Gut Microbiota Imbalance in Metastatic Colorectal Patients Treated With EGFRI and Long-Term Antibiotic Therapy for Cutaneous Toxicity: A Pilot Study.

Patients with metastatic colorectal cancer (mCRC) frequently experience epidermal growth factor inhibitors (EGFRI)-induced skin side effects. Antibiotic treatment with doxycycline is often required in order to manage the skin and mucosal toxicity. Since these patients already have significant gut dysbiosis, the long-term antibiotic treatment may destabilize their gut microbiome. Objectives The assessment of intestinal dysbiosis in patients undergoing treatment with EGFRI, who require antibiotic treatment with doxycycline in order to manage adverse skin effects. Methods We conducted a prospective pilot study between 2020 and 2021 involving 10 patients with mCRC. These patients were undergoing treatment with EGFRI and required either short-term or long-term treatment with doxycycline in order to manage skin toxicity. Results The patients with mCRC who were treated with doxycycline for 8 weeks showed overexpression of Escherichia coli, Candida, and Geotrichum species compared to the patients who only received doxycycline treatment for two weeks. Conclusions The elevated levels of Escherichia coli and Candida species in the patients who received doxycycline for eight weeks compared to the patients who received the treatment for two weeks could provide a starting point for the development of a standardized guideline regarding the use of pre-active or reactive antibiotic treatment. We also highlight the importance of analyzing the intestinal microbiome of these patients. The identification of overexpressed species, as well as the deficiency of certain protective species, could guide the administration of probiotics to cover and repair the affected intestinal flora.

Cutaneous Toxicity in Oncologic Patients Receiving Epidermal Growth Factor Receptor Inhibitors.

BACKGROUND: In recent years, oncology studies have focused on molecular targeted therapy, based on the development of numerous agents with a role in inhibiting the epidermal growth factor receptor (EGFR). When overexpressed, EGFR plays an extremely important role in the growth of certain tumour cells. Compared to classical chemotherapy, the systemic adverse effects of the molecular targeted therapy are much lower. However, between 80 to 100% of the patients treated with EGFR inhibitors develop a separate class of adverse effects, namely skin reactions. OBJECTIVES: Early identification of skin toxicity, dynamic monitoring of patients during EGFRI treatment, correlation of clinical data and their management. METHODS: We conducted a prospective study from 2018 to 2021 on patients who had received any EGFRI from all over Oltenia region. We were able to identify 31 oncologic patients who had received EGFRI for metastatic colorectal cancer, lung cancer or head and neck cancer. All of them were completely dermatologically examined, dynamically monitored for each oncological cycle. RESULTS: The dermatological follow-up throughout the study allowed the classification of skin toxicity according to the onset of manifestations after EGFRI treatment, the reporting of serious adverse effects and their management. Within the study group, 29 out of the 31 patients treated oncological with EGFRI therapy experienced at least one cutaneous adverse effect, the majority of which showed clinical polymorphism of lesions. CONCLUSIONS: The lack of dermatological treatment often leads to dose reduction or even to the discontinuation of the cancer treatment. Severe forms were also identified and their rapid treatment allowed the continuation of the cancer therapy and increased quality of life for all patients.

Role of modern imaging techniques for the in vivo diagnosis of lichen planus.

Lichen planus (LP) is a chronic inflammatory skin disease that can sometimes affect mucosal surfaces, with unknown pathogenesis, even though it appears to be an autoimmune disease. The diagnosis of lichen planus is usually based on histopathological examination of the lesions. Nowadays, the classical invasive diagnostic methods are replaced by modern non-invasive techniques. In this review, we present the main non-invasive imaging methods (dermoscopy, reflectance confocal microscopy, optical coherence tomography, ultrasound and diffuse reflection spectrophotometry) used in the diagnosis and therapeutic monitoring of lichen planus. Dermoscopy is a non-invasive method initially used for diagnosis of pigmented tumors but now is used also for inflammatory and infectious skin diseases. In lichen planus, the dermoscopy increases the accuracy of diagnosis, avoids skin biopsies commonly used and can be useful in the therapeutic monitoring by repeated investigation at different stages of treatment. Reflectance confocal microscopy (RCM) is a novel non-invasive imaging technique that is prevalently used for the diagnosis of skin tumors and inflammatory skin diseases. This technology has been mostly employed for bedside, real-time microscopic evaluation of psoriasis, lichen planus, contact dermatitis, revealing specific confocal features to support clinical diagnosis and assist with patient management. Optical coherence tomography (OCT) is an emergent imaging technique, developed over the last decade, based on the interaction of the infrared radiation (900-1,500 nm) and the living tissues. A limited information exists on the benefits of OCT technology for the in vivo diagnosis of LP but could be a useful auxiliary tool in the in vivo differential diagnosis, especially in clinical equivocal settings like mucosal lesions, and in monitoring the response to treatment. Our review shows the possibility of using modern imaging techniques for the in vivo diagnosis and also for evaluation of the treatment response.