Impact of Fat Graft Thickness and Harvesting Technique on Adipocyte Viability in a New Porcine Experimental Model: An Immunohistochemical Analysis.

BACKGROUND: Autologous fat grafting (AFG) has been employed in surgical practice as a filling method. However, controversies remain on the specifics of this technique. So far, few relevant experimental large animal studies have objectively assessed factors related to AFG integration. OBJECTIVES: This study utilized an experimental, medium-sized animal model to compare the feasibility of AFG collected employing 2 different techniques with instruments of distinct thicknesses. METHODS: Twenty minipigs (Sus scropha domesticus) were subjected to AFG harvesting via en bloc resection utilizing 3- (Group I) and 5-mm-diameter (Group II) round punch blades (PBs) and liposuction (LS) with 3- (Group III) and 5-mm-diameter cannulas (Group IV). Both samples were grafted intramuscularly (biceps femoralis). Hematoxylin and eosin staining was employed to identify intact adipocytes, fat necrosis, fibrosis, inflammation, and oil cysts. Immunohistochemical staining (perilipin-A, tumor necrosis factor alfa, and cluster of differentiation number 31) was utilized to quantify the feasibility of adipocytes, tissue necrosis, and neoangiogenesis, respectively. RESULTS: Hematoxylin and eosin analysis showed that fat necrosis and histiocyte presence were significantly lower in the AFG harvested utilizing a PB than in LS. For perilipin-A, a statistical difference was observed between subgroups I and III (P = 0.001) and I and IV (P = 0.004). Instrument diameter had no effect on graft integration in comparisons between groups II and III (P = 0.059) and II and IV (P = 0.132). CONCLUSIONS: In this experimental study, fat collected utilizing a PB demonstrated higher adipocyte viability than fat collected with LS. The diameter of the collection instruments, whether PB or LS, had no effect on graft integration.

Influence of vascularized lymph node transfer (VLNT) flap positioning on the response to breast cancer-related lymphedema treatment. / Influência do posicionamento do retalho linfonodal vascularizado na resposta ao tratamento cirúrgico do linfedema secundário ao câncer de mama.

OBJECTIVE: to evaluate the initial therapeutic experience of transplantation of vascularized lymph nodes in patients with lymphedema of the upper limbs secondary to the treatment of breast cancer, and to verify if the positioning of the transplant influences the surgical result. METHODS: we conducted a prospective, comparative test of two therapeutic modalities, with 24 patients with lymphedema of the upper limb after breast cancer treatment, classified as grades 2 and 3, according to the International Lymphedema Society. The two types of procedures performed were: 1) total breast reconstruction with - deep inferior epigastric perforator (DIEP) flap associated with lymph node flap, in patients with no previous breast reconstruction or loss of previous reconstruction (axillary positioning); 2) isolated inguinal lymph node flap performed in patients with completed breast reconstruction or without the desire to perform the breast reconstruction (wrist positioning). RESULTS: the reduction percentage of the affected limb volume was 20.1% (p=0.0370). The number of infectious episodes (cellulites) also decreased significantly, from 41% in the preoperative period to 12.5% in the postoperative one (p=0.004). There were no differences between the proximal and distal groups. CONCLUSION: the transplantation of lymph nodes positively affected the postoperative evolution of patients with lymphedema secondary to breast cancer. We observed no differences in relation to flap positioning.

OBJETIVO: analisar a experiência terapêutica inicial do transplante de linfonodos vascularizados em pacientes portadoras de linfedema de membros superiores secundário ao tratamento do câncer de mama e verificar se o posicionamento do transplante influencia o resultado cirúrgico. MÉTODOS: ensaio prospectivo, comparativo, de duas modalidades terapêuticas em 24 pacientes portadoras de linfedema de membro superior após tratamento de câncer mamário, classificados como graus 2 e 3, segundo a Sociedade Internacional de Linfedema. Os dois tipos de procedimentos realizados foram: 1) reconstrução total da mama com retalho de perfurante da artéria epigástrica inferior (DIEP- deep inferior epigastric perforator flap) associado ao retalho linfonodal, em pacientes sem reconstrução mamária prévia ou com histórico de perda da reconstrução (posicionamento axilar); 2) retalho linfonodal inguinal isolado foi realizado em pacientes com reconstrução mamária finalizada ou sem o desejo de realizar a reconstrução da mama (posicionamento no punho). RESULTADOS: a porcentagem de redução do volume do membro afetado foi de 20,1% (p=0,0370). O número de episódios infecciosos (celulites) também sofreu redução significativa, de 41% no período pré-operatório para 12,5% no pós-operatório (p=0,004). Não foram observadas diferenças entre os grupos proximal e distal. CONCLUSÃO: o transplante de linfonodos afetou positivamente a evolução pós-operatória de pacientes portadoras de linfedema secundário ao câncer de mama. Não foram observadas diferenças em relação ao posicionamento do retalho.

Influência do posicionamento do retalho linfonodal vascularizado na resposta ao tratamento cirúrgico do linfedema secundário ao câncer de mama / Influence of vascularized lymph node transfer (VLNT) flap positioning on the response to breast cancer-related lymphedema treatment

RESUMO Objetivo: analisar a experiência terapêutica inicial do transplante de linfonodos vascularizados em pacientes portadoras de linfedema de membros superiores secundário ao tratamento do câncer de mama e verificar se o posicionamento do transplante influencia o resultado cirúrgico. Métodos: ensaio prospectivo, comparativo, de duas modalidades terapêuticas em 24 pacientes portadoras de linfedema de membro superior após tratamento de câncer mamário, classificados como graus 2 e 3, segundo a Sociedade Internacional de Linfedema. Os dois tipos de procedimentos realizados foram: 1) reconstrução total da mama com retalho de perfurante da artéria epigástrica inferior (DIEP- deep inferior epigastric perforator flap) associado ao retalho linfonodal, em pacientes sem reconstrução mamária prévia ou com histórico de perda da reconstrução (posicionamento axilar); 2) retalho linfonodal inguinal isolado foi realizado em pacientes com reconstrução mamária finalizada ou sem o desejo de realizar a reconstrução da mama (posicionamento no punho). Resultados: a porcentagem de redução do volume do membro afetado foi de 20,1% (p=0,0370). O número de episódios infecciosos (celulites) também sofreu redução significativa, de 41% no período pré-operatório para 12,5% no pós-operatório (p=0,004). Não foram observadas diferenças entre os grupos proximal e distal. Conclusão: o transplante de linfonodos afetou positivamente a evolução pós-operatória de pacientes portadoras de linfedema secundário ao câncer de mama. Não foram observadas diferenças em relação ao posicionamento do retalho.

ABSTRACT Objective: to evaluate the initial therapeutic experience of transplantation of vascularized lymph nodes in patients with lymphedema of the upper limbs secondary to the treatment of breast cancer, and to verify if the positioning of the transplant influences the surgical result. Methods: we conducted a prospective, comparative test of two therapeutic modalities, with 24 patients with lymphedema of the upper limb after breast cancer treatment, classified as grades 2 and 3, according to the International Lymphedema Society. The two types of procedures performed were: 1) total breast reconstruction with - deep inferior epigastric perforator (DIEP) flap associated with lymph node flap, in patients with no previous breast reconstruction or loss of previous reconstruction (axillary positioning); 2) isolated inguinal lymph node flap performed in patients with completed breast reconstruction or without the desire to perform the breast reconstruction (wrist positioning). Results: the reduction percentage of the affected limb volume was 20.1% (p=0.0370). The number of infectious episodes (cellulites) also decreased significantly, from 41% in the preoperative period to 12.5% in the postoperative one (p=0.004). There were no differences between the proximal and distal groups. Conclusion: the transplantation of lymph nodes positively affected the postoperative evolution of patients with lymphedema secondary to breast cancer. We observed no differences in relation to flap positioning.

Qualitative analysis of the viability of autogenous fat grafts grafted in different environments of interstitial pressure. Preliminary results and description of a new experimental model in mini-pigs.

PURPOSE: To evaluate the feasibility of an experimental model of autologous fat graft (AFG) in different interstitial pressure (IP) environments. METHODS: Three mini-pigs(Minipig-BR) with age of 8 months (weight: 25-30 kg) were used. AFG were collected from the bucal fat pad, and grafted in the intramuscular pocket (biceps femoralis muscle). IP model was based on a fusiform ressection followed by primary closure "under tension". A blood pressure catheter located in the intramuscular region connected to a pressure module was applied to quantify IP. RESULTS: The mean operative time was 236 min (210 - 272 min). All the AFG and muscular segments were removed successfully. Average interstitial pressure CP and H were 3 and 10.6 mmHg respectively. The AFG were biopsied for histopathological analysis 30 days after graft. Hematoxylin-eosin staining and immunohistochemical analyzes (TNF-alpha, CD31 and Perilipine with monoclonal antibodies) were employed. CONCLUSION: The data show that minipigs model could be used as a recipient site for autologous fat graft techniques and allow the development of studies to explore the AFG intake and pathophysiology response.

Qualitative analysis of the viability of autogenous fat grafts grafted in different environments of interstitial pressure. Preliminary results and description of a new experimental model in mini-pigs

Abstract Purpose: To evaluate the feasibility of an experimental model of autologous fat graft (AFG) in different interstitial pressure (IP) environments. Methods: Three mini-pigs(Minipig-BR) with age of 8 months (weight: 25-30 kg) were used. AFG were collected from the bucal fat pad, and grafted in the intramuscular pocket (biceps femoralis muscle). IP model was based on a fusiform ressection followed by primary closure "under tension". A blood pressure catheter located in the intramuscular region connected to a pressure module was applied to quantify IP. Results: The mean operative time was 236 min (210 - 272 min). All the AFG and muscular segments were removed successfully. Average interstitial pressure CP and H were 3 and 10.6 mmHg respectively. The AFG were biopsied for histopathological analysis 30 days after graft. Hematoxylin-eosin staining and immunohistochemical analyzes (TNF-alpha, CD31 and Perilipine with monoclonal antibodies) were employed. Conclusion: The data show that minipigs model could be used as a recipient site for autologous fat graft techniques and allow the development of studies to explore the AFG intake and pathophysiology response.

Avaliação do índice de infecção de implantes mamários utilizados na reconstrução de mama do Instituto do Câncer do Estado de São Paulo / Evaluation of the infection rate of implants used for breast reconstruction at the Cancer Institute of the State of São Paulo

INTRODUÇÃO: A utilização de implante mamário é a forma de reconstrução de mama mais comumente realizada. Apesar de suas vantagens, a infecção do implante, seja este expansor tecidual ou prótese mamária, pode ser um problema significativo, incluindo a necessidade de sua retirada. O objetivo deste trabalho é avaliar o índice de infecção de implantes mamários utilizados na reconstrução de mama de pacientes operadas no Instituto do Câncer do Estado de São Paulo (ICESP), bem como sua correlação com aspectos clínicos, oncológicos e cirúrgicos. PACIENTES E MÉTODOS: Estudo retrospectivo de 120 pacientes submetidas à reconstrução mamária com implante mamário no ICESP, no período de fevereiro de 2009 a março de 2010. RESULTADOS: O índice de infecção foi de 24,3% e esteve relacionado estatisticamente a reconstrução imediata (88,9%), diabetes mellitus (25%), IMC acima de 30 (52,8%), HAS (52,8%) e sofrimento de pele da mastectomia (27,8%). Nota-se que 44% dos implantes infectados foram retirados, sendo a maioria expansores colocados em reconstrução imediata. CONCLUSÕES: A reconstrução mamária com implante é uma forma segura e eficaz de tratamento. Deve-se, entretanto, estar atento aos subgrupos de pacientes mais propensas ao desenvolvimento de infecção, para otimizar a sua prevenção e atentar ao seu tratamento precoce.

INTRODUCTION: Placement of breast implants is the most commonly used form of breast reconstruction. Despite its advantages, infection of the implant, either in the tissue expander or mammary prosthesis, can be a significant problem, including the need to remove it. The objective of this work is to evaluate the infection rate of breast implants used for breast reconstruction in patients submitted to surgery at the Cancer Institute of the State of São Paulo (ICESP), as well as its correlation with clinical, oncological, and surgical factors. PATIENTS AND METHODS: This is a retrospective study on 120 patients submitted to breast reconstruction with breast implants at the ICESP from February 2009 to March 2010. RESULTS: The infection rate (24.3%) was statistically related to immediate reconstruction (88.9%), diabetes mellitus (25%), body mass index >30 (52.8%), systemic arterial hypertension (52.8%), and skin injury due to mastectomy (27.8%). Of the infected implants, 44% were removed, most of which were expanders placed during immediate reconstruction. CONCLUSIONS: Breast reconstruction with implants is the safest and most effective form of treatment. However, consideration should be given to patients who are prone to the development of infection, in order to optimize its prevention and attempt to perform its treatment at an early stage.