Clinical observation of panniculitis in two patients with BRAF-mutated metastatic melanoma treated with a combination of a BRAF inhibitor and a MEK inhibitor

Background

Treatment with selective BRAF or MEK inhibitors is frequently associated with cutaneous toxicities, including squamous cell carcinoma (SCC), papillomas and rash. These cutaneous adverse effects are typically observed at a lower incidence during combined BRAF and MEK inhibitor therapy.

Patients and Methods

Two male patients with stage IV metastatic BRAF-mutated melanoma were treated with a combination of a selective BRAF inhibitor and a selective MEK inhibitor (dabrafenib and trametinib, or encorafenib (LGX818) and binimetinib (MEK162)) within two different clinical trials. Ten and 150 days after treatment start respectively, the patients developed painful nodules on the legs. In addition, one patient developed symmetrical articulation pain and intermittent fever episodes.

Results

Based on the clinical and histological presentation, erythema nodosum-like panniculitis was diagnosed in both cases. No other aetiology could be found. After receiving topical or oral steroid treatment and anti-inflammatory analgesics, the painful nodular lesions disappeared several weeks later. In one case, a rebound of the painful nodules was observed when the combination treatment (dabrafenib and trametinib) was resumed after a 1-week unscheduled treatment interruption.

Conclusions

Panniculitis has previously been described in association with BRAF inhibitor treatment, but not MEK inhibitor treatment. Combination treatment is usually associated with a lower incidence of cutaneous adverse events (AEs), as compared to monotherapy. Panniculitis was observed in two patients during combined BRAF and MEK inhibitor treatment. These cases illustrate the need for further research in a larger patient population to identify a possible link between combined BRAF and MEK inhibitor treatment and the incidence of panniculitis.

     

Phase 1/2 study assessing the safety and efficacy of dabrafenib and trametinib combination therapy in Japanese patients with BRAF V600 mutation‐positive advanced cutaneous melanoma

The combination of dabrafenib and trametinib demonstrated encouraging antitumor activity and tolerability, at initial analysis, in Japanese patients with BRAF V600 mutant advanced melanoma warranting further investigation. This study evaluated the safety and tolerability, pharmacokinetics (PK) and preliminary efficacy of dabrafenib 150 mg b.i.d. plus trametinib 2 mg q.d. in Japanese patients with BRAF V600E/K mutant solid tumors (phase 1) and melanoma (phase 2). Phase 1 was primarily intended to assess safety and tolerability as assessed by adverse events (AE), and the primary end‐point in phase 2 was to assess confirmed overall response rate (ORR). The secondary end‐points in phase 1 included PK, confirmed/unconfirmed ORR and duration of response (DOR). The secondary end‐points in phase 2 were PK, unconfirmed ORR, DOR, safety and tolerability. A total of 12 cutaneous melanoma patients were enrolled in the study (six in phase 1 and six in phase 2) and received the combination therapy of dabrafenib and trametinib. Common AE (≥50.0%) included pyrexia (75%), increased aspartate aminotransferase (67%), peripheral edema (50%) and nasopharyngitis (50%). The investigator‐assessed ORR was reported in five patients (83%) in phase 1 and was also reported in five patients (83%; 95% confidence interval, 35.9–99.6; P < 0.0001) in phase 2. Plasma concentrations of both dabrafenib and trametinib seemed to a reach steady state by week 3. Overall, efficacy and PK properties for the dabrafenib plus trametinib combination in Japanese patients were comparable with those seen in global studies.     

Real-world efficacy and safety data for dabrafenib and trametinib combination therapy in Japanese patients with BRAF V600 mutation-positive advanced melanoma

We conducted a retrospective investigation of the efficacy and safety of dabrafenib and trametinib combination therapy in Japanese patients with BRAF V600 mutation-positive advanced melanoma in real-world clinical practise. The study analyzed 50 patients who received dabrafenib and trametinib combination therapy for BRAF V600 mutation-positive advanced melanoma in our hospital (26 men and 24 women, aged 21–86 years, inclusive; median age, 53 years). The response rate was 72.3%, with complete response (CR) achieved in eight cases (17.0%), partial response in 26 (55.3%), stable disease in nine (19.1%) and progressive disease in four (8.5%). Median progression-free survival (PFS) was 12 months, and median overall survival (OS) was 23 months. Disease progression occurred in 29 of the 50 patients during the study period, and 25 patients died. Baseline lactate dehydrogenase and the number of organs with metastasis were important predictive factors for PFS and OS, and CR to combination therapy was a predictive factor for long-term remission. Adverse events occurred in 88% of cases; 16% were grade 3 or worse. The adverse events observed in 50% of more of patients were rash (56%) and pyrexia (52%). The efficacy of dabrafenib and trametinib combination therapy in Japanese patients was similar to that reported in global studies, and the same adverse events were generally reported; however, rash tended to occur more frequently in the patients in our study.     

Frequent brain metastases during treatment with BRAF/MEK inhibitors: A retrospective single institutional study

Recent clinical trials revealed that both immune checkpoint inhibitors (ICI) and BRAF/MEK inhibitors significantly prolonged survival in melanoma patients when used for both advanced stage disease and postoperative adjuvant therapy. Although BRAF/MEK inhibitors are associated with a higher objective response rate than ICI, most patients relapse during treatment. However, progression patterns during treatment with BRAF/MEK inhibitors have not been extensively investigated. Here, we retrospectively collected the data of melanoma patients initially treated with BRAF/MEK inhibitors or anti-programmed death 1 (PD-1) antibody monotherapy at the University of Tsukuba Hospital and compared their results. The χ²-test revealed that frequency of brain metastasis (BM) development was significantly higher in cases treated with BRAF/MEK inhibitors compared with those with anti-PD-1 antibody monotherapy. In addition, BM-free survival in cases treated with BRAF/MEK inhibitors was significantly shorter than those treated with anti-PD-1 antibody monotherapy. Our results indicate that BM development during treatment with BRAF/MEK inhibitors may be more frequent than anti-PD-1 antibody monotherapy, even though the extracranial metastases are well controlled. Therefore, we recommend frequent brain examinations during treatment with BRAF/MEK inhibitors to detect BM at an early stage and to promptly administrate ICI with local radiation therapy.     

Treatment of cutaneous T-cell lymphoma with extracorporeal photopheresis monotherapy and in combination with recombinant interferon alfa: A 10-year experience at a single institution

Background: Extracorporeal photopheresis is a pheresis-based therapy that permits the direct targeting of psoralen-mediated photochemotherapy to circulating pathogenic T cells. Although photopheresis is currently used to treat cutaneous T-cell lymphoma (CTCL), limited data are available regarding overall response rates and durability of responses among patients with advanced disease. Furthermore, little is known about the effectiveness and tolerability of combined regimens employing other biologic response modifiers including interferon alfa.Objective: Our purpose was to determine the efficacy of photopheresis among 41 patients with the clinical and laboratory diagnosis of CTCL; the majority of patients had stage III or IV disease with the presence of circulating malignant T cells.Methods: A retrospective chart review during a 10-year period at a single university hospital was performed for all patients receiving either photopheresis monotherapy on two consecutive days every 4 weeks (one cycle) and for an additional 12 patients who also received interferon alfa 1.5 to 5 million U subcutaneously three to five times weekly.Results: Thirty-one of 41 patients (76%) were treated for six or more cycles. The remaining 10 were treated with less than six cycles because of rapidly progressing disease (n = 6), death unrelated to CTCL (n = 2), or withdrawal from treatment (n = 1); one of the 10 patients had only received five cycles of treatment but is still receiving therapy. Twenty-eight of the 31 patients treated for six or more cycles received photopheresis alone. Among the 28, seven patients (25%) had a complete remission, 13 (46%) had a partial remission defined as more than 50% clearing of skin disease, and eight (29%) did not respond to treatment. The presence of Sézary cells in the peripheral blood was associated with a favorable response. Median time to treatment failure was 18 months, whereas median survival from initiation of therapy was 77 months and from the time of diagnosis exceeded 100 months. Nine of these 28 patients went on to receive combination therapy with interferon alfa and, in some cases, other agents. Among these nine patients, five had an enhanced clinical response to the combination therapy compared with treatment with photopheresis monotherapy. The combined regimen was well tolerated.Conclusion: These results indicate that patients with advanced CTCL can achieve a high response rate for an extended period with photopheresis and that interferon alfa combined with photopheresis is a well-tolerated regimen that appears to produce higher response rates than photopheresis alone.     

Real-world efficacy and safety data of nivolumab and ipilimumab combination therapy in Japanese patients with advanced melanoma

The efficacy and safety of nivolumab + ipilimumab combination therapy were retrospectively examined in Japanese patients with unresectable advanced melanoma in clinical practice. Fifty-seven patients with advanced melanoma received the nivolumab + ipilimumab combination therapy. The primary site was cutaneous, mucosal, uveal and unknown in 35, 16, two and four patients, respectively. The overall response rate was 26.3%, with complete response observed in two (3.5%) patients, partial response in 13 (22.8%), stable disease in 12 (21.1%) and progressive disease in 30 (52.6%). The response rate in the treatment-naive and prior systemic therapy group was 40.7% and 13.3%, respectively. For those treated with a single immune checkpoint inhibitor followed by the nivolumab + ipilimumab combination therapy as second-line therapy after disease progression, the response rate was 18.8%. Median progression-free survival (PFS) and overall survival (OS) in all patients was 3.3 and 14 months, respectively. Median PFS in the treatment-naive and prior systemic therapy groups was 13 and 2 months, respectively. Median OS was unreached in the treatment-naive group and was 6.3 months in prior systemic therapy groups. There was no significant difference in PFS and OS for non-acral, acral and mucosal melanoma. Adverse events occurred in 86% of patients; 56.1% were grade 3 or worse. The response rate in an actual clinical setting, including the prior systemic therapy group, was lower than that in the global study and the Japanese phase II study. However, in the treatment-naive group, the rate was equivalent to that in the Japanese phase II study. PFS and OS in the treatment-naive group were comparable with those in the global study and Japanese phase II study, suggesting that the treatment was effective. The proportion of grade 3 and 4 immune-related adverse events was as high as that in the global study and Japanese phase II study.     

Correlation between cutaneous adverse events and prognosis in patients with melanoma treated with nivolumab: A single institutional retrospective study

Treatment for patients with unresectable melanoma has been dramatically changed by the use of immunocheckpoint inhibitors (ICI). In this study, we reviewed patients with unresectable stage III/IV melanoma, who were treated with nivolumab between July 2014 and March 2017 at the Department of Dermatologic Oncology, National Cancer Center Hospital, Tokyo, and retrospectively recorded cutaneous adverse events (cAE), development of vitiligo, clinical characteristics and clinical responses. We identified 128 patients, 61 (47.7%) of whom showed cAE, including 30 (23.4%) with development or exacerbation of vitiligo. The prognosis of patients with melanoma treated with ICI correlated with cAE, including development of vitiligo. Patients with cAE showed better objective responses (41.0% vs 6.0%, P < 0.001), progression-free survival (PFS) (377 vs 61 days, P < 0.001) and overall survival (OS) (763 vs 209 days, P < 0.001) than did patients without cAE. Patients who developed vitiligo showed better objective responses (53.3% vs 29.0% vs 6.0%, P < 0.001), PFS (median, not reached vs 317 vs 65 days, P < 0.001) and OS (not reached vs 689 vs 209 days, P < 0.001) than did patients with other cAE and patients without cAE. Landmark analysis showed development of vitiligo starting 20 weeks after starting nivolumab correlated with better OS. In multivariate analysis, OS correlated with performance status, number of metastasized organs, cAE other than vitiligo and development of vitiligo. Despite the fact that the correlation between other cAE and OS was less than that of vitiligo, cAE may be a simple marker of favorable prognosis.     

Cutaneous manifestations of dabrafenib (GSK2118436): a selective inhibitor of mutant BRAF in patients with metastatic melanoma

Background Inhibitors of mutant BRAF are emerging as standard of care in patients with metastatic melanoma carrying relevant oncogenic mutations. Cutaneous reactions are frequent and significant. We conducted a systematic prospective dermatological review of all patients enrolled at a single institution in the phase I/II clinical trial of the mutant BRAF inhibitor dabrafenib (GSK2118436). Objectives To identify the cutaneous manifestations of the BRAF inhibitor dabrafenib; to form diagnostic criteria to standardize the diagnosis of verrucal keratotic squamoproliferative lesions; and to bring awareness to the medical community of the importance of dermatological assessment of patients taking dabrafenib. Methods Patients enrolled in the phase I/II trial (n = 43) were monitored for the development of new skin lesions. Each new lesion was photographed, a clinical diagnosis recorded and, where appropriate, a biopsy taken. Human papillomavirus (HPV) and p16 immunohistochemistry analyses were performed. Results The most frequently observed lesions were verrucal keratotic squamoproliferative lesions (49%), Grover’s disease (27%) and reactive hyperkeratotic lesions on the soles, at points of friction (22%). Eighteen squamous cell carcinomas (SCCs) occurred in 20% of patients. Most SCCs appeared between weeks 6 and 24 following commencement of therapy on both sun‐damaged and nonsun‐damaged skin. All SCCs were well differentiated, five were of the keratoacanthoma type, and two were SCC in situ. Other lesions observed included seborrhoeic keratoses, epidermal cysts, acneiform eruptions, hair loss and changes in hair structure. HPV was negative in 15 of the 16 tissues studied and p16 expression was higher in SCCs compared with verrucal keratoses. Conclusions Administration of the mutant BRAF inhibitor dabrafenib is associated with induction of keratinocytic proliferation, which in some cases develops features of low‐grade malignancy. Highly oncogenic HPV infection is unlikely to be a contributor to the formation of SCCs or verrucal keratoses.     

Sentinel lymph node biopsy in patients with thick (= 4 mm) melanoma: a single-centre experience

Background and objective Lymphatic mapping/sentinel lymph node biopsy (LM/SLNB) have become routine techniques for staging the regional lymph nodes in early stage melanoma, yet their role in the management of thick (= 4 mm) melanoma is debated. The aim of the present study is to review our experience with LM/SLNB in a series of patients with thick primary melanoma, to evaluate its utility in this melanoma subset. Patients and methods Thirty patients (18 men and 12 women; mean age 70.6 years; median 75 years) with thick primary melanoma underwent LM/SLNB, using both radioisotope and blue dye. The statistical tests were performed by using SAS software for Windows, version 8.2. Results The primary tumour sites were head/neck (n = 5; 16.6%), trunk (n = 10; 33.3%), and extremities (n = 15; 50%). Tumour thickness ranged from 4 to 17 mm (mean 5.14 mm; median 4.5 mm). Ulceration was observed in 23 (76.6%) tumours. Eleven patients (36.6%) had at least a positive sentinel lymph node (SLN). The mean follow-up was 27.3 months (median 26 months; range 5–63 months). Patients without SLN metastases had a 5-year disease-free survival rate of 78.9%, vs. 18.2% for patients with SLN metastases (P = 0.0121 by log rank test). The 5-year overall survival rate for patients without SLN metastases was 89.5%, whereas patients with SLN metastases had a 5-year overall survival rate of 36.4% (P = 0.0272 by log rank test). Conclusion Our retrospective analysis indicates that the SLN status is predictive of recurrence and survival in patients with thick melanoma, and LM/SLNB should be routinely performed in this subset of melanoma patients.     

Systemic therapy of advanced metastatic malignant melanoma with a combination of fibroblast interferon-beta and recombinant interferon-gamma

Eighteen patients with advanced metastatic malignant melanoma (stage IVUICC 1987) were entered into a prospective trial with a combination of systemic fibroblast interferon-beta and recombinant interferon-gamma. Treatment was performed over a 6-week period with 3 x 5 x 10(6) U i.v. interferon-beta and 5 X 100 micrograms s.c. interferon-gamma every week. Under this therapy 16 patients showed a progressive disease, and 2 patients had a stable disease. The median time of survival was 7.5 months. Successive immunological examinations showed no significant immunomodulating effect after the 6 weeks of interferon treatment. We conclude that the combination of interferon-beta and -gamma is insufficient in the treatment of advanced metastatic malignant melanoma when administered by this dose, route and schedule.