TOXICAN: a guide for grading dermatological adverse events of cancer treatments

PURPOSE

The dermatological toxicity of cancer treatments is frequent and sometimes debilitating. Its reference classification, the NCI-CTCAE (National Cancer Institute-Common Terminology Criteria for Adverse Events), is sometimes difficult to use and does not include yet the newest toxicities. Our objective was to create a guide, TOXICAN, based on the CTCAE, which is easy to use in everyday practice and which facilitates the recognition and grading of these dermatological toxicities.

METHODS

This guide was developed by a working group ("GESTIM") comprising oncodermatologists, allergists, pathologists, and researchers from Nantes University Hospital. It was based on the dermatological toxicities found in the CTCAE and adapted to daily practice. These toxicities were grouped into categories and associated with photographs of typical cases to aid recognition. A simplified grading scale derived from the CTCAE was also created. This booklet was validated by means of user evaluation, and then the Delphi consensus method.

RESULTS

We selected 32 dermatological toxicities, including 12 created by our group, sorted into 7 categories: skin rash, dry skin/pruritus, hyperkeratotic papules, palmoplantar changes, hair and nail changes, mucosal changes, and others. Our simplified grading scale only differed from the CTCAE for one item, urticaria. Three items were modified after evaluation by the user group and 11 after application of the Delphi method.

CONCLUSION

The objective of our practical guide is to facilitate the use of the CTCAE for recognizing and grading dermatological toxicity of cancer treatments in order to provide optimal guidance for therapeutic adaptations. Its impact on clinical practice remains to be evaluated.

Profile of vemurafenib-induced severe skin toxicities

BACKGROUND

Vemurafenib, a BRAF inhibitor, is commonly associated with skin toxicity. The impact of severe forms is unknown.

OBJECTIVE

To determine the rate of permanent vemurafenib discontinuation due to grade 3-4 skin toxicity, features of these toxicities, their recurrence rate after a switch to dabrafenib and their impact on overall survival.

METHODS

Retrospective cohort study of 131 patients treated with vemurafenib for melanoma between November 2010 and December 2014. Data on skin toxicities, the need for vemurafenib adjustment and the impact of switching to dabrafenib were collected. Regarding survival analysis, a conditional landmark analysis was performed to correct lead-time bias.

RESULTS

Among the 131 vemurafenib-treated patients, 26% developed grade 3-4 skin toxicity. Forty-four percent of them permanently discontinued their treatment, mainly due to rash and classic skin adverse reactions (Steven-Johnson syndrome, Drug Reaction with Eosinophilia and Systemic Symptoms). Conversely, photosensitivity and carcinomas rarely required treatment adjustment. Grade 3-4 rashes were associated with clinical or biological abnormalities in 94% of patients. Among the 10 patients who subsequently switched to dabrafenib, skin toxicity recurred only in one patient. Overall survival was significantly prolonged in case of severe skin toxicity emerging within the first 4 (P = 0.014) and 8 weeks (P = 0.038) on vemurafenib, with only a trend at 12 weeks (P = 0.052). Median overall survival was also prolonged in case of severe rash.

CONCLUSION

In this study, vemurafenib was continued in 56% of patients with grade 3-4 skin toxicity, which was associated with prolonged overall survival when emerging within the first 4 and 8 weeks of treatment. While developing severe skin adverse reactions permanently contraindicates vemurafenib use, other rashes should lead to retreatment attempts with dose reduction. In case of recurrence, dabrafenib seems to be an interesting option. For other skin toxicities, including photosensitivity and cutaneous carcinoma, treatment adjustment is usually not needed.

Development of brain metastases in patients with metastatic melanoma while receiving ipilimumab

Ipilimumab is a monoclonal antibody blocking the inhibitory molecule CTLA4 expressed by activated T lympocytes, used for the treatment of metastatic melanoma. Recent studies have shown its potential efficacy on brain metastases.

OBJECTIVES

To assess the development of brain metastases under ipilimumab and identify clinical, histological or evolving criteria related to the appearance of these metastases. A retrospective study was conducted in 52 patients treated with 4 cycles of ipilimumab 3 mg/kg every 3 weeks for unresectable stage III or stage IV melanoma between January 2011 and July 2013 in a Department of Dermato-Oncology. As no data has been find in the literature, the results were compared to our other cohort of patients treated with vemurafenib during the same period. Ten patients (21.7 %) developed brain metastases under ipilimumab in a median time of 6.58 months after treatment initiation. The multivariate analysis showed a lower rate of brain metastases in patients with acral lentiginous melanoma and melanoma of unknown primary site. The median survival after diagnosis of brain metastases was of 2.5 months. There was no significant difference with vemurafenib-treated patients in terms of incidence rate of brain metastasis, time of development and survival after diagnosis of cerebral metastases. This was the first study focused on the development of brain metastases under treatment with ipilimumab 3 mg/kg. Although ipilimumab is used for the treatment of brain metastases, it paradoxically did not seem to reduce the risk of developing brain metastases.

Development of squamous cell carcinoma into basal cell carcinoma under treatment with Vismodegib

BACKGROUND

Basal cell carcinoma (BCC) is the most common cancer in humans. Vismodegib, a Hedgehog pathway inhibitor, has proved its effectiveness in treating non-resectable advanced BCC.

AIM

However, its action on squamous cell carcinoma (SCC) is unknown. We present three SCC cases developed into BCC in vismodegib-treated patients.

MATERIAL AND METHODS

We have described three cases of patients developing SCC during treatment by vismodegib for BCC.

RESULTS

Patient 1 was treated with vismodegib for five facial BCC. Due to the progression of one of the lesions at month 3 (M3), a biopsy was performed and showed SCC. Patient 2 was treated with vismodegib for a large facial BCC. A biopsy was performed at M2 on a BCC area not responding to treatment and showed SCC. Patient 3 was treated with vismodegib for a BCC on the nose. Due to vismodegib ineffectiveness, a biopsy was performed and showed SCC.

DISCUSSION

Two similar cases have been described in the literature. This could be due to the appearance of the squamous contingent of a metatypical BCC or to the squamous differentiation of stem cells through inhibition of the hedgehog pathway.

CONCLUSION

In practice, any dissociated response of a BCC to vismodegib should be biopsied.

Melanoma and rituximab: an incidental association?

Rituximab is an anti-CD20 monoclonal antibody increasingly used in haematology and rheumatology, but also in internal medicine and dermatology. It has a good tolerance profile without known increased risk of cancer. We report a case of nodular melanoma with a 4.8 mm Breslow thickness that appeared after 2 years of rituximab in a 45-year-old patient with non-Hodgkin lymphoma. Fifteen additional rituximab-associated melanoma cases in 13 patients have been identified in the literature and in the EudraVigilance database. These patients were treated for various indications and had melanomas, often aggressive, initially diagnosed at a metastatic stage in 31% of cases. Our work raises the question of rituximab accountability in melanoma onset in these immunosuppressed patients. A dermatological monitoring seems necessary in patients treated with rituximab, especially in case of risk factors for melanoma. In case of individual melanoma history, the benefit/risk ratio of initiating rituximab therapy should be carefully assessed.