Management of Primary and Metastatic Tumors to the Liver

This comprehensive report summarizes the current management ofprimary liver cancer and of metastatic colorectal cancer in theliver. Numerous tests to help define the location and stage ofdisease have been evaluated. It now appears that spiral CT witharterial portography is superior to other nonoperative methodsin evaluating liver tumors. Immunoscintography using monoclonalantibodies is currently under development and appears to be ofpotential great value. Subclinical, micrometastatic disease isthe bane of all efforts at surgical control of cancer. An abilityto detect this would have far-reaching consequences. Completeevaluation of patients with these diseases must include a medicalevaluation, including liver function tests and a chest CT. Particularattention must also be paid to cardiac, pulmonary, and renal function.

It is worth noting that exploratory laparotomy need not have theadverse effects described by the authors. Rarely have I seen patientsharmed by a simple laparotomy. An incisional biopsy can spreadcancer, which appears as accelerated tumor growth in the occasionalpatient with advanced disease and is best avoided. Usually, incurablepatients are on a downhill course and the operation is merelyan incidental event.

The use of intraoperative ultrasound is reported to have changedmanagement in 15% to 49% of patients. Bimanual examination ofa mobilized liver by an experienced liver surgeon is very accurate.In such instances, intraoperative ultrasound (IOUS) usually findsadditional lesions that are best undetected, ie, small hemangiomasor harmatomas. Intraoperative ultrasound is useful in locatingintrahepatic vascular structures and perhaps in detecting diseaseby less experienced surgeons.

The beneficial effect of porta hepatis and celiac axis lymph nodedissection combined with hepatic resection has had limited attention.I know of no systematic study of this procedure. The operationis technically difficult. Piecemeal removal of lymph nodes isa futile gesture, and fracturing any positive lymph node wouldspread cancer. Careful preparation in cadaveric dissections byparticipating surgeons would be a prerequisite to adequate evaluationof this procedure.

Adjuvant chemotherapy given either by hepatic arterial infusionor systemically should be used only in controlled studies whereits as yet undetermined benefit can be evaluated.

It is helpful to remember that highly selected patients with metastaticcolorectal cancer to the liver and lung can be surgically salvagedoccasionally [1].

Contrary to the authors' conclusion, post-resection follow-upCT scans at 6-month intervals, along with the appropriate carcinoembryonicantigen (CEA) or alpha-fetoprotein estimation every 2 months and,if metastatic colorectal cancer, annual colonoscopy, have provendesirable and practical in my experience. Surgical removal orfreezing of any recurrent disease may be possible. Chemotherapyshould probably await symptomatic colorectal recurrence in orderto obtain the longest possible longevity benefit. The use of currentchemotherapy in patients with recurrent hepatoma merely make theremaining life span more miserable and possibly shorter.

Transplantation Useful for Highly Selected Patients Only

Liver transplantation appears useful for highly selected patientswith primary hepatomas. Although some studies appear to demonstratethe superiority of this procedure for hepatoma in general, surgicalresection with adequate margins is a safer and more practicaloption. Removing more nonmalignant liver does not improve curerates. The risks of multifocal disease are real, but may not appearor may become manifest only many years after the initial operation,when it may be handled again by resection, cryosurgery, or localinjection. Multifocal primary cancer also may be accompanied bypreviously occult metastatic disease.

Early and more recent experiences with liver transplantation formetastatic cancer have consistently shown its utter futility.Hopefully, this lesson will not have to be relearned in the future.

Surgical resection of primary and metastatic liver cancer is fairlywell defined. The development of adjuvant therapies to deal withdisease beyond surgical boundaries and therapies directed at inoperablecancer continues to pose challenges. The astonishingly good resultsachieved by alcohol injection and cryosurgery are very encouraging.The true place of these technologies vs standard resection remainsto be determined, and should be vigorously investigated.

Preliminary results from the extensive vaccination program againsthepatitis carried out in Asia and Africa should become evidentsoon. These efforts, combined with education about aflatoxin exposure,offer hope for a marked reduction in primary liver cancer on thosecontinents. Some decrease in liver cancer may become evident inthis country, but there remain a large number of hepatomas withno known etiologic factors.

The conflicting reports about chemoembolization may relate totechnique, the disease stage of treated patients, and the functionalreserve of nonmalignant hepatic parenchyma. Cirrhosis and hepatomaare predominantly secondary to hepatitis C infection in Japanand, to some extent, in other parts of Asia. Functional damageof hepatic cells is much less than for comparable degrees of hepatitisB or alcoholic cirrhosis.

Hepatic artery infusion chemotherapy seems to provide worthwhilepalliation, but it only marginally prolongs the life of patientswith colorectal carcinoma. Intra-arterial chemotherapy has beencompared with systemic chemotherapy, which may itself adverselyaffect patients' health, appetite, and resistance. At best, thesurvival advantage is measured in months, which seems an inadequatereward for the time, expense, discomfort, and toxicity of treatment.

Finally, it cannot be overemphasized that patients with primaryor secondary liver cancer should be treated at medical centersby experienced liver surgeons. The complexity of liver surgeryand the good therapeutic results achieved at these centers withlow mortality are the bases for this plea. The occasional liversurgeon is a dangerous person who cannot do justice to patientswith liver tumors.

References:

1. Smith W, Burt ME, Fortner JG: Resection of hepatic and pulmonarymetastasis from colorectal cancer. J Surg Oncol 1:399-404, 1992.