Radiofrequency ablation in 447 complex unresectable liver tumors: lessons learned.

BACKGROUND: Radiofrequency ablation (RFA) is a promising technique for unresectable hepatic malignancies. We reviewed our RFA experience to identify variables affecting local recurrence. METHODS: Patients undergoing RFA between 1997 and 2001 were reviewed for demographics, tumor size, pathology, diagnosis, recurrence, procedures, survival, and complications. RESULTS: The 447 unresectable liver tumors were ablated in 198 procedures. The 153 patients averaged 61.9 years of age and 1.25 RFA procedures per patient. Follow-up averaged 11 months. Serial ablations were performed in 28 patients, 8 of whom are without evidence of disease. Tumors were most commonly carcinomas of colorectal, hepatocellular, breast, and melanoma histologies. Colorectal carcinomas and hepatomas individually recurred more frequently than all other tumor types combined in univariate analyses (P =.009 and P =.008, respectively). Patients with multiple tumors ablated recurred significantly more frequently (P =.001). Size was also significant in univariate and multivariate analyses (P =.0032 and <.0001, respectively). Eighteen patients experienced 36 complications. CONCLUSIONS: Size has the highest correlation with local recurrence, but multiple tumors and pathology may also predict local recurrence risk. Large, complex lesions can be safely serially ablated, but because of morbidity and recurrence, RFA should not replace resection as the primary treatment of resectable liver tumors.

Cryosurgical ablation of liver tumors in colon cancer patients increases the serum total ganglioside level and then selectively augments antiganglioside IgM.

Cryosurgical ablation (CSA) of tumors induces disruptive necrosis. Necrosis may release tumor gangliosides into circulation and they may augment serum antiganglioside antibodies depending on the nature of gangliosides released. The hypothesis is tested by determining the level of serum total gangliosides (STG) and their antibody titers in the sera of colon cancer patients with cryoablated liver tumors. As controls, we examined the sera of patients who underwent radiofrequency ablation (RFA) and regular surgery (RS), none of which cause disruptive necrosis. The STG level (expressed as lipid-bound sialic acids, LBSA) is higher (p(2)<0.001) in 35 patients (stage IV) than in 38 healthy case-controls (median 23.48 mg/dL, Q-range 7.1 vs 16.04 mg/dL, Q-range 4.5). The mean STG level increased significantly to 31.2+/-6.0mg/dL (p(2)<0.03) after CSA. Concomitantly, the IgM titer against colon cancer-associated gangliosides (GM(2), GD(1a), GT(1b)), increased significantly, but no increase was observed against normal tissue gangliosides (GM(3) or GM(1)). Also after RFA and RS, no such increase was observed either in the level of STG or in IgM titer against tumor gangliosides. The results suggest that CSA-induced necrosis might have acted as an adjuvant, because purified gangliosides without exogenous adjuvants even after repeated immunization failed to elicit antibody response. The post-CSA decline in the STG level correlated with the increase in the antibodies, suggesting a homeostatic role of the antibodies.

A novel lymphatic mapping technique to improve localization and staging of early colon cancer during laparoscopic colectomy.

Encouraging results from our previous studies of sentinel lymph node (SLN) mapping in colorectal cancer (CRC) prompted investigation of its feasibility and accuracy during laparoscopic colectomy for early CRC. Between 1996 and 2000, 14 patients with clinically localized colorectal neoplasms underwent colonoscopic tattooing of the primary site and SLN mapping. In each case 0.5 to 1 cm3 of isosulfan blue dye was injected submucosally via the colonoscope. The blue-stained lymphatics were visualized through the laparoscope and followed to the SLN, which was marked with a clip, and laparoscopic colectomy was completed in the routine fashion. All lymph nodes were examined by hematoxylin and eosin (H&E) staining; in addition each SLN was subjected to focused examination by multisectioning and immunohistochemical staining using cytokeratin antibody. In all 14 patients the primary neoplasm and an SLN were identified laparoscopically. An average of 13.5 total lymph nodes and 1.7 SLNs per patient were identified. The SLN correctly reflected the tumor status of the nodal basin in 93 per cent of the cases. In four cases with unexpected lymphatic drainage, the extent of mesenteric resection was altered. In two cases (14%), nodal involvement was micrometastatic, confined to an SLN, and identified only by immunohistochemical staining. Lymphatic mapping caused no complications and added only 10 to 15 minutes to the overall operative time. Comparison of results in this group with results for a matched group of 14 patients undergoing SLN mapping during open colon resection showed that the laparoscopic technique had similar rates of accuracy and success. These preliminary findings indicate that colonoscopic/laparoscopic SLN mapping during laparoscopic colon resection is a feasible and technically simple means of identifying the primary colorectal neoplasm and its SLN. Focused pathologic examination of this node can upstage CRC and thereby may improve selection of patients for adjuvant chemotherapy.

One hundred consecutive cases of sentinel lymph node mapping in early colorectal carcinoma: detection of missed micrometastases.

Almost one third of patients with "node-negative" colorectal carcinoma (CRC) develop systemic disease. This implies that these patients have occult disease that is inadequately treated by surgery alone. We have coupled sentinel lymph node mapping and a focused pathologic examination to detect occult nodal micrometastases in CRC. Since 1996, sentinel lymph node mapping has been performed in 100 consecutive patients undergoing colectomy for CRC. Peritumoral injection of 0.5 to 1.0 ml of isosulfan blue dye was performed to demonstrate the sentinel node(s). All lymph nodes in the resection specimen were examined by routine hematoxylin and eosin staining. In addition, a focused examination of multiple sections of the sentinel nodes was performed using both hematoxylin and eosin and cytokeratin immunohistochemical analysis (CK-IHC). Overall, lymphatic mapping successfully demonstrated one to four sentinel lymph nodes in 97 (97%) of 100 patients. These sentinel nodes accurately reflected the status of the nodal basin in 92 (95%) of 97 patients. All five of the false negative cases occurred in T3/T4 tumors, and three of the five occurred during the first 30 cases in the experience. Unexpected lymphatic drainage was encountered in eight patients (8%) and altered the operative approach. Twenty-six patients were node positive by routine hematoxylin and eosin staining. Of the remaining 74 patients with hematoxylin and eosin-negative nodes, an additional 18 patients (24%) were upstaged by identification of occult nodal micrometastases that were missed on routine hematoxylin and eosin staining but detected on multiple sections (n = 5) or by CK-IHC (n = 13). The sentinel lymph nodes were the only positive nodes in 19 cases. Sentinel lymph node mapping may be performed in CRC with a high degree of success and accuracy. A focused pathologic examination of the sentinel node detects micrometastatic disease that is missed by conventional techniques in a significant proportion of patients with early CRC. Further studies are necessary to elucidate the clinical relevance of these micrometastases.

Systemic irinotecan and regional floxuridine after hepatic cytoreduction in 185 patients with unresectable colorectal cancer metastases.

BACKGROUND: This study evaluated our 7-year experience treating unresectable colorectal cancer (CRC) hepatic metastases refractory to systemic 5-fluorouracil. METHODS: A total of 185 patients with unresectable 5-fluorouracil-resistant CRC hepatic metastases underwent surgical cytoreduction. Postoperatively patients received either hepatic arterial floxuridine (FUDR) and systemic irinotecan as part of a phase II trial or no further treatment. RESULTS: Of the 185 patients undergoing surgical cytoreduction, 71 patients received adjuvant irinotecan/FUDR. There were no appreciable differences in synchronous or metachronous lesions or the median number or size of lesions between treatment groups. At a median follow-up of 20 months, there were fewer recurrences in patients treated with postoperative irinotecan/FUDR compared with untreated patients for both hepatic and extrahepatic recurrences. Progression-free and overall survival were longer for patients who received irinotecan/FUDR compared with patients who did not receive adjuvant therapy. The 2-year survival rate was significantly better for patients receiving adjuvant therapy compared with patients receiving no additional treatment. Predictors of improved survival included a preoperative carcinoembryonic antigen level <100 ng/dl, >30% postoperative reduction in carcinoembryonic antigen level, and adjuvant therapy. CONCLUSIONS: Combined therapy with irinotecan/FUDR may improve the results of surgical cytoreduction for unresectable CRC hepatic metastases.

Serum total gangliosides and TA90-IC levels: novel immunologic markers in colorectal cancer.

BACKGROUND: Because of the challenge in defining prognostic markers predictive of recurrence or progression, carcinoembryonic antigen (CEA) remains the most frequently used marker in colorectal cancer, despite its low sensitivity. We hypothesized that TA90-IC status and serum ganglioside levels might be useful markers and might be of prognostic significance in colorectal cancer. METHODS: Serum samples from 68 patients undergoing surgical treatment for histologically proven colorectal cancer were analyzed for the presence of CEA, serum gangliosides, and TA90-IC. Forty-one patients had node-negative disease, whereas 27 patients had limited metastatic disease. The intent was curative resection, even for patients with metastatic disease. Cryopreserved serum specimens were analyzed in a blinded fashion for total serum ganglioside levels (by an assay that detects lipid-associated sialic acids), for CEA, and for TA90-IC (by a murine monoclonal antibody-based enzyme-linked immunosorbent assay). A positive value for TA90-IC levels was defined as an optical density (OD) of more than 0.410 at 405 nm. RESULTS: Serum ganglioside levels were elevated more frequently than CEA concentrations (84% vs 44%). The combination of serum ganglioside and CEA values was more sensitive (88%) than CEA value alone (44%) in identifying patients with early-stage colorectal cancer. TA90-IC levels were elevated more frequently than CEA concentrations (56% vs 32%). The combination of TA90-IC and CEA values was more sensitive (72%) than CEA value alone (32%) in identifying patients with advanced-stage colorectal cancer. At an enzyme-linked immunosorbent assay cutoff level of 0.410, 15 (56%) patients had positive TA90-IC values. Fourteen patients alive with residual disease had a median OD TA90-IC level of 0.879, and only three patients had levels below the OD cutoff value of 0.410. Thirteen patients with no evidence of disease had a median level of 0.277, and only four patients had OD levels > or = 0.410. TA90-IC was significantly higher in the alive with residual disease patients than those rendered no evidence of disease (P = 0.02). CONCLUSIONS: We speculate that a multiple-marker analysis that combines CEA values with serum ganglioside and TA90-IC values may be more sensitive than CEA value alone for detecting colorectal cancer. The potential prognostic significance of TA90-IC status in advanced disease warrants further investigation.