with effector memory phenotypes (Tem), and PD-1 positive subsets of CD4+ central memory T cells (Tcm) and T-helper (Th)17 cells. After a single course of anti-PD-1 therapy, MM patients had an increase in activated Tem and Tcm subsets of CD4+ and CD8+ T cells, and activated Th1 plus T-helper follicular 1 cells. There was no consistent change in the proportion of Tfh cells, B cells, natural killer cells, or dendritic cells. The observed activated phenotypes were attenuated during the course of therapy, but regulatory T cells belonging to the CD3+CD4+CD45RO+CD25high fraction increased at disease progression. Taken together, anti-PD-1 therapy modulates systemic immune reactions and exerts anti-tumor effects, not only by revitalizing Tem and Tcm of CD4+ and CD8+ T cells, but also via a shift to a Th1 phenotype.

The risk factors for oxaliplatin-induced peripheral sensory neuropathy and thrombocytopenia in advanced gastric cancer

PURPOSE

Peripheral sensory neuropathy (PSN) and thrombocytopenia are the main dose-limiting toxicities of oxaliplatin for the treatment of advanced gastric cancer (AGC). Because the risk factors for those toxicities in practice have not been clarified, we conducted this prospective study.

METHODS

AGC patients who received oxaliplatin-based therapy at any of seven institutions participating in the Kyushu Medical Oncology Group were assessed after we obtained written informed consent.

RESULTS

A total of 60 patients including 39 males and 21 females were examined. The median age was 66 years. The numbers of patients receiving oxaliplatin as the first, second, or third and later lines of therapy were 39, 16, and 5, respectively. An initial dose of 130, 100, or < 100 mg/m² oxaliplatin was administered to 12, 39, and 9 patients, respectively. S-1 or capecitabine as a concomitant drug was administered in 54 and 6 patients, respectively. In multivariate analysis, the comorbidity of diabetes mellitus was associated with ≥ grade 2 thrombocytopenia (p = 0.035). No significant risk factor was associated with ≥ grade 2 PSN. However, the accumulated dose of oxaliplatin exhibited a strong correlation with ≥ grade 2 PSN (p = 0.0043), and the predicted accumulated dose of oxaliplatin in which 10% of patients developed ≥ grade 2 PSN was 800 mg/m². The frequency of PSN in subsequent paclitaxel therapy in patients with ≥ grade 2 or worse PSN in oxaliplatin-based chemotherapy did not increase compared to those with none or grade 1 PSN in oxaliplatin.

CONCLUSION

Thrombocytopenia in AGC patients with diabetes mellitus should be carefully monitored during oxaliplatin-based therapy.

A phase 2 study of fosaprepitant combined with high-dose dexamethasone for Japanese cancer patients receiving highly emetogenic chemotherapy

PURPOSE

Combination therapy of fosaprepitant, dexamethasone (DEX) and a serotonin (5-HT3) receptor antagonist is a standard antiemetic prophylaxis for patients receiving highly emetogenic chemotherapy (HEC). However, the appropriate dose of DEX has not been established in Japan. This study determined the efficacy and safety of triplet antiemetic prophylaxis in Japanese patients receiving HEC when administered the same doses of DEX as those given in a previous international phase 3 study on this drug.

METHODS

To assess the efficacy and safety of a sufficient dose of DEX (12 mg on day 1, 8 mg on day 2, 16 mg on days 3 and 4) in combination with intravenous fosaprepitant and granisetron, we prospectively examined patients receiving HEC including cisplatin (≥50 mg/m). The primary endpoint was to determine the percentage of patients who had achieved a complete response (CR), which was defined as no vomiting and no rescue therapy during the entire treatment course.

RESULTS

Between February 2013 and January 2015, 44 patients were enrolled with a median age of 65 years (range, 30-75). There were 34 males (77.3%) in the study. Most of the patients had upper gastrointestinal cancers. The CR rate during the treatment course was 70% (95% confidence interval [CI]: 55%-83%) in the overall phase and 91% (95% CI: 78%-97%) in the acute phase and 70% (95% CI: 55%-83%) in the delayed phase. Appreciable severe toxicities related to the antiemetic therapy were not observed.

CONCLUSIONS

These results suggest that a sufficient dose of DEX in combination with fosaprepitant and granisetron is optimal as an antiemetic prophylaxis for Japanese patients receiving HEC.

E‑cadherin regulates proliferation of colorectal cancer stem cells through NANOG

Cancer stem cells (CSCs) possess a self-renewal ability and display tumorigenic potential in immunodeficient mice. Colorectal CSCs are thought to be a uniform population and no functionally distinct subpopulations have been identified. Because E-cadherin is an essential molecule for self-renewal of embryonic stem cells, we examined E-cadherin expression, which may play a role in maintaining the properties of CSCs, in EpCAM^high/CD44⁺ colorectal CSCs from human primary colorectal cancers. We obtained 18 surgical specimens of human primary colorectal cancer. CD44, EpCAM, and E-cadherin expression were analyzed by fluorescence-activated cell sorting. Sorted EpCAM^high/CD44⁺ colorectal CSCs were injected into immunodeficient mice to estimate the tumorigenic potential. Genetic profiles were analyzed by cDNA microarray. Notably, colorectal CSCs could be divided into two populations based on the E-cadherin expression status, and they exhibited different pathological characteristics. Compared to E-cadherin-negative colorectal CSCs, E-cadherin-positive (EC⁺) colorectal CSCs demonstrated higher tumor growth potential in vivo. EC⁺ colorectal CSCs revealed a higher expression of the pluripotency factor NANOG, which contributed to the higher tumor growth potential of EC⁺ colorectal CSCs through control of cyclin D1 expression. These findings are the first demonstration of functionally distinct subpopulations of colorectal CSCs in human clinical samples.

Successful chemotherapeutic treatment for metastatic littoral cell angioma: A case report

RATIONALE

Metastatic littoral cell angioma (LCA) is extremely rare. No standard therapeutic strategy has been established, and the impact of chemotherapy has not yet been evaluated.

PATIENT CONCERNS

A 61-year-old woman was admitted because of bicytopenia. She had a splenectomy for LCA of the spleen 10 years earlier. Bone marrow aspiration was normal, and a computed tomography (CT) scan showed hepatomegaly with multiple liver tumors.

DIAGNOSES

Liver biopsy samples showed macrophage-like cell infiltration in the hepatic sinusoids. Metastatic LCA was diagnosed based on immunohistochemistry, imaging tests, and the clinical course.

INTERVENTIONS

Immunosuppressive agents, such as prednisolone and cyclosporine, were ineffective. Next, cytotoxic agents, such as etoposide, paclitaxel, and vincristine, were administered.

OUTCOMES

Cytotoxic agents showed a prominent effect against LCA. CT showed improvement of the hepatomegaly, and fluoro-deoxyglucose (FDG) uptake decreased markedly at a follow-up FDG- positron emission tomography (PET) scan.

LESSONS

Chemotherapeutic treatment based on hemophagocytic syndrome or angiosarcoma might have anti-tumor activity against metastatic LCA. Analysis of the molecular characteristics of this tumor is needed to develop better treatment options.

Metastatic esophageal cancer presenting as shock by injury of vagus nerve mimicking baroreceptor reflex: A case report

RATIONALE

Neurogenic shock is generally typified by spinal injury due to bone metastases in cancer patients, but continuous disturbance of the vagus nerve controlling the aortic arch baroreceptor can cause shock by a reflex response through the medulla oblongata.

PATIENT CONCERNS

A 43-year-old woman with dysphagia presented to our hospital. Computed tomography showed a primary tumor adjacent to and surrounding half the circumference of the descending aorta, and multiple cervical lymph node metastases, including a 55 × 35-mm lymph node overlapping the root of the left vagus nerve. Squamous esophageal cancer (T4bN3M1, stage IV) was diagnosed. Whereas shock status initially appeared soon after left cervical pain, suggesting pain-induced neutrally-mediated syncope, sustained bradycardia and hypotension occurred even after alleviation of pain by opioids.

DIAGNOSIS

Disturbance of the left vagus nerve associated with the aortic arch baroreceptor by a large left cervical lymph node metastasis was considered as the cause of shock, pathologically mimicking the baroreceptor reflex.

INTERVENTIONS

Systemic steroid administration was performed, and radiotherapy for both the primary site and lymph node metastasis was started 2 days after initiating steroid treatment.

OUTCOMES

Four days after initiating steroid administration, hypotension and bradycardia were improved and stable.

LESSONS

Disturbance of the vagus nerve controlling the aortic arch baroreceptor should be kept in mind as a potential cause of neurogenic shock in cancer patients, through a pathological reflex mimicking the baroreceptor reflex.

CXCR4-expressing Mist1+ progenitors in the gastric antrum contribute to gastric cancer development

Mist1 was recently shown to identify a discrete population of stem cells within the isthmus of the oxyntic gland within the gastric corpus. Chief cells at the base of the gastric corpus also express Mist1. The relevance of Mist1 expression as a marker of specific cell populations within the antral glands of the distal stomach, however, is unknown. Using Mist1-CreERT mice, we revealed that Mist1⁺ antral cells, distinct from the Mist1⁺ population in the corpus, comprise long-lived progenitors that reside within the antral isthmus above Lgr5⁺ or CCK2R⁺ cells. Mist1⁺ antral progenitors can serve as an origin of antral tumors induced by loss of Apc or MNU treatment. Mist1⁺ antral progenitors, as well as other antral stem/progenitor population, express Cxcr4, and are located in close proximity to Cxcl12 (the Cxcr4 ligand)-expressing endothelium. During antral carcinogenesis, there is an expansion of Cxcr4⁺ epithelial cells as well as the Cxcl12⁺ perivascular niche. Deletion of Cxcl12 in endothelial cells or pharmacological blockade of Cxcr4 inhibits antral tumor growth. Cxcl12/Cxcr4 signaling may be a potential therapeutic target.

Lingual alveolar soft part sarcoma responsive to pazopanib: A case report

RATIONALE

The multi-targeted tyrosine kinase inhibitors such as cediranib, sunitinib and pazopanib have been reported to be effective for alveolar soft part sarcoma (ASPS). The efficacy of pazopanib for the patient with lingual ASPS has yet to be reported.

PATIENT CONCERNS

A 23-year old man presented with articulation disorder and swelling of the tongue. Diagnosis of lingual ASPS was made after incisional biopsy and complete excision of the mass was performed. Three months later, he presented with a protruding mental region.

DIAGNOSES

Computed tomography revealed mental region mass and lung metastasis.

INTERVENTIONS

After the failure of combination therapy of doxorubicin and ifosfamide, pazopanib was administered.

OUTCOMES

Shrinkage of both the mental region and lung mass continued for more than two months, but regrowth was confirmed at the fourth month.

LESSONS

Lingual ASPS is an exceedingly rare subset of ASPS with distinct molecular and histological characteristics and appropriate therapy remains to be established. Our findings suggest a possible therapeutic strategy for lingual ASPS.

Retrospective analysis of cardiovascular diseases related to chemotherapies for advanced solid tumor patients

Appropriate management of cardiovascular diseases (CVDs) related to chemotherapy for solid tumors is important for safe oncologic treatment. However, prediction of the onset and progression of CVDs has not generally been established in Japan. We carried out a retrospective analysis of advanced or recurrent solid tumor patients who received chemotherapies in a single institution. Patient characteristics, chemotherapy regimens, adverse events, CVDs before chemotherapy, and diagnosis of CVDs in association with chemotherapy were assessed. During the period from April 2006 to March 2012, 394 patients were examined. Cardiac diseases (CDs), hypertension (HT), or arterial thrombosis or venous thromboembolism were prevalent in 37 (9.4%), 22 (5.6%), five (1.3%), and 14 (3.5%) cases, respectively. HT (14.5%) and venous thrombosis (5.8%) were frequent in patients who received bevacizumab-containing chemotherapy. Four cases with left ventricular dysfunction experienced a decrease of ejection fraction and early filling/atrial filling (E/A) and E/A tended to decrease before ejection fraction. Ninety (62.1%) of 145 cases showed an increase in the D-dimer (DD) level before chemotherapy, and a further increase in DD level was found when venous thrombosis occurred. Relative risks of the disease progression of HT, CD, and thromboembolism because of chemotherapy were 1.3, 1.9, and 3.6, respectively. A decrease in E/A and an increase in DD were suggested to be valuable for early diagnosis of the respective onsets of left ventricular dysfunction and venous thrombosis related to chemotherapy. We conclude that patients with previous CD tend to have disease progression of CD during chemotherapy.

Regorafenib-induced retinal and gastrointestinal hemorrhage in a metastatic colorectal cancer patient with liver dysfunction: A case report

RATIONALE

Regorafenib is effective for metastatic colorectal cancer but its toxicity such as hemorrhage should be considered. The safety of regorafenib for the patient with the liver disease is not known.

PATIENT CONCERNS

Seventy-one-year old man of colon cancer had myodesopsia and blood stool after 14 days from the initiation of regorafenib administration with 50% dose reduction due to liver dysfunction.

DIAGNOSES

Fundus examination revealed hemorrhage of the retinal vein.

INTERVENTIONS

Regorafenib treatment was discontinued and observational therapy was pursued.

OUTCOMES

Retinal and gastrointestinal hemorrhage resolved in 1 week.

LESSONS

Retinal hemorrhage should be considered as the differential diagnosis of myodesopsia in the patient treated by regorafenib. Safety and pharmacokinetic of continuous regorafenib administration for patients with liver dysfunction remains to be clarified.

Suggestion of added value by bevacizumab to chemotherapy in patients with unresectable or recurrent small bowel cancer

PURPOSE

Standard therapy for advanced small bowel adenocarcinoma (SBA) has not yet been established. The present study assessed the efficacy and safety of chemotherapy (CT) in association with molecular targeting approaches for SBA.

METHODS

The histories of 33 advanced SBA patients from six different institutions in Japan, who received CT from 2008 to 2016, were retrospectively examined for background, clinical course and outcome.

RESULTS

Median patient age was 65 years (range 39-83). Primary tumor was located in the duodenum in 21 patients (67%), the ampulla of Vater in three patients (9%), the jejunum in seven patients (21%) and the ileum in one patient (3%). Histologically, well-to-moderately and poorly differentiated adenocarcinoma were identified in 20 (61%) and nine (27%) patients, respectively. Thirteen patients received a single CT regimen, seven patients received two types of CT regimen, and 13 patients received three or more CT regimens. As first-line CT, modified FOLFOX6, capecitabine plus oxaliplatin, and S-1 plus cisplatin were employed in 13, 1, and 4 patients, respectively. The response rate (RR) and median progression-free survival (PFS) were 25% and 6.0 months, respectively. Median overall survival (OS) was 13.0 months. Nine out of the 33 patients received bevacizumab-containing CT and three received cetuximab-containing CT. Median OS of bevacizumab-containing CT patients was 21.9 months. No unexpected serious adverse events were observed.

CONCLUSIONS

The analysis indicates that combination CT for advanced SBA is associated with modest efficacy and safety, and bevacizumab-containing CT may contribute to favorable outcome in these patients.

Systemic chemotherapy with pronounced efficacy and neutropenia in a granulocyte-colony stimulating factor-producing advanced gastric neuroendocrine carcinoma

An advanced granulocyte-colony stimulating factor (G-CSF)-producing tumor is rare, and it exhibits leukocytosis in association with high serum G-CSF levels. A 67-year-old male with a 1-month history of bloody emesis and black stools was revealed to exhibit leukocytosis, anemia and a high serum concentration of G-CSF. During a gastrointestinal endoscopy, an ulcerating tumor was identified in the stomach. Computed tomography and a fluorodeoxyglucose-positron emission tomography scan demonstrated direct invasion of the gastric tumor into the transverse colon, regional lymphadenopathy, lung nodules and diffuse high uptake of FDG in bone marrow. The histological diagnosis was a G-CSF-producing neuroendocrine carcinoma (NEC) (tumor 4b, node 2, metastasis 1, pulmonary, clinical stage IV). Systemic chemotherapy consisting of cisplatin and irinotecan was started. Common terminology criteria of adverse events grade 3 tumor lysis syndrome and gastric penetration appeared. Grade 4 neutropenia lasted for 10 days despite intensive G-CSF administration. Prominent shrinkage of the primary and the metastatic tumors was observed subsequent to 3 cycles of chemotherapy. Total gastrectomy and resection of the transverse colon were subsequently performed. Systemic chemotherapy was effective for a G-CSF-producing advanced gastric NEC with careful monitoring and appropriate supportive care for severe adverse events.

Pancreatic acinar cell carcinoma presenting with panniculitis, successfully treated with FOLFIRINOX: A case report

Pancreatic acinar cell carcinoma (PACC) is a rare tumor of the exocrine pancreas, representing only 1% of all pancreatic malignancies. A 50-year-old man presented with edema of the thumb joints bilaterally, followed by an appearance of masses in the bilateral lower extremities and fever (38°C). The masses were diagnosed as panniculitis by skin biopsy, and multiple intraperitoneal masses were incidentally detected on pelvic magnetic resonance imaging performed to investigate the leg abnormalities. The patient was referred to the Kyushu University Hospital for further investigation, and fluorodeoxyglucose-positron emission tomography/computed tomography (CT) revealed high-uptake tumors in the pancreatic tail, in the periphery of the liver, and in the pelvis. Laboratory examinations revealed high serum concentrations of pancreatic exocrine enzymes, such as lipase, trypsin, elastase 1 and pancreatic phospholipase A2. Histological examination of a bioptic specimen obtained from a hepatic lesion revealed proliferation of atypical cells arranged in a tubular or glandular pattern. Immunohistochemical staining revealed that the atypical cells were positive for cytokeratin (CK)7, CK19 and lipase, but negative for CK20 and thyroid transcription factor-1, leading to a final diagnosis of acinar cell carcinoma of the pancreatic tail (T4bN0M1, stage IV according to the 7th edition of the TNM Classification of Malignant Tumors). Combined chemotherapy with oxaliplatin, irinotecan and fluorouracil (FOLFIRINOX) was administered and fever was soon alleviated. The serum levels of lipase also declined and panniculitis completely resolved. As of the start of the 8th course of chemotherapy, the levels of the pancreatic exocrine enzymes were within normal ranges and CT revealed partial response. Therefore, the severe lipase hypersecretion syndrome was well controlled by the FOLFIRINOX regimen and shrinkage of the mass was also achieved. Thus, the FOLFIRINOX regimen may represent an effective treatment option for advanced PACC.

Programmed death-ligand 1 expression is associated with fibrosarcomatous transformation of dermatofibrosarcoma protuberans

Dermatofibrosarcoma protuberans (DFSP) is a locally invading tumor, characterized by the presence of the collagen type I α 1 (COL1A1)-platelet-derived growth factor (PDGF) β fusion gene. We herein report the case of a 31-year-old man with a history of resection of an abdominal wall DFSP. The patient presented with chest pain and a computed tomography scan revealed a large mass in the posterior mediastinum and another mass in the right lung. The mediastinal mass was a sarcomatous lesion expressing the COL1A1-PDGFβ fusion gene, suggesting that it represented a metastasis of the DFSP following fibrosarcomatous (FS) transformation. Following resection of the mediastinal metastasis and subsequent radiotherapy, the mass in the right lung was also resected. Due to the emergence of pleural and pancreatic tail metastases, the patient was treated with a combination therapy of adriamycin and ifosfamide. After five courses, the disease progressed and the patient was subsequently treated with pazopanib for ~2 months until further progression. Three years after the diagnosis of the mediastinal metastasis of DFSP, the patient was referred to another hospital for palliative care. The expression of programmed cell death 1 ligand (PD-L1) in the primary and metastatic tumors was investigated: PD-L1 expression was detected in the metastasis but not in the primary tumor. Given that the metastatic tumor exhibited FS transformation (DFSP-FS), PD-L1 expression may be induced by FS transformation, contributing to the metastasis through escape from immune surveillance. Further investigation of the PD-L1 pathway in DFSP and DFSP-FS in primary as well as metastatic sites is required to evaluate the clinical efficacy of therapies targeting the PD-L1 signaling cascade.

Cardiac metastasis of squamous cell carcinoma of the thyroid gland with severe disseminated intravascular coagulation: A case report

Distant metastasis of primary squamous cell carcinoma (SCC) of the thyroid gland is rare and, to the best of our knowledge, cardiac metastasis has not been reported to date. A 57-year-old man underwent surgery and adjuvant chemoradiotherapy for stage IVA SCC of the thyroid gland. After 3 months, the patient was admitted to the Kyushu University Hospital (Fukuoka, Japan) with subcutaneous hematomas of the left thigh and lower leg, and he was diagnosed with cardiac and mediastinal lymph node metastases of SCC of the thyroid gland with severe disseminated intravascular coagulation (DIC). Echocardiography revealed a mass, 52 mm in greatest diameter, protruding from the interventricular septum towards the right ventricle. Weekly administration of paclitaxel and concurrent irradiation of the cardiac and lymph node metastases were performed. Eighteen days after the initiation of chemoradiotherapy, the DIC and hematomas had significantly improved, and the cardiac metastasis was stable. However, 2 months after admission, the patient developed dyspnea and multiple nodular shadows appeared to be spreading in the subpleura of the lungs bilaterally, which were initially suspected to be pulmonary tumor embolisms. Prednisolone and subsequent administration of lenvatinib were not effective and the patient succumbed to respiratory failure. Severe DIC caused by extremely rare cardiac metastasis of SCC of the thyroid gland was effectively controlled by chemoradiotherapy. However, intensive local control appears to be required for this condition.

Efficacy analysis of the aprepitant-combined antiemetic prophylaxis for non-round cell soft-tissue sarcoma patients received adriamycin and ifosfamide therapy

Appropriate antiemetic prophylaxis for moderately emetogenic chemotherapy in patients with non-round cell soft-tissue sarcomas (NRC-STS) remains unclear. We retrospectively investigated efficacy and safety of aprepitant-combined antiemetic prophylaxis in patients with NRC-STS receiving adriamycin plus ifosfamide (AI) therapy. Forty NRC-STS patients were enrolled, their median age was 50 years (range 18-74), and 13 (32.5%) were female. Median cycle number of AI therapy was 4. Twenty patients received the doublet antiemetic prophylaxis (5-hydroxytryptamine-3 receptor antagonist and dexamethasone), and 20 received triplet (5-hydroxytryptamine-3 receptor antagonist, dexamethasone, and aprepitant). In the overall period, complete response rate for nausea and emesis in the triplet group was significantly higher than that in the doublet group (70% vs 35%; P = 0.027). Patients with no-emesis in the overall period were more frequently observed in the triplet group than in the doublet group (90% vs 65%; P = 0.058). All toxicities other than emesis were almost equivalent in both the groups. These results suggest that a triplet antiemetic prophylaxis may be optimal in the treatment with AI therapy for NRC-STS.

Favorable control of advanced colon adenocarcinoma with severe bone marrow metastasis: A case report

Colorectal cancer (CRC) has a propensity to metastasize to the liver, lungs and regional abdominal lymph nodes, but rarely to the bone marrow. A 60-year-old man presented to the National Hospital Organization Kyushu Cancer Center with a 4-week history of persistent lower back pain, anorexia and difficulty defecating. Complete blood count revealed severe thrombocytopenia and erythroblastosis, suggesting a hematological malignancy. However, the bone marrow examination demonstrated involvement by a moderately to poorly differentiated adenocarcinoma, but no hematopoietic abnormalities. A computed tomography scan revealed thickening of the wall of the sigmoid colon, with para-aortic, hilar, mediastinal and supraclavicular lymphadenopathy. The patient was thus diagnosed with sigmoid colon adenocarcinoma with lymph node and bone marrow metastasis. Modified FOLFOX6 was promptly initiated, with concurrent therapy for disseminated intravascular coagulation (DIC). An increased number of thrombocytes was observed on day 6. After 3 cycles of treatment, the patient recovered from DIC and the levels of serum carcinoembryonic antigen and cytokeratin 19 fragment were decreased. Tumor biopsy during colonoscopy following recovery from DIC demonstrated poorly differentiated adenocarcinoma with mucin production, without mutations in the RAS, BRAF or PIK3CA genes, and a cytokeratin (CK) 7-negative, CK20-positive phenotype. The patient has been treated with chemotherapy for 150 days without disease progression. However, the efficacy of chemotherapy for rarely encountered bone marrow metastasis from CRC is poor. The present case was favorably maintained on chemotherapy and survived for 10 months.

Abstract 714: Macrophage-to-fibroblast transition promotes cancer progression in peritoneal carcinomatosis of gastrointestinal cancer patient

[Background] Cancer stromal cell plays an important role in cancer progression. Fibroblasts localized in tumor are especially called cancer-associated fibroblasts (CAFs). CAFs and inflammatory cells form tumor microenvironment and promote cancer growth through the direct or indirect interaction between cancer cells and stromal cells. However, the origin of CAF is not fully understood. Malignant ascites contains not only cancer cells but inflammatory cells including macrophage. Accumulation of macrophages and fibrosis has close relationship. In the research field of fibrotic diseases such as renal fibrosis, some reports indicated macrophages were able to change to fibroblasts phenotypically. Peritoneal carcinomatosis also develops peritoneal fibrosis. We demonstrate that malignant ascites are abundant in macrophages and these macrophages changed to CAFs which promote cancer progression in vivo. [Material and method] Ascitic samples from 44 peritoneal carcinomatosis patients due to gastrointestinal cancer were collected at 5 institutions. This study was approved by each institutional review board. Ascites was separated into cell fraction and supernatant by centrifugation. Supernatant was stored at -20°C. Cells were sorted by FACS using anti-CD45, anti-CD14, anti-CD163 and anti-CD90 antibodies. CD45+CD14+ macrophages were cultured in RPMI medium containing fetal bovine serum (FBS) or supernatant of ascites. Human colorectal cancer cell line DLD-1 cells in combination with the cultured cells from ascites were inoculated to immunodeficient mice subcutaneously. All experiments were conducted following the guidelines of the institutional animal committee of Kyushu University. [Result] CD45+CD14+ macrophage was most frequently observed in CD45+ leukocyte fraction from ascites. Most of macrophages expressed M2 marker (CD163). Some of these macrophages changed to CD45-CD90+ fibroblast-like cells which form spindle shape after 2-3 weeks culture. These fibroblast-like cells expressed fibroblast specific genes such as COL3A1, ACTA2 and FAP. These changes were enhanced by ascites supernatant-containing medium compared with FBS-containing medium. DLD-1 cells with the fibroblast-like cells formed larger tumors in immunodeficient mice, compared with DLD-1 cells alone. [Conclusion] In peritoneal carcinomatosis, macrophage is a potential source of CAF. This macrophage-to-CAF transition is enhanced by malignant ascitic environment. As CAF induced from macrophage enhances tumor progression, inhibition of this transition could be possible therapeutic strategy.

Citation Format: Mamoru Tanaka, Michitaka Nakano, Hiroshi Ariyama, Kyoko Inadomi, Risa Tanaka, Shigeo Takaishi, Hitoshi Kusaba, Eishi Baba, Koichi Akashi. Macrophage-to-fibroblast transition promotes cancer progression in peritoneal carcinomatosis of gastrointestinal cancer patient. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 714.

Bi-cytopenia possibly induced by anti-PD-1 antibody for primary malignant melanoma of the esophagus: A case report

BACKGROUND

Anti-programmed cell death 1 antibody nivolumab is a promising agent for various cancers. Immune-related adverse events are recognized; however, bi-cytopenia with nivolumab has not been reported.

CASE PRESENTATION

A 73-year-old man was diagnosed with advanced primary malignant melanoma of the esophagus with liver, lung, and lymph node metastases. Previous therapies including dacarbazine and radiation of 39 Gy to the esophageal region were performed, but the liver metastases deteriorated. The patient was then administered nivolumab (2 mg/kg, every 3 weeks). After 3 cycles, the esophageal tumor and lymph nodes showed marked reductions in size, the lung metastases disappeared, and the liver metastases shrank partially. The treatment continued with 7 cycles for 4 months. However, severe anemia and thrombocytopenia appeared in the 6th cycle, and intermittent blood transfusions were required. The patient received high-dose intravenous methylprednisolone therapy for bi-cytopenia, but it was ineffective. Seven months after the initiation of nivolumab, the patient died of tumor. Although the mechanisms of bi-cytopenia were unclear, it could have been induced by nivolumab.

CONCLUSION

The present case shows a rare but serious life-threatening bi-cytopenia possibly associated with nivolumab and suggests the importance of awareness of hematological adverse events during nivolumab therapy.

Efficacy and Safety of TAS-102 in Clinical Practice of Salvage Chemotherapy for Metastatic Colorectal Cancer

BACKGROUND

TAS-102 is an anti-metabolite which demonstrated activity against multidrug-resistant advanced colorectal cancer. Its major toxicities are hematological disorders.

PATIENTS AND METHODS

Background, TAS-102 efficacy, toxicities and outcomes for patients with multidrug-resistant advanced colorectal cancer from six Institutions of the Kyushu Medical Oncology Group were retrospectively surveyed.

RESULTS

Forty-three patients, including fragile patients due to declining performance status and other comorbidities (37%) were analyzed. Efficacy was reflected in an objective overall response of 3%, median progression-free survival of 74 days (2.5 months) and median overall survival of 229 days (7.6 months). The most frequent Common Terminology Criteria for Adverse Events grade 3/4 adverse events were neutropenia (44%), leukopenia (26%) and anemia (23%). Febrile neutropenia was found in 7%. Sub-group analysis demonstrated an improved outcome on treatment with the sequence regorafenib-TAS-102.

CONCLUSION

TAS-102 was safely administered to modestly fragile patients with equivalent efficacy to that for the non-fragile population. Further investigation of sequential treatment using regorafenib and TAS-102 is needed.

Mist1 Expressing Gastric Stem Cells Maintain the Normal and Neoplastic Gastric Epithelium and Are Supported by a Perivascular Stem Cell Niche

The regulation and stem cell origin of normal and neoplastic gastric glands are uncertain. Here, we show that Mist1 expression marks quiescent stem cells in the gastric corpus isthmus. Mist1(+) stem cells serve as a cell-of-origin for intestinal-type cancer with the combination of Kras and Apc mutation and for diffuse-type cancer with the loss of E-cadherin. Diffuse-type cancer development is dependent on inflammation mediated by Cxcl12(+) endothelial cells and Cxcr4(+) gastric innate lymphoid cells (ILCs). These cells form the perivascular gastric stem cell niche, and Wnt5a produced from ILCs activates RhoA to inhibit anoikis in the E-cadherin-depleted cells. Targeting Cxcr4, ILCs, or Wnt5a inhibits diffuse-type gastric carcinogenesis, providing targets within the neoplastic gastric stem cell niche.