癌症新知：C型肝炎感染會加倍腎細胞癌風險

 

作者：Roxanne Nelson  出處：WebMD醫學新聞【24drs.com】April 8, 2010

    慢性C型肝炎（HCV）是肝硬化、肝衰竭、肝癌的主要成因之一，但是一項新的研究結果顯示，這可能也與腎細胞癌（RCC）有關。

　　密西根底特律Henry Ford醫院的研究者發現，在10年間，感染C型肝炎病患發生RCC的風險幾乎加倍。

　　這項研究線上發表於3月23日的癌症流行病學、生物標記與預防期刊上。

　　主要作者、Henry Ford醫院肝臟部門主任Stuart C. Gordon醫師表示，直到現在，僅有少數過去的病例報告顯示HCV與腎臟癌症增加有關。他向Medscape腫瘤學表示，但是這是第一篇以整合方式評估其間關聯的研究。

　　Gordon醫師解釋，他觀察到，在他的執業場所，感染HCV的RCC患者越來越多，因此，這項研究的結果相當令人興奮，且確認我們所懷疑以及在文獻上所看到的。

　　作者們表示，慢性HCV感染患者可能以肝臟外的併發症表現，例如冷凝球蛋白血症、血管炎、以及許多腎臟異常；感染也會造成非何杰金氏淋巴瘤與其他血液癌症風險上升。

　　Gordon醫師指出，腎絲球與腎小管結構已經分離出HCV病毒。C型肝炎是一種全身性疾病，且其影響並不侷限於肝臟，它不只造成肝臟疾病，也可能會導致腎臟疾病的發生。

　　【RCC的獨立危險因子】

　　這項新發現來自於一項世代研究，以Henry Ford醫院一個大型、整合的、包括不同人種的資料庫進行研究。這項研究收納67,063位在1997年到2006年之間接受HCV檢驗的患者，這些患者被追蹤是否發生RCC，直到2008年4月。

　　在這個族群中，3057位（4.6%）病患為HCV陽性，且比血清陰性患者年齡大（52歲相較於48歲；P<0.001）。相較於未感染患者，罹患HCV患者比較容易罹患腎臟疾病（14.5%相較於10.4%；P<0.001），且一如預期，他們發生肝癌的風險也比較高（每1000位感染HCV患者27.5件，相較於每1000位未感染HCV患者的1.4件）。

　　HCV陽性病患有0.6%被診斷罹患RCC（3057位中有17位），HCV陰性患者的則是0.3%（64,006位中有177位）。HCV陽性患者被診斷罹患RCC的平均年齡顯著較低（54歲相較於63歲；P<0.001）。HCV患者罹患RCC的單變項危險比值為2.20（95%信賴區間[CI]為1.32-3.67；P=0.0025）。在多變項模式中，納入危險因子，包括年齡、種族、性別與慢性腎臟疾病，HCV患者整體發生RCC危險比值為1.77（95% CI為1.05-2.98；P=0.0313）。

　　Gordon醫師指出，腎臟癌症是相當罕見的，且目前要建議HCV陽性患者進行更多整合篩檢仍嫌太早。然而，臨床醫師應該對其間的關係提高警覺，同時，罹患RCC患者必須要仔細地接受HCV感染篩檢。

　　作者們的結論是，需要更多的研究來確認這些發現，以及探索癌症生成的潛在機轉。

　　沒有外在機構或是贊助者資助這項研究。研究者們表示沒有相關資金上的往來。

 

Hepatitis C Infection Doubles Risk for Renal Cell Carcinoma

By Roxanne Nelson

Medscape Medical News

April 8, 2010 — Chronic hepatitis?C virus (HCV) is a major cause of cirrhosis, liver failure, and hepatocellular carcinoma, but a new study suggests that it is also associated with a higher incidence of renal cell carcinoma (RCC).

Researchers at Henry Ford Hospital in Detroit, Michigan, found that during a 10-year period, patients infected with hepatitis?C had nearly double the risk of developing RCC.

The study was published online March?23 in Cancer Epidemiology, Biomarkers & Prevention.

Until now, there have only been anecdotal reports that suggested an association between HCV and an increased risk for kidney cancer, said lead author Stuart C. Gordon, MD, director of hepatology at Henry Ford Hospital. "But this is the first report to evaluate the association in a comprehensive manner," he told Medscape Oncology.

 

Dr. Gordon explained that he has observed increased rates of RCC in patients infected with HCV in his own practice. Thus, the results of this study were "exciting and reassuring and validated what we had suspected and what we had seen in the literature," he said.

The authors note that patients with chronic HCV infection can manifest extrahepatic complications, such as cryoglobulinemia, vasculitis, and various renal disorders. Infection also confers an increased risk for non-Hodgkin's lymphoma and other hematopoietic malignancies.

HCV has been isolated in kidney glomerular and tubular structures, Dr. Gordon pointed out. "Hepatitis?C is a systemic disease, and its impact is not restricted to the liver," he said. "Independent of liver disease, it can also cause kidney disease."

Independent Risk Factor for RCC

The new findings come from a cohort study of administrative data from the large, integrated, and ethnically diverse Henry Ford Hospital. The study consisted of 67,063 patients who were tested for HCV between 1997 and 2006, and who were followed for the development of RCC until April 2008.

Of this population, 3057 (4.6%) patients were HCV-positive, and were older than those who were seronegative (52 vs 48 years; P?< .001). Patients with HCV were more likely to have kidney disease than uninfected patients (14.5% vs 10.4%; P?< .001) and, as expected, their risk of developing hepatocellular carcinoma was much higher (27.5 of 1000 HCV-positive patients vs 1.4 of 1000 HCV-negative patients).

A diagnosis of RCC was made in 0.6% (17 of 3057) of HCV-positive patients and in 0.3% (177 of 64,006) of HCV-negative patients. The mean age at diagnosis was much younger in those who were HCV-positive (54 vs 63; P?< .001). The univariate hazard ratio for RCC among HCV patients was 2.20 (95% confidence interval [CI], 1.32?- 3.67; P?= .0025). In a multivariate model that included risk factors such as age, race, sex, and chronic kidney disease, the overall hazard ratio for RCC among HCV patients was 1.77 (95% CI, 1.05?- 2.98; P?= .0313).

Kidney cancer is relatively rare, explained Dr. Gordon, and it is premature to recommend more comprehensive screening of HCV-positive patients. "However, physicians should be aware of this relationship," he said, "and patients with RCC may need to be more carefully screened for HCV infection."

"Additional studies are required to confirm these findings and to explore potential mechanisms of oncogenesis," the authors conclude.

No outside agencies or sponsors provided funding for this study. The researchers have disclosed no relevant financial relationships.

Cancer Epidemiol Biomarkers Prev. Published online March 23, 2010.