Economic evaluation of nivolumab combined with ipilimumab in the first-line treatment of advanced melanoma in Japan.

AIMS: The objective of this study was to evaluate the cost-effectiveness of nivolumab in combination with ipilimumab (nivo + ipi) compared to current therapeutic alternatives in first-line treatment of patients with advanced melanoma from the Japanese national healthcare payer perspective using 48-month survival data from the CheckMate 067 Phase III trial. MATERIALS AND METHODS: A three-state partitioned survival model was developed from projections of overall survival (OS) and progression-free survival (PFS) to estimate accrued quality-adjusted survival and costs over a 30-year time horizon. The analysis included nivo + ipi, nivolumab, and ipilimumab monotherapies (the three treatments included in CheckMate 067). Drug acquisition, administration, disease management, subsequent therapy, and adverse event (AE) costs were obtained via published sources and expert input (solicited via Delphi panel). AE frequencies were collected from the Checkmate 067 trial. Utility weights were estimated from the Checkmate 067 trial, based on Japanese tariffs. Results were presented as incremental cost-utility ratios (ICURs, cost per quality-adjusted life-year (QALY)). RESULTS: Nivo + ipi had the greatest estimated survival among the three competing treatments, followed by nivolumab monotherapy accruing the second greatest survival. The incremental cost-effectiveness of nivo + ipi was ¥778,000 per QALY vs. nivolumab and ¥1,584,000 per QALY vs. ipilimumab. The results indicate that nivo + ipi is cost-effective in Japan when compared to a threshold of ¥7,500,000 per QALY. This finding was found to be generally robust to sensitivity and scenario analyses. LIMITATIONS: Limitations include uncertainty in long-term survival extrapolations and lack of Japan-specific clinical data. CONCLUSIONS: This analysis indicates that adding ipilimumab to nivolumab therapy represents a cost-effective new treatment option for patients with unresectable malignant melanoma in Japan.

Real-world safety and efficacy data of ipilimumab in Japanese radically unresectable malignant melanoma patients: A postmarketing surveillance.

Treatment with immune checkpoint inhibitors has improved prognosis among patients with cutaneous melanoma, but there are still unmet medical needs in Japan, especially for mucosal melanoma and acral lentiginous melanoma (ALM) subtypes. Ipilimumab, a fully human monoclonal antibody that specifically blocks cytotoxic T-lymphocyte-associated antigen 4 and potentiates antitumor T-cell response, was approved in Japan in 2015 for the treatment of radically unresectable malignant melanoma. This postmarketing surveillance (prospective, non-interventional, multicenter, observational study) evaluated the safety (occurrence of adverse drug reactions [ADR]) and efficacy (overall survival [OS]) of ipilimumab in a real-world setting in Japan. All patients with radically unresectable malignant melanoma undergoing treatment with ipilimumab in Japan during the registration period between August 2015 and February 2017 were enrolled. In total, 547 patients were analyzed; 67.5% were 60 years old or more, 85.7% had an Eastern Cooperative Oncology Group performance status of 0-1, 50.3% had melanoma of the skin (mainly of the ALM subtype) and 73.5% had negative BRAF mutation status. Most patients had experienced recurrence and received multiple treatments. The overall incidence of ADR and serious ADR was 69.5% and 40.8%, respectively. The most common ADR and serious ADR were liver disorder, colitis and diarrhea. The most common ADR of special interest were liver-related ADR (22.5%), skin-related ADR (22.1%), gastrointestinal-related ADR (20.3%) and endocrine system-related ADR (16.3%). Most of these events had recovered or were in remission by the last evaluation. The median OS was 7.52 months (95% confidence interval, 6.47-8.74). Median OS was 6.31 and 8.44 months in patients with mucosal melanoma and melanoma of the skin; 9.43 and 3.75 months in patients with and without ADR; and 10.32 and 6.11 months in patients with and without serious ADR, respectively. Ipilimumab was tolerable and showed efficacy in improving OS for these patients.

Japanese real-world study of sequential nivolumab and ipilimumab treament in melanoma.

To describe the treatment patterns of nivolumab and ipilimumab in Japan, a retrospective observational study was conducted in melanoma patients who received nivolumab and ipilimumab sequentially. Patients who received nivolumab and ipilimumab in combination were excluded from this study. Efficacy was evaluated by the Response Evaluation Criteria in Solid Tumors (RECIST) in terms of the overall response rate (ORR), progression-free survival (PFS), and disease control rate (DCR). Overall survival (OS) was also evaluated. Safety was assessed by the Common Terminology Criteria for Adverse Events (CTCAE). The treatment for all 68 patients enrolled involved switching from nivolumab to ipilimumab in 61 patients and switching from ipilimumab to nivolumab in seven patients. Switching occurred because of progressive disease in 55 patients and adverse events in eight patients. The median number of ipilimumab doses was three. Ipilimumab treatment achieved an ORR and DCR of 4.9% and 21.3%, respectively, and the median OS from start of ipilimumab was 7.0 months. During the study period, no new safety signals were noted. Independent factors which were indicative of poor prognosis for PFS were high neutrophil-to-lymphocyte ratio (NLR) and high C-reactive protein (CRP) levels before ipilimumab treatment. An evaluation over a washout period indicated that no significant relationship existed with efficacy or safety. For the sequential administration of nivolumab and ipilimumab in Japanese melanoma patients, switch from nivolumab to ipilimumab was common, and the major reason for switching was progressive disease. The major prognostic factors for ipilimumab PFS after nivolumab were NLR and CRP before ipilimumab treatment.

[Efficacy and Management of Adverse Events of Ipilimumab Including Combination Therapy with Nivolumab].

The treatment of cancer has been greatly improved in recent years by immune checkpoint inhibitors. Anti-CTLA-4 and anti- PD-1 antibodies, two types of immune checkpoint inhibitors, have great potential to prolong survival, while they have different characteristics of efficacy and safety profiles. Combination therapy with the anti-CTLA-4 antibody ipilimumab and the anti-PD-1 antibody nivolumab has better efficacy than monotherapy. On the other hand, immune checkpoint inhibitors can result in a wide variety of immune-related adverse events(irAEs), which should be carefully managed. Such irAE includes that of the gastrointestinal tract, liver, and endocrine system, and is increased in incidence and severity when combined with ipilimumab and nivolumab. It is known that clinical characteristics of irAEs are different from those of typical autoimmune diseases. Therefore, irAEs should be managed in line with the algorithms and the appropriate use guides specifically for these drugs.

Is sentinel node susceptibility to metastases related to nodal immune modulation?

Sentinel lymph nodes (SLNs), the initial site of regional metastases, directly receive lymph containing immune-modulatory cytokines and tumor cells from primary melanomas. Immune-suppressed SLNs are ideal for studies of tissue susceptibility to metastases. They show reduced antigen-presenting dendritic cells, activated T cells, high endothelial venules, and transvenular immigration of T cells. Tumor-induced immune suppression contributes to establishment of nodal metastases. SLNs may serve as an effective model to study reversal of tumor-induced immune suppression. We reviewed this topic in Nature Reviews of Immunology in 2006. We here summarize the Nature paper and provide additional results from ongoing studies and the recent literature.

"Stealth" melanoma cells in histology-negative sentinel lymph nodes.

A proportion of patients who develop regional and distant recurrences of melanoma after a pathologically negative sentinel lymph node (SN) biopsy are reported to have enhanced signals for melanoma-associated messenger ribonucleic acid (mRNA) when sensitive molecular approaches such as reverse transcriptase polymerase chain reaction (RT-PCR) are used to evaluate their SN tissue. The significance of these findings remains controversial, because the cellular source of the augmented signals cannot be known as the nodal tissue is destroyed during preparation for RT-PCR. Nevertheless, it is claimed that the source of the augmented signal is covert metastatic melanoma cells. To determine whether there are histologically occult metastases in SN and whether there are sources of augmentable melanoma-associated mRNA other than melanoma cells, we applied reverse transcriptase in situ polymerase chain reaction (RT in situ PCR) to formalin-fixed paraffin-embedded nodal tissue. This approach amplifies small amounts of melanoma-associated mRNA and permits identification of cells that express that mRNA. Cells containing MART-1 mRNA were detected in 6 of 21 SNs (29%) and 2 of 16 nonsentinel lymph node (NSNs) (13%) that were tumor negative on hematoxylin and eosin and on immunohistochemical assessment for S-100, MART-1, and HMB-45. In patients with microscopic evidence of melanoma in their SN, MART-1 mRNA-positive cells were identified in 2 of 7 NSNs (29%) that were histologically tumor free. MART-1 mRNA-positive cells were also detected in tumor-negative SN sections from 6 of 7 (86%) nodes that had tumor present in areas of the node not represented in the studied sections. Some cells that expressed MART-1 mRNA that was diffusely distributed in the cytoplasm appeared to be melanoma cells, whereas others resembled macrophages. The latter cells expressed augmented mRNA on granules that were intermixed with melanin granules. In other cases, MART-1 mRNA-positive macrophage-like cells contained nuclei and nucleoli more typical of melanoma cells and may represent the macrophage-melanoma hybrids that have been previously reported. Combination of RT in situ PCR for MART-1 mRNA and immunohistochemistry for CD68 revealed that CD68 was colocalized in some cells that expressed MART-1 mRNA. Some lymph nodes that are tumor negative by histology and immunohistochemistry contain cells that express mRNA for MART-1. Some of these cells may be interpreted as "stealth" melanoma cells in which, despite the presence of MART-1 mRNA, there is an absence of immunohistochemically detectable MART-1 protein. Other cells that contain MART-1 mRNA are clearly not melanoma cells or may represent melanoma hybrids. These findings should be taken into account when interpreting and applying the results of RT-PCR analysis of nodal (and other) tissues.

Clinically relevant information from sentinel lymph node biopsies of melanoma patients.

Careful laboratory evaluation of sentinel nodes (SNs) is critical to determine the presence of tumor. This requires evaluation of multiple full-face sections from the SN, using H&E staining and immunohistochemistry. In the future, molecular and genetic approaches may be adjunctive to microscopy. Number of tumor-positive SNs and the amount and location of tumor in SNs correlate with tumor spread to non-sentinel nodes, subsequent recurrences and melanoma death, permitting patient assignment to a risk category.

IL-10 expression by primary tumor cells correlates with melanoma progression from radial to vertical growth phase and development of metastatic competence.

Downregulation of the immune system facilitates tumor progression at different stages of cutaneous melanoma. Sentinel nodes, the first lymph nodes on lymphatics draining directly from a primary melanoma, are immune downregulated by tumor-generated immunosuppressive cytokines, including interleukin-10 (IL-10). To better understand the kinetics of sentinel node suppression, we investigated IL-10 expression by melanoma cells and tumor-associated macrophages and lymphocytes at different stages of primary melanoma evolution. We used reverse-transcriptase in situ PCR to identify the cellular sources of IL-10 mRNA in 39 melanomas. IL-10 mRNA was identified in tumor cells of 2 of 6 melanomas in situ (33%), of 17 of 21 invasive melanomas (81%) and of 11 of 12 metastatic melanomas (92%). Higher IL-10 expression correlates with tumor progression, with differences between melanoma in situ, invasive melanoma and metastatic melanoma. In primary melanomas, the IL-10 mRNA content of tumor cells correlates with Clark's level. There was significantly more IL-10 mRNA in vertical growth-phase melanoma cells than in radial growth-phase cells. In a logistic regression model, moderate-to-high IL-10 mRNA expression by tumor cells was significantly associated with vertical growth-phase melanoma. IL-10 mRNA was detected in melanoma-associated macrophages and lymphocytes. In invasive melanomas, IL-10 mRNA reactivity of macrophages decreased as Clark's level increased. Alterations of immunity by IL-10 derived from melanoma cells and melanoma-associated macrophages and lymphocytes potentially facilitate evolution of the primary melanoma and render regional lymph nodes susceptible to metastases.

VEGF-C and VEGFR-3 in a series of lymphangiomas: is superficial lymphangioma a true lymphangioma?

Lymphangiomas are commonly regarded as vascular malformations during embryonic development rather than as true neoplasms. VEGF-C and VEGFR-3 are known to be active in the formation of lymphangiomas. However, the significance of the disorders seems to be obscured by confusing different entities. In 114 lymphangiomas, we investigated the clinicopathological features and the expression of VEGF-C and VEGFR-3. The age of patients with lymphangioma circumscriptum or intraabdominal lymphangioma was significantly higher than in patients with cavernous lymphangioma and in patients with cystic hygroma. In cavernous lymphangioma, the age of female patients was significantly higher than in male patients. Five adult cystic hygromas were identified. VEGF-C was detected in 21 of 58 (36%) cavernous lymphangiomas, ten of 28 (36%) cystic hygromas, 0 of 12 (0%) lymphangioma circumscriptum, and four of ten (40%) intraabdominal lymphangiomas. VEGFR-3 was detected in 43 of 58 (72%) cavernous lymphangiomas, 20 of 28 (71%) cystic hygromas, six of 12 (50%) lymphangiomas circumscriptum, and seven of ten (70%) intraabdominal lymphangiomas. VEGF-C was absent from superficial lymphangiomas associated with cavernous lymphangiomas. In typical cases of cavernous lymphangioma, VEGF-C was strongly expressed, suggesting that these cases possessed proliferative activity. In cystic hygroma and intraabdominal lymphangioma, VEGF-C was limited in its distribution. Superficial lymphangiomas more likely represent from peripheral lymphatic dilatation rather than due to growth factor.

RT in situ PCR detection of MART-1 and TRP-2 mRNA in formalin-fixed, paraffin-embedded tissues of melanoma and nevi.

Melanoma antigen recognized by T cells 1 (MART-1) and tyrosinase-related protein-2 (TRP-2) are two useful markers for immunohistochemical detection of melanocytic tumors. However, these markers may be passively acquired (phagocytosed) rather than actively synthesized. Reverse transcriptase in situ polymerase chain reaction (RT in situ PCR) can amplify even small amounts of specific mRNA in cells and therefore confirm the cellular source of a marker. We developed a one-step RT in situ PCR procedure in which Thermus thermophilus DNA polymerase synthesizes and amplifies cDNA from mRNA in a single reaction mixture. To examine its practicability and feasibility with formalin-fixed, paraffin-embedded (FFPE) tissue, we compared the results of one-step RT in situ PCR with those of immunohistochemistry (IHC). MART-1 mRNA was identified in the cytoplasm of lesional cells from 23/26 primary melanomas (92%), 9/9 metastatic melanomas (100%) and 5/6 nevi (83%). MART-1 epitope was detected by IHC in 23/24 primary melanomas (96%), 9/9 metastatic melanomas (100%) and 5/6 nevi (83%). TRP-2 mRNA was identified in the cytoplasm of lesional cells from 17/26 primary melanomas (65%), 6/9 metastatic melanomas (67%) and 4/6 nevi (67%). TRP-2 epitope was detected by IHC in 20/24 primary melanomas (83%), 9/9 metastatic melanomas (100%) and 4/6 nevi (67%). Both techniques detected MART-1 and TRP-2 in FFPE melanoma cell lines. Neither marker was detected in squamous cell carcinomas or basal cell carcinomas by RT in situ PCR or IHC. We conclude that the RT in situ PCR technique can be successfully applied to FFPE tissue to determine the cellular sources of gene expression observed by conventional PCR approaches.

Detection and characterization of vascular endothelial growth factors and their receptors in a series of angiosarcomas.

BACKGROUND: Angiosarcomas are malignant mesenchymal neoplasms, including sarcomas of presumptive vascular endothelial origin and sarcomas of probable lymphatic origin. It is, however, often difficult to determine whether they are from blood vascular or lymphatic endothelium. The majority of angiosarcomas are thought to originate from vascular endothelia and spread via bloodstream to lung, but lymphatic metastases can occur. METHODS: We investigated immunohistochemical expression of vascular endothelial growth factors (VEGF-A, VEGF-C) and their receptors (VEGFR-1, VEGFR-2, VEGFR-3) in a series of 34 angiosarcomas. RESULTS: VEGF-A was expressed by 32/34 (94%), VEGF-C by 4/34 (12%), VEGFR-1 by 32/34 (94%), VEGFR-2 by 22/34 (65%), and VEGFR-3 by 27/34 (79%). Patients who expressed low or no VEGFR-2 showed a significantly unfavorable prognosis by log-rank test (P = 0.010) and multivariate analysis (hazard ratio, 5.16; 95% CI, 1.40-19.04; P = 0.014). VEGFR-1 and VEGFR-3 were not significantly associated with patients' prognosis. CONCLUSIONS: VEGF-A and VEGFR-1 were detected in diverse subtypes of angiosarcomas. In cooperation, VEGF-A and VEGF-C are likely to be involved in the development of angiosarcoma associated with lymphedema. VEGF-C expression may cause susceptibility to lymphatic metastasis through tumor lymphangiogenesis. Angiosarcoma of the scalp, which is traditionally considered as a true hemangiosarcoma, may include some cases of lymphatic origin.

Tumour-induced immune modulation of sentinel lymph nodes.

Sentinel lymph nodes (SLNs), being the first nodes to receive lymph from a primary tumour and the preferential site of initial tumour metastases, are intensively exposed to the bioactive products of tumour cells and other associated cells. This makes them ideal for studies of the factors that determine selective tissue susceptibility to metastases. We postulate that tumour-induced immune modulation of SLNs facilitates lymph-node metastases by inhibiting the generation of tumour-specific cytotoxic T cells that are active against tumour cells of primary and metastatic melanomas. Immune modulation of the lymph nodes can be reversed by granulocyte/macrophage colony-stimulating factor (GM-CSF), a finding that has implications for the future therapy of lymph-node metastases.

Update on lymphatic mapping and sentinel node biopsy in the management of patients with melanocytic tumours.

AIMS: To communicate best practices for sentinel lymph node evaluation and assessment of prognosis for patients with melanoma. METHODS: Description and justification of approaches derive from experience with management of more than 2000 melanoma patients evaluated by lymphatic mapping and sentinel node biopsy (LMSNB). RESULTS: Pathologists, by detecting blue dye or carbon particles or alterations in nodal cell populations should attempt to confirm that a node submitted as sentinel is truly sentinel. Pathologists must adequately sample the node by examining multiple tissue sections and determine the presence or absence of metastatic melanoma using sections stained by H&E and immunocytochemistry. Approximately 20% of patients have melanoma in the sentinel node (SN) and accurate evaluation of SN tumour status is the most precise technique for staging clinically localised cutaneous melanoma. The remaining non-sentinel nodes (NSN) in the basin are tumour-free in 67% of patients with melanoma in the SN. Breslow thickness of the primary, the area of tumour in the SN (relative to total nodal area) and density of dendritic leukocytes in the SN paracortex (factors that are combinable in prognostic algorithms) predict metastases in the NSN and the likelihood of recurrence and melanoma-specific death. CONCLUSIONS: Careful pathological analysis is essential to determine the presence or absence of metastatic melanoma in sentinel nodes, findings that indicate whether completion lymphadenectomy is required. Quantitative analysis of the primary melanoma and the amount of tumour in the sentinel node, with evaluation of the dendritic cells in that node, provide invaluable information that predicts non-sentinel node tumour status with increased accuracy and the likelihood of future recurrence and death from melanoma. While these activities require considerable effort from pathologists, their clinical impact justifies the increased workload.

Optimized assessment of sentinel lymph nodes for metastatic melanoma: implications for regional surgery and overall treatment planning.

Correct identification of the sentinel node (SN) and accurate evaluation of this node's tumor status constitute the most precise technique for staging clinically localized cutaneous melanoma. However, even if tumor is present in the SN (as in approximately 20% of patients), the remaining nodes in the basin are often tumor-free. We have found that the Breslow thickness of the primary, the relative area of tumor in the SN (with respect to the area of the SN), and the density of dendritic leukocytes in the SN paracortex not only can predict the likelihood of nonsentinel node metastases but also are correlated with likelihood of tumor recurrence and melanoma-specific survival. The most robust of these predictors is relative tumor area, and this may be used as the basis of practical predictive algorithms.

Detection of multiple melanoma-associated markers in melanoma cell lines by RT in situ PCR.

New surgical oncology techniques, such as lymphatic mapping and sentinel node biopsy, require precise identification of the presence of even very small numbers of tumor cells. The gold standard for such analysis remains microscopic assessment of tissue sections, stained conventionally or by immunohistochemistry for appropriate tumor markers. This approach is limited by sampling constraints and requires a high degree of expertise from the microscopist. Recent studies have demonstrated a subgroup of patients whose sentinel nodes are negative on microscopy, but whose nodes yield an enhanced signal for melanoma markers when evaluated by RT-PCR. These enhanced signals reflect a mixture of signal sources, including small numbers of melanoma cells and cells other than melanoma cells that express the relevant markers(s). Because the preparative techniques for RT-PCR destroy the structural integrity of the tissues and disrupt individual cells, the exact cellular source of enhanced signal from a tissue cannot be demonstrated by conventional RT-PCR. RT in situ PCR, in which the RT-PCR technique is applied on a tissue section, does identify the cells that are the source of signal. We have attempted to optimize this interesting approach and have applied it to the detection of relevant melanoma markers in tissue culture lines.

Mutation analysis of human cytokeratin 8 gene in malignant rhabdoid tumor: a possible association with intracytoplasmic inclusion body formation.

The rhabdoid cell, which is typically observed in malignant rhabdoid tumor (MRT) and other malignant neoplasms, has an eosinophilic cytoplasm containing a spheroid perinuclear inclusion body. This distinct cell is known to act as a highly aggressive indicator in many types of malignant tumors and is characterized by aggregates of intermediate filaments, comprising both vimentin and cytokeratin (CK) 8, which is mainly expressed in simple-type epithelium such as liver and intestine. To clarify the cause of the inclusion body formation, we analyzed the alteration of the complete human CK8 gene (KRT 8: 1724 base pairs) in seven samples of MRT (three from frozen materials and four from cultured cell lines) by reverse-transcriptase polymerase chain reaction, followed by direct sequencing. In addition, the two cell lines, Huh7 and HeLa, which lacked rhabdoid feature, six pediatric malignant tumors, including three cases of primitive neuroectodermal tumor (PNET) and three of Wilms' tumor; and 15 normal liver tissue (as a control) were also analyzed. All MRT samples had missense mutations in the human KRT 8 gene, i.e., Arg89 --> Cys (5/7); Arg --> Cys251 (3/7); Glu267 --> Lys (6/7); Ser290 --> Ile, Met; (7/7) and Arg301 --> His(4/7), none of which was detected in any control samples. Among these mutations, the most noteworthy findings were that Arg89 belongs to the H1 subdomain of the head domain and that Arg251 belongs to the short nonhelical linker segment, or L1-2. Both these mutations are noted for their relationships to lateral protofilament-protofilament interactions. In addition, Ser290 has been previously reported to be a phosphorylation site, which has been recognized to play an important role in filament organization, leading to conformational change of the CK8 filaments. In conclusion, mutated codons of CK8 gene in MRT were located in the important region involved in the conformational change of intermediate filament.