Combined Nivolumab and Ipilimumab in Octogenarian and Nonagenarian Melanoma Patients

Data regarding elderly melanoma patients treated with anti-PD-1 or anti-CTLA-4 antibodies are in favor of tolerability outcomes that are similar to those of younger counterparts. However, there are very few studies focusing on elderly patients receiving nivolumab combined with ipilimumab (NIVO + IPI). Here, we ask what are the current prescribing patterns of NIVO + IPI in the very elderly population and analyze the tolerance profile. This French multicenter retrospective study was conducted on 60 melanoma patients aged 80 years and older treated with NIVO + IPI between January 2011 and June 2022. The mean age at first NIVO + IPI administration was 83.7 years (range: 79.3-93.3 years). Fifty-five patients (92%) were in good general condition and lived at home. Two dosing regimens were used: NIVO 1 mg/kg + IPI 3 mg/kg Q3W (NIVO1 + IPI3) in 27 patients (45%) and NIVO 3 mg/kg + IPI 1 mg/kg Q3W (NIVO3 + IPI1) in 33 patients (55%). NIVO + IPI was a first-line treatment in 39 patients (65%). The global prevalence of immune-related adverse events was 63% (38/60), with 27% (16/60) being of grade 3 or higher. Grade ≥ 3 adverse events were less frequent in patients treated with NIVO3 + IPI1 compared with those treated with NIVO1 + IPI3 (12% versus 44%, p = 0.04). In conclusion, the prescribing patterns of NIVO + IPI in very elderly patients are heterogeneous in terms of the dosing regimen and line of treatment. The safety profile of NIVO + IPI is reassuring; whether or not the low-dose regimen NIVO3 + IPI1 should be preferred over NIVO1 + IPI3 in patients aged 80 years or older remains an open question.

Cardiomuscular Biomarkers in the Diagnosis and Prognostication of Immune Checkpoint Inhibitor Myocarditis

BACKGROUND

Immune checkpoint inhibitors (ICIs) are approved for multiple cancers but can result in ICI-associated myocarditis, an infrequent but life-threatening condition. Elevations in cardiac biomarkers, specifically troponin-I (cTnI), troponin-T (cTnT), and creatine kinase (CK), are used for diagnosis. However, the association between temporal elevations of these biomarkers with disease trajectory and outcomes has not been established.

METHODS

We analyzed the diagnostic accuracy and prognostic performances of cTnI, cTnT, and CK in patients with ICI myocarditis (n=60) through 1-year follow-up in 2 cardio-oncology units (APHP Sorbonne, Paris, France and Heidelberg, Germany). A total of 1751 (1 cTnT assay type), 920 (4 cTnI assay types), and 1191 CK sampling time points were available. Major adverse cardiomyotoxic events (MACE) were defined as heart failure, ventricular arrhythmia, atrioventricular or sinus block requiring pacemaker, respiratory muscle failure requiring mechanical ventilation, and sudden cardiac death. Diagnostic performance of cTnI and cTnT was also assessed in an international ICI myocarditis registry.

RESULTS

Within 72 hours of admission, cTnT, cTnI, and CK were increased compared with upper reference limits (URLs) in 56 of 57 (98%), 37 of 42 ([88%] P=0.03 versus cTnT), and 43 of 57 ([75%] P<0.001 versus cTnT), respectively. This increased rate of positivity for cTnT (93%) versus cTnI ([64%] P<0.001) on admission was confirmed in 87 independent cases from an international registry. In the Franco-German cohort, 24 of 60 (40%) patients developed ≥1 MACE (total, 52; median time to first MACE, 5 [interquartile range, 2-16] days). The highest value of cTnT:URL within the first 72 hours of admission performed best in terms of association with MACE within 90 days (area under the curve, 0.84) than CK:URL (area under the curve, 0.70). A cTnT:URL ≥32 within 72 hours of admission was the best cut-off associated with MACE within 90 days (hazard ratio, 11.1 [95% CI, 3.2-38.0]; P<0.001), after adjustment for age and sex. cTnT was increased in all patients within 72 hours of the first MACE (23 of 23 [100%]), whereas cTnI and CK values were less than the URL in 2 of 19 (11%) and 6 of 22 (27%) of patients (P<0.001), respectively.

CONCLUSIONS

cTnT is associated with MACE and is sensitive for diagnosis and surveillance in patients with ICI myocarditis. A cTnT:URL ratio <32 within 72 hours of diagnosis is associated with a subgroup at low risk for MACE. Potential differences in diagnostic and prognostic performances between cTnT and cTnI as a function of the assays used deserve further evaluation in ICI myocarditis.

Efficacy of Immune Checkpoint Inhibitor (ICI) Rechallenge in Advanced Melanoma Patients' Responders to a First Course of ICI: A Multicenter National Retrospective Study of the French Group of Skin Cancers (Groupe de Cancérologie Cutanée, GCC)

BACKGROUND

The long-term effectiveness of immune checkpoint inhibitor (ICI) rechallenge for progressive or recurrent advanced melanoma following previous disease control induced by ICI has not been thoroughly described in the literature.

PATIENTS AND METHODS

In this retrospective multicenter national real-life study, we enrolled patients who had been rechallenged with an ICI after achieving disease control with a first course of ICI, which was subsequently interrupted. The primary objective was to evaluate tumor response, while the secondary objectives included assessing the safety profile, identifying factors associated with tumor response, and evaluating survival outcomes.

RESULTS

A total of 85 patients from 12 centers were included in the study. These patients had advanced (unresectable stage III or stage IV) melanoma that had been previously treated and controlled with a first course of ICI before undergoing rechallenge with ICI. The rechallenge treatments consisted of pembrolizumab (n = 44, 52%), nivolumab (n = 35, 41%), ipilimumab (n = 2, 2%), or ipilimumab plus nivolumab (n = 4, 5%). The best overall response rate was 54%. The best response was a complete response in 30 patients (35%), a partial response in 16 patients (19%), stable disease in 18 patients (21%) and progressive disease in 21 patients (25%). Twenty-eight adverse events (AEs) were reported in 23 patients (27%), including 18 grade 1-2 AEs in 14 patients (16%) and 10 grade 3-4 AEs in nine patients (11%). The median progression-free survival (PFS) was 21 months, and the median overall survival (OS) was not reached at the time of analysis. Patients who received another systemic treatment (chemotherapy, targeted therapy or clinical trial) between the two courses of ICI had a lower response to rechallenge (p = 0.035) and shorter PFS (p = 0.016).

CONCLUSION

Rechallenging advanced melanoma patients with ICI after previous disease control induced by these inhibitors resulted in high response rates (54%) and disease control (75%). Therefore, ICI rechallenge should be considered as a relevant therapeutic option.

Clostridium difficile infection and immune checkpoint inhibitor-induced colitis in melanoma: 18 cases and a review of the literature

Immunotherapy has become the standard of care for several types of cancer, such as melanoma. However, it can induce toxicity, including immune checkpoint inhibitor-induced colitis (CIC). CIC shares several clinical, histological, biological, and therapeutic features with inflammatory bowel disease (IBD). Clostridium difficile infection (CDI) can complicate the evolution of IBD. We aimed to characterize the association between CDI and CIC in patients treated with anti-CTLA-4 and anti-PD-1 for melanoma. Patients from nine centers treated with anti-CTLA-4 and anti-PD-1 for melanoma and presenting with CDI from 2010 to 2021 were included in this retrospective cohort. The primary endpoint was the occurrence of CIC. The secondary endpoints were findings allowing us to characterize CDI. Eighteen patients were included. Eleven were treated with anti-PD-1, four with anti-CTLA-4, and three with anti-PD-1 in combination with anti-CTLA-4. Among the 18 patients, six had isolated CDI and 12 had CIC and CDI. Among these 12 patients, eight had CIC complicated by CDI, three had concurrent CIC and CDI, and one had CDI followed by CIC. CDI was fulminant in three patients. Endoscopic and histological features did not specifically differentiate CDI from CIC. Nine of 11 patients required immunosuppressive therapy when CDI was associated with CIC. In nine cases, immunotherapy was discontinued due to digestive toxicity. CDI can be isolated or can complicate or reveal CIC. CDI in patients treated with immunotherapy shares many characteristics with CDI complicating IBD. Stool tests for Clostridium difficile should be carried out for all patients with diarrhea who are being treated with immunotherapy.

Efficacy of Large Use of Combined Hypofractionated Radiotherapy in a Cohort of Anti-PD-1 Monotherapy-Treated Melanoma Patients

To assess the role of radiotherapy in anti-PD-1-treated melanoma patients, we studied retrospectively a cohort of 206 consecutive anti-PD-1 monotherapy-treated advanced melanoma patients (59% M1c/d, 50% ≥ 3 metastasis sites, 33% ECOG PS ≥ 1, 33% > 1st line, 32% elevated serum LDH) having widely (49%) received concurrent radiotherapy, with RECIST 1.1 evaluation of radiated and non-radiated lesions. Overall (OS) and progression-free (PFS) survivals were calculated using Kaplan−Meier. Radiotherapy was performed early (39 patients) or after 3 months (61 patients with confirmed anti-PD-1 failure). The first radiotherapy was hypofractionated extracranial radiotherapy to 1−2 targets (26 Gy-4 weekly sessions, 68 patients), intracranial radiosurgery (25 patients), or palliative. Globally, 67 (32.5% [95% CI: 26.1−38.9]) patients achieved complete response (CR), with 25 CR patients having been radiated. In patients failing anti-PD-1, PFS and OS from anti-PD-1 initiation were 16.8 [13.4−26.6] and 37.0 months [24.6−NA], respectively, in radiated patients, and 2.2 [1.5−2.6] and 4.3 months [2.6−7.1], respectively, in non-radiated patients (p < 0.001). Abscopal response was observed in 31.5% of evaluable patients who radiated late. No factors associated with response in radiated patients were found. No unusual adverse event was seen. High-dose radiotherapy may enhance CR rate above the 6−25% reported in anti-PD-1 monotherapy or ipilimumab + nivolumab combo studies in melanoma patients.

Efficacy of immune checkpoint inhibitor (ICI) rechallenge in advanced melanoma patients responders to a first course of ICI: A multicenter, national, retrospective study of the French group of skin cancers (GCC)

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Background: The efficacy of ICI rechallenge for progressive/recurrent disease of advanced melanoma patients (pts) after a first course of ICI interrupted for disease control has not been systematically described. Methods: A retrospective observational multicenter national real-life study evaluated the efficacy and tolerance of ICI rechallenge (anti-PD1, anti-CTLA-4, or combination therapy) in melanoma pts who progressed after disease control with an ICI subsequently interrupted. Primary objective was to evaluate tumor response using RECIST version 1.1. Secondary objectives were the factors associated with tumor response, progression-free survival (PFS), overall survival (OS) and the tolerance of the rechallenge. Results: 85 pts from 12 French different centers rechallenged with an ICI between July 2014 and June 2021 were included. Median (IQR) age of pts was 72.00 (30–89) years. Most pts were male (n = 47, 55%) with an AJCC stage IV melanoma (n = 75, 88%). BRAFV600-mutant melanoma and elevated LDH were reported in 19 pts (22%). Pts were rechallenged with anti-PD1 (Pembrolizumab (n = 44, 52%), Nivolumab (n = 35, 41%)), anti-CTLA-4 (Ipilimumab (n = 2, 2%)) or the combination therapy (Ipilimumab + Nivolumab (n = 4, 5%)). Median follow-up after rechallenge was 13 months (1.1-76.2). All pts included had had disease control with the first course of ICI including complete response (CR) in 47 pts (55%), partial response (PR) in 28 pts (33%) and stable disease (SD) in 10 pts (12%). Adverse events (AEs) of the first course of ICI had occurred in 51% pts including grade 3-4 AEs (22%). Median time between ICI interruption and ICI rechallenge was 9,3 months (1.2-63,9). The response rates of ICI rechallenge (2nd course of ICI) were CR in 30 pts (35%), PR in 17 pts (20%) and SD in 17 pts (20%). Progression occurred in 21 pts (25%). The use of steroids for brain metastases was the only factor associated with a higher recurrence rate in multivariate analysis (p = 0,002) and tends to be associated with lower outcomes. There was no correlation between best overall response to the first course of ICI and response to ICI rechallenge. Median duration of response, PFS and OS after ICI rechallenge were not reached. At last follow-up, 23 pts have died. 28 AEs of ICI rechallenge occurred in 23 pts (27%) with a median time of 3 (0.4-36.2) months, including grade 1-2 and grade 3-4 AEs in 13 (15%) and 9 (11%) pts respectively. Conclusions: ICI rechallenge for progressive/recurrent disease was associated with high objective response rate (CR+PR = 55%) and disease control rate (CR+PR+SD = 75%) in melanoma pts with a previous disease control induced by ICI. Thus, ICI rechallenge should be considered as an attractive therapeutic option for melanoma pts with progressive/recurrent disease after ICI interruption.

Impact du confinement lié au COVID-19 sur le retard au diagnostic et la sévérité du mélanome

Introduction

La pandémie de COVID-19 a eu un fort impact sur la prise en charge des cancers. Plusieurs études ont rapporté une baisse importante du nombre de diagnostics de cancers cutanés durant le confinement de mars 2020 (C), mais peu ont rapporté les conséquences du retard diagnostique sur la sévérité. Notre objectif était d’évaluer l’impact immédiat du C et ses conséquences sur les caractéristiques des mélanomes nouvellement diagnostiqués les mois suivants.

Matériel et méthodes

Étude rétrospective monocentrique, dans un service de Dermatologie en Île-de-France, zone très touchée par la 1ère vague de COVID-19.

Quatre périodes définies :

 – du 17/03/20 au 12/05/20 = confinement (C) ;

 – du 17/03/19 au 12/05/19 = équivalent de la même période l’année précédente (EC) ;

 – du 13/05/20 au 31/10/20 = post-confinement (PC) ;

 – du 13/05/19 au 31/10/19 = équivalent de la même période l’année précédente (EPC).

Tous les patients vus en consultation pour la prise en charge d’un nouveau mélanome pendant ces périodes ont été inclus. Nous avons comparé le nombre de nouveaux cas, les caractéristiques anatomopathologiques et les stades AJCC entre les périodes C vs EC, et PC vs EPC.

Résultats

493 cas consécutifs de mélanome (480 patients, âge moyen 62 ans ± 16, sexe-ratio M/F = 0,96) ont été inclus. Les proportions de mélanomes in situ était similaire dans les 4 groupes. En C vs EC, nous avons observé une baisse de 15,4 % de l’incidence des mélanomes, avec un indice de Breslow significativement plus élevé (2,18 mm ± 2,4 vs 1,63mm ± 2,8, p < 0,001). Les mélanomes incidents en PC étaient plus sévères qu’en EPC avec plus de stades III (13 % vs 6 %, p = 0,01) moins de stades I (35 % vs 48 %, p = 0,01). Le risque d’avoir un mélanome avec un Breslow ≥ 0,8 mm (OR = 1,75 ; IC95 % [1,19–2,63], p = 0,006), et d’être ulcéré (OR = 1,69 ; IC95 % [1,05–2,80], p = 0,034) était plus élevé en PC vs EPC ; le risque d’être en stade III d’emblée tendait à être plus élevé également (OR = 0,64 ; IC95 % [0,37–1,01], p = 0,06).

Discussion

Notre étude montre que le confinement du printemps 2020 en Île-de-France a eu un impact immédiat de diminution > 15 % de nouveaux diagnostics de mélanomes par rapport à une période équivalente l’année précédente et que cette baisse de fréquentation a eu des conséquences en terme de sévérité sur les mélanomes diagnostiqués les mois suivant cette période. Ainsi, le confinement peut être interprété comme un modèle expérimental démontrant qu’un retard diagnostique de 9 semaines peut entraîner une augmentation de la sévérité des mélanomes incidents, pouvant avoir des conséquences de morbi-mortalité et économiques. Le taux de mélanome in situ stable est en faveur de l’absence d’impact d’un retard modéré de diagnostic de ces mélanomes à croissance lente. Cette étude souligne l’importance des stratégies de dépistage pour les patients à risque, et l’intérêt de nouvelles pratiques comme la télémédecine pour tenter de limiter les délais de consultation de dépistage et de diagnostic.

Impact of prior treatment with immune checkpoint inhibitors on dacarbazine efficacy in metastatic melanoma

BACKGROUND

Despite its low efficacy, chemotherapy with dacarbazine remains an option in metastatic melanoma patients after failure of immune checkpoint inhibitors (ICI) ± targeted therapy. Some observations suggested an increased efficacy of chemotherapy in melanoma or lung cancer patients previously treated with ICI; we aimed to evaluate the efficacy of dacarbazine in a controlled-group study of patients pre-treated or not with ICI.

METHODS

We retrospectively collected data from all consecutive patients treated with dacarbazine for advanced cutaneous melanoma without brain metastasis, in our skin cancer centre between June 2006 and September 2019. The primary endpoint was progression-free survival (PFS); secondary endpoints were overall response rates (ORR), overall survival (OS) and safety of dacarbazine.

RESULTS

Among 72 patients, 17 (23.6%) received dacarbazine after ICI and 55 (76.3%) without prior ICI. Despite less favourable prognostic factors in patients ICI-pre-treated, median PFS was 4.27 months (range 0.89-43.69) in this group versus 2.04 months (range 1.25-39.25) P = 0.03 in non-ICI-pre-treated patients; ORR were 35.3% and 12.7%, respectively. The median OS and the occurrence of adverse events were similar in both groups.

CONCLUSION

Dacarbazine seems to offer a short-lived benefit in patients with progressive advanced disease despite ICI (±targeted therapy), and could be an alternative before considering best supportive care.

Monitoring of plasma concentrations of dabrafenib and trametinib in advanced BRAFV600mut melanoma patients

BACKGROUND

Dabrafenib (D) and trametinib (T) improved survival in patients with BRAFV600^mut melanoma. High plasma concentration of D (PCD) is weakly associated with adverse events (AE). We investigated the relationship between PCD/T and tumour control or AE.

METHODS

We analysed PCD/T in patients treated with D+T for metastatic melanoma. We collected data of tumour response (RECIST 1.1) and AE (CTCAE 4.0) blinded to PCD/T results.

RESULTS

We analysed 71 D and 58T assays from 34 patients. High inter-individual variability of PCD (median: 65.0ng/mL; interquartile range (IQR) [4-945]) and of PCT (median: 8.6ng/mL; IQR [5-39]) was observed. We found a weak relationship between PCD and progression-free survival, taking follow-up time into account (hazard ratio 0.991; 95%CI, 0.981 to 1.000; P=0.06). However, no difference was observed between mean PCD/T of progressing patients (n=21; 125±183ng/mL and 9.3±3.6ng/mL, respectively) and responders (complete, partial or stable response) (n=13; 159±225ng/mL, P=0.58 and 10.6±24.4ng/mL, P=0.29, respectively). No significant relationship was found between PCD/T and most common AEs (fever, lymphopenia, CPK increase, and hepatic cytolysis), body mass index, or age. Mean CPT (n=16) was significantly higher for female subjects (n=18; 11.5±4.8ng/mL) than for male subjects (8.8ng/mL±2.9, P=0.01), but no difference was observed between sex and CPD (P=0.32).

CONCLUSION

Our study showed a weak relationship between PCD and progression-free survival, but no relationship between PCD/T and AE was found. Monitoring PCD and PCT alone is unlikely to be useful in assessing response to treatment.

Which adjuvant treatment for patients with BRAFV600-mutant cutaneous melanoma?

Treatment of patients with melanoma has considerably improved over the past decade and more recently with adjuvant therapies for patients with American Joint Committee on Cancer (AJCC) stage III (loco-regional metastases) or IV (distant metastases) totally resected melanoma, in order to prevent recurrence. In the adjuvant setting, two options are available to patients with BRAF^V600-mutant AJCC stage III totally resected melanoma: anti-PD-1 blockers (nivolumab or pembrolizumab) or BRAF plus MEK inhibitors (dabrafenib plus trametinib). In the absence of comparative studies, it is difficult to determine which of these options is best. Our aim was to review published studies focusing on the management of patients with BRAF^V600-mutant melanoma in the adjuvant setting. We also reviewed the main clinical trials of BRAF plus MEK inhibitors and immunotherapy in advanced (i.e. unresectable metastatic) BRAF-mutant melanoma in an attempt to identify results potentially affecting the management of patients on adjuvants. More adverse events are observed with targeted therapy, but all resolve rapidly upon drug discontinuation, whereas with immune checkpoint blockers some adverse events may persist. New therapeutic strategies are emerging, notably neoadjuvant therapies for stage III patients and adjuvant therapies for stage II patients; the place of the adjuvant strategy amidst all these options will soon be re-evaluated. The choice of adjuvant treatment could influence the choice of subsequent treatments in neo-adjuvant or metastatic settings. This review will lead clinicians to a better understanding of the different adjuvant treatments available for patients with totally resected AJCC stage III and IV BRAF^V600-mutant melanoma before considering subsequent treatment strategies.

A Multicenter Analysis of Immune Checkpoint Inhibitors as Adjuvant Therapy Following Treatment of Isolated Brain Metastasis

BACKGROUND

The objective of this work was to characterize outcomes of patients with isolated brain metastases managed with local therapy followed by immune checkpoint inhibitor (ICI) therapy.

MATERIALS AND METHODS

Patients from four medical centers were included if they presented with isolated brain metastases treated with local therapy and received adjuvant treatment with ICIs.

RESULTS

Eleven patients with median size of largest brain metastasis of 3.9 cm, treated with surgical resection (n = 8) and/or stereotactic radiosurgery (SRS; n = 6), were included. Ipilimumab/nivolumab was the adjuvant ICI used in four patients, of whom one recurred (25%) and none died, compared with three of seven (43%) who recurred and two of seven (29%) who died following adjuvant treatment with ICI monotherapy. All recurrences were intracranial.

CONCLUSION

Patients with isolated brain metastases treated with surgery or SRS appeared to benefit from adjuvant ICI therapy, particularly with combination therapy. Recurrences in this setting appear to largely occur intracranially.

Clinical Pharmacology and Interplay of Immune Checkpoint Agents: A Yin-Yang Balance

T cells have a central role in immune system balance. When activated, they may lead to autoimmune diseases. When too anergic, they contribute to infection spread and cancer proliferation. Immune checkpoint proteins regulate T cell function, including cytotoxic T lymphocyte antigen-4 (CTLA-4) and programmed cell death-1 (PD-1) and its ligand (PD-L1). These nodes of self-tolerance may be exploited pharmacologically to downregulate (CTLA-4 agonists) and activate [CTLA-4 and PD-1/PD-L1 antagonists, also called immune checkpoint inhibitors (ICIs)] the immune system.CTLA-4 agonists are used to treat rheumatologic immune disorders and graft rejection. CTLA-4, PD-1, and PD-L1 antagonists are approved for multiple cancer types and are being investigated for chronic viral infections. Notably, ICIs may be associated with immune-related adverse events (irAEs), which can be highly morbid or fatal. CTLA-4 agonism has been a promising method to reverse such life-threatening irAEs. Herein, we review the clinical pharmacology of these immune checkpoint agents with a focus on their interplay in human diseases.

BET bromodomain inhibitor HMBA synergizes with MEK inhibition in treatment of malignant glioma

(1) Background: BET bromodomain proteins regulate transcription by binding acetylated histones and attracting key factors for, e.g., transcriptional elongation. BET inhibitors have been developed to block pathogenic processes such as cancer and inflammation. Despite having potent biological activities, BET inhibitors have still not made a breakthrough in clinical use for treating cancer. Multiple resistance mechanisms have been proposed but thus far no attempts to block this in glioma has been made. (2) Methods: Here, we have conducted a pharmacological synergy screen in glioma cells to search for possible combination treatments augmenting the apoptotic response to BET inhibitors. We first used HMBA, a compound that was developed as a differentiation therapy four decades ago but more recently was shown to primarily inhibit BET bromodomain proteins. Data was also generated using other BET inhibitors. (3) Results: In the synergy screen, we discovered that several MEK inhibitors can enhance apoptosis in response to HMBA in rat and human glioma cells in vitro as well as in vivo xenografts. The combination is not unique to HMBA but also other BET inhibitors such as JQ1 and I-BET-762 can synergize with MEK inhibitors. (4) Conclusions: Our findings validate a combination therapy previously demonstrated to exhibit anti-cancer activities in multiple other tumour types but which appears to have been lost in translation to the clinic.

Second primary melanoma in advanced melanoma patients treated with anti-PD-1 monoclonal antibodies

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Background: Development of a second primary melanoma (SCPM) has not been reported in melanoma patients treated with anti-PD-1 monoclonal antibodies (mAb), in contrast with those reported in BRAF-inhibitor-treated patients. Our aim was to report arising SCPM in patients with advanced melanoma treated with anti-PD-1 therapy. Methods: Retrospective study, conducted in 2 referral centres, including advanced melanoma patients who developed a SCPM after anti-PD-1 mAb initiation, between September 2010 and May 2019. BRAF or NRAS mutational status was assessed by targeted NGS panels, real-time PCR, and immunohistochemistry. Results: Among a total of 509 patients treated with anti-PD-1 mAb, 4 had a SCPM (incidence: 0.8%; 95%CI: 0.02-1.57%). All patients were treated with nivolumab, in first (N = 3) or second line after progression with BRAF + MEK inhibitors (N = 1). No immune-related adverse event greater than grade 2 according to Common Terminology Criteria for Adverse Events version 5.0. was observed in these 4 cases; a vitiligo-like depigmentation (grade 1) was observed in two patients. The median time from the first nivolumab infusion to the SCPM diagnosis was 17.5 months (range: 5-21). All patients developed the SCPM after achieving a complete response. Nivolumab administration had been discontinued (4 months prior) in one patient. Histology revealed 4 superficial spreading melanomas (SSM): one invasive (without BRAFV600 mutation) and 3 intraepidermal melanomas (2 with a BRAFV600E mutation and one with a NRASQ61H mutation). 3 patients had risk factors for developing multiple melanomas: a dysplastic nevus syndrome, a high number of nevi (≥100 nevi), and a family history of melanoma in first-degree relatives and constitutional heterozygous mutation of exon 2 of the CDKN2A gene. Occurrence of SPCM did not alter advanced melanoma treatment. With a median follow-up of 29 months [range: 18-41] from the first anti-PD-1 mAb infusion, all patients had prolonged CR, and treatment was discontinued in all patients, without relapse after a median 11.5 months [0-18] off therapy. The median duration of nivolumab treatment was 15.5 months [10-24]. Conclusions: Although anti-PD-1 mAb could theoretically decrease the risk of developing another melanoma in metastatic melanoma patients, we found 4 such cases, highlighting the importance of regular clinical screenings for new primary melanoma in patients with metastatic melanoma even when responsive to anti-PD-1 therapy. Immune checkpoint inhibitors do not totally prevent the risk of occurrence a SCPM.

Efficacy of late concurrent hypofractionated radiotherapy in advanced melanoma patients failing anti-PD-1 monotherapy

Advanced melanoma patients who failed anti-PD-1 therapy have limited options. We analyzed a cohort of 133 advanced melanoma patients receiving anti-PD-1 monotherapy in a referral center between April 2015 and December 2017, and included the 26 patients with confirmed progressive (PD) or stable disease who received additional radiotherapy with an unmodified anti-PD-1 mAb regimen. Tumor evaluations were done on radiated and nonradiated (RECIST 1.1) lesions, with abscopal effect defined as a partial (PR) or complete response (CR) outside radiated fields. Primary endpoint was the CR + PR rate in radiated + nonradiated lesions. Secondary endpoints were progression-free survival (PFS), melanoma-specific survival (MSS) and safety. First late radiotherapy, consisting of hypofractionated radiotherapy (3-5 sessions, 20-26 Gy), standard palliative radiotherapy or brain radiosurgery was begun after a median of 6.3 months of anti-PD-1 in 23, 2 and 1 patient(s), respectively. Best response was 8 (31%) CR, 2 (8%) profound PR allowing surgical resection of remaining metastases and 16 (62%) PD. Abscopal effect was seen in 35% of patients. Median PFS and MSS since anti-PD-1 initiation was 15.2 [95% CI: 8.0 not achieved (na)] and 35.3 [95% CI: 18.5 na] months, respectively. PFS curves seemed to achieve a plateau. We discontinued anti-PD-1 therapy in 9/10 of patients with no residual evaluable disease and observed one relapse after a median of 10 months off anti-PD1-therapy. No unusual adverse event was recorded. Limitations of the study include its retrospective nature and limited size. Hypofractionated radiotherapy may enhance anti-PD1 monotherapy efficacy in patients who previously failed anti-PD-1 therapy. Controlled studies are needed.

Correction: A patient-derived xenograft pre-clinical trial reveals treatment responses and a resistance mechanism to karonudib in metastatic melanoma

On Pubmed, the name of co-author Roger Olofsson Bagge appeared incorrectly as "Bagge RO" instead of "Olofsson Bagge, Roger". This has been corrected in the PDF and HTML versions.

Safety and Efficacy of Immune Checkpoint Inhibitors in Patients With Cancer and Preexisting Autoimmune Disease: A Nationwide, Multicenter Cohort Study

OBJECTIVE

Immune checkpoint inhibitors (ICIs) for cancer therapy frequently induce immune-related adverse effects (IRAEs). Therefore, most patients with preexisting autoimmune diseases have been excluded from clinical trials of ICIs. This study was undertaken to evaluate the safety and efficacy of ICIs in patients with preexisting autoimmune disease and cancer.

METHODS

A retrospective cohort study was conducted from January 2017 to January 2018 via 3 French national networks of experts in oncology and autoimmunity. Adults with preexisting autoimmune disease who were receiving ICIs were assessed for the occurrence of flare of preexisting autoimmune disease, other IRAEs, and cancer response.

RESULTS

The study included 112 patients who were followed up for a median of 8 months. The most frequent preexisting autoimmune diseases were psoriasis (n = 31), rheumatoid arthritis (n = 20), and inflammatory bowel disease (n = 14). Twenty-four patients (22%) were receiving immunosuppressive therapy at ICI initiation. Autoimmune disease flare and/or other IRAE(s) occurred in 79 patients (71%), including flare of preexisting autoimmune disease in 53 patients (47%) and/or other IRAE(s) in 47 patients (42%), with a need for immunosuppressive therapy in 48 patients (43%) and permanent discontinuation of ICI in 24 patients (21%). The median progression-free survival was shorter in patients receiving immunosuppressive therapy at ICI initiation (3.8 months versus 12 months; P = 0.006), confirmed by multivariable analysis. The median progression-free survival was shorter in patients who experienced a flare of preexisting autoimmune disease or other IRAE, with a trend toward better survival in the subgroup without immunosuppressant use or ICI discontinuation.

CONCLUSION

Our findings indicate that flares or IRAEs occur frequently but are mostly manageable without ICI discontinuation in patients with a preexisting autoimmune disease. Immunosuppressive therapy at baseline is associated with poorer outcomes.

Efficacy of hypofractionated radiotherapy (Rx) in melanoma patients who failed anti-PD-1 monotherapy: Assessing the abscopal effect

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Background: Radiotherapy (Rx) and anti-PD-1 mAb are potentially synergistic. No study has tested this combination only in pts who failed on anti-PD-1 mAb, which allows to assess the abscopal effect. We evaluated this combination in a cohort of advanced melanoma pts after failure of anti-PD-1 monotherapy. Methods: Analysis of a prospective database in a referral center searching for advanced melanoma pts with confirmed (2 CT-scans) progressive (PD) or stable (SD) disease on anti-PD-1 monotherapy, who later received concurrent Rx without modification of anti-PD-1 mAb regimen. Radiologists performed independent tumor evaluations (RECIST 1.1) every 3 m, both on radiated and non-radiated lesions, with abscopal effect defined as a partial (PR) or complete (CR) response outside radiated fields. Results: 26 pts (21 achieving PD, 5 SD, 10 pt ≥3 involved organs), mean age 70 Y, were included. Anti-PD-1 mAb was first line in 50% of pts. Rx, consisting of hypofractionnated Rx (3-5 sessions, 26 Gy), standard palliative Rx, or gamma-knife in respectively 23, 2, and 1 pts, was begun on a single site in 73% of pts or on 2 sites after a median of 5 m after beginning anti-PD-1 mAb. Median follow-up after onset of anti-PD-1 mAb was 17 (7-35) m, with 65% of pts alive at last follow-up. Best response was 7 CR (27%, including CR in 4 pts with prior PD) 1 PR, 3 SD (12%), 15 PD (58%). Abscopal effect was seen in 10 pts (38%). No correlation between the occurrence of CR and BRAF/NRAS mutation status, number of metastatic sites, presence or absence of brain metastases, and LDH level was seen. Anti-PD-1 mAb could be discontinued in 6 pts with CR, without relapse to date. No unusual adverse event was recorded. Conclusions: In pts who have previously failed on anti-PD-1 mAb, obtaining with concurrent Rx and without modifying anti-PD-1 mAb, CR or PR in 30% of pts, median OS not achieved, and abscopal effect in > 1/3 of pts is probably not due only to late efficacy of anti-PD-1 mAb but suggests a synergy with RT. Release after radiation of tumor neoantigens may stimulate immune response. Hypo-fractionated radiotherapy may enhance anti-PD1 monotherapy efficacy in melanoma pts who failed on anti-PD-1 mAb. Controlled studies are needed.

Plasma concentrations of dabrafenib and trametinib (PCD/T) monitoring in advanced BRAFV600mut melanoma patients

9541

Background: Dabrafenib (D) and trametinib (T) are highly ative in BRAFV600mut melanoma pts. One previous study suggested high PCD to be associated with adverse effects (AE) but not with tumor response. We investigated the relationship between PCD/T and tumor control or AE. Methods: PCD/T were evaluated with high-performance liquid chromatography/mass spectrometry in D+T-treated metastatic melanoma patients. We analyzed results at steady state (≥2 d for D, 24 d for T after introduction or dose modification) and far from peak concentrations (8 to 14.5 h for D and 20-28 h for T). We collected data of tumor assessments (RECIST 1.1) prospectively stored in our database and AE (CTCAE 4.0) blinded to PCD/T results. Each AE was associated with the closest sample harvested to the beginning of AE, or in the absence of AE with the highest PCD/T level for each patient. Results: We analyzed 75 D and 58 T assays from 36 pts (19M/17F), treated with D+T for metastatic melanoma (Stage IV: N = 35), mostly in first line (69.4%). Initial D dose was 300 mg/d and 2 mg/d for T, reduced in 10 patients (27.7%) for AE: to 30% of D (N = 8) and 25% of T (N = 8). High interindividual variability of PCD (range: 4-945ng/mL, median 70.0) and of PCT (5-25ng/mL, median 8.6) was observed. No differences between mean PCD/T at the time of evaluations showing progressive disease (PD) compared to those without PD pts (146.6±111.6 and 9.3±2.1) and pts with complete (N = 11), partial (N = 1) or stable response (N = 1) (160.6±127.9, P = 0.81 and 10.6ng/mL±2.6, P = 0.29) were observed. No significant relationship was shown between PCD/T and body mass index (r = 0.22 and -0.31), age (p = 0.19 and 0.26), or between PCD/T and D (p = 0.11) or T (p = 0.17) doses, neither between elevated mean PCD/T and any most common AE. Conclusions: This study shows a high interindividual variability but failed to show a relationship between PCD or T and tumor response nor AE. One limit is we did not explore PC of D active metabolites (hydroxy-and desmethylD). It has been shown that there is an auto-induction of D; T inhibits P-gp, a D substrate, suggesting synergistic pharmacological interactions. Thus, D pharmacokinetic seems to be too complex to be easily monitored.

A patient-derived xenograft pre-clinical trial reveals treatment responses and a resistance mechanism to karonudib in metastatic melanoma

Karonudib (TH1579) is a novel compound that exerts anti-tumor activities and has recently entered phase I clinical testing. The aim of this study was to conduct a pre-clinical trial in patient-derived xenografts to identify the possible biomarkers of response or resistance that could guide inclusion of patients suffering from metastatic melanoma in phase II clinical trials. Patient-derived xenografts from 31 melanoma patients with metastatic disease were treated with karonudib or a vehicle for 18 days. Treatment responses were followed by measuring tumor sizes, and the models were categorized in the response groups. Tumors were harvested and processed for RNA sequencing and protein analysis. To investigate the effect of karonudib on T-cell-mediated anti-tumor activities, tumor-infiltrating T cells were injected in mice carrying autologous tumors and the mice treated with karonudib. We show that karonudib has heterogeneous anti-tumor effect on metastatic melanoma. Thus, based on the treatment responses, we could divide the 31 patient-derived xenografts in three treatment groups: progression group (32%), suppression group (42%), and regression group (26%). Furthermore, we show that karonudib has anti-tumor effect, irrespective of major melanoma driver mutations. Also, we identify high expression of ABCB1, which codes for p-gp pumps as a resistance biomarker. Finally, we show that karonudib treatment does not hamper T-cell-mediated anti-tumor responses. These findings can be used to guide future use of karonudib in clinical use with a potential approach as precision medicine.

Efficacy of combined hypo-fractionated radiotherapy and anti-PD-1 monotherapy in difficult-to-treat advanced melanoma patients

Information on the role of radiotherapy in anti-PD-1 monoclonal antibody-treated melanoma patients is limited. We report on a prospective cohort of advanced melanoma patients treated simultaneously with radiotherapy and anti-PD-1 therapy between 01/01/15 and 30/06/16. Tumor evaluations (RECIST 1.1) were performed every 3 months on radiated and non-radiated lesions. Twenty-five advanced melanoma patients (64% AJCC stage IV M1c, 64% on second-line treatment or more, 60% with elevated LDH serum levels) were included. Radiotherapy was performed early (median: 24 days) after the first anti-PD-1 dose in 15 patients with rapidly progressing symptomatic lesion(s) or later (median: 5.4 months) in 10 patients with progressive disease (PD) despite PD-1 blockade. Radiotherapy was limited to one organ in 24 patients and consisted mainly of hypo-fractioned radiotherapy (median dose 26 Gy in 3–5 fractions, 17 patients) or brain radiosurgery (5 patients). Median follow-up after first anti-PD-1 dose was 16.9 m (range 2.7-27.4), with 44% of patients alive at last follow-up. For radiated lesions, rates of complete (CR), partial (PR) responses, stable disease (SD) or PD were 24%, 12%, 24%, and 32%, respectively. For non-radiated lesions, rates of CR, PR, SD, and PD were 20%, 19%, 12%, and 40%, respectively. Responses achieved after radiotherapy for radiated and non-radiated areas were correlated (Pearson correlation r: 0.89, P<0.0001) suggesting an abscopal effect. Five patients with CR remained disease-free after discontinuation of anti-PD-1 for a median of 9.5 months. No unusual adverse event was recorded. Hypo-fractionated radiotherapy may enhance efficacy of anti-PD1 therapy in difficult-to-treat patients. Controlled studies are needed.

Variation of mutant allele frequency in NRAS Q61 mutated melanomas

BACKGROUND

Somatic mutations of BRAF or NRAS activating the MAP kinase cell signaling pathway are present in 70% of cutaneous melanomas. The mutant allele frequency of BRAF V600E (M%BRAF) was recently shown to be highly heterogeneous in melanomas. The present study focuses on the NRAS Q61 mutant allele frequency (M%NRAS).

METHODS

Retrospective quantitative analyze of 104 NRAS mutated melanomas was performed using pyrosequencing. Mechanisms of M%NRAS imbalance were studied by fluorescence in situ hybridization (FISH) and microsatellite analysis.

RESULTS

M%NRAS was increased in 27.9% of cases. FISH revealed that chromosome 1 instability was the predominant mechanism of M%NRAS increase, with chromosome 1 polysomy observed in 28.6% of cases and intra-tumor cellular heterogeneity with copy number variations of chromosome 1/NRAS in 23.8%. Acquired copy-neutral loss of heterozygosity (LOH) was less frequent (19%). However, most samples with high M%NRAS had only one copy of NRAS locus surrounding regions suggesting a WT allele loss. Clinical characteristics and survival of patients with either <60% or ≥60% of M%NRAS were not different.

CONCLUSION

As recently shown for M%BRAF, M%NRAS is highly heterogeneous. The clinical impacts of high M%NRAS should be investigated in a larger series of patients.

Increase in NRAS mutant allele percentage during metastatic melanoma progression

One-fifth of cutaneous melanomas have dominant gain-of-function mutations of the NRAS oncogene. We report the first two cases of increasing NRAS mutant allele frequency in melanoma metastases and show that the chromosomal mechanism of this homozygosity is an increased polysomy of chromosome 1. We observed an increase in NRAS mutant allele percentage (NRAS-MA%) in the metastatic melanoma progression from 2 patients with melanomas harbouring a NRAS mutation (p.Q61K in case 1 and p.Q61R in case 2). In case 1, we observed a NRAS-MA% increase from 18% within the first metastatic node to 81%, 92% and 85% respectively in the three subsequent metastases: lymph node, brain and subcutaneous metastases biopsied 1, 6 and 17 months, respectively, after the initial lymph node biopsy. In case 2, we observed an increase in NRAS-MA% from 40% within the primary melanoma to 63% within the metastatic lymph node. FISH analysis showed the same results in both cases: a frequent polysomy of chromosome 1 in metastasis samples with NRAS mutant allele percentage >60%, while most cells were disomic in the samples with well-balanced heterozygous mutations. The percentage of NRAS mutant allele may increase during metastatic progression and may be associated with chromosomal instability. Further studies are needed to evaluate the prognostic impact of the NRAS homozygous status and/or polyploidy in metastatic cutaneous melanomas.

Prognostic Value of 25-hydroxyvitamin D3 Levels at Diagnosis and During Follow-up in Melanoma Patients

BACKGROUND

A low 25-hydroxyvitamin D3 (25(OH)D3) serum concentration at melanoma diagnosis might be associated with worse survival. We prospectively studied the prognostic value of 25(OH)D3 at diagnosis and during follow-up.

METHODS

MelanCohort is a cohort of invasive melanoma patients. Serum 25(OH)D3 was measured by mass spectrometry and standardized on month of blood drawn, age, sex, and body mass index (BMI). Role of 25(OH)D3 levels and risk of relapse was analyzed in a Cox proportional hazards model adjusting for age, sex, BMI, and American Joint Committee on Cancer (AJCC) stage. All statistical tests were two-sided.

RESULTS

One thousand one hundred seventy-one patients were included. 25(OH)D3 levels at diagnosis (median = 49.0 nmol/L) were inversely correlated with prognostic factors such as AJCC stage (P < .001 Kruskal-Wallis), Breslow's thickness (P < .001 Spearman correlation), and ulceration (P < .001 Kruskal-Wallis), but not with risk of relapse. Changes in 25(OH)D3 levels during follow-up were associated with worse prognosis: With a third quartile Q3 of average change per year (-0.30 to 4.60 nmol/L/Y) used as reference, hazard ratios for the first, second, and fourth quarters were 1.94 (95% confidence interval [CI] = 1.36 to 2.76), 1.23 (95% CI = 0.85 to 1.78), and 1.61 (95% CI = 1.14 to 2.28), respectively. In sensitivity analyses, no changes were observed either by AJCC stage, number of 25(OH)D3 measures performed, or by 25(OH)D3 level at baseline. No evidence of reverse causation was identified. Analyses performed on overall survival yielded similar results.

CONCLUSIONS

We show that 25(OH)D3 variation during follow-up is an independent melanoma prognostic marker, but not its level at diagnosis. Previously reported associations between low 25(OH)D3 level at diagnosis and poor prognosis seem to be due to insufficient adjustment for prognostic factors.

Variations of BRAF mutant allele percentage in melanomas

Background

BRAF mutations are present in 40 % of human skin melanomas. Mutated tumors with an increased percentage of BRAF mutant alleles (BRAF-M%) may have a better response to RAF/MEK inhibitors. We evaluated the BRAF-M% in melanomas, and the genetic causes of its variation.

Methods

BRAF-M% was quantified by pyrosequencing, real-time PCR (rtPCR) and/or picoliter-droplet PCR (dPCR). BRAF mutant expression was detected by immunohistochemistry. Chromosomal alterations were analyzed with fluorescence in situ hybridization (FISH), and single nucleotide polymorphism (SNP) arrays.

Results

BRAF-M% quantification obtained with pyrosequencing was highly correlated (R = 0.94) with rtPCR, and with dPCR. BRAF-M% quantified from DNA and RNA were also highly correlated (R = 0.98). Among 368 samples with >80 % tumor cells, 38.6 % had a BRAF^V600E mutation. Only 66.2 % cases were heterozygous (BRAF-M% 30 to 60 %). Increased BRAF-M% (>60 %) was observed in 19 % of cases. FISH showed a polysomy of chromosome 7 in 13.6 %, 35.3 % and 54.5 % of BRAF wild-type, heterozygous and non-heterozygous BRAF-mutated samples, respectively (P < 0.005). Amplification (5.6 %) and loss (3.2 %) of BRAF locus were rare. By contrast, chromosome 7 was disomic in 27/27 BRAF-mutated nevi.

Conclusions

BRAF-M% is heterogeneous and frequently increased in BRAF-mutant melanomas. Aneuploidy of chromosome 7 is more frequent in BRAF mutant melanomas, specifically in those with high BRAF-M%.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-015-1515-3) contains supplementary material, which is available to authorized users.

Immunohistochemistry as a potential tool for routine detection of the NRAS Q61R mutation in patients with metastatic melanoma

BACKGROUND

It can be useful to assess the NRAS mutation status in patients with metastatic melanoma because NRAS-activating mutations confer resistance to RAF inhibitors, and NRAS-mutated patients appear to be sensitive to mitogen-activated protein kinase (MEK) inhibitors.

OBJECTIVE

We aimed to assess the diagnostic accuracy of an immunohistochemistry (IHC) approach using a novel anti-NRAS (Q61R) monoclonal antibody on formalin-fixed paraffin-embedded tissue samples from patients with metastatic melanoma.

METHODS

We conducted a retrospective multicenter cohort study on 170 patients with metastatic melanoma. The automated IHC assay was performed using the SP174 clone, and compared with results of the molecular testing.

RESULTS

Evaluation of a test cohort with knowledge of the mutation status established a specific IHC pattern for the mutation. In the independent blinded analysis of the remaining cases, the anti-NRAS (Q61R) antibody accurately identified all NRAS Q61R-mutated tumors, and demonstrated 100% sensitivity and specificity.

LIMITATIONS

Limitations include retrospective design and lack of multicenter interobserver reproducibility.

CONCLUSION

The NRAS (Q61R) IHC assay is reliable and specific for the evaluation of the Q61R mutation status in metastatic melanoma and may be an alternative to molecular biology in evaluation of metastatic melanoma in routine practice.

Plasma vemurafenib concentrations in advanced BRAFV600mut melanoma patients: impact on tumour response and tolerance

BACKGROUND

Vemurafenib improves survival in advanced BRAFV600(mut) melanoma patients, but tolerance is often poor and resistance frequently occurs, without predictive factor. Our aim was to investigate for the first time a relationship between plasma vemurafenib concentration (PVC) and efficacy or tolerance.

METHODS

Plasma samples from unresectable metastatic BRAFV600(mut) melanoma patients treated with vemurafenib monotherapy were prospectively collected at each tumour response evaluation (RECIST 1.1) or when adverse event occurred (CTCAE 4.0). PVC was measured with liquid chromatography-tandem mass spectrometry. Herein, we report on PVC at steady state (≥14 days after vemurafenib introduction or dose modification). Samples collected after first melanoma progression were excluded from the response analysis. All samples were analysed in the tolerance analysis. We kept the closest collected sample from the onset of each adverse effect or the one with the highest PVC in the absence of this adverse effect. Comparisons of means (Student's t-tests and Wilcoxon rank sum tests) and of frequencies (χ(2) tests) were carried out. A logistic regression analysis identified predictors of progression.

RESULTS

We included 105 plasma samples in 23 patients (10M/13F). Initial vemurafenib dose was 960 mg b.i.d., reduced by 25% (8 patients) or 50% (2 patients) for intolerance in 10 patients (44%). PVC displayed high inter-individual variability (13.0-109.8 µg/ml, median 54.0). Mean PVC was lower at time of first progression (38.8 ± 19.7 µg/ml) than mean PVC found when tumour was stable or in partial or complete response (56.4 ± 21.0 µg/ml, P = 0.013, 21 patients). Logistic regression revealed that having a low PVC (P = 0.01) or brain metastasis (P = 0.01) were both significantly and independently associated with tumour progression. High PVC was not statistically significantly associated with the occurrence of adverse effects.

CONCLUSION

PVC at steady state is highly variable and low PVC was associated with tumour progression, suggesting a new path to melanoma resistance to vemurafenib.

Inhibition of CD39 enzymatic function at the surface of tumor cells alleviates their immunosuppressive activity

The ectonucleotidases CD39 and CD73 hydrolyze extracellular adenosine triphosphate (ATP) and adenosine diphosphate (ADP) to generate adenosine, which binds to adenosine receptors and inhibits T-cell and natural killer (NK)-cell responses, thereby suppressing the immune system. The generation of adenosine via the CD39/CD73 pathway is recognized as a major mechanism of regulatory T cell (Treg) immunosuppressive function. The number of CD39⁺ Tregs is increased in some human cancers, and the importance of CD39⁺ Tregs in promoting tumor growth and metastasis has been demonstrated using several in vivo models. Here, we addressed whether CD39 is expressed by tumor cells and whether CD39⁺ tumor cells mediate immunosuppression via the adenosine pathway. Immunohistochemical staining of normal and tumor tissues revealed that CD39 expression is significantly higher in several types of human cancer than in normal tissues. In cancer specimens, CD39 is expressed by infiltrating lymphocytes, the tumor stroma, and tumor cells. Furthermore, the expression of CD39 at the cell surface of tumor cells was directly demonstrated via flow cytometry of human cancer cell lines. CD39 in cancer cells displays ATPase activity and, together with CD73, generates adenosine. CD39⁺CD73⁺ cancer cells inhibited the proliferation of CD4 and CD8 T cells and the generation of cytotoxic effector CD8 T cells (CTL) in a CD39- and adenosine-dependent manner. Treatment with a CD39 inhibitor or blocking antibody alleviated the tumor-induced inhibition of CD4 and CD8 T-cell proliferation and increased CTL- and NK cell-mediated cytotoxicity. In conclusion, interfering with the CD39-adenosine pathway may represent a novel immunotherapeutic strategy for inhibiting tumor cell-mediated immunosuppression.

A LC/MS/MS micro-method for human plasma quantification of vemurafenib. Application to treated melanoma patients

As previously shown for imatinib, therapeutic drug monitoring (TDM) of vemurafenib should be important to measure efficacy of the treatment in melanoma patient. A micro-method based on liquid chromatography coupled to triple quadrupole spectrometry detection using only 10μL of plasma was validated. A simple protein precipitation with water/acetonitrile was used after addition of vemurafenib-(13)C6 as internal standard. The ion transitions used to monitor analytes were m/z 490.2→m/z 255.2 and m/z 383.3 for vemurafenib and m/z 496.2→m/z 261.2 and m/z 389.3 for vemurafenib-(13)C6. Calibration curves were linear in the 0.1-100μg/mL range, the limits of detection and quantification being 0.01μg/mL and 0.1μg/mL, respectively. The intra- and inter-assay precisions evaluated at 0.1, 0.3, 15, 45 and 80μg/mL were lower than 13.3% and the accuracies were in the 93.7-105.8 range. No matrix effect was observed. At steady state, the results of TDM of vemurafenib in 26 patients treated by 960mg twice daily (n=60 samples), 13 patients with 740mg twice daily (n=13) and one with 1200mg twice daily (n=3) showed a great variability of the pharmacokinetics of this compound.