Chemotherapy has also an effect on primary tumor in colon carcinoma.
ABSTRACT This study characterizes the histological effect of chemotherapy (CT) on primary colonic tumors.
Between 2000 and 2006, 38 patients with stage IV colon cancer underwent resection of the primary, after chemotherapy (CT group, n = 16) or without preoperative CT (control group, n = 22). For all primary tumors, histological analysis included: fibrosis, acellular necrosis, acellular mucin pools, lymphoplasmacytic infiltration, and changes at tumor surface. Tumor regression grade (TRG) was determined by the amount of residual tumor cells and was graded from 1 to 5.
No patient had complete histological response. Major histological tumor regression (TRG2) was observed in 70% of patients treated by CT and none of the not treated patients (P < 0.0001). Fibrosis, acellular necrosis, and surface changes were significantly increased in the CT group. TRG in the primary was comparable to the TRG in the corresponding liver metastases for 7/9 patients who underwent both colonic and hepatic resection after CT.
CT induces major histological response in 70% of colon cancers. Response to CT in the primary and the corresponding liver metastases are correlated. These results support a policy of initial CT management for stage IV colon cancer and may warrant future studies of neoadjuvant CT in locally advanced colon carcinomas.
Article: Neoadjuvant chemotherapy in patients with stage IV colorectal cancer: a comparison of histological response in liver metastases, primary tumors, and regional lymph nodes.[show abstract] [hide abstract]
ABSTRACT: We report the histopathological results of a novel "inversed" strategy designed to manage patients with colorectal cancer (CRC) who have synchronous liver metastases by using chemotherapy first, liver surgery second, and resection of the primary tumor as a final step. This study was designed to compare the response to chemotherapy in liver metastases, primary tumors, and locoregional lymph nodes. Twenty-nine patients with stage IV CRC received a combination of oxaliplatin, irinotecan, 5-fluorouracil, and leucovorin (OCFL) for 3-4 months. Histological response to chemotherapy was assessed by using a tumor regression grading (TRG) score based on presence of residual tumor cells and extent of fibrosis. Median age of patients was 56 (range, 37-69) years. Primary tumor location was right colon (n = 5), left colon (n = 7), and rectum (n = 17 patients). TRG scores correlated across disease sites (Spearman correlation coefficients for TRG in the primary tumor and lymph nodes was 0.59 [P = 0.005]; for the primary tumor and metastases 0.44 [P = 0.021]; and for lymph nodes and metastases 0.58 [P = 0.006]). Complete absence or poor tumor response (TRG4/5) was significantly more frequent in primary tumors (35.7%) and locoregional lymph nodes (38%) than in liver metastases (6.9%; McNemar test, P = 0.02). Two patients had a complete pathologic response (pT0N0M0). In patients with stage IV colorectal cancer, liver metastases exhibit a better histological response than primary tumors to OCFL neoadjuvant chemotherapy.Annals of Surgical Oncology 10/2010; 17(10):2714-9. · 4.17 Impact Factor