Dabrafenib-associated necrobiotic granulomatous reaction

Review BRAF inhibition and the spectrum of granulomatous reactions

BRAF-inhibitors have emerged as a promising targeted therapy for malignancies with BRAF mutations, particularly metastatic melanoma. However, granulomatous reactions including sarcoidosis and sarcoid-like-reactions have been reported as a consequence of BRAF-inhibition. It is important to adequately characterise these granulomatous reactions including cutaneous manifestations and systemic involvement, in order to guide investigations and management. A literature review was conducted to characterise the spectrum of granulomatous reactions associated with BRAF-inhibitors - identifying 55 reactions affecting 51 patients, with 37 reactions limited to cutaneous involvement. Further, possible correlation with cancer response, mechanisms of granuloma formation, as well as a proposed workup and management approach for these granulomatous reactions are presented.

Diverse landscape of dermatologic toxicities from small-molecule inhibitor cancer therapy

BACKGROUND

Advances in molecular biology and genetics have contributed to breakthrough treatments directed at specific pathways associated with the development of cancer. Small-molecule inhibitors (Nibs) aimed at a variety of cellular pathways have been efficacious; however, they are associated with significant dermatologic toxicities.

METHODS

We conducted a comprehensive review of dermatologic toxicities associated with Nibs categorized into the following five groups: (a) mitogen-activated protein kinase; (b) growth factor/multi-tyrosine kinase; (c) cell division/DNA repair; (d) signaling associated with myeloproliferative neoplasms; and (e) other signaling pathways. Prospective phase I, II, or III clinical trials, retrospective literature reviews, systematic reviews/meta-analyses, and case reviews/reports were included for analysis.

RESULTS

Dermatologic toxicities reviewed were associated with every class of Nibs and ranged from mild to severe or life-threatening adverse skin reactions. Inflammatory reactions manifesting as maculopapular, papulopustular/acneiform, and eczematous lesions were frequent types of dermatologic toxicities seen with Nibs. Squamous cell carcinoma with keratoacanthoma-like features was associated with a subset of Nibs. Substantial overlap in dermatologic toxicities was found between Nibs.

CONCLUSIONS

Dermatologic toxicities from Nibs are diverse and may overlap between classes of Nibs. Recognition of the various types of toxicities from Nibs is critical for patient care in the era of "oncodermatology/dermatopathology."

MAPK blockade, toxicities, pathogenesis and management

PURPOSE OF REVIEW

BRAF/MEK inhibitor has changed the treatment landscape in patients with advanced and metastatic melanoma with prolonged overall survival and progression-free survival. Since three treatment combinations exist with similar efficacy therapy decisions are often made based on the side effect profile. Additionally, on-target side effects or class effects have to be properly managed to ensure treatment adherence.

RECENT FINDINGS

Sequential treatment with BRAF/MEK inhibition and immunotherapy might increase toxicity with a sepsis-like syndrome and triple therapy with concomitant BRAF/MEK inhibition and anti-PD1/PD-L1 antibody therapy induces severe side effects in the vast majority of patients.

SUMMARY

Toxicity of combination therapy with BRAF/MEK inhibitors is generally manageable, reversible and infrequently associated with treatment discontinuation. In case of persisting off-target effects the change to another combination therapy can resolve side effects.

Granulomatous Cutaneous Drug Eruptions: A Systematic Review

BACKGROUND

Granulomatous drug eruptions are rare entities, where granuloma formation occurs as an attempt to contain an exogenous or endogenous inciting agent. Granulomatous drug eruptions may be localized to the skin or may include major systemic involvement, and their characteristics depend both on the properties of the causative irritant and host factors. Because of the overlapping features amongst noninfectious granulomatous diseases, granulomatous drug eruptions are challenging to diagnose and distinguish both histologically and clinically.

OBJECTIVE

The objective of this article is to provide a review and summary of the current literature on the five major types of cutaneous granulomatous drug eruptions: interstitial granulomatous drug reaction, drug-induced accelerated rheumatoid nodulosis, drug-induced granuloma annulare, drug-induced sarcoidosis, and miscellaneous presentations.

METHODS

A systematic review was conducted through PubMed using the search terms "granulomatous drug eruption" and "cutaneous" or "skin". English full-text studies that included human subjects experiencing a cutaneous reaction comprising granulomatous inflammation as the direct result of a drug were included. Of 205 studies identified, 48 articles were selected after a full-text review. Evidence was evaluated using the Tool for evaluating the methodological quality of case reports and case series.

RESULTS

Polypharmacy and a prolonged lag period from drug ingestion to rash onset may create diagnostic challenges. Ruling out tuberculosis is imperative in the endemic setting, particularly where anti-tumor necrosis factor therapy is the presumed cause. Interstitial granulomatous drug reactions and granuloma annulare are often localized to the skin whereas accelerated rheumatoid nodulosis and sarcoidosis may sometimes be associated with systemic features as well. Granulomatous drug eruptions typically resolve on discontinuing the offending medication; however, the decision for drug cessation is dependent on a risk-benefit assessment. In some situations, supplementation of an additional agent to suppress the reaction may resolve symptoms. In some cases, granulomatous drug eruptions may be pivotal in the successful outcome of the drug, as in cases of melanoma treatment. In all situations, the decision to continue or withdraw the drug should be carefully based on the severity of the eruption, necessity of continuing the drug, and availability of a suitable alternative.

CONCLUSIONS

Granulomatous drug eruptions should always be considered in the differential diagnosis of noninfectious granulomatous diseases of the skin. Further research examining dose-response relationships and the recurrence of granulomatous drug eruptions on the rechallenge of offending agents is required. Increased awareness of granulomatous drug eruption types is important, especially with continuous development of new anti-cancer agents that may induce these reactions.

CLINICAL TRIAL REGISTRATION

PROSPERO registration number CRD42020157009.

Drug-Induced Sarcoidosis-Like Reactions

A drug-induced sarcoidosis-like reaction (DISR) is a systemic granulomatous reaction that is indistinguishable from sarcoidosis and occurs in a temporal relationship with initiation of an offending drug. DISRs typically improve or resolve after withdrawal of the offending drug. Four common categories of drugs that have been associated with the development of a DISR are immune checkpoint inhibitors, highly active antiretroviral therapy, interferons, and tumor necrosis factor-α antagonists. Similar to sarcoidosis, DISRs do not necessarily require treatment because they may cause no significant symptoms, quality of life impairment, or organ dysfunction. When treatment of a DISR is required, standard antisarcoidosis regimens seem to be effective. Because a DISR tends to improve or resolve when the offending drug is discontinued, this is another effective treatment for a DISR. However, the offending drug need not be discontinued if it is useful, and antigranulomatous therapy can be added. In some situations, the development of a DISR may suggest a beneficial effect of the inducing drug. Understanding the mechanisms leading to DISRs may yield important insights into the immunopathogenesis of sarcoidosis.