Background: squamous cell carcinoma (SCC) is the second most common type of malignancy worldwide. Skin and mucosa of the head and neck areas are the most frequently affected. An aggressive behavior in SCC is not easily detected, and despite all efforts, mortality in these types of cancer did not show major improvements during recent decades. In this study, we aim to determine the role of histological features available through standard pathology assessment in SCC and their relation with tumor behavior and patients’ survival. Method: in a group of one hundred patients diagnosed with SCC involving the head and neck areas, we assessed the presence of four histological features (tumor/stroma ratio, immune infiltration at the front of invasion, tumor-budding activity, and tumor necrosis), their correlations with tumor type (mucosal or cutaneous), tumor clinicopathological characteristics, and their prognostic potential. Results: the comparison between histological features in cutaneous versus mucosal SCC reveals no significant differences for any of the four parameters assessed. We found significant correlations between tumor/stroma ratio and lymphatic metastasis (p = 0.0275), perineural invasion (p = 0.0006), and clinical staging (p = 0.0116). Immune infiltration at the front of invasion revealed similar correlations with lymph node involvement (p = 0.002), perineural invasion (p = 0.0138), and clinical staging (p = 0.0043). Tumor budding and tumor necrosis correlated with the size of the tumor (p = 0.0077 and p = 0.0004) and the clinical staging (p = 0.0039 and p = 0.0143). In addition, tumor budding was significantly correlated with perineural invasion (p = 0.0454). In mucosal SCC, patients with improved outcome revealed high values for the tumor/stroma ratio (p = 0.0159) and immune infiltration at the front of invasion (p = 0.0274). However, the multivariate analysis did not confirm their independent prognostic roles. Conclusions: extended histological assessments that include features such as tumor/stroma ratio, immune infiltration at the front of invasion, tumor budding, and tumor necrosis can be an easy, accessible method to collect additional information on tumor aggressiveness in skin and mucosa SCC affecting the head and neck areas.

Background and aims. Multiple sclerosis is a disease of the central nervous system, whose treatment often involves the use of monoclonal antibodies. This can lead to a series of complications that the clinician should pay attention to and accordingly adjust the therapy. We aim to emphasize real-life experiences with adverse cutaneous reactions to monoclonal antibodies by presenting a series of two cases from our clinic. Methods. In the first case, a female patient was treated with natalizumab for eight years and developed relapsing-remitting cutaneous lesions following the monthly administration of the treatment. The second case is of a male patient treated with ocrelizumab, who developed plaque-like lesions following the fifth administration. We analyzed the biological parameters and performed investigations, dermatological evaluation and skin biopsies. Results. The result of the skin biopsy for the natalizumab patient showed a chronic spongiotic dermatitis, with the anti-natalizumab antibodies being negative. The patient who received ocrelizumab developed nummular eczema, disseminated on his trunk and limbs. Conclusions. Given the fact that these therapies are frequently used in multiple sclerosis patients, and their skin adverse reactions are known, we described some particularities and a brief review of the literature with practical implications. Further studies need to be conducted to establish a firm association between monoclonal antibodies therapy and adverse cutaneous reactions, but the clinician should be aware of their existence.