Pembrolizumab use for the treatment of advanced melanoma

Improving care of melanoma patients through efficient, integrated cellular-molecular pathology workflows using tissue samples with low tumour nuclear content

AIMS

The aim of this quality improvement project was to improve the turnaround time of B-raf proto-oncogene (BRAF) mutation testing in patients with malignant melanoma to support oncologists in making timely treatment decisions.

METHODS

This is a prospective in-house verification of the Idylla BRAF test as compared with DNA panel next-generation sequencing (NGS) performed at an external laboratory.

RESULTS

The Idylla BRAF test had an overall concordance of 95% compared with NGS. This was considered sufficiently good for use in patients with a poor performance status who were at risk of rapid clinical deterioration. Reliable results can be generated using the Idylla BRAF test in tissue sections with tumour neoplastic cell content below 50%. We present a multidisciplinary clinical care algorithm to support dual testing.

CONCLUSIONS

The Idylla BRAF test has the potential to make a significant positive impact on progression-free survival of malignant melanoma patients due to its rapid turnaround time. The Idylla BRAF test can be used as an adjunct to NGS for timely management of patients, particularly those with a poor performance status at presentation.

Pivotal role of PD-1/PD-L1 immune checkpoints in immune escape and cancer progression: Their interplay with platelets and FOXP3+Tregs related molecules, clinical implications and combinational potential with phytochemicals

Immune checkpoint proteins including programmed cell death protein 1 (PD-1), its ligand PD-L1 and cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) are involved in proliferation, angiogenesis, metastasis, chemoresistance via immune escape and immune tolerance by disturbing cytotoxic T cell activation. Though many clinical trials have been completed in several cancers by using immune checkpoint inhibitors alone or in combination with other agents to date, recently multi-target therapy is considered more attractive than monotherapy, since immune checkpoint proteins work with other components such as surrounding blood vessels, dendritic cells, fibroblasts, macrophages, platelets and extracellular matrix within tumor microenvironment. Thus, in the current review, we look back on research history of immune checkpoint proteins and discuss their associations with platelets or tumor cell induced platelet aggregation (TCIPA) and FOXP3+ regulatory T cells (Tregs) related molecules involved in immune evasion and tumor progression, clinical implications of completed trial results and signaling networks by phytochemicals for combination therapy with immune checkpoint inhibitors and suggest future research perspectives.

Combination PD-1 blockade and irradiation of brain metastasis induces an effective abscopal effect in melanoma

Nearly half of melanoma patients develop brain metastases during the course of their disease. Despite advances in both localized radiation and systemic immunotherapy, brain metastases remain difficult to treat, with most patients surviving less than 5 months from the time of diagnosis. While both treatment regimens have individually shown considerable promise in treating metastatic melanoma, there is interest in combining these strategies to take advantage of potential synergy. In order to study the ability of local radiation and anti-PD-1 immunotherapy to induce beneficial anti-tumor immune responses against distant, unirradiated tumors, we used two mouse models of metastatic melanoma in the brain, representing BRAF mutant and non-mutant tumors. Combination treatments produced a stronger systemic anti-tumor immune response than either treatment alone. This resulted in reduced tumor growth and larger numbers of activated, cytotoxic CD8⁺ T cells, even in the unirradiated tumor, indicative of an abscopal effect. The immune-mediated effects were present regardless of BRAF status. These data suggest that irradiation of brain metastases and anti-PD-1 immunotherapy together can induce abscopal anti-tumor responses that control both local and distant disease.

SD-101 in Combination with Pembrolizumab in Advanced Melanoma: Results of a Phase Ib, Multicenter Study

PD-1 inhibitors are approved for treating advanced melanoma, but resistance has been observed. This phase Ib trial evaluated intratumoral SD-101, a synthetic CpG oligonucleotide that stimulates Toll-like receptor 9 (TLR9), in combination with pembrolizumab in patients with unresectable or metastatic malignant melanoma. The most common adverse events related to SD-101 were injection-site reactions and transient, mild-to-moderate "flu-like" symptoms. Among the 9 patients naïve to anti-PD-1 therapy, the overall response rate (ORR) was 78%. The estimated 12-month progression-free survival rate was 88%, and the overall survival rate was 89%. Among 13 patients having prior anti-PD-1 therapy, the ORR was 15%. RNA profiling of tumor biopsies demonstrated increased CD8⁺ T cells, natural killer cells, cytotoxic cells, dendritic cells, and B cells. The combination of intratumoral SD-101 and pembrolizumab was well tolerated and induced broad immune activation in the tumor microenvironment with durable tumor responses in both peripheral and visceral lesions.Significance: These early data demonstrate that the combination of pembrolizumab with intratumoral SD-101 is well tolerated and can induce immune activation at the tumor site. Combining an intratumoral TLR9 innate immune stimulant with PD-1 blockade can potentially increase clinical efficacy with minimal additional toxicity relative to PD-1 blockade alone. Cancer Discov; 8(10); 1250-7. ©2018 AACR. This article is highlighted in the In This Issue feature, p. 1195.

Irradiation enhanced the effects of PD-1 blockade in brain metastatic osteosarcoma

Brain metastasis of osteosarcoma are rare but carry a dismal prognosis. Despite the advances in both systemic immunotherapy and localized radiation, it is still difficult to treat brain metastasis, with less than 12 months of survival from the time of diagnosis for most patients. Currently, there is interest in combining strategies to take advantage of the potential synergy. In this study, the mouse model of metastatic osteosarcoma to brain was used to explore the ability of local radiation and anti-PD-1 blockade to induce beneficial anti-tumor immune responses against distant, unirradiated brain metastatic tumors. Immune markers from the peripheral blood and tumor tissue were analyzed by flow cytometry, real-time PCR and western blot. The combination treatment produced a stronger systemic anti-tumor response than either treatment alone, shown by the reduced tumor burden and larger numbers of cytotoxic CD8⁺ T cells in the unirradiated tumors, indicating an abscopal effect. These data suggested that combination treatment of irradiation with anti-PD-1 immunotherapy can induce abscopal anti-tumor responses and improve both local and distant control.

Isolated Limb Infusion: A Single-Center Experience with Over 200 Infusions

BACKGROUND

Isolated limb infusion (ILI) is a minimally invasive technique for delivering regional chemotherapy to an extremity for patients with locally advanced cutaneous malignancies and sarcoma.

METHODS

A single-institution, prospectively collected database was analyzed for intention-to-treat with ILI.

RESULTS

From 2007 to 2016, 163 patients underwent 205 procedures (201 were successfully completed), and four malignancies were treated: melanoma (72.1% of all ILIs), sarcoma (23.4%), squamous cell carcinoma (SCC; 2.0%) and Merkel cell carcinoma (MCC; 2.5%). A median grade II regional Wieberdink toxicity score was observed, with 88.1% of patients experiencing grade II or less. Median follow-up was 21.8 months, and overall response rate (ORR) was 59.0% for melanoma, 48.9% for sarcoma, 50.0% for SCC, and 60.0% for MCC. A significant difference (p = 0.04) between upper (76.9%) and lower extremity (55.1%) ORR was observed in patients with melanoma. When comparing responders with nonresponders, patients with melanoma had significantly longer in-field progression-free survival (IPFS; 14.1 vs. 3.2 months, p < 0.001), distant metastatic-free survival (DMFS; not reached vs. 25.8 months, p = 0.006), and overall survival (OS; 56.0 vs. 26.7 months, p = 0.0004). Sarcoma responders had a significantly longer IPFS (13.0 vs. 2.7 months, p < 0.0001), but no significant distant metastatic or OS advantage. Over a median follow-up of 19.3 months, sarcoma patients had an overall limb salvage rate of 68.4%.

CONCLUSION

ILI is a well-tolerated procedure for patients with locally advanced melanoma, sarcoma, and other cutaneous malignancies. ILI responders had a significantly longer time to IPFS, while melanoma responders also had a DMFS and OS advantage.

Uveal Melanoma: Identifying Immunological and Chemotherapeutic Targets to Treat Metastases

Uveal melanoma is an intraocular malignancy that, depending on its size and genetic make-up, may lead to metastases in up to 50% of cases. Currently, no therapy has been proven to improve survival. However, new therapies exploiting immune responses against metastases are being developed. The primary tumor is well characterized: tumors at high risk of developing metastases often contain macrophages and lymphocytes. However, these lymphocytes are often regulatory T cells that may suppress immune response. Currently, immune checkpoint inhibitors have shown marked efficacy in multiple cancers (eg, cutaneous melanoma) but do not yet improve survival in uveal melanoma patients. More knowledge needs to be acquired regarding the function of T cells in uveal melanoma. Other therapeutic options are related to the biochemical pathways. Targeting the RAF-MEK-ERK pathway with small molecule MEK inhibitors abrogates the growth of UM cells harboring GNAQ/GNA11 Q209 mutations, suggesting that these aberrant G-protein oncogenes mediate, at least in part, their effect through this hallmark proliferation pathway. Other pathways are also implicated, such as those involving c-Jun and YAP. Further studies may show how interference in the different pathways may affect survival.