Tumor ablation with radio-frequency energy

Tumor ablation by using radio-frequency energy has begun to receive increased attention as an effective minimally invasive approach for the treatment of patients with a variety of primary and secondary malignant neoplasms. To date, these techniques have been used to treat tumors located in the brain, musculoskeletal system, thyroid and parathyroid glands, pancreas, kidney, lung, and breast; however, liver tumor ablation has received the greatest attention and has been the subject of a large number of published reports. In this article, the authors review the technical developments and early laboratory results obtained with radio-frequency ablation techniques, describe some of the early clinical applications of these techniques, and conclude with a discussion of challenges and opportunities for the future.

Surgery for colorectal liver metastases with hepatic lymph node involvement: a systematic review

BACKGROUND

Liver resection for colorectal metastases is the only known treatment associated with long-term survival; extrahepatic disease is usually considered a contraindication to such treatment. However, some surgeons do not regard spread to the hepatic lymph nodes as a contraindication provided that these nodes can be excised adequately. A systematic review of the literature was undertaken to address this issue.

METHODS

An electronic search using Medline, Cancerlit and Embase databases was performed for studies reporting liver resection for colorectal metastases from 1964 to 1999. Data were extracted from papers reporting outcome for patients with positive hepatic nodes and analysed according to predetermined criteria.

RESULTS

Fifteen studies were identified that gave survival data on 145 node-positive patients. Five patients were reported to have survived 5 years after liver resection; one was disease free, two had recurrent disease and the disease status was not described in the remaining two. Five studies containing 83 patients specified a formal lymph node dissection as part of the surgical procedure and four of the five node-positive 5-year survivors were from these studies.

CONCLUSION

There are few 5-year survivors after liver resection, with or without lymph node dissection, for colorectal hepatic metastases involving the hepatic lymph nodes.

A prospective analysis of the cephalic vein cutdown approach for chronic indwelling central venous access in 100 consecutive cancer patients

BACKGROUND

Chronic indwelling central venous access devices (CICVAD) generally are placed by the percutaneous subclavian vein approach. The cephalic vein cutdown approach is used only infrequently. Although the technique has been well described, few prospective data are available on the cephalic vein cutdown approach.

METHODS

From September 9, 1998, to July 20, 1999, the cephalic vein cutdown approach was attempted in 100 consecutive cancer patients taken to the operating room with the intention of placing CICVAD. Median patient age was 54.5 years (range 18-88), with 46 men and 54 women. Twenty-five patients had gastrointestinal malignancies, 17 had breast cancer, 15 had lymphoma, 13 had lung cancer, 12 had leukemia, 5 had multiple myeloma, and 13 had other malignancies. Patients were followed prospectively for immediate and long-term outcome.

RESULTS

CICVAD placement via the cephalic vein cutdown approach was successful in 82 patients; the remaining 18 patients required conversion to a percutaneous subclavian vein approach. The reasons for inability to place CICVAD via cephalic vein cutdown approach were a cephalic vein that was too small (10 patients), an absent cephalic vein (7 patients), and inability to traverse the angle of insertion of the cephalic vein into the subclavian vein (1 patient). There were 56 subcutaneous ports and 26 tunneled catheters. Median operating time was 44 minutes (range, 26-79 minutes). No postoperative pneumothorax occurred. Median catheter duration was 198 days (range, 0-513 days). Long-term complications included catheter-related bacteremia (6%), site infection (2%), deep venous thrombosis (5%), port pocket hematoma (1%), and superior vena cava stricture (1%). Thirty-seven percent of patients have died since CICVAD placement. Twenty-nine percent of the CICVADs have been removed.

CONCLUSIONS

The cephalic vein cutdown approach was successful in 82% of patients. This approach is a safe and useful alternative to the percutaneous subclavian vein approach.

Hepatic arterial infusion of chemotherapy after resection of hepatic metastases from colorectal cancer

BACKGROUND

Two years after undergoing resection of liver metastases from colorectal cancer, about 65 percent of patients are alive and 25 percent are free of detectable disease. We tried to improve these outcomes by treating patients with hepatic arterial infusion of floxuridine plus systemic fluorouracil after liver resection.

METHODS

We randomly assigned 156 patients at the time of resection of hepatic metastases from colorectal cancer to receive six cycles of hepatic arterial infusion with floxuridine and dexamethasone plus intravenous fluorouracil, with or without leucovorin, or six weeks of similar systemic therapy alone. Patients were stratified according to previous treatment and the number of liver metastases identified at operation. The study end points were overall survival, survival without recurrence of hepatic metastases, and survival without any metastases at two years.

RESULTS

The actuarial rate of overall survival at two years was 86 percent in the group treated with local plus systemic chemotherapy and 72 percent in the group given systemic therapy alone (P=0.03). The median survival was 72.2 months in the combined-therapy group and 59.3 months in the monotherapy group, with a median follow-up of 62.7 months. After two years, the rates of survival free of hepatic recurrence were 90 percent in the monotherapy group and 60 percent in the monotherapy group (P<0.001), and the respective rates of progression-free survival were 57 percent and 42 percent (P=0.07). At two years, the risk ratio for death was 2.34 among patients treated with systemic therapy alone, as compared with patients who received combined therapy (95 percent confidence interval, 1.10 to 4.98; P=0.027), after adjustment for important variables. The rates of adverse effects of at least moderate severity were similar in the two groups, except for a higher frequency of diarrhea and hepatic effects in the combined-therapy group.

CONCLUSIONS

For patients who undergo resection of liver metastases from colorectal cancer, postoperative treatment with a combination of hepatic arterial infusion of floxuridine and intravenous fluorouracil improves the outcome at two years.

Current treatment for colorectal cancer metastatic to the liver

Surgery is currently the only available treatment option which offers the potential for cure for patients with liver metastases from colorectal cancer. Of those who undergo a potentially curative operation for their primary tumour but subsequently recur, almost 80% will develop evidence of metastatic disease within the liver. Greater experience and improvements in technique in liver surgery, with an increasingly aggressive surgical approach to metastatic colorectal cancer to the liver, has resulted in prolonged disease-free survival with 5-year rates varying from 21% to 48%. In order to increase these numbers further and to treat patients not eligible for surgical therapy, new treatment modalities and strategies have been developed. This review presents an update of the current treatment for colorectal disease metastatic to the liver.

Surgical margin in hepatic resection for colorectal metastasis: a critical and improvable determinant of outcome

OBJECTIVE

To update the analysis of technical and biologic factors related to hepatic resection for colorectal metastasis in a large single-institution series to identify important prognostic indicators and patterns of failure.

SUMMARY BACKGROUND DATA

Surgical therapy for colorectal carcinoma metastatic to the liver is the only potentially curable treatment. Careful patient selection of those with resectable liver-only metastatic disease is crucial to the success of surgical therapy.

METHODS

Two hundred forty-four consecutive patients undergoing curative hepatic resection for metastatic colorectal carcinoma were analyzed retrospectively. Variables examined included sex, stage of primary lesion, size of liver lesion(s), number of lesions, disease-free interval, ploidy, differentiation, preoperative carcinoembryonic antigen level, and operative factors such as resection margin, use of cryotherapy, intraoperative ultrasound, and blood loss.

RESULTS

Surgical margin, number of lesions, and carcinoembryonic antigen (CEA) levels significantly control prognosis. Patients with only one or two liver lesions, a 1-cm surgical margin, and low CEA levels have a 5-year disease-free survival rate of more than 30%. Disease-free interval, original stage, bilobar involvement, size of metastasis, differentiation, and ploidy were not significant predictors of recurrence. The pattern of failure correlates with surgical margin. Routine use of intraoperative ultrasound resulted in an increased incidence of negative surgical margin during the period examined.

CONCLUSIONS

Surgical resection or cryotherapy of hepatic metastasis from colorectal cancer is safe and curable in appropriately selected patients. Biologic factors, such as number of lesions and carcinoembryonic antigen levels, determine potential curability, and surgical margin governs the patterns of failure and outcome in potentially curable patients. Optimization of selection criteria and surgical resection margins will improve outcome.

A study of prognostic factors for hepatic resection for colorectal metastases

BACKGROUND

Liver resection is accepted treatment for selected patients with colon cancer metastatic to the liver. There remains some controversy regarding the selection criteria, particularly which preoperative features are useful predictors of long survival postresection.

METHODS

One hundred and twenty-three patients who had liver resection for colorectal metastases on the Hepato Pancreatic Biliary Service at The Toronto Hospital between August 1977 and June 1993 were studied. Seventy-seven had solitary lesions, 15 had single lesions with satellite nodules, and 31 had multiple lesions. Synchronous liver metastases were found in 40 patients and 83 patients had metachronous lesions. Fifty-one patients had formal lobectomies and 21 had extended lobectomies.

RESULTS

Postoperative complications were seen in 28% of patients, but there were no operative or postoperative deaths. Overall actuarial 5-year survival was 34%. There was a significant difference in survival according to the number of metastases. Patients with single lesions had a 5-year survival of 47% compared with 16% for single lesions with satellite nodules, and 17% for multiple lesions. There were no significant differences in survival based on age, sex, synchronous versus metachronous lesions, status of lymph nodes at the time of original surgery, intraoperative blood replacement, or size of tumor.

CONCLUSIONS

An aggressive approach to the surgical management of colorectal liver metastases is possible with low risk in centers specializing in liver surgery, and results in prolonged survival in one third of patients. The most reliable predictor of long-term survival is the number of metastases in the liver.

Invasive therapy of metastatic colorectal cancer to the liver

Resection, when possible, is still the best hope for cure of colorectal metastasis to the liver. Poor prognostic indicators for survival include heavy tumor burden, the presence of extrahepatic disease, synchronous metastasis, and the inability to perform resection with a 1-cm margin. Questionable poor prognostic indicators include multiple metastases (more than three), bilobar disease, and the need to transfuse patients during resection. Preoperatively, a patient must be evaluated for the extent of liver disease and the presence of extrahepatic disease with a CT of the abdomen and routine studies of the chest. Intraoperatively, a surgeon should be able to perform or obtain ultrasonography of the liver to detect occult metastases and delineate anatomy. The surgeon should be experienced in wedge, segmental, and lobar resection. Equipment for cryotherapy and arterial infusion devices should be available, and staff experienced in these modalities should be present. If all of these factors are present, the options for the invasive treatment of colorectal metastasis to the liver can be carried out in a manner that should provide the most benefit at a low morbidity to this population of patients.

Serum tumor markers in colorectal cancer staging, grading, and follow-up

Early diagnosis of colorectal cancer, a frequent neoplasia in industrialized countries, permits curative surgery. In this study we assessed the clinical role of serum tumor markers determination in diagnosing, staging, and grading colorectal cancer; the role of carcinoembryonic antigen (CEA), CA 19-9, tissue polypeptide antigen (TPA) and CA 72-4 in colorectal cancer follow-up was also assessed. In 114 patients with colorectal cancer, the oncofetal antigen CEA was compared with the membrane-associated glycoproteins CA 19-9, CA 242, and CA 72-4 and with the cytokeratins TPA, tissue polypeptide-specific antigen (TPS) and tissue polypeptide monoclonal antigen (TPM). Overall, the most sensitive indices were TPA and TPS (67% and 70%, respectively). Tumor stage influenced the levels of CEA, CA 19-9, and TPA, but not those of TPS, while tumor grade influenced CEA and TPS, but not CA 72-4, TPA, and TPM. TPA was the most sensitive index in identifying early or well-differentiated colorectal cancers. The sensitivity was enhanced when this marker was determined in combination with CEA, in diagnosing both advanced and early colorectal tumors. Seventy-seven patients were followed up after therapy for at least 18 months. CEA was the most sensitive index of recurrence (58%); however, this sensitivity is too low to consider tumor markers useful in colorectal cancer follow-up.

Optimal follow-up in colorectal cancer patients: what tests and how often?

Patients' benefit from follow-up examinations after curative surgery for colorectal cancer is unproven in spite of numerous different programs' having been designed for that purpose. Unfortunately, no final results from prospective randomized studies have been published yet and no ideal marker for recurrent cancer is available to identify patients in whom new curative treatment may be possible. So far, screening for metachronous neoplasia with intervals of several years may influence survival, whereas benefit from detecting recurrent colorectal cancer may be claimed only by using historical or other inappropriate controls. The tradition of follow-up is expensive and prospective evidence for any cost benefit is needed to justify continuous use of our limited resources in this area of patient care.

Use of radiolabelled monoclonal antibodies in patients with primary and metastatic large bowel cancer

Accurate assessment of the extent of primary and metastatic large bowel cancer is critical to surgical decision making and to providing reliable prognostic information. This prospective study compared external gamma camera images and an intraoperative hand-held gamma detecting probe for detection of radiolabelled monoclonal antibody (B72.3) in 28 patients with primary and metastatic large bowel cancer. Fourteen patients received 0.2 to 20 mg (2 or 5 mCi) 111indium-labelled monoclonal antibody B72.3 followed by whole body imaging scan with an external gamma detector/camera on two occasions 24 h apart within 7 days after injection. Fourteen patients received 1.0 mg (2.0 mCi) 125iodine-B72.3 followed by intraoperative probe evaluation 2-3 weeks postinjection. Mean patient ages for the two groups were 60 years (range 28-75 years) and 63 years (range 43-77 years), respectively. Disease sites were primary in the large bowel in six patients and primary as well as metastatic in 22 patients. External scanning detected 111indium-B72.3 uptake in 1/5 primary lesions, 1/7 hepatic and 1/3 extrahepatic sites. The intraoperative gamma probe localized disease in 1/3 primary lesions, 7/11 hepatic and 3/3 extrahepatic sites. The intraoperative gamma probe had a sensitivity of 71% for detection of metastases compared with a 20% sensitivity using the external gamma scan method (P = 0.03). 125iodine-labelled B72.3 influenced the extent of the operative procedure in 4/14 (29%) patients; immunolocalization with external gamma detection did not alter the operative procedure in the 14 patients studied.(ABSTRACT TRUNCATED AT 250 WORDS)

Role of CEA, TPA, and Ca 19-9 in the early detection of localized and diffuse recurrent rectal cancer

Sixty-six consecutive patients who underwent curative resection for rectal cancer were studied prospectively to evaluate the roles of sequential carcinoembryonic antigen (CEA), tissue plasminogen activator (TPA), and carcinomatous antigen 19-9 (Ca 19-9) determinations in the early diagnosis of resectable recurrences. Thirty-three recurrences were detected between 6 and 42 months. CEA, TPA, and Ca 19-9 showed a sensitivity of 72.7 percent, 78.8 percent, and 60.1 percent, respectively, and a specificity of 60.6 percent, 60.6 percent, and 87.9 percent, respectively. In 23 cases the rise in the value of CEA and/or TPA and/or Ca 19-9 was the first sign of recurrences, and the diagnosis was established later by clinical methods. In this group, the lead time was two months for liver metastases and four months for disseminated metastases. As far as the relationship between localization of recurrence and marker level increase is concerned, of 16 hepatic metastases CEA, TPA, and Ca 19-9 showed a sensitivity of 94 percent (P less than 0.05), 69 percent, and 62 percent, respectively. Of six patients with local recurrences, CEA, TPA, and Ca 19-9 showed a sensitivity of 50 percent, 100 percent (P less than 0.05), and 83.3 percent, respectively. Of three patients with peritoneal carcinomatosis, CEA, TPA (P less than 0.05), and Ca 19-9 showed a sensitivity of 0 percent, 100 percent, and 0 percent, respectively. No significant differences were reported among the three markers according to multiple metastases and metachronous polyps. Fourteen patients (42.4 percent) underwent surgical treatment for recurrent disease, and eight of them (57 percent) showed a resectable disease, for a total resectability rate of 24.2 percent. The findings of our study indicate that a follow-up program based on CEA, TPA, and Ca 19-9 assays is related to an early diagnosis and a good resectability rate for both local and metastatic recurrences from rectal cancer.

Gastrointestinal cancer follow-up: the effectiveness of sequential CEA, TPA and Ca 19-9 evaluation in the early diagnosis of recurrences

One-hundred and seventy-four consecutive patients who underwent curative resection for gastric and colorectal cancer between 1983 and 1985 were studied prospectively to evaluate the roles of sequential carcinoembryonic antigen (CEA), tissue polypeptide antigen (TPA) and Ca 19-9 determinations and independent clinical examinations, in the early diagnosis of resectable recurrences. Sixty-six recurrences (33 from gastric and 33 from colorectal cancer) were detected between 6 and 42 months after primary surgery. In gastric cancer CEA, TPA and Ca 19-9 showed a sensitivity of 64%, 73% and 60% respectively and a specificity of 67%, 65% and 54% respectively. Nine patients (27%) underwent surgical treatment for recurrent disease, and four of these (44.4%) had resectable recurrence, for a total resectability rate of 12%. Of these four patients, three are still living after 12, 36 and 44 months respectively from re-operation without evidence of neoplastic disease. In one of these patients, re-operation was performed on the basis of the elevation of the three markers, without any other clinical sign of disease. This patient had a resectable solitary hepatic recurrence. In colorectal cancer. CEA, TPA and Ca 19-9 showed a sensitivity of 73%, 73% and 49% respectively, and a specificity of 77%, 87% and 97% respectively. Fourteen patients (42.4%) underwent surgical treatment for recurrent disease and eight of these (57%) showed resectable recurrence, for a total resectability rate of 24.2%. Six patients are still living after 9, 16, 21, 31, 41 and 53 months respectively from re-operation without evidence of neoplastic disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Serum carcinoembryonic antigen and DNA ploidy in colorectal carcinoma. A prospective study

We have analysed the relationship between carcinoembryonic antigen (CEA) and DNA ploidy prospectively in 130 colorectal carcinoma patients. CEA was elevated preoperatively significantly more often in patients with DNA-aneuploid tumours than in DNA-diploid or DNA-tetraploid tumours--that is, in 48% (36 of 75) of patients with aneuploid tumours, in 34% (14 of 41) of patients with diploid tumours, but only in 14% (2 of 14) of patients with tetraploid tumours (p less than 0.05). Aneuploid tumours had an elevated CEA level in 38% of stage A-B disease and in 61% of stage C-D disease. The elevated CEA values (greater than or equal to 5.0 micrograms/l) correlated with tumour stage in patients with aneuploid tumours but not in patients with diploid tumours. Whereas CEA is a suitable marker for aneuploid carcinomas, other more sensitive tumour markers should be sought for diploid and also for tetraploid tumours. If such markers are found, flow cytometry could provide the most important information in selecting individual follow-up programmes for colorectal cancer patients.