Fong Clinical Risk Score for Colorectal Cancer Recurrence

Why Use

Helps predict survival after resection of hepatic metastases of colorectal cancer. Aids in timing of surgical intervention. Provides guidance in adjuvant therapy. Aids in counseling patients to provide expected 5-year survival and median months of survival. Can aid in planning postoperative surveillance imaging. Can be used to compare patients from different institutions and studies.

When to Use

Patients with hepatic metastases from colorectal cancer without evidence of extrahepatic disease. Other Potential Use Cases Early operation runs the risk of missing smaller tumors when liver mets are small, while late operation runs the risk of progression in known metastases. The Fong Score allows risk stratification to help determine timing of surgical intervention as well as potential neoadjuvant/adjuvant therapy. The Fong Score can also help determine ideal candidates for novel imaging modalities for detecting occult disease ( F-FDG whole-body positron emission topography (PET) scanning, radioimmunoimaging, etc) ( Schüssler-Fiorenza 2004 ).

Formula

Pearls / Pitfalls

The Fong Clinical Risk Score for Colorectal Cancer Recurrence assigns colorectal cancer patients with liver metastasis a score of 0-5 based on 5 independent preoperative risk factors to estimate 5-year survival and median months of survival. Higher scores correlate with lower survival. Points to Keep in Mind The scoring system is designed to aid in timing of surgical intervention and provide guidance in adjuvant therapy, NOT necessarily to determine surgical candidacy. Even in patients with high scores (4-5), there is clear survival benefit from surgical intervention. Positive surgical margin is a significant independent risk factor for survival but was not included in the scoring system due to its inability to use in preoperative patient selection. All patients with >1 tumor were given a score of 1. However, with advancement in hepatic surgery, resection of up to four hepatic metastases is common, and there is even data that patients with up to 7 liver lesions can have a significant survival benefit from surgical resection ( Moroz 2002 ). Relative risks for the five criteria vary somewhat, but each is given a score of 1. Data shows that long-term outcome closely correlates with the current scoring system.

Management

From Khatri 2005 : Conventional indications Modern aggressive approach <4 metastases, unilobar disease No limits. Multiple/bilobar metastases acceptable, using neoadjuvant chemotherapy, staged resection, and resection/local ablative therapy. Size <5 cm No limits. No extrahepatic disease Pulmonary metastases can be resected. Resection margin >1 cm Resection margin <1 cm managed with ablative treatment of narrow margin (cryosurgery or radiofrequency ablation). Adequate remnant liver parenchyma Preoperative portal vein embolization to increase liver remnant volume. Resection of all macroscopic disease NED can be achieved with combination of resection and local ablative therapy. No metachronous liver metastases Synchronous and metachronous metastases acceptable. Absence of vena cava and hepatic vein confluence invasion No limits. Caval/hepatic vein resection with reconstruction can be performed. Absence of hepatic pedicle lymph node metastases In absence of celiac axis metastases, hepatic pedicle lymph node metastases may be resected for improved 3-year survival.

Critical Actions

About 1/3 of 5-year survivors ultimately die from their disease, and it is not yet certain whether the Fong Score accurately predicts survival beyond five years. Therefore, continued surveillance is currently recommended for patients after five years even if they are considered “low risk.” With continued advances in surgery, re-resection of hepatic metastases is proven to be still low risk while conferring a survival benefit, and therefore should be considered.

Advice

Patients with Fong Score 0-2 are considered “low risk” and may proceed with surgical intervention. Patients with Fong Score 3-5 are considered “high risk” and may benefit from close surveillance if surgery is deemed unacceptably high risk, additional preoperative workup/treatment before surgery, or additional postoperative treatment.

More Information

Variables: Nodal status of primary. Disease-free interval from the primary to discovery of the liver metastases of <12 months. Number of tumors >1. Preoperative CEA level >200 ng/mL. Size of the largest tumor >5 cm. Survival (%) Score 1-year 2-year 3-year 4-year 5-year 0 93 79 72 60 60 1 91 76 66 54 44 2 89 73 60 51 40 3 86 67 42 25 20 4 70 45 38 29 25 5 71 45 27 14 14