Primary HCC is a major cancer related to HBV viral infection in Asian countries, including Japan. Recently, the primary liver cancers are successfully treated by surgical resection including liver transplantation and non-surgical locoregional therapy. Although not frequently, extrahepatic spread to the lung, so called lung metastasis from liver cancer is a dilemma, because it may be believed that diseases are very advanced and too late in being adequately treated. It is partly true that most of the patients with lung metastasis from liver cancer did not survive for more than 1 year. However, surgical resection has gained the benefit of better survival in a selected group. It is not well understood regarding when and how to undergo surgery for lung metastasis. Although small in numbers, successful results after collaborative treatments for lung metastasis from liver cancers were achieved.
A research article to be published on October 7, 2008 in the World Journal of Gastroenterology addresses this question. The research team led by Professor. Moon from Kangnam St. Mary Hospital, the Catholic University of Korea, consists of thoracic surgeons, liver physicians, and liver surgeons. For 8 years, the researchers studied 23 patients with liver cancer and concurrent or subsequent lung lesions, who underwent lung surgery with collaborative guidelines. After lung surgery, the treatment plans had to be changed according to pathology-matched basis. With true lung metastasis, 16 patients were observed (the longest one being more than 8 years), and were analyzed for survival and clinical prognostic factors.
The 1- and 5-year survival rates after the lung surgery were 56% and 26%, respectively, most of whom otherwise would die within one year without lung surgery. Although statistical power is weak due to small numbers, new prognostic factor was identified: patients who underwent liver transplantation and developed lung metastasis, survived longer after lung surgery. This message suggests that liver transplantation is the standard for treatment of liver cancer and guarantees longer survival, even in case of lung metastasis.
Looking into long-term survivors for more than one year, proper control or treatment for primary liver cancers should be prerequisite for long-term survival. Hepatic cancer recurrence or hepatic dysfunction is the major cause of deaths. Their team approach helped the patients with lung metastasis survive longer rather than waiting for death. Minimally invasive or thoracoscopic surgery is another reason why the patients and physicians adopted lung surgery. Another concern was brain metastasis, which was fatal and detected before being dying. The researchers strongly recommended MRI for subclinical brain metastasis, which can be adequately treated by surgery or radiation surgery.
As indicated by peer reviewer, this clinical research failed to identify the promising clinical prognostic factors increasing survival for the patients with liver cancer and lung metastasis, but it is needed to identify significant prognostic factors in collaboration with multi-institutions. More importantly, research on these factors may provide adequate treatment guidelines for patients and oncologic specialists. Last but not least, clinical research based on well-designed treatment plan can advocate the proper treatment modality.