Immune Dysfunction as Measured by the Systemic Immune-Inflammation Index is Associated with the Sub-Type of Minimal Residual Disease and Outcome in Stage II Colon Cancer Treated with Surgery alone.

OBJECTIVE: Within 5 years after curative surgery for stage II colon cancer 25% of patients will relapse due to minimal residual disease (MRD). MRD is the net result of the biological properties of subpopulations of primary tumour cells which enable them to disseminate, implant in distant tissues and survive and the immune system's ability to eliminate them. We hypothesize that markers of immune dysfunction such as the systemic inflammation index (SII) are associated with the sub-type of MRD defined by bone marrow micro-metastasis (mM) and circulating tumour cells (CTCs). A higher immune dysfunction being associated with a more aggressive MRD and worse prognosis. METHODS AND PATIENTS: Blood and bone marrow samples were taken to detect CTCs and mM using immunocytochemistry with anti-CEA one month after surgery. The SII, absolute neutrophil, platelet and lymphocyte counts (ANC, APC, ALC) were determined immediately pre-surgery and one month post-surgery. These were compared with the sub-types of MRD; Group I MRD (-); Group II mM positive and Group III CTC positive; cut-off values of SII of >700 and >900 were used. Follow-up was for up to 5 years or relapse and survival curves using Kaplan-Meier (KM) were calculated. RESULTS: One hundred and eighty one patients (99 women) participated, mean age 68 years, median follow up 4.04 years; I: = 105 patients, II: N= 36 patients, III: N=40 patients. The SII significantly decreased post-surgery only in Group I patients. The frequency of SII >700 and >900 was significantly higher in Group III, between Groups I and II there was no significant difference.  The SII was significantly associated with the number of CTCs detected. The 5-year KM was 98% Group I, 68% Group II and 7% Group III. CONCLUSIONS: The results of the study suggest that the severity of immune dysfunction as determined by the SII is associated with differing sub-types of MRD and a worse prognosis; increasing immune dysfunction is associated with a more aggressive CTC positive MRD sub-type; a more severe immune dysfunction is associated with a higher number of CTCs detected.
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[CAPRA score vs minimal residual disease as predictors of biochemical recurrence after radical prostatectomy.] / La puntuación CAPRA frente a los subtipos de enfermedad residual mínima para predecir la recidiva bioquímica después de la prostatectomía radical.

OBJECTIVE: To compare the classification CAPRA (based on clinical-pathological findings) and minimal residual disease (MRD) (based on biological characteristics) to predict biochemical failure (BF). METHOD AND PATIENTS: The clinical-pathological findings of the prostate biopsy were used to determine the CAPRA score, classifying patients into low, intermediate and high risk. Blood and bone marrow samples to detect circulating prostate cells (CPCs) and micro-metastasis were taken. The samples were classified as positive if ≥1 prostate cell was detected, forming three subgroups; Group A (MRD negative), Group B (micro-metastasis positive, CPC negative) and Group C (CPC positive). Patients were followed-up for 10 yearsor BF. Kaplan-Meier biochemical failure free survival (BFFS) curves, a predictive flexible parameter survival model and mean restricted survival times (MRST) were determined. RESULTS: 347 men participated, BF risk increased with increasing CAPRA score, HR 1.21 intermediate, 1.64 high risk; versus MRD HR 1.91 and 4.43 for Groups Band C. After 10 years the BFFS and MRST were 76%, 50% and 17% and 9, 7 and 5 years respectively for CAPRA versus 94%, 57% and 26% and 10, 9 and 6 years respectively for MRD. The concordance between observed and predicted BFFS was acceptable for CAPRA (Harrell´s C 0.64) and very good (0.92) for MRD. The BFFS curves for MRD were not proportional with time, they were similar for 5 years for Groups A and B, with increasing BFFS in Group B there after.The CAPRA score did not distinguish between Groups A and B, one third of low risk CAPRA patients had CPCs detected. CONCLUSIONS: The MRD classification was superior to CAPRA, differentiating between early and late failure.

OBJETIVO: Comparar la puntuación CAPRA (en función de los hallazgos clínico-patológicos) y la enfermedad residual mínima (ERM) (en función de las propiedades biológicas) para predecir la recidiva bioquímica (RB).MÉTODOS Y PACIENTES: Los hallazgos clínico-patológicos de biopsias de próstata determinaron la puntuación CAPRA definiendo pacientes de bajo, intermedio y alto riesgo de la RB. Se obtuvieron muestras de sangre y médula ósea para detectar CPCs (Células Prostáticas Circulantes) y micro-metástasis usando inmunocitoquímica. Se clasificaron como positivas si se detectaba ≥1 célula en la muestra. Se formaron tres subgrupos: Grupo A (ERM negativo), Grupo B (micro-metástasis positivo, CPC negativo) y Grupo C (CPC positivo). Los pacientes fueron seguidos durante diez años o hasta la RB. Las curvas de supervivencia libre de recidiva bioquímica (SLRB) se construyeron usando el método de Kaplan Meier, un modelo de parámetro flexible (supervivencia predecida) y el tiempo de supervivencia medio restringido (TSMR) para cada subgrupo. RESULTADOS: 347 hombres participaron; el riesgode RB aumentó proporcionalmente; HR 1,21 riesgo intermedio,1,64 riesgo alto para CAPRA versus 1,91 Grupo B y 4,43 Grupo C para EMR. Después de diez años, el SLRB y el TSMR fueron 76%, 50%, 17% y 9,7 y 5 años respectivamente para CAPRA versus 94%, 57%, 26% y 10, 9 y 6 años respectivamente para EMR. El acuerdo entre SLRB observada y prevista fue aceptable para CAPRA (Harrell´s C 0,64) y muy buena (0,92) para EMR. Las curvas SLRB para la EMR no fueron proporcionales; para Grupos A y B fueron similares hasta cinco años, luego hubo una falla creciente en el Grupo B. La puntuación de CAPRA no logró distinguir entre los Grupos A y B, un tercio del Grupo C de alto riesgo tenía una puntuación CAPRA de bajo riesgo. CONCLUSIONES: La clasificación ERM fue superior de la CAPRA, diferenciando entre la RB temprana y tardía.

The association of the neutrophil-lymphocyte ratio with the presence of minimal residual disease and outcome in patients with Stage II colon cancer treated with surgery alone.

AIM: Despite curative surgery, 25% of patients with Stage II colorectal cancer will relapse due to minimal residual disease (MRD). Markers of immune function, such as the neutrophil to lymphocyte ratio (NLR), may be associated with MRD defined by bone marrow micro-metastasis (mM) and circulating tumour cells (CTCs). METHOD: A prospective cohort study of consecutive patients with Stage II colon cancer patients attended at a single centre between 2007 and 2014. Blood and bone marrow samples were taken to detect CTCs and mM using immunocytochemistry with anti-carcinoembryonic antigen 1 month after surgery. The NLR and absolute neutrophil and lymphocyte counts were determined immediately pre-surgery and 1 month post-surgery. These were compared with the sub-types of MRD: group I MRD(-); group II mM positive and group III CTC positive. Cut-off values of the NLR of >3.0 and >5.0 were used. Follow-up was for up to 5 years or relapse and disease-free survival (DFS) was calculated using Kaplan-Meier analysis. RESULTS: In all, 181 patients (99 women) participated. Mean age was 68 years. Median follow-up was 4.04 years: I, N = 105; II, N = 36; III, N = 40. The NLR significantly decreased post-surgery only in group I patients. The frequency of NLR >3.0 and >5.0 was significantly higher in group III; between groups I and II there was no significant difference. 5-year DFS was 98% in group I, 68% in group II and 7% in group III. CONCLUSIONS: Patients with a significantly higher immune dysfunction had a shorter time to disease progression, a worse DFS and the presence of CTCs.

OBJETIVO: En los primeros 5 años tras cirugía curativa para cáncer de colon en estadio II, el 25% de los pacientes tendrá una recidiva tumoral a causa de la presencia de enfermedad mínima residual (EMR). La hipótesis del presente estudio es que los marcadores de la función inmune, como la ratio neutrófilos- linfocitos (RNL), están asociados con el subtipo de EMR, clasificado por la presencia de micro-metástasis de médula ósea (mM) o células tumorales circulantes (CTCs) y con los resultados oncológicos. MÉTODOS Y PACIENTES: Se trata de un estudio prospectivo, observacional, monocéntrico que incluye una serie consecutiva de pacientes con cáncer del colon en estadio II tratados con cirugía curativa entre 2007 y 2014. Se tomaron muestras de sangre y médula ósea para detectar CTCs y mM mediante inmuno-citoquímica con anticuerpos anti-CEA un mes después de la cirugía. El numero de neutrófilos y linfocitos y el RNL se determinaron antes y un mes después de la cirugía y sus valores se compararon entre los diferentes grupos de EMR: grupo I, sin evidencia de EMR; Grupo II con mM positivo; Grupo III con CTCs positivo. El seguimiento oncológico fue de hasta 5 años y se calcularon las curvas de sobrevivencia libre de enfermedad (SLE) utilizando las curvas de Kaplan-Meier. RESULTADOS: se incluyeron en el presente estudio 181 pacientes (99 mujeres), con una edad media de 68 años y una mediana de seguimiento de 4,04 años; de acuerdo con la presencia de EMR se clasificaron los pacientes en Grupo I (n=105), Grupo II (n=36) y Grupo III (n=40). El RNL disminuyó significativamente después de la cirugía solo en el Grupo I. El porcentaje de pacientes con RNL> 3,0 y > 5,0 fue significativamente mayor en el Grupo III, sin diferencias significativas entre los Grupos I y II. La SLE a 5 años fue del 98% en el Grupo I, 68% en el Grupo II y 7% en el Grupo III. CONCLUSIONES: Los pacientes con una peor disfunción inmunológica presentan una recidiva mas precoz, una peor SLE y la presencia de células tumorales circulantes.

Subtypes of minimal residual disease and outcome for stage II colon cancer treated by surgery alone.

INTRODUCTION: Twenty-five percent of stage II colon cancer (CC) patients relapse within 5 years due to minimal residual disease (MRD) not eliminated by surgery. We hypothesise that subtypes of MRD, defined by circulating tumour cells (CTCs) and bone marrow micrometastasis (mM), have different types and kinetics of relapse. METHODS AND PATIENTS: One month after surgery, blood and bone marrow samples were taken to detect CTCs and mM using immunocytochemistry with anti-carcinoembryonic antigen (CEA). Follow-up was for up to 5 years or relapse. Disease-free survival curves using Kaplan-Meier (DFS) and restricted mean disease-free survival times (RMST) were calculated for three prognostic groups: A: MRD (-), B: mM (+) CTC (-) MRD and C: CTC (+) MRD. RESULTS: One hundred and eighty-one patients (82 men) have participated, mean age was 68 years and median follow-up was 4.04 years (A (N = 105), B (N = 36) and C (N = 40)). For the whole cohort of 5 years, DFS was 70%, median DFS has not reached (Groups A: 98%, B: 63% and C: 7%) and median DFS for Groups A and B have not reached. RMST for the whole cohort of 4.1 years, Group A was 4.9 years, B was 4.1 years and C was 1.7 years. Serum CEA was significantly higher in Group C. No significant differences for sex, age or high-risk adverse prognostic factors between groups were detected. CONCLUSIONS: MRD subtypes define relapse patterns and may be useful to define the risk of relapse in stage II CC patients, in which patients may benefit or not from additional therapy and warrants further studies with a larger number of patients.

The CAPRA-S score versus subtypes of minimal residual disease to predict biochemical failure after radical prostatectomy.

OBJECTIVE: The objective of this study was to compare the CAPRA-S score (based on clinicopathological findings) and the subtypes of minimal residual disease (MRD) (based on the biological properties of cancer cells) to predict biochemical failure (BF) after prostatectomy radical. PATIENTS AND METHODS: This was a prospective single-centre study of men who underwent radical prostatectomy. One month after surgery, the blood and bone marrow were taken for circulating prostate cell (CPC) and micrometastasis detection, identified using anti-PSA immunocytochemistry and defined as positive or negative. Patients were classified as Group A: CPC and micrometastasis negative, Group B: micrometastasis positive and CPC negative and Group C: CPC positive. CAPRA-S scores were classified as low, intermediate and high risk. Kaplan-Meier curves for biochemical failure-free survival (BFFS) and restricted mean survival time (RMST) to biochemical failure were determined and compared for up to 10 years. RESULTS: 347 men participated with a median follow-up of 7 years, BFFS decreased proportionally with increasing CAPRA-S score and HR 1.13 and 1.65 for intermediate and high risk, respectively. After 10 years, the BFFS and RMST were 68%, 47% and 16% and 9, 7 and 6 years, respectively. The BFFS curves for MRD were not proportional; Group A and B BFFSs were similar up to 5 years, and then, there was an increasing failure in Group B patients After 10 years, the BFFS and RMST were 95%, 57% and 27% and 10, 9 and 6 years respectively. The CAPRA-S score failed to distinguish between Groups A and B, and one-third of high-risk Group C had low-risk CAPRA-S scores. MRD hazard ratios were Group B 1.76 and Group C 4.03. CONCLUSIONS: The MRD prognostic classification was superior to the CAPRA-S score in predicting BFFS and differentiated between early and late BF. The results need to be confirmed in larger studies.

The Epstein criteria predict for organ-confined prostate cancer but not for minimal residual disease and outcome after radical prostatectomy.

OBJECTIVE: The Epstein criteria (EC) used to select men for active surveillance do not predict biologically insignificant diseases. Minimal residual disease (MRD) is an undetected microscopic disease that remains after radical prostectomy (RP) and is a biological classification associated with the risk of treatment failure. Subtypes of MRD, the 10-year biochemical failure free survival (BFFS), and restricted mean biochemical failure free survival time (RMST) were determined and compared in EC patients treated with RP. MATERIAL AND METHODS: Consecutive patients with a Gleason 6 biopsy treated at a single institution were divided into those who did or did not fulfill the EC and underwent RP. One month after surgery, samples were taken for the detection of circulating prostate cells (CPCs) and bone marrow micrometastasis. MRD was defined as negative for both CPCs and micrometastasis; patients were positive for micrometastasis and CPCs separately. BFFS for up to 10 years and RMST were determined for each MRD subgroup for EC positive and negative patients. RESULTS: EC positive men (137/426) were significantly older (p<0.05) and had negative MRD, pT2 (pathologically organ confined) disease (<0.02), and lower frequency of upgrading (p<0.02). Of the EC positive men, 71% were MRD negative, 13% were positive for micrometastasis, and 16% were positive for CPCs with respective 10-year BFFS of 99%, 89%, and 21% (<0.001) (hazard ratio: 1.00, 1.76, 4.03, respectively) with no signficant differences between the 10-year BFFS or RMST for MRD subgroups for EC positive and negative patients. CONCLUSIONS: EC predict pT2, MRD negative disease; however, 29% are MRD positive with a high risk of treatment failure.

The CAPRA score versus sub-types of minimal residual disease to predict biochemical failure after external beam radiotherapy.

INTRODUCTION: External beam radiotherapy is a treatment option for clinically localised prostate cancer; however, some 15% of patients will undergo treatment failure within 5 years. The objective was to compare the Cancer of the Prostate Risk Assessment (CAPRA) score (based on the clinical-pathological findings) and the sub-types of minimal residual disease (MRD) (based on the biological properties of the cancer cells) risk classifications to predict biochemical failure (BF) after external beam radiotherapy. METHODS AND PATIENTS: Clinical-pathological findings were obtained from the prostate biopsy to determine the CAPRA score and used to define low-, intermediate- and high-risk patients. Blood and bone marrow were obtained 3 months after radiotherapy; circulating prostate cells (CPCs) and micro-metastasis were detected using immunocytochemistry with anti-prostate specific antigen. CPCs and micro-metastasis were classified as positive if at least one cell was detected in the sample. Three subgroups were formed Group A (MRD negative), Group B (micro-metastasis positive, CPC negative) and Group C (CPC positive)Patients were followed up for 10 years or until biochemical failure. Biochemical failure free survival (BFFS) curves were constructed using Kaplan-Meier (observed), a flexible parameter model (predicted survival) and the restricted mean survival time (RMST) was calculated for each sub-group. RESULTS: 309 men participated with a median follow-up of 8 years. The risk of biochemical failure increased proportionally with increasing CAPRA score, hazard ratio 1.18 for intermediate and 1.69 for high risk patients. After 10 years, the percentage BFFS and RMST to failure were 74%, 49%, 16% and 9, 7 and 6 years, respectively. The agreement between observed and predicted BFFS was acceptable (Harrell´s C 0.62). The BFFS curves for MRD were different and not proportional, survival curves for men MRD negative and only micro-metastasis were similar up to 5 years, and then there was increasing failure in the micro-metastasis only group. After 10 years, the percentage BFFS and RMST to failure were 95%, 59%, 28% and 10, 9 and 6 years, respectively. The CAPRA score failed to distinguish between Groups A and B, one third of high risk Group C had low risk CAPRA scores. The agreement between observed and predicted BFFS was very good (Harrell´s C 0.92). Minimal residual disease hazard ratios were Group B 1.84 and Group C 4.51. CONCLUSIONS: The MRD prognostic classification is based on the biological characteristics of the tumour cell-microenvironment interaction, to give three groups, MRD negative, only bone marrow micro-metastasis and CPC positive prostate cancer. Differing from the CAPRA score classification the risk of treatment failure changes with time, differentiating between early and late treatment failures and incorporates the concept of dormancy. It proved to be superior to the CAPRA score in predicting biochemical failure and the results need to be confirmed in larger studies.

The expression of matrix-metalloproteinase-2 in bone marrow micro-metastasis is associated with the presence of circulating prostate cells and a worse prognosis in men treated with radical prostatectomy for prostate cancer.

OBJECTIVE: The expression of matrix-metalloproteinase-2 (MMP-2) in the primary tumor is associated with a worse prognosis but little is known at this time regarding the expression in micro-metastasis, the association with circulating prostate cells (CPCs), and outcome. MATERIAL AND METHODS: This was a prospective study of men undergoing radical prostatectomy. Bone marrow and blood samples were taken at one month after surgery. Micro-metastasis and CPCs were identified using immunocytochemistry with anti-prostate specific-antigen and MMP-2 expression determined with anti-MMP-2. Pathological stage, Gleason score, and time to biochemical failure were recorded; meanwhile, Kaplan-Meier biochemical failure-free survival and restricted mean biochemical failure-free survival times for 10 years were determined. RESULTS: A total of 282 men participated, 54 (19%) of whom had micro-metastasis but not CPCs (group B) and 88 (31%) of whom had micro-metastasis and CPCs (group C). Men in group C had a higher frequency of MMP-2 expressing micro-metastasis at 63% versus 12% (p<0.001), and MMP-2 expression in bone marrow micro-metastasis was associated with a higher Gleason score (p<0.05) as well as a higher frequency of and shorter time to treatment failure. Also, a 10-year Kaplan-Meier biochemical failure-free survival rate of 0% versus 7.7% (MMP-2 positive versus negative) and a mean time to biochemical failure of 2.6 versus 4.0 years were recorded. CONCLUSION: The expression of MMP-2 in bone marrow micro-metastasis is associated with a higher Gleason score, the presence of CPCs, and a higher frequency of and shorter time to failure and could be clinically useful for identifying men at high risk of treatment failure.

Minimal Residual Disease Defines the Risk and Time to Biochemical Failure in Patients with Pt2 and Pt3a Prostate Cancer Treated With Radical Prostatectomy: An Observational Prospective Study.

PURPOSE: To compare Gleason score (GS), pathological stage, minimal residual disease (MRD) and outcome after prostatectomy radical for prostate cancer. PATIENTS AND METHODS: 290/357 men with GS 6 or 7 and pT2 or pT3a disease treated with radical prostatectomy participated. Blood and bone marrow were obtained one month after surgery. Circulating prostate cells (CPCs) were detected using differential gel centrifugation and immunocytochemistry with anti PSA, micro-metastasis weas detected using immunocytochemistry with anti-PSA. Biochemical failure free survival (BFFS) and restricted mean survival times (RMST) were calculated according to GS and stage. MRD was classified as negative, patients only positive for micro-metastasis and patients positive for CPCs; BFFS and RMST were calculated according to MRD sub-type. RESULTS: GS7 (HR 3.03) and pT3a (HR 3.68) cancers were associated with a higher failure rate, shorter time to failure and associated with CPC positive MRD (p < 0.001), while G6 and pT2 with MRD negative disease (p<0.001). Men with CPC (+) MRD were at high risk of early treatment failure; 15% BFFS at 10 years, RMST 3.0 years. Men positive for only micro-metastasis were at risk of late failure, 50% BFFS at 10 years, RMST 8.0 years compared with MRD negative patients; 80% BFFS at 10 years, RMST 9.0 years. CONCLUSION: The sub-type of MRD identifies Gleason 6 pT2 patients with a poor prognosis and Gleason 7 pT3a patients with a good prognosis and could be used to classify men according to personal risk characteristics for the use of adjuvant treatment.

Predictive Value of Neutrophil to Lymphocyte Ratio in the Diagnosis of Significant Prostate Cancer at Initial Biopsy: A Comparison with Free Percent Prostate Specific Antigen, Prostate Specific Antigen Density and Primary Circulating Prostate Cells.

INTRODUCTION: An elevated serum PSA is the only biomarker routinely used in screening for prostate cancer to indicate a prostate biopsy. However, it is not specific for prostate cancer and the neutrophil/lymphocyte ratio has been suggested as an alternative. We present a prospective study of men with an elevated PSA and compare the neutrophil/lymphocyte ratio, free percent PSA, PSA density and the presence of circulating prostate cells to detect clinically significant prostate cancer at first biopsy. PATIENTS AND METHODS: Prospective study of consecutive men with a PSA 4-10 ng/ml referred for initial prostate biopsy, the results were compared with the neutrophil/lymphocyte ratio, free percent PSA and PSA density. Circulating prostate cells (CPCs) were detected using immunocytochemistry. The blood sample was taken immediately before the prostate biopsy. RESULTS: 1,223 men participated, 38% (467) of whom had prostate cancer detected, of these 322 were clinically significant. The area under the curves were for neutrophil/lymphocyte ratio, free percent PSA, PSA density and CPC detection were 0.570, 0.785, 0,620 and 0.844 respectively. Sensitivity/specificity were 0.388/0.685, 0.419/0.897, 0.598/0.624 and 0.966/0.786 respectively. The neutrophil/lymphocyte ratio did not differentiate between benign and malignant disease. CONCLUSIONS: The neutrophil/lymphocyte ratio did not discriminate between benign and malignant prostatic disease in patients with a PSA between 4-10ng/ml.

Subtypes of minimal residual disease, association with Gleason score, risk and time to biochemical failure in pT2 prostate cancer treated with radical prostatectomy.

INTRODUCTION: The Gleason score is a strong prognostic factor for treatment failure in pathologically organ-confined prostate cancer (pT2) treated by radical prostatectomy (RP). However, within each Gleason score, there is clinical heterogeneity with respect to treatment outcome, even in patients with the same pathological stage and prostate-specific antigen (PSA) at diagnosis. This may be due to minimal residual disease (MRD) remaining after surgery. We hypothesise that the sub-type of MRD determines the risk of and timing of treatment failure, is a biological classification, and may explain in part clinical heterogeneity. We present a study of pT2 patients treated with RP, the subtypes of MRD for each Gleason score and clinical outcomes. PATIENTS AND METHODS: Patients with Gleason ≤6 (G6) or Gleason 7 (G7) pT2 cancer participated in the study. One month after surgery, blood was taken for circulating prostate cell (CPCs); mononuclear cells were obtained by differential gel centrifugation and identified using immunocytochemistry with anti-PSA. The detection of one CPC/sample was defined as a positive test. Touch-preparations from bone-marrow biopsies were used to detect micro-metastasis using immunocytochemistry with anti-PSA. Biochemical failure was defined as a PSA >0.2 ng/mL. Patients were classified as: Group A MRD negative (CPC and micro-metastasis negative), Group B (only micro-metastasis positive) and Group C (CPC positive). Biochemical failure-free survival (BFFS) using Kaplan-Meier and time to failure using Restricted Mean Survival Time (RMST) after 10 years of follow-up were calculated for each group based on the Gleason score. RESULTS: Of a cohort of 253 men, four were excluded for having Gleason 8 or 9 prostate cancer, leaving a study group of 249 men of whom 52 had G7 prostate cancer. G7 patients had a higher frequency of MRD (69% versus 36%) and worse prognosis. G6 and G7 patients negative for MRD had similar BBFS rates, 98% at 10 years, time to failure 9.9 years. Group C, G6 patients had a higher BFFS and longer time to failure compared to G7 patients (19% versus 5% and 7 versus 3 years). Group B showed similar results up to 5 years, thereafter G6 had a lower BFFS 63% versus 90%. CONCLUSIONS: G7 and G6 pT2 patients have different patterns of MRD and relapse. Risk stratification using MRD sub-types may help to define the need for adjuvant therapy. This needs confirmation with large randomised long-term trials.

Effect of FOLFOX on minimal residual disease in Stage III colon cancer and risk of relapse.

INTRODUCTION: 25% of Stage III colon cancer patients relapse within 5 years due to minimal residual disease (MRD) not eliminated by surgery and chemotherapy. We hypothesise that sub-types of MRD, defined by circulating tumour cells (CTCs) and bone marrow micro-metastasis (mM) have different types and kinetics of relapse. PATIENTS AND METHODS: One month of curative surgery and 1 month after completing six cycles of FOLFOX chemotherapy blood and bone marrow samples were taken to detect CTCs and mM using immunocytochemistry with anti-carcino-embryonic antigen (CEA). Follow up was up to 5 years or disease progression defined as new images on CT scanning. Survival curves using Kaplan-Meier (KM) and Restricted Mean Survival Time (RMST) were calculated for three prognostic groups: CTC and mM negative, CTC negative mM positive, and CTC positive. RESULTS: 76 patients (39 men) participated, mean age 67 years, median follow-up 3.6 years. The response to chemotherapy was heterogeneous and MRD pre-treatment did not predict response to therapy. Of 21 patients MRD (-), 20 remained MRD negative and one patient became mM (+); of 21 patients mM (+), 10 became MRD (-), 8 remained the same and 3 became CTC (+); of the 34 CTC positive, 8 became MRD (-), 8 with only mM, and 18 remained positive.After chemotherapy, 38 patients were negative for CTC and mM, 17 were positive for only mM, and 21 for CTCs. For the whole cohort, the 5 year KM was 58%, the median survival was not reached. For the three prognostic groups, the KM 5-year survivals were 87%, 58%, and 4%, respectively, the median survival for patients MRD negative and mM only was not reached. RMST for the whole cohort was 3.6 years, for the three prognostic groups the RMST was 4.6 years, 4.0 years, and 1.5 years, respectively. Serum CEA was significantly higher pre-surgery in the CTC positive group. There were no significant differences with respect to age or sex between the three groups. CONCLUSIONS: MRD subtypes pre-chemotherapy did not predict treatment response. Post-chemotherapy MRD subtypes were associated with the pattern of failure and time to failure. MRD negative patients had an excellent prognosis with 87% disease-free survival at 5 years. Those with only mM had a similar outcome up to 2 years and then were at increasing risk of late failure. Patients who were CTC positive had a high risk of early failure. MRD subclassification may be useful to define the risk of relapse in Stage III colon cancer patients and warrants further studies with a larger number of patients.

Perfil epidemiológico de la cesárea en Chile en la década 2000-2010 / Epidemiological profile of caesarean section in Chile in the decade 2000-2010

El porcentaje de cesáreas es un indicador de la calidad de la atención obstétrica, y en Chile este porcentaje ha ido en aumento la última década, por lo tanto es perentorio implementar estrategias para este objetivo, tarea no fácil por el carácter multifactorial de este fenómeno.

Cesarean rate is an indicator of the quality of Obstetric and Perinatal care. In Chile this rate has increased over the last decade, so it is imperative to implement strategies to this end, not an easy task because of the multifactorial nature of this phenomenon.

Síndrome de Potter por agenesia renal bilateral y atresia duodenal / Potter syndrome by bilateral renal agenesia and duodenal atresia

Se presentaun caso clínico con diagnóstico antenatal de síndrome de Potter por agenesia renal bilateral asociado a atresia duodenal secundaria a páncreas anular en un feto portador de síndrome de Down con cariotipo 47 XY-21. Se discute el diagnóstico antenatal, manejo obstétrico y perinatal

Diagnóstico ecográfico prenatal de síndrome de Prune-Belly / Echographic prenatal diagnosis of Prune Belly syndrome

Se presenta un caso de Síndrome de Prune-Belly cuyo examen ecográfico pre-natal muestra hidrops, ascitis fetal transitoria y anomalías del sistema urinario. El diagnóstico del Síndrome fue hecho al nacer y confirmado por los exámenes de laboratorio. Se revisa la literatura y se enfatiza la posibilidad de sospechar este diagnóstico, cuando ciertos signos ecográficos aparecen