Gastric cancer: histological response of tumor and metastatic lymph nodes for perioperative chemotherapy.

BACKGROUND: Gastric cancer is the fourth cancer most common in the world and the second cause of cancer-related deaths. Perioperative chemotherapy may reduce tumor burden and decrease lymph node invasion, improving R0 resections rates. On the other hand, administered before surgery, chemotherapy may cause fibrosis and tissue edema, with potential increase of surgical difficulty and in the number of post-operative complications. Therefore, we aim to investigate the effect of perioperative chemotherapy for tumor burden and metastatic lymph nodes of gastric cancer. METHODS: Retrospective analysis of all patients submitted to perioperative chemotherapy and surgery, between January 2010 and June 2020, which showed lymph node regression and tumor regression (Becker's classification). RESULTS: A total of 112 patients with an average age of 61.9 years were analyzed. About 90.2% completed three cycles of perioperative chemotherapy. Good tumor response to chemotherapy (<10% residual tumor) was achieved in 21.3% of patients. Only three patients obtained a complete pathological response. A median lymph node response of 33.3% was achieved in our series. CONCLUSION: Despite no evident outstanding regression rate was observed, perioperative chemotherapy seems to be useful in obtaining a R0 resection in gastric cancer, even in advanced gastric cancer.

INTRODUCCIÓN: El cáncer de estómago es el cuarto tipo de cáncer más común y la segunda causa de muerte relacionada con el cáncer. La quimioterapia perioperatoria puede reducir la carga tumoral y disminuir la invasión de los ganglios linfáticos. Por otro lado, administrada antes de la cirugía, la quimioterapia puede causar fibrosis y edema tisular, aumentando potencialmente la dificultad quirúrgica y el número de complicaciones posoperatorias. Nuestro objetivo es investigar el efecto de la quimioterapia perioperatoria sobre la carga tumoral y los ganglios metastásicos en el cáncer gástrico. MÉTODOS: Análisis retrospectivo de todos los pacientes sometidos a quimioterapia y cirugía, entre enero de 2010 y junio de 2020. RESULTADOS: Se analizaron 112 pacientes con una edad media de 61.9 años. El 90.2% completó 3 ciclos de quimioterapia perioperatoria. Se logró una buena respuesta tumoral a la quimioterapia (< 10% de tumor residual) en el 21.3% de los pacientes. Tres pacientes lograron una respuesta patológica completa. En nuestra serie se logró una mediana de respuesta de los ganglios linfáticos del 33.3%. CONCLUSIÓN: Aunque no se observó una tasa de regresión manifiesta, la quimioterapia perioperatoria parece ser útil para lograr una resección R0 en el cáncer gástrico, incluso en el cáncer gástrico avanzado.

A real-life analysis on the indications and prognostic relevance of perioperative chemotherapy in locally advanced resectable gastric adenocarcinoma.

BACKGROUND AND PURPOSE: Perioperative chemotherapy (periCTX) based on the "MAGIC" scheme has become a standard treatment in Europe for locally advanced oesophagogastric cancer. We assessed implementation and long-term oncological outcomes of MAGIC periCTX for locally advanced gastric cancer. METHODS: Population-based cohort study of all patients with locally advanced gastric cancer undergoing surgical resection with curative intent in Catalonia and Navarra (the first two autonomous communities included in the EURECCA Upper GI Spanish Working Group) between January 2011 and December 2013. The main variable was the percentage of patients treated with MAGIC periCTX. Kaplan-Meier analysis and Cox proportional hazards model were used to assess the survival benefit of periCTX. RESULTS: Among 814 patients, 217 (26.6%) received periCTX (especially patients more likely to receive it: aged < 70 years, with proximal tumors, low anesthetic risk, and cT3-4/cN+ clinical stage). 35% did not complete perioperative chemotherapy, with no relationship with age. PeriCTX showed no effect on postoperative morbimortality. Histological tumor regression was more often absent or poor (38.2%) than total or almost total (27.8%), although clinico-pathological lymph-node downstaging was higher than expected by staging inaccuracy (38.7% vs. 24.2%). PeriCTX was associated with a better survival only in cT3-4 and cN+ patients, showing less prognostic relevance than optimal oncological surgery with D2 lymphadenectomy. CONCLUSIONS: Only 26.6% of locally advanced resectable gastric cancer patients received PeriCTX. Pathological response was poor, although some degree of nodal downstaging was observed. Survival benefit of periCTX was limited to cT3-4 and cN+ patients, being less relevant than D2 lymphadenectomy.

Prognostic impact of K-RAS mutational status and primary tumor location in patients undergoing resection for colorectal cancer liver metastases: an update.

Aim: To determine the impact of KRAS mutation status on survival in patients undergoing surgery for colorectal liver metastases (CLM). Patients & methods: Patients with resected CLM and KRAS mutations. Survival was compared between mt-KRAS and wt-KRAS. Results: Of 662 patients, 174 (26.3%) were mt-KRAS and 488 (73.7%) wt-KRAS. mt-KRAS patients had significantly lower recurrence-free survival (HR: 1.42; 95% CI: 1.10-1.84). There were no differences between the groups for sidedness. Poorer survival was associated with mt-KRAS with positive lymph nodes, >1 metastases, tumors >5 cm, synchronous tumors and R1-R2. Conclusion: KRAS mutation status can help predict recurrence-free survival. Primary tumor location was not a prognostic factor after resection. KRAS mutation status can help design a multidisciplinary approach after curative resection of CLM.

Adenocarcinoma gástrico y tumor estromal del estómago sincrónico incidental / Gastric adenocarcinoma and incidental synchronous incidental gastrointestinal stromal tumor

Se presenta el caso de un paciente masculino de 73 años de edad operado por adenocarcinoma del antro gástrico. Se practicó gastrectomía subtotal distal más linfadenectomía D2. Durante el examen anatomopatológico de la pieza quirúrgica se encontró otro tumor pequeño en el espesor de la pared del antro cubierto por mucosa normal, separado del adenocarcinoma. El análisis histológico confirmó otra neoplasia incidental sincrónica, un tumor del estroma gastrointestinal de tipo fusiforme, positivo para el marcador tumoral CD117. El objetivo del trabajo es presentar esta asociación tumoral sincrónica, revisar sus características y las teorías etiopatogénicas actuales de esta condición sincrónica según la literatura especializada(AU)

A case is presented of a 73-year-old male patient who was operated for a gastric adenocarcinoma of the antrum. A distal subtotal gastrectomy plus D2 lymphadenectomy were practiced. During the anatomic and pathologic examination of the surgical piece, a second tiny tumor was found in the wall of the antrum and that was covered with a normal mucosa separated from the adenocarcinoma. The histologic examination confirmed another synchronous incidental neoplasm, a spindle-cell gastrointestinal stromal tumor, positive for the tumor marker CD117. This paper is aimed at presenting synchronous tumor entity, to review its characteristics and the current etiologic and pathogenic theories of this synchronic condition according to the specialized literature(AU)