Diego Daniel Pereira

Absence of Lymph Nodes in the Resected Specimen After Radical Surgery for Distal Rectal Cancer and Neoadjuvant Chemoradiation Therapy: What does it Mean?

PurposeThe number of retrieved lymph nodes during radical surgery has been considered of great importance to ensure adequate staging and radical resection. However, this finding may not be applicable after neoadjuvant therapy in which, not only is there a decrease in lymph nodes recovered, but also a subgroup of patients with absence of lymph nodes in the resected specimen.MethodsPatients with absence of lymph nodes were compared with patients with ypN0 disease and patients with ypN+ disease.ResultsThirty-two patients (11 percent) had absence of lymph nodes, 171 patients (61 percent) had ypN0 disease, and 78 patients (28 percent) had ypN+ disease. Patients with absence of lymph nodes had significantly lower ypT status (ypT0-1, 40 vs. 13 percent; P < 0.001) and decreased risk of perineural invasion (6 vs. 21 percent; P = 0.04) compared with ypN0 patients. Five-year disease-free survival (74 percent) was similar to patients with ypN0 (59 percent; P = 0.2), and both were significantly better than patients with ypN+ disease (30 percent; P < 0.001).ConclusionsAbsence of lymph nodes retrieved from the resected specimen is associated with favorable pathologic features (ypT and perineural invasion status) and good disease-free survival rates. In this setting, absence of retrieved lymph nodes may reflect improved response to neoadjuvant chemoradiation therapy rather than inappropriate or suboptimal oncologic radicality.

Lymph node size in rectal cancer following neoadjuvant chemoradiation--can we rely on radiologic nodal staging after chemoradiation?

OBJECTIVES: Local excision is currently being considered as an alternative strategy for ypT0-2 rectal cancer. However, patient selection is crucial to rule out nodal disease and is performed by radiologic studies that consider size as a surrogate marker for positive nodes. The purpose of this study was to determine the difference in size between metastatic and nonmetastatic nodes and the critical lymph node size after neoadjuvant chemoradiation therapy. METHODS: The 201 lymph nodes available from 31 patients with ypT0-2 rectal cancer were reviewed and measured. Lymph nodes were compared according to the presence of metastases and size. RESULTS: There was a mean of 6.5 lymph nodes per patient and 12 positive nodes of the 201 recovered (6%). Ninety-five percent of all lymph nodes were <5 mm, whereas 50% of positive lymph nodes were <3 mm. Metastatic lymph nodes were significantly greater in size (5.0 vs. 2.5mm; P = 0.02). Lymph nodes >4.5 mm had a greater risk of harboring metastases (P = 0.009). CONCLUSIONS: Patients with ypT0-2 rectal cancer following neoadjuvant chemoradiation have very small perirectal nodes. Individual metastatic lymph nodes are significantly larger. However, a significant number of lymph nodes after neoadjuvant chemoradiation (negative and positive) are <3 mm. Individual lymph node size is not a good predictor of nodal metastases and may lead to inaccurate radiologic staging.

Mucinous colorectal adenocarcinoma : influence of mucin expression (Muc1, 2 and 5) on clinico-pathological features and prognosis

BackgroundMucinous component is associated with distinct clinical and pathological features and poor survival in colorectal cancer. The purpose of this study was to determine differences in outcomes of patients with mucinous colorectal adenocarcinoma according to the type of mucin expressed.Materials and MethodsImmunohistochemistry was performed in all tumors of patients who underwent radical surgery between 1998 and 2003 with mucinous colorectal cancer using antibodies against MUC1, 2, and 5. Correlation between immunoexpression and clinical, pathological features and survival was performed.ResultsOf the 418 patients treated in this period, only 35 had a mucinous adenocarcinoma. Of these, 25 were positive for 1 or more mucin expression. MUC2 expression correlated with tumor site and depth of penetration, while MUC5 expression correlated to tumor site. Overall survival was significantly worse for patients with MUC2 expression, and disease-free survival was significantly worse for patients with MUC1 expression.ConclusionsMucin expression may have significant correlation to specific clinical-pathological features and survival of patients with mucinous-type colorectal adenocarcinoma. These differences may reflect distinct molecular mechanisms involved in carcinogenesis of mucinous colorectal adenocarcinoma.

Distribution of lymph nodes in the mesorectum: how deep is TME necessary?

BackgroundStandardization of total mesorectal excision (TME) had a great impact on decreasing local recurrence rates for the treatment of rectal cancer. However, exact numbers and distribution of lymph nodes (LN) along the mesorectum remains controversial with some studies suggesting that few LNs are present in the distal third of the mesorectum.MethodsEighteen fresh cadavers without a history of rectal cancer were studied. The rectum was removed by TME and then was divided into right lateral, posterior and left lateral sides, which were further subdivided into 3 levels (upper, middle and lower). A pathologist determined the number and sizes of the LNs in each of the nine areas, b linded to their anatomical origin.ResultsOverall, the mesorectum had a mean of 5.7 LNs (SD=3.7) and on average each LN had a maximum diameter of 3.0 mm (SD=2.7). There was no association between the mean number or size of LNs with gender, BMI, or age. There was a significantly higher prevalence of LNs in the posterior location (2.8 per mesorectum) than in the two lateral locations (0.8 and 1.2 per mesorectum; p=0.02). The distribution of LNs in the three levels of the rectum was not significant.ConclusionsThe distribution of LNs reinforces the fact that TME should always include the distal third of the mesorectum. Care must be taken to not violate the posterior aspect of the mesorectum.

Uso da terapia por pressão subatmosférica em feridas traumáticas agudas

OBJETIVO: avaliar a experiencia com o emprego de terapia por pressao subatmosferica no tratamento das lesoes traumaticas agudas das partes moles, em especial nos membros. METODOS: cento e setenta e oito pacientes com feridas traumaticas foram tratados pelo Centro de Feridas Complexas no periodo de janeiro de 2010 a dezembro de 2011 e, submetidos a terapia por pressao subatmosferica. RESULTADOS: dos 178 pacientes submetidos a terapia por pressao subatmosferica, 129 (72,5%) eram do sexo masculino e 49 (27,5%) apresentavam idade entre 18 e 40 anos. Os ferimentos descolantes nos membros foram o tipo de ferida traumatica mais comum, sendo responsaveis pela internacao de 83 (46,6%) pacientes. O tempo medio de internacao hospitalar foi 17,5 dias. Foram realizados 509 procedimentos cirurgicos (media de 2,9 por paciente). A terapia por pressao subatmosferica foi utilizada em 287 procedimentos, sendo 209 (72,8%) sobre feridas traumaticas e 78 (27,2%) sobre enxertos de pele. O numero de trocas de terapia por pressao negativa por paciente foi 1,6 e o tempo medio de utilizacao foi 8,5 dias por paciente. CONCLUSAO: os resultados foram considerados satisfatorios, diminuindo consideravelmente a morbidade e o tempo de cicatrizacao dessas lesoes em comparacao com tratamentos anteriormente executados como curativos. A terapia por pressao subatmosferica e um metodo util no tratamento de feridas agudas traumaticas, atuando como ponte entre o tratamento de urgencia e a cobertura cutânea definitiva destas lesoes, em comparacao com metodos mais tradicionais da cirurgia plastica.

Optimizing Outcomes in Free Flap Breast Reconstruction in the Community Hospital Setting: A Stepwise Approach to DIEP/SIEA Flap Procedures with Banking a Hemiabdominal Flap

Background Free flap breast reconstruction is a conventional procedure in many countries; however, microvascular compromise remains a devastating outcome. Given the morbidity of total necrosis, optimizing free flap salvage stands out as an important area for research, especially among surgeons to overcome the learning curve period and in resource constrained scenario such as community hospitals. To ensure free deep inferior epigastric perforator (DIEP)/superficial inferior epigastric artery (SIEA) flap breast reconstruction, the authors present a technique involving raising a hemiabdominal flap as a free flap, and banking the remaining flap to be utilized if needed in a subsequent procedure. Methods A retrospective review was performed on all free flap breast reconstructions. In this period, 84 patients (mean age: 50.1 ± 8 years) were included. Results In this study, 65.5% patients underwent immediate reconstruction, and 51.2% received DIEP reconstruction; 9.52% patients were returned to the operating room, and salvage reconstruction using the banked flap was performed in all patients. No differences were observed regarding early complications and age, body mass index, American Society of Anesthesiologists status, diabetes, smoking history, chemotherapy, radiotherapy, and type of flap used (p > 0.05). Hypertension was significantly associated with early complications (p < 0.05). Donor‐site complications were associated with RT (p < 0.05). Conclusion The banked flap is a reliable method for ensuring DIEP/SIEA flap survival and should be considered in higher risk reconstructions and community hospitals. We believe that the present technique can be a good addition to the arsenal of plastic surgeons dealing with free flap breast reconstructions in selected patients.