Recurrence rate and survival implications of surgical margins in patients with acral melanoma. Is a wide margin necessary?

INTRODUCTION: Appropriate size of resection margins in acral melanoma is not clearly established. OBJECTIVE: To investigate whether narrow-margin excision is appropriate for thick acral melanoma. METHODS: Three-hundred and six patients with acral melanoma were examined. Factors associated with recurrence and survival were analyzed according to surgical margin size (1 to 2 cm and > 2 cm). RESULTS: Out of 306 patients, 183 were women (59.8%). Median Breslow thickness was 6 mm; 224 cases (73.2%) were ulcerated, 154 patients (50.3%) had clinical stage III disease, while 137 were at stage II (44.8%) and 15 at stage IV (4.9%). All cases had negative margins, with a median of 31.5 mm. A Breslow thickness of 7 mm (p = 0.001) and clinical stage III (p = 0.031) were associated with recurrence; the factors associated with survival were Breslow index (p = 0.047), ulceration (p = 0.003), advanced clinical stage (p < 0.001), and use of adjuvant therapy (p = 0.003). CONCLUSION: A resection margin of 1 to 2 cm did not affect tumor recurrence or survival in patients with acral melanoma.

INTRODUCCIÓN: La extensión apropiada de los márgenes de resección en el melanoma acral no está claramente establecida. OBJETIVO: Investigar si la escisión con margen estrecho es adecuada en el melanoma acral grueso. MÉTODOS: Se estudiaron 306 pacientes con melanoma acral. Conforme a la extensión del margen quirúrgico (de 1 a 2 cm y > 2 cm), se analizaron los factores asociados a la recurrencia y la supervivencia. RESULTADOS: De 306 pacientes, 183 fueron mujeres (59.8 %). La mediana del grosor de Breslow fue 6 mm; 224 casos (73.2 %) fueron de tipo ulcerados, 154 pacientes (50.3 %) tenían enfermedad en estadio clínico III, 137 en II (44.8 %) y 15 en IV (4.9 %). Todos los casos presentaron margen negativo, con una mediana de 31.5 mm. Un grosor de Breslow de 7 mm (p = 0.001) y la etapa clínica III (p = 0.031) se asociaron a recurrencia; los factores asociados a la supervivencia fueron el índice de Breslow (p = 0.047), la ulceración (p = 0.003), la etapa clínica avanzada (p < 0.001) y el uso de adyuvancia (p = 0.003). CONCLUSIÓN: Un margen de resección de 1 a 2 cm no afectó la recurrencia tumoral ni la supervivencia en los pacientes con melanoma acral.

Prognosis of polypoid melanoma: a comparative study with non-polypoid melanomas.

Polypoid melanoma is considered an exophytic and frequently non-pigmented variant of nodular melanoma with an adverse prognosis; however, very few studies have been published about it with contradictory results. Therefore, our objective was to determine the prognostic value of this configuration in melanomas. A transversal retrospective study of 724 cases was analyzed according to the main configuration (polypoid vs. non-polypoid) regarding their clinicopathologic characteristics and survival analysis. Of the 724 cases, 35 (4.8%) met the definition of polypoid melanoma; such cases, compared with non-polypoid melanomas, were associated with a high Breslow thickness (7 mm vs. 3 mm), 68.6% had a Breslow >4 mm; showed different clinical stages of presentation, and presented more ulceration (77.1 vs. 51.4%). In the 5-year overall survival (OS) analysis, polypoid melanoma is associated with a lower 5-year OS, together with lymph node metastasis, Breslow thickness, clinical stage, mitoses per mm 2 , vertical growth phase, ulceration, and state of the surgical margins; however, in the multivariate analysis, the factors that remained independent predictors of death were the Breslow thickness groups, the clinical stage, the presence of ulceration, and the state of the surgical margins. Polypoid melanoma was not an independent predictor of OS. We found a prevalence of 4.8% of polypoid melanomas, which showed a worse prognosis than non-polypoid melanomas, explained by a higher proportion of ulcerated cases, greater Breslow thickness, and ulceration. However, polypoid melanoma was not an independent predictor of death.

Tasa de recurrencia e implicación del margen quirúrgico en la supervivencia del paciente con melanoma acral. ¿Es necesario un margen amplio? / Recurrence rate and survival implications of surgical margins in patients with acral melanoma. Is a wide margin necessary?

Resumen Introducción: La extensión apropiada de los márgenes de resección en el melanoma acral no está claramente establecida. Objetivo: Investigar si la escisión con margen estrecho es adecuada en el melanoma acral grueso. Métodos: Se estudiaron 306 pacientes con melanoma acral. Conforme a la extensión del margen quirúrgico (de 1 a 2 cm y > 2 cm), se analizaron los factores asociados a la recurrencia y la supervivencia. Resultados: De 306 pacientes, 183 fueron mujeres (59.8 %). La mediana del grosor de Breslow fue 6 mm; 224 casos (73.2 %) fueron de tipo ulcerados, 154 pacientes (50.3 %) tenían enfermedad en estadio clínico III, 137 en II (44.8 %) y 15 en IV (4.9 %). Todos los casos presentaron margen negativo, con una mediana de 31.5 mm. Un grosor de Breslow de 7 mm (p = 0.001) y la etapa clínica III (p = 0.031) se asociaron a recurrencia; los factores asociados a la supervivencia fueron el índice de Breslow (p = 0.047), la ulceración (p = 0.003), la etapa clínica avanzada (p < 0.001) y el uso de adyuvancia (p = 0.003). Conclusión: Un margen de resección de 1 a 2 cm no afectó la recurrencia tumoral ni la supervivencia en los pacientes con melanoma acral.

Abstract Introduction: Appropriate size of resection margins in acral melanoma is not clearly established. Objective: To investigate whether narrow-margin excision is appropriate for thick acral melanoma. Methods: Three-hundred and six patients with acral melanoma were examined. Factors associated with recurrence and survival were analyzed according to surgical margin size (1 to 2 cm and > 2 cm). Results: Out of 306 patients, 183 were women (59.8%). Median Breslow thickness was 6 mm; 224 cases (73.2%) were ulcerated, 154 patients (50.3%) had clinical stage III disease, while 137 were at stage II (44.8%) and 15 at stage IV (4.9%). All cases had negative margins, with a median of 31.5 mm. A Breslow thickness of 7 mm (p = 0.001) and clinical stage III (p = 0.031) were associated with recurrence; the factors associated with survival were Breslow index (p = 0.047), ulceration (p = 0.003), advanced clinical stage (p < 0.001), and use of adjuvant therapy (p = 0.003). Conclusion: A resection margin of 1 to 2 cm did not affect tumor recurrence or survival in patients with acral melanoma.

Prognosis of Mesorectal Tumor Deposits in Patients with Rectal Cancer Treated with Neoadjuvant Chemoradiotherapy and Total Mesorectal Excision.

BACKGROUND: Tumor deposits (TDs) are associated with adverse prognostic factors and decreased survival in colon cancer. However, there is no information of their survival impact in rectal cancer with neoadjuvant chemoradiotherapy (n-CRT). METHODS: Retrospective study in 223 patients with rectal cancer with n-CRT. A survival analysis of factors associated with decreased overall survival (OS) including TDs was performed. RESULTS: From 223 patients, 131 (58.7%) were men, mean age 59.8 (± 13.06) years, and 42 (18.8%) of them revealed TDs. Survival analysis of TDs showed no association with mortality. Factors associated with decreased 5-year OS were the histologic grade (p = 0.42), perineural invasion (p = 0.001), and mesorectal quality (p = 0.067). Perineural invasion (HR = 2.335, 95% CI = 1.198-4.552) remained as independent factor in the multivariate analysis. CONCLUSIONS: TDs were not associated with mortality in rectal cancer patients treated with n-CRT. Factors associated with decreased survival were inadequate mesorectal quality and perineural invasion.

Prognostic significance of tumor budding in melanoma.

Cutaneous melanoma is an aggressive neoplasm with growing incidence and continuous research is undertaken for novel prognostic factors. This current research aims to determine if tumor budding is an independent factor that correlates with the survival of patients with melanoma. A total of 742 cases of melanoma were evaluated. A receiver operating curve (ROC) was performed to analyze tumor budding impact on survival, identifying a cutoff point associated with death. Subsequently, two groups of participants were created based on that result. Participants within the two groups were compared for clinicopathologic characteristics and survival analysis. Also, a multivariate analysis was performed. Of the total, 447 (60.2%) melanomas occurred in women and 295 in men. The mean age was 57.5 years + 15.75. The most common location was in acral areas (68.2%) followed by trunk (16.7%) and head and neck (15.1%). At presentation, 142 cases (19.1%) presented as stage I, 307 (41.4%) as stage II, 269 (36.3%) as stage III, and 24 (3, 2%) in stage IV. Regarding tumor budding, 586 (79%) cases showed tumor budding (at least one bud in 0.785 mm 2 ), with a median of 5. From the ROC curve, 4.5 tumor buds/0.785 mm 2 was the best cutoff point for correlation with death, grouping the series in low budding (0-4 buds/0.785 mm 2 ) and high budding ( > 5 buds/0.785 mm 2 ). Cases with high tumor budding were associated with older age, acral location, advanced clinical stages, ulceration, recurrence, and death. High tumor budding was associated with a significant decrease in 5-year overall survival (94.4% vs. 55.5%, P < 0.001). In the multivariate analysis, the factors remaining as independent predictors of survival were acral location, clinical stage IV, recurrence during clinical follow-up, and high tumor budding. High tumor budding (>5 buds in 0.785 mm 2 ) independently correlates with 5-year overall survival rates and is associated with older age, acral location, advanced clinical stages, ulceration, recurrence, and death.

Lymph node retrieval in radical gastrectomy: the pathologist alone or the surgeon-pathologist team?

INTRODUCTION: Lymph node (LN) dissection is an important prognostic factor in gastric cancer. There is little information comparing the LN count depending on whether they are dissected in the operating room or in the pathology laboratory. AIM: To establish if the LN count is greater in either of them. MATERIAL AND METHODS: From 2015 to 2017 all consecutive gastrectomies with D2 dissection were prospectively evaluated based in either of 2 protocols: One started in the operating room where the surgeon separated the LN levels and then submitted the entire adipose tissue with LNs (undissected) to pathology in separate containers; the pathologist dissected the LNs from the specimens. The second protocol consisted of sending the tissue/LNs to pathology as usual (adipose tissue and LN attached to the stomach). RESULTS: A total of 83 patients were analysed. The mean age was 58.4 years. The median number of LNs dissected in the protocol starting in the operating room was 56 (IQR: 37-74), whereas the pathology laboratory dissected a median of 39 LNs (IQR 26-53) (p = 0.005). The survival of cases dissected by both protocols were comparable (median survival of 48 and 43 months, p = 0.316). CONCLUSIONS: The LN final count is significantly higher when LN levels are separated beforehand in the operating room compared to dissection only in pathology; however, this does not impact survival, perhaps because the number of dissected nodes in both groups is high and the quality of the surgery is good.

Prognostic variables in patients with thick melanomas. Analysis of 362 cases.

BACKGROUND: Melanoma epidemiological and prognostic studies are based on Caucasian populations, in whom the predominant subtype is superficially-spreading melanoma and in whom thin melanomas (Breslow < 3 mm) predominate. Mexican patients show a predominance of thick melanomas (Breslow ≥ 3 mm), and the acral subtype is the most common. There are no publications on prognostic factors in thick melanomas. We hypothesize that we will identify factors that determine the prognosis in this group of patients. OBJECTIVE: To identify clinical-pathological factors associated with the prognosis of patients with thick melanomas in the Mexican population. MATERIAL AND METHODS: Data on melanomas with Breslow > 3 mm were collected from 2010 to 2015. The prognostic influence of various clinical-pathological factors was analyzed. RESULTS: The most common subtypes were acral melanoma in 271 patients (74.9 %) and nodular melanoma in 49 (13.5 %). Median Breslow thickness was 7 mm. 56.6 % of the patients had lymph node metastases (clinical stage [CS] III), 269 (74.3 %) had ulceration, and surgical margins were positive in 15 (4.1 %). Elevated neutrophil: lymphocyte ratio (≥ 2) was found in 188 (51.9 %). The variables associated with lower overall survival were CS (p < 0.001), Breslow thickness (p = 0.044), ulceration (p = 0.004), mitotic activity (p < 0.001), < 2-cm margin (p < 0.001) and an increased neutrophil: lymphocyte ratio (p = 0.037). In the multivariate analysis, the factors associated with overall survival were CS, mitotic activity, and surgical margin. CONCLUSIONS: In patients with thick melanomas, overall survival is influenced by mitotic activity, a positive margin, and clinical stage.

ANTECEDENTES: Los estudios sobre factores pronóstico de melanoma están basados en poblaciones cau­cásicas, con predominio de melanomas delgados (Breslow < 3 mm). Los pacientes mexicanos muestran predominio de melanomas gruesos (Breslow ≥ 3 mm). OBJETIVO: Identificar factores asocia­dos al pronóstico de pacientes con melanomas gruesos. MATERIAL Y MÉTODOS: Se analizó la influencia pronóstica de factores clinico­patológicos en 362 melanomas gruesos. RESULTADOS: La mediana de Breslow fue de 7 mm, 271 (74.9 %) pacientes tuvieron melanoma acral y 49 (13.5 %) melanoma nodular. El 56.6 % de los pacientes se encontró en etapa clínica [EC] III), 269 (74.3 %) tenía ulceración y 15 (4.1 %) márgenes positivos. Las variables asociadas con menor supervivencia global [SG] fueron la EC (p < 0.001), Breslow (p = 0.044), ulceración (p = 0.004), mitosis (p < 0.001) y margen < 2 cm (p < 0.001) . En el análisis multivariante los factores que influyen en SG fueron la EC, mitosis y el margen quirúrgico. CONCLUSIONES: En pacientes con melanomas gruesos la SG es influida por un margen positive, mitosis y EC.

The influence of body mass index on the survival of patients with melanoma. A cross-sectional study of 707 patients.

INTRODUCTION: Obesity has been linked with an increased incidence of melanoma; however, there are few data about its impact on melanoma prognosis. We aimed to determine if there is an association between body mass index (BMI) and overall survival (OS) in 707 patients with melanoma. MATERIAL AND METHODS: A retrospective study of 707 patients with melanoma collected consecutively from 2005 to 2015 with a diagnosis of melanoma, who were been diagnosed and treated in our institution and who had clinical follow-up was carried out. Survival analysis was performed comparing patients according to their BMI. RESULTS: In a multivariate analysis, factors influencing the 5-year OS were a positive margin (HR = 3.475, 95% CI: 1.829-6.600), the clinical-stage (HR = 2.565, 95% CI: 2.020-3.257, per switch to the upper stage), ulceration (HR = 3.475, 95% CI: 1.829-6.600), and BMI (HR .905, p = 0.018 for the overweight group; HR = 0.663, p = 0.021 for obesity grade I). CONCLUSIONS: Patients who had a BMI between 25 and 34.9 kg/m2 had better survival.

Prognostic impact of microsatellite instability in gastric cancer.

Gastric cancer is a common and deadly cancer. Several factors are associated with its prognosis; however, controversy exists about the role of microsatellite instability (MSI). We aimed to determine the 5-year overall survival (OS) of MSI in gastric adenocarcinoma. A cross-sectional study was carried out on gastric adenocarcinoma in clinical stages I to III treated with D2 gastrectomy between 2010-2013. MSI was demonstrated by immunohistochemistry. We performed a survival analysis comparing cases with and without MSI. From 102 cases, 9.8% showed MSI. The median age was 63 years (range 33-91 years), and 57.8% were men. The more prevalent site of occurrence was the antrum (46.1%), 78.5% of the cases presented in stage III, 47.1% were of the diffuse type, 45.1% were of an intestinal type, and 7.8% were mixed. MSI cases were associated with lower clinical stages (stages I-II) and with better 5-year OS (100 vs. 47 months, p = 0.017). In a multivariate analysis, MSI was independently associated with better survival (HR = 0.209, 95% CI: 0.046-0.945, p = 0.042). MSI gastric cancers presented in early clinical stages and had favourable prognosis compared with non-MSI cancers.

Variables pronósticas de pacientes con melanomas gruesos. Análisis de 362 casos / Prognostic variables in patients with thick melanomas. Analysis of 362 cases

Resumen Antecedentes: Los estudios sobre factores pronóstico de melanoma están basados en poblaciones caucásicas, con predominio de melanomas delgados (Breslow < 3 mm). Los pacientes mexicanos muestran predominio de melanomas gruesos (Breslow ≥ 3 mm). Objetivo: Identificar factores asociados al pronóstico de pacientes con melanomas gruesos. Material y métodos: Se analizó la influencia pronóstica de factores clinicopatológicos en 362 melanomas gruesos. Resultados: La mediana de Breslow fue de 7 mm, 271 (74.9 %) pacientes tuvieron melanoma acral y 49 (13.5 %) melanoma nodular. El 56.6 % de los pacientes se encontró en etapa clínica [EC] III), 269 (74.3 %) tenía ulceración y 15 (4.1 %) márgenes positivos. Las variables asociadas con menor supervivencia global [SG] fueron la EC (p < 0.001), Breslow (p = 0.044), ulceración (p = 0.004), mitosis (p < 0.001) y margen < 2 cm (p < 0.001) . En el análisis multivariante los factores que influyen en SG fueron la EC, mitosis y el margen quirúrgico. Conclusiones: En pacientes con melanomas gruesos la SG es influida por un margen positive, mitosis y EC.

Abstract Background: Studies on prognostic factors in melanoma are based on Caucasian populations, with a predominance of thin melanomas (Breslow <3 mm). Mexican patients show a predominance of thick melanomas (Breslow ≥ 3 mm). Objective: To identify factors associated with the prognosis of patients with thick melanomas. Material and methods: The prognostic influence of clinicopathological factors was analyzed in 362 thick melanomas. Results: The Breslow median was 7 mm, 271 (74.9 %) patients had acral melanoma and 49 (13.5 %) nodular melanoma. The 56.6 % of patients were found in clinical stage [CS] III), 269 (74.3 %) had ulceration, and 15 (4.1 %) had positive margins. The variables associated with lower overall survival [OS] were CS (p < 0.001), Breslow (p = 0.044), ulceration (p = 0.004), mitosis (p < 0.001) and margin < 2 cm (p < 0.001). In the multivariate analysis, the factors influencing OS were CD, mitosis, and the surgical margin. Conclusions: In patients with thick melanomas, OS is influenced by a positive margin, mitosis and CS.

The usefulness of intraoperative consultation for the diagnosis of borderline ovarian tumors.

BACKGROUND: Borderline ovarian tumors (BTs) must be recognized during the surgery by intraoperative consultation (IOC) to guide surgical treatment; however, this diagnosis can be imprecise. Therefore, this study aimed to evaluate the diagnostic accuracy of IOC for the diagnosis of BT. METHODS: A retrospective cohort study was carried out including all women diagnosed with a pelvic tumor consecutively surgically treated from 2005 to 2015 with IOC. We calculated the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and likelihood ratios (LR) for the IOC and BTs. RESULTS: A total of 758 patients were enrolled, the median age was 44 years, the median tumor size was 11.8 cm, and the median CA-125 levels were 45.65 U/µL. After IOC, 458 (64.1%) cases were diagnosed as benign, 111 (14.7%) as BT, and 161 (21.2%) as malignant. The definitive diagnosis was a benign tumor in 448 (59.1%) cases, BT in 110 (14.5%), and 200 (26.4%) cases were malignant. The diagnostic accuracy of the IOC for BT diagnosis was 89.8% (sensitivity =65.5%, specificity =93.9%). The diagnosis performance of IOC for the diagnosis between BT and benign tumors (n=546) had a sensitivity of 69.9%, a specificity of 98.4%, and a diagnostic accuracy of 84%; meanwhile for the diagnosis between BT and malignant tumors (n=242) IOC had a sensitivity of 92.3%, a specificity of 81.7%, and a diagnostic accuracy of 87%. CONCLUSIONS: For practitioners, knowing the accuracy and limitations of the IOC for BT enables the better selection of cases to perform a complete staging surgery.

BRAF V600E Expression by Immunohistochemistry in Colon Cancer and Clinico-pathologic Features Associated with BRAF-Mutated Colonic Cancers in Mexican Patients.

BACKGROUND: BRAF evaluation is currently limited to molecular techniques, which are expensive and not widely available to practicing pathologists. Our objective was to determine the diagnostic performance of immunohistochemistry (IHC) against BRAF V600E for BRAF mutation and the secondary objective was determining histopathological characteristics of colon carcinomas with BRAF mutated. METHODS: Cases of adenocarcinoma of the colon with a known BRAF mutation status were identified from the pathological files of our institution. RESULTS: We analyzed 135 cases, 13 cases had the BRAF mutation (9.6%) and 122 were non-mutated. The mutated cases expressed intense and diffusely the anti-antibody against BRAF V600E, and 119 (97.5%) of the 122 cases without mutation were negative and the remaining 3 were focal and weakly positive. The IHC demonstrated a sensitivity of 100%, specificity of 97.5%, positive predictive value of 81.3% (95% CI = 56.9 to 93.4%), negative predictive value of 100% (95% CI = 89 to 100%), and an overall accuracy of 97.8%. The only significant clinicopathological differences between cancers with BRAF mutated compared with BRAF non-mutated were that mutated had less lymph node metastases (23% vs. 68.1%) and the tumor size was greater (median 90 mm vs. 60 mm). The survival between groups was not statistically significant. CONCLUSION: IHC against BRAF V600E showed an excellent performance, making it feasible as an alternative for molecular examination. Tumors with BRAF mutated did not show distinctive clinico-pathological characteristics, except for a larger tumor size.

Report of three cases of gastric choriocarcinomas-an emphasis on morphologic changes in the non-affected gastric mucosa.

Primary gastric choriocarcinomas (PGC) are very rare and aggressive neoplasms with a worrisome prognosis. Most cases are reported in Asia and presented in middle-aged adults with male predominance. Most cases are associated with an intestinal adenocarcinoma; however, the pathogenesis of this tumor is uncertain. No previous reports exist of the characteristics of the non-tumoral stomach in these patients, and this data that could help to clarify their pathogenesis. We presented a series of three cases of PGC in Latin American patients, emphasizing the characteristics of non-neoplastic mucosa.

Acral Lentiginous Melanoma: Survival Analysis of 715 Cases.

INTRODUCTION:: Acral lentiginous melanoma (ALM) is an aggressive variant of melanoma; the incidence, prevalence, and prognosis differ among populations. We analyzed clinicopathological features and survival in Hispanics, a population with high ALM prevalence. MATERIAL AND METHODS:: From 1144 patients with melanoma, we analyzed 715 ALMs and 429 non-ALMs from the National Referral Cancer Centre and compared survival. RESULTS:: Of the ALM group, 62.8% were female; the median age was 58 years. The mean Breslow thickness was 3.56 ± 7.16 mm. ALM patients showed an estimated 5-year disease-specific survival (DSS) of 53.3%, 52.7%, and 40.8% for stage I, II, and III, respectively. For non-ALM patients, the DSS rates were 66%, 60.8%, and 48.4% for stage I, II, and III disease, respectively. Overall, the 1-, 3-, and 5-year DSS rates for patients with ALM were 85.1%, 59.4%, and 46.3%, respectively; for non-ALM patients, they were 81.3%, 64.8%, and 55.7%, respectively ( P = .168). In the multivariate analysis, factors associated with decreased DSS were high Breslow thickness, recurrence, ulceration, male sex, and advanced stage. CONCLUSIONS:: The 1-, 3-, and 5-year DSS rates of patients with ALM were not statistically different from those of non-ALM patients. In addition to known adverse prognostic factors, male sex was also associated with worse survival.

Gastrointestinal Stromal Tumors Risk of Recurrence Stratification by Tumor Volume is a Best Predictor Compared with Risk Based on Mitosis and Tumor Size.

PURPOSE: Gastrointestinal stromal tumors (GIST) have the potential to recur and metastasize. Several prognostic schemes have been developed, mostly based on the mitotic count, diameter, and tumor site. However, these systems are not precise enough. The research question was whether the tumor size determined by volumetry allows a better risk stratification than the traditional system, and our aim was to determine the value of tumor volumetry, a feasible and simple parameter, in the recurrence of GIST. METHODS: Seventy-four cases of GIST were studied. The cases presented with non-metastatic disease, which were resected and did not receive imatinib. We compared the clinico-pathologic features of the cases with recurrence against those with non-recurrence and compared the tumor volumetry against the classification system based on tumor size and mitosis. RESULTS: The median age was 58 years (range: 25 to 91 years). Half of the cases were presented in the stomach. The tumor size had a median of 8 cm (range of 1-30 cm). The median mitosis count for 50 HPF was 4 (range 0-92). During the period of study, 16 (21.6%) patients suffered recurrence. The significant differences were that patients with recurrence accounted for more deaths and the follow-up period was larger. The area under the curve (AUC) of the volumetry classification was superior to the AUC of the classification system based on tumor size and mitosis (NIH-criteria) (p = .05). CONCLUSION: Tumor volumetry calculated in the surgical specimen and/or pre-operative tomography was superior to the NIH consensus in stratifying the risk of recurrence in GIST.

Overall survival of patients with colon cancer and a prolonged time to surgery.

BACKGROUND: Factors associated with the time to surgery (TTS) and survival in colon cancer (CC) have not been well studied. Our aim was to find if the TTS has changed in our institution over time and to determine if it influences the survival. METHODS: Retrospective cross-section study of 266 CC analyzed between two periods, and according to the quartiles of TTS, we performed a survival analysis. RESULTS: The median age was 57 years; there was no predominance of sex, and about half of the patients were in stage III. The median TTS was 38 days, and 75% of the cases were operated before 60 days. The median TTS for 2005 to 2010 was 36 days, while for 2011 to 2015 was 41 days (P = 0.107). The survival was not statistically different between cases (1) operated with a delayed TTS or not, (2) operated in four cut-off points of TTS, (3) two different periods of attention, and (4) according to the clinical stage. CONCLUSION: We did not find an association between the TTS with low survival. TTS has increased in the last period so we must work to make the diagnostic process more efficient in our patients to meet international quality standards.

Overweight but not obesity is associated with decreased survival in rectal cancer.

AIM OF THE STUDY: To analyse the influence of overweight and obesity in disease-specific survival (DSS) in rectal cancers at stages I-III in a population with high prevalence of overweight/obesity. MATERIAL AND METHODS: The population (N = 304) consisted of Mexican patients with stage I-III rectal cancer during the period between 2009 and 2015. Patients were divided based on their body mass index (BMI) into normal weight 18-25 kg/m2, overweight 25-29 kg/m2, and obesity BMI > 30 kg/m2 groups. Comparison of clinicopathologic features and survival analysis were performed. RESULTS: The median age was 58 years (interquartile range [IQR] 50-65) and the mean BMI was 26.03 ±4.06 kg/m2. Patients in the obesity and overweight groups received a lower proportion of preoperative treatment and had a higher proportion of patients in stage II. Overweight patients had a lower baseline neutrophil/lymphocyte ratio and lower survival rate than patients with normal weight and with obesity (mean survival of 69.5 months vs. 81.15 months and 86.4 months, respectively). The estimated five-year DSS was 51% for the overweight group, 81% for the normal group, and 82% for the obesity group (p = 0.026). CONCLUSIONS: Patients with stage I-III rectal cancer in the overweight group showed a lower DSS compared to groups with normal weight and with obesity, with the last two being similar.

Frequency of Defective Mismatch Repair System in a Series of Consecutive Cases of Colorectal Cancer in a National Cancer Center.

BACKGROUND: The frequency of colorectal cancer (CRC) with defective mismatch repair (dMMR) is estimated between 5 and 15%. In our population, the frequency of dMMR is unknown. Our objective was to show the frequency of dMMR. METHODS: Determination of dMMR with immunohistochemistry was performed prospectively for 202 patients who presented consecutively with CRC for the first time at our institution. RESULTS: The median age was 59 years (IQR 47 to 68), 119 (58.9%) were women, and 43 (21.3%) cases showed dMMR. The only clinicopathological characteristics associated with dMMR were the location in the right colon and the presence of a family history of cancer. In the multivariate analysis, only the presence of the tumor in the right colon was associated with dMMR (OR = 5.823, 95%-C.I. = 2.653-12.784, p < .001). CONCLUSION: The 21.3% of the cases demonstrated a dMMR and the only clinical-pathological characteristic associated with dMMR was location in the right colon.

Comparison of 3 Ways of Dissecting the Pancreatoduodenectomy Specimen and Their Impact in the Lymph Node Count and the Lymph Node Metastatic Ratio.

BACKGROUND: Lymph node metastasis (LNM) is a strong prognostic factor in the cancer of the pancreatobiliary tree, but it is influenced by the number of lymph nodes (LNs). The lymph node ratio (LNR) is considered a more reliable factor than the number of LNM. The aim was to examine the LN retrieval and the LNR of 3 pathologic work-up strategies. METHODS: Pancreaticoduodenectomies (n = 165) were analyzed comparing 3 pathological dissection techniques, classified as "control," "Verbeke method," and "Adsay method" groups. RESULTS: The mean of the dissected LNs and the number of cases with >20 LNs were superior in the Adsay method group, compared with the other groups ( P < .001). The LNR was different between the Adsay and Verbeke groups (0.144 vs 0.069, P = .032). The median of the 3 positive LNs was associated with decreased survival compared with an absence of LNM (3-year specific survival of 48% vs 22%, P = .011). In the multivariate analysis, LNM (hazard ratio = 6.148, 95% confidence interval = 2.02-8.1, P = .042) and the evaluation of >15 LNs (hazard ratio = 12.52, 95% confidence interval = 5.51-21.01, P = .001) were independent predictors of survival. CONCLUSION: The Adsay technique for LN retrieval was associated with a better LN count, more cases with LNM, and an LNR >0.1.