Monday 20 June 2016

Ocular Melanoma: Randomised phase 2 study of Trametinib +/- GSK2141795 in patients with advanced uveal melanoma

ASCO 2016: Poster Session
Alexander Shoushtari's team have investigated the value of adding an AKT inhibitor (GSK2141795) to the MEK inhibitor drug Trametinib in the expectation that it might mediate against acquired resistance.

Disruption of the MAP kinase pathway (MAPK) has been assoicated with immune response in other tumour types and hence the pursuit of responses with a MEK inhibitor which forms a part of this pathway.

This phase 2 trial concluded that there was no increase in PFS and that objective reponses were rare. Moreover, dose reduction because of side effects were frequent.

Thursday 16 June 2016

Adjuvant therapies for high risk Melanoma - Surgical Management

First speaker (Van Akkooi) discusses the surgical management for high risk melanoma




Wide Local Excision (WLE)




Findings:
  • Haydu (2016): Difference only in Relapse Free Survival (RFS) when pT2 and comparing both arms in table above. No difference in Overall Survival (OS) however.
  • Thomas (2004): Difference in Locoregional recurrence when comparing 1cm to 3 cm WLE (3cm is off course better than 1 cm)
  • Hayes (2016), which is same dataset as Thomas (2004) but now longer follow up: Differences in Melanoma Specific Survival (MSS), again difference in OS is not sigificant




Is Sentinel Node Biopsy (SNB) of therapeutic value, or prognostic value?




According to Van Akkooi, the data supports the claim that SNB Positive (yellow line) and Observation with nodal recurrence (orange) have a significantly different Melanoma-Specific Survival. One could suggest that having a positive SNB is preferential compared to haven't executed a SNB and observe a nodal recurrence later. 


Adjuvant Ipilimumab: 20% relapse free survival benefit for Ipi adjuvant after CLND.






When looking to the Subgroups : positive SN (effect is highest) vs. palpable node
Most effect of Adjuvant Ipi : positive SN with ulcerated primary Melanoma






Van Akkooi is convinced no Complete Lymph Node Dissections (CLND) will be executed in the future unless one relapses. Instead of CLND => Adjuvant Therapy (e.g. Ipi) when Sentinel Node Biopsy positive.










Wednesday 15 June 2016

Combinations of PD1 and Targeted Therapy


CTLA-4 blockade/ IPPI 
  • 10 yr overall survival rate
  • 1-3 month duration of treatment 
  • 20-30% immune related toxicity 
  • Retreat successful 
  • Absence of predictive bio-marker 
PD1 Blockade 
  • 3-5 yr Overall survival rate
  • Superior OS to IPPI 
  • DCR >50% Better Kinetics 
  • Low immune related Toxicity 
  • Up to 2 years continuous treatment 
  • Retreat Appears Successful 
  • PDL-1 Biomarker Sub Optimal 
Combined CTLA-4 and PD-1 have given results as follows 
  • 2-3 years overall survival 60-70%
  • 50% PFS plateau at 2 years 
  • 1-6 months of treatment rapid Kinetics 
  • 50-60% immune related toxicity 
  • Retreatment success is unknown 
  • PDL-1 marker encouraging 
In the combined treatment it has been proven that PD-1 followed by CTLA-4 sequence is Superior with a 1 yr overall response rate of 76% but with higher grade 3-4  Toxicity in 63%
But early treatment discontinuation does not effect efficacy so the question remains are patients being over treated?

A new era in of immunotherapy by combining therapies means 50% long term survival a reality toxicity management remains crucial and requires teamwork and experience. Toxicity can shorten duration of treatment but does not impare survival! 

The data overall survival rates with Dabrafenib/ Trametnib Combi-d are as follows
3 yrs OS 25% with elevated LDH levels and PFS 13%
3yrs OS 54% with normal LDH levels and PFS 27%
Presentation by Dr Keith Flaherty

Pembro  + IPPi  (Keynote 029) phase 1 153 patients treated
Pembro 2mg in combination with 4 doses of  IPPI 1mg has a manageable toxicity and provides robust anti-tumour activity
ORR was 57%
70% progression free at 6 months at data cut off point
Presentation by  Dr Georgina Long


There is a phase 2 study of Dabrafenib/Trametnib and Pembro combined (Keynote 022)
Recruitment is ongoing 

Ocular Melanoma: Disparity in PD-L1 expression between metastatic uveal and cutaneous melanoma

ASCO 2016: Poster Session 146
This study examined the presence of the PD-L1 ligand on both cutenous and uveal metastic tumours. PD-L1 expression has been considered as a possible biomarker to determine the likely efficacy of immune-modulatory drugs, although questions still remain as to its prognostic value and also what might acurately be considered a threshold value to indicate its presence.

In ocular melanoma however, PD-L1 is virtually non-existent in the metastatic setting and the authors suggest that this may explain the lower of response from drugs such as Pembrolizumab or Nivolumab.

Ocular Melanoma: Prognosticators of first line treatment of metastatic uveal melanoma (MUM)

ASCO 2016: Poster Session 175
A retrospective study, gathering data from previous UM cases including trial data, aiming to establish the best predictors of survival in the metastatic setting. Such tests exist for the primary melanoma but none as yet for metastatic patients.

Unsurprisingly liver burden was key in predicting overall response and affects the viability of both surgical interventions and the efficacy of systemic approaches. Identifying the need for additional therapeutic approaches was concluded, although this might be mitigated by the fact that some of the patients from 2004-2012 would have likely missed out on an immunotherapy or new liver directed treatments.

Interstingly, the survival graph is plotted from diagnosis of metastic disease as opposed to post initial treatment. This is different from the usual curves we see for performance of immuntherapy drugs, say, which measure from time of first infusion.

Ocular Melanoma: The identification of novel genetic risk loci in uveal melanoma

ASCO 2016: Poster Session 366
Using blood tests to determine whether it is possible to more accurately determine risk of uveal melanoma. This may have uses in familial, or germline, mutations where particular markers can be associated with increased likelihood of disease occurence.

Saturday 11 June 2016

Multidisciplinary Management of Brain Metasteses

The session on Brain Metastases was not specifically melanoma but general Brain Mets studies - 

The brain is an immune privileged organ so there is a restrictive influence of the immune response which makes it harder to treat. They have recently discovered some kind of fluid transfer system but it lacks the normal lymphoid structure so antigen presentation and T-Cell infiltration is less well understood. Melanoma has more CD3+ and CD8+ TIL Density in Melanoma BMs and more FOXP3 TIL. The role of Microglial Macrophages (these are the main macrophages in Brain tissue and are the main form of active immune defence in the brain and central nervous system) in BMs is complicated : they are both tumour-promoting and tumour-suppressing depending on where in the metastatic cascade they are - brain tumour cells seem to co-opt them in some way - does inhibiting microglia reduce BM cell invasion ?



The Biology of Brain Mets : 

A couple of nice slides of the Venue of action of Checkpoint Inhibitors in BMs : 





And a summary :



(http://meetinglibrary.asco.org/content/50918?media=vm)

One Melanoma Abstract - 

Abstract 2071 - The retrospective analysis of Brain mets in Melanoma by the Boston team did show clinical activity on Brain Mets by Pembrolizumab - there is an ongoing study of patients with untreated BMs : NCT02085070

One Poster presentation :

Poster : Another retrospective study on the effect of Pembro using real world data from the french MELBASE registry - POSTER - the results were not that conclusive because results were complicated by radiotherapy treatment and pretreatment with Ipilimumab before  Pembrolizumab - but overall they concluded that Pembrolizumab PROBABLY better than Ipilimumab in Melanoma Brain Mets - apart from testing how to use registry data - there is not much we can take from this.
 Use of SRS  in treating BMs - Is there a role for Whole Brain Radiation ?
The initial treatment of most patients with limited brain metastases is stereotactic radiosurgery (SRS). SRS is a type of radiotherapy that aims beams precisely at the area of the brain tumor. After SRS, some patients also receive adjuvant whole-brain radiation therapy (WBRT).
The use of WBRT in patients with limited brain metastases has been controversial. Although WBRT does control tumor growth, it can have detrimental effects on quality of life. Preliminary findings from a federally funded study (NIH) have provided new insights into the impact of adjuvant WBRT on cognition 
Patients with one to three small brain metastases who received WBRT after SRS were more likely to experience cognitive decline within the first 3 months than those who received SRS alone. Specifically, those who received WBRT had a greater decline in memory and verbal communication. There was no significant survival benefit from WBRT, compared with SRS alone.
The results strongly suggest it may be preferable to forgo WBRT in favor of SRS, because SRS can preserve a patient’s cognitive function as long as possible. Longer-term follow-up to assess late neurocognitive effects of WBRT is pending.
Nonetheless, WBRT decreases recurrence of brain metastases, and it is possible that it may prolong survival in certain patients. A smaller Japanese study identified one such patient group. Patients with NSCLC who had one to four brain metastases and a favorable prognosis lived 6 months longer when treated with SRS and WBRT compared with SRS alone. No such survival advantage was observed among patients with a poor prognosis. Larger prospective studies are needed to confirm these findings.

A few slides on Adjuvant WBRT - basically dont do it ...




and is there ANY place for WBRT  :



From Melanoma perspective : this is 2015 but a useful summary :