Abstract Objective: To investigate the prognostic factors to developing parotid and neck metastasis in locally advanced and relapsed Cutaneous Squamous Cell Carcinoma (CSCC) of the head and neck region. Methods: Single-center retrospective cohort study enrolling consecutive patients with advanced CSCC from 2009 to 2019. Seventy-four cases were identified. Study variables demographic data, clinical skin tumor stage, neck stage, parotid stage (P stage), surgical treatment features, and parotid, regional, and distant metastases. Survival measures: Overall Survival (OS) and Disease-Specific Survival (DSS). Results: The study group included 72.9% men (median age, 67 years); 67.5% showed T2/T3 tumors, 90.5% comorbidities, 20.2% immunosuppressed, with median follow-up: 35.8 months. The most frequent skin primary were auricular and eyelid regions, 75% underwent primary resection with flap reconstruction. Parotid metastasis was present in 50%, 32.4% showing parotid extracapsular spread, multivariate analysis found OR = 37.6 of positive parotid metastasis evolving into positive neck metastasis, p = 0.001. Occult neck metastasis, neck metastasis, and neck extracapsular spread were observed in 13.5%, 51.3%, and 37.8%, respectively. Kaplan-Meier survival: Clinical T4 versus T1, p = 0.028, P1 stage: 30% and 5% survival at 5 and 10 years, P3 stage: 0%, p = 0.016; OS and DSS showed negative survival for the parotid metastasis group, p = 0.0283. Conclusion: Our outcomes support a surgically aggressive approach for locally advanced and relapsed CSCC, with partial parotidectomy for P0, total parotidectomy for P1–3, selective I–III neck dissection for all patients and adjuvant radiochemotherapy to appropriately treat these patients with advanced CSCC of the head and neck region. Level of evidence: II b – Retrospective Cohort Study – Oxford Centre for Evidence-Based Medicine (OCEBM).

Resumo As cerâmicas porosas podem ser utilizadas nas mais diversas aplicações, como na indústria petroquímica e na área da saúde. No entanto, é difícil produzir cerâmicas com formas complexas usando processos convencionais. Neste trabalho, diferentes termoplásticos (PEBD, ABS e PLA) foram utilizados para a extrusão de filamentos com alumina submicrométrica. Estes filamentos foram extrudados com e sem ácido esteárico que, posteriormente, foram utilizados na manufatura aditiva para a impressão de estruturas porosas (scaffolds) pelo método de fabricação por filamento fundido. Foram obtidas imagens por microscopia eletrônica de varredura das amostras com e sem o ácido esteárico, antes e após a sinterização. Estas imagens mostraram que a presença do ácido esteárico reduziu a formação de defeitos, pois além de atuar como dispersante também facilitou a posterior remoção do veículo orgânico do scaffold, antes da sinterização final.

Abstract Porous ceramics can be used in the most diverse applications, such as in the petrochemical industry and in the health area. However, it is difficult to produce ceramics with complex shapes using conventional processes. In this work, different thermoplastics (LDPE, ABS, and PLA) were used for the extrusion of filaments with submicrometric alumina. These filaments were extruded with and without stearic acid and, subsequently, were used in additive manufacturing for printing porous structures (scaffolds) by fused filament fabrication. Scanning electron microscopy images of the samples with and without stearic acid were obtained before and after sintering. These images showed that the presence of stearic acid reduced the formation of defects since, in addition to acting as a dispersant, it also facilitated the subsequent removal of the organic vehicle from the scaffold, before final sintering.

O processo de moldagem de peças cerâmicas conhecido como colagem de barbotina é um processo antigo, mas que ainda é muito utilizado devido ao seu baixo custo, simplicidade e pelas excelentes propriedades mecânicas das peças sinterizadas. Boas propriedades mecânicas são obtidas quando o pó de partida tem tamanho de partícula submicrométrico. Neste trabalho foram moldadas peças cerâmicas por colagem de barbotina com três aluminas comerciais com partículas submicrométricas e, após a sinterização, foram medidas algumas de suas propriedades, como dureza, densidade e resistência ao desgaste. As barbotinas não flocularam e foram obtidas peças de excelente qualidade, sendo que as peças moldadas com a alumina de menor tamanho de partícula apresentaram a melhor dureza, elevada densidade (chegando a 99% da densidade teórica) e o menor coeficiente de desgaste. Peças de alumina de alta qualidade podem ser usadas em inúmeras aplicações, desde a indústria têxtil até em aplicações biomédicas.

The molding of ceramics parts by slip casting is an ancient process, but it is still very used because of low cost, simplicity and excellent mechanical properties of sintered parts. Better mechanical properties are obtained when the initial powder have small average particle size. In this work, ceramic parts were molded by slip casting of three commercial submicrometer-sized alumina powders. After sintering, some properties of these ceramic parts were measured, including hardness, density and wear coefficient. The slips do not flocullate, resulting in ceramic parts with excellent quality. Ceramic parts made with the alumina powder of smaller particle size exhibited high hardness, high density (99% TD) and lower wear coefficient. High quality alumina parts such as that produced in this work can be used in many applications, from textile industry to biological applications.