Outcome in disappearing colorectal cancer liver metastases during oxaliplatin-based chemotherapy

Abstract

Abstract. Some colorectal cancer liver metastases (CLMs) disappear on serial imaging during chemotherapy and the optimal treatment strategy for such lesions remains undetermined. The purpose of this study was to investigate the outcome in disappearing CLMs, as few studies have focused on this topic, with conflicting results. Among 125 patients with CLMs treated with modified FOLFOX6 with or without bevacizumab, those in whom all CLMs disappeared on computed tomography were identified. Recurrence of such disappearing lesions in situ was examined on a tumor-by-tumor basis. Five (4%) patients with a total of 44 CLMs met the evaluation criteria. The median number of CLMs prior to chemotherapy was 8 (range, 2-16). The median maximal diameter of the CLMs was 1.8 cm (range, 1.0-2.4). The median time-todisappearance of all eligible lesions was 6.5 months (range, 4.5-7.5). Histological examination of scar lesions on the liver surface revealed no viable cancer cells. Two lesions were surgically resected. During clinical follow-up of the remaining 42 lesions, in situ recurrence was observed in 8. The cumulative 1-, 2-and 3-year rates of relapse in situ were 9.1, 9.1 and 31.1%, respectively. Given the low risk of recurrence in situ, the results suggest that the sites of disappearing CLMs may be left unresected but should be carefully monitored during follow-up, with resection an option if the lesion should recur. However, to validate such a treatment strategy, further investigation with a larger series of patients is warranted. IntroductionRecent advances in chemotherapy have resulted in an increasing number of patients with colorectal cancer liver metastases (CLMs) being treated with systemic chemotherapy prior to hepatic metastasectomy, either as neoadjuvant treatment for initially resectable lesions or in an attempt to make unresectable lesions resectable. When used as first-line chemotherapy for CLMs, new and effective regimens, including 5-fluorouracil (5-FU)/leucovorin (LV), irinotecan and oxaliplatin in combination with targeted agents, have yielded a complete response in 1 to 9% of patients with CLMs (1-3). The optimal treatment strategy in such cases, however, remains to be determined as, to the best of our knowledge, little research has been carried out on this topic and the results thus far have been conflicting. Patients and methodsPatients. The study protocol conformed to the standards of good practice and ethics of our institution. Informed consent was obtained from the individuals included in the study. A retrospective review of all consecutive patients who had been diagnosed with CLM and who were treated with first-line oxaliplatin-based chemotherapy (modified FOLFOX6; mFOLFOX6) with or without bevacizumab between January 2006 and December 2010 was carried out. The mFOLFOX6 regimen comprised intravenous infusion of oxaliplatin (80 mg/m 2 ) over 2 h, followed by rapid intravenous bolus infusion of 5-FU (400 mg/m 2 ) for 5 min and continuous intravenous infusion of 5-FU (2,400 mg/m 2 ) over 46 h. This regimen ...

The Influence of Radiological “Disappearing Lesions” on the Efficacy and Prognosis of Patients with Colorectal Liver Metastases Undergoing Conversion Therapy

“…Conversion therapy for initially unresectable liver metastasis of CRC patients has a significant role. Some studies have claimed that in the process of conversion therapy, some liver lesions of 9-37% patients with CRLM are not visible on the radiology, known as DLM [2,6,[21][22][23]. This study shows DLM in 31.0% of 113 patients, similar to the previous studies.…”

Clinical implications of disappearing colorectal liver metastases have changed in the era of hepatocyte-specific MRI and contrast-enhanced intraoperative ultrasonography

“…These results suggest that DLMs should be resected when detected by sequential inspection using EOB-MRI and CE-IOUS that visualize DLMs containing residual tumors. It has been controversial whether to resect all DLMs because the reported incidence of viable DLMs is variable, ranging from 0% to 80%, 1,2,4,15,16 and because no diagnostic modalities that specify viable DLMs have been available. The authors have previously reported 97% accuracy of CE-IOUS to identify histologically confirmed CRLMs among tumors detected on imaging studies, 11 and the current study went a step further by showing 83% accuracy of CE-IOUS to identify viable DLMs among DLMs on CE-CT.…”

Management of disappearing colorectal liver metastases: an international survey

“…29,30 Though a complete radiologic response does not guarantee a durable or complete pathologic response, there are some studies that report a complete pathological response or no evidence of in situ recurrence ranging from 16.7 to 80.5%. 7,19,23,31 The findings of this survey allow for surgeons to place their own practices in the context of their colleagues in many different countries and continents and perhaps to adjust their practices to align with what is being done in most centers. Most significantly, only 47% of surgeons in this survey use MRI for preoperative planning though there is evolving data that MRI is superior to CT or PET.…”