Therapeutic and prognostic significance of tumor bud density in resected synchronous and metachronous liver metastases in colorectal cancer

Tumorsko pupljenje (TP) u karcinomu je morfološki fenomen koji predstavlja pojavu pojedinačnih ili malih grupa dediferentovanih tumorskih ćelija koje se na invazivnom frontu karcinoma odvajaju od glavne tumorske mase. Kod metastatskog kolorektalnog karcinoma (KRK) definitivno ne možemo odrediti pravi doprinos TP. Cilj je bio da se ispita terapijski patohistološki odgovor na primenjeni hemioterapijski režim, prognostički i nezavisni negativni značaj TP , kao i korelacija TP i terapijskog odgovora histološke regresije kod R0 reseciranih sinhronih i metahronih jetrenih metastaza KRK, koji su primali polihemioterapije po protokolu Folfox 4, sa i bez VEGF inhibitora – bevacizumaba (AV). Studija je prospektivno – retrospektivna i obuhvata 77 bolesnika oba pola, uzrasta preko 18 godina, sa patohistološki verifikovanim jetrenim metastazama KRK, koji su operisani u Institutu za onkologiju Vojvodine u periodu od 1. maja 2007. do 1. juna 2017. godine. Od ukupno 120 bolesnika, njih 77 je ispunjavalo sledeće kriterijume: da je histološki dokazan metastatski adenokarcinom kolorektuma sa R0 resekcijom i da su preoperativno dobijali HT sa biološkom terapijom ili bez nje. Bolesnike smo podelili u dve grupe: KRK – sinhrona metastatska bolest i KRK – metahrona metastatska bolest. Nakon selekcije bolesnika, rađena je mikroskopska analiza rutinskih histoloških i imunohistohemijskih preparata i određivana je gustina TP, histološka regresija prema mTRG bodovanju komparirala se sa radiološkim odgovorom po RECIST-u. Događaji od interesa u kliničkom toku bolesti jesu progresija nakon hirurškog zahvata jetrenih metastaza i ukupno preživljavanje u periodu od 24 meseca. Nema statistički značajne patohistološke razlike u učestalosti lošijeg terapijskog odgovora (mTRG 3 – 5) u odnosu na bolji terapijski odgovor (mTRG 1, 2) između bolesnika sa sinhronom i metahronom metastatskom bolešću KRK, koji su lečeni hemioterapijskim protokolom Folfox4: 13 (76,5%) vs. 13 (72,2%); p = 0,774. Kod bolesnika sa sinhronim metastazama KRK, lečenih hemioterapijskim protokolom Folfox 4, postoji statistički značajna razlika u učestalosti preživljavanja tokom dve godine, i to kod bolesnika sa malom u odnosu na one sa velikom gustinom TP: 10 (90,9%) vs. 5 (55,6%); p = 0,049. Kod tih bolesnika, lečenih hemioterapijskim protokolom Folfox4/AV, postoji statistički značajna razlika u učestalosti preživljavanja tokom dve godine, i to kod bolesnika sa malom u odnosu na one sa velikom gustinom TP: 9 (100%) vs. 6 (33,3%); p = 0,048. Kod bolesnika sa metahronim metastazama KRK lečenih hemioterapijskim protokolom Folfox4, sa i bez AV, nema statistički značajne razlike u učestalosti preživljavanja tokom dve godine u odnosu na gustinu TP. Kod bolesnika sa sinhronim i metahronim metastazama KRK nema statistički značajne razlike u učestalosti lošijeg histološkog odgovora na terapiju (mTRG 3 – 5) kod onih sa malom u odnosu na one sa velikom gustinom (TP): (8 (50%) vs. 15 (78,9%); p = 0,072 i TP: 8 (80%) vs. 13 (72,2%); p = 0,649). Kod bolesnika sa sinhronim metastazama KRK lečenih hemioterapijskim protokolom Folfox4, sa i bez AV, postoji statistički značajna razlika u učestalosti preživljavanja tokom dve godine u odnosu na gustinu TP. Takođe, kod tih bolesnika velika gustina TP je nezavistan negativan faktor prognoze u odnosu na date terapijske režime, što se vidi u preživljavanju tokom dve godine.Tumor budding (TB) in cancer is a morphological phenomenon representing the appearance of single or small groups of dedifferentiated tumor cells that separate from the main tumor mass on the invasive front of cancer. In metastatic colorectal cancer (MCC), the true contribution of TB cannot be determined. The aim was to investigate the therapeutic pathohistological response to the applied chemotherapy, the prognostic and independent negative significance of TB, as well as the correlation of TB and the therapeutic response of histological regression in R0 resectable synchronous and metachronous liver metastases of MCC receiving polychemotherapy according to the Folfox 4 protocol, with and without VEGF inhibitors - bevacizumab (AV). The research was conducted as a prospective – retrospective study that included 77 patients of both sex, over 18 years of age, with pathohistologically verified MCC liver metastases, who underwent surgery at the Institute of Oncology of Vojvodina from 1st May 2007 until 1st June 2017. From 120 patients, 77 patients met the following criteria: they had histologically proven metastatic colorectal adenocarcinoma with R0 resection and also received preoperative chemotherapy with or without biological therapy. The patients were divided into two groups: MCC - synchronous metastatic disease and MCC - metachronous metastatic disease. After the patient selection, microscopic analysis of routine histological and immunohistochemical preparations was performed, the density of TB was determined, and the histological regression according to mTRG scoring was compared with a radiologic response according to the RECIST. The events of interest in the clinical course of the disease were the progression of hepatic metastases after surgery and overall survival during 24 months. There is no statistically significant pathohistological difference in the incidence of worse therapeutic response (mTRG 3 - 5) compared to the better therapeutic response (mTRG 1, 2) between patients with synchronous and metachronous MCC who were treated with the Folfox4 chemotherapy protocol: 13 (76.5%) vs. 13 (72.2%); p = 0.774. In patients with synchronous MCC metastases treated with the Folfox 4 chemotherapy protocol, there was a statistically significant difference in the survival rates during two years particularly in patients with low versus high TB density: 10 (90.9%) vs. 5 (55.6%); p = 0.049. In those patients who were treated with the Folfox4 / AV chemotherapy protocol, there was a statistically significant difference in survival rates during two years particularly in patients with low TB density in reference to those with high: 9 (100%) vs. 6 (33.3%); p = 0.048. In patients with metachronous MCC metastases who were treated with the Folfox4 chemotherapy protocol, with and without AV, there was no statistically significant difference in survival rate during two years when referring to the TB density. In patients with synchronous and metachronous metastases, MCC has no statistically significant difference in the incidence of worse histological response to therapy (mTRG 3 - 5) in patients with low TB density versus the ones with high density (TB): (8 (50%) vs. 15 (78.9%); p = 0.072 and TP: 8 (80%) vs. 13 (72.2%); p = 0.649). In patients with synchronous MCC metastases who were treated with the Folfox4 chemotherapy protocol, with and without AV, there is a statistically significant difference in survival rates during a two-year follow up when referring to the TB density. Also, the high density of TB is an independent negative prognostic factor in these patients in reference to the given therapeutic regimens, as seen in the two-year survival rate