1. ASSESSMENT & SURGERY OF LIVER METASTASES
Janelle Brennan
St.Vincent’s Hospital

2. BACKGROUND 5 yr survival of unRx CRC mets <2%,
< 5% for non-operative Rx
Resection of colorectal mets can give 5 year survival figures between 25-40%
Resection is the only chance for long term survival
Only 7-10% patients with CRC liver mets will ultimately benefit from resection

3. CASE 1 69 y.o. male 18/12 ago had resection for Dukes C sigmoid ca
Treated with adjuvant chemotherapy
Routine follow up with oncologist
Normal CEA
CT Abdo/Pelvis

5. What segment is the lesion in?

6. What Ix would you perform?
Triple phase CT
PET scan – increased uptake in the left lobe
Colonoscopy – no other metachronous bowel tumours

7. GOALS OF ASSESSMENT 1. Detect hepatic metastases
2. Ensure no metachronous primary
3. Ensure no distant metastases
4. Ensure attempted curative resection is possible

8. Ix to detect mets Ultrasound CT (contrast enhanced, triple phase)
Available, inexpensive, distinguishes solid from cystic lesions
BUT operator dependent
Sensitivity ~94% of lesions > 2cm, but only ~56% sensitivity for lesions < 1cm
CT (contrast enhanced, triple phase)
Accuracy 80-93% for lesions >1cm, but only 68% for lesions <1cm

9. Ix to detect mets CTAP (CT scan arterial portography)
Selective catherization of splenic artey followed by bolus contrast & scanning during portal venous phase
Mets are supplied by hepatic artery, 80% normal liver supplied by portal vein
ADV – more sensitive for mets<10mm and allows more precise localization of tumour within hepatic segments
DISADV – invasive, false +ves from flow artefacts
MRI
Good at lesions <1cm
Ferumoxide enhanced

10. CT portography

12. Ix to exclude distant mets
PET
High uptake of 18-FDG in liver and tumour deposits
Sensitivity – 94%
ADV
Whole body assessment
Metabolising vs scar tissue
DISADV
Expensive, often unavailable

13. Ix to exclude distant mets
LAPAROSCOPY +/- LAP U/S
Allows peritoneal inspection
Assess extrahepatic disease and vessel invasion (U/S)
Assess liver parenchyma
May biospy normal liver
INTRAOPERATIVE U/S
Highly sensitive (~97%) & specific (~100%)
Good for lesions deep with liver & <10mm
Delineate anatomical landmarks
Additional liver mets in up to 33% of pts with lesions detected on preop imaging (BJS 1994; 81:1660-3)

14. Case 1 – should the lesion be biopsied preoperatively?NO
Difficult pathological analysis
Risk of seeding
Risk of complications e.g. bleeding

15. What is the definitive Mx?
Left lateral segmentectomy
SURGICAL STRATEGIES
Wedge excision vs segmental resection
Nomenclature of hepatectomy (Brisbane classification – 2000)

16. 12 month follow up
CEA – 95
CT chest/abdo/pelvis

18. Further Ix & Mx PET & Laparoscopy + U/S Right hepatectomy
No other intra- or extra-hepatic disease
Right hepatectomy

19. RE-RESECTION
~10-15% pts who undergo liver resection for CRC mets are potential candidates for reresection
Most hepatic recurrences develop in areas remote from the original resection site
Repeat hepatic resection gives comparable results to primary resection (operative mortality, disease-free survivial, overall survival)
More wedge resections than anatomic resections in 2nd hepatectomy
Pts who have a disease free interval of <1 year since their 1st hepatectomy  may benefit from period of observation to allow Ax of true extent of disease

20. CASE 2 65 y.o. female presents to LMO with vague upper abdo discomfort
Otherwise well
CT Abdomen

23. How would you Ix? Tumour markers
E.g. CEA, AFP
Routine bloods – FBE, U&E/Cr, LFTs, INR
Triple phase CT
CT chest/abdo/pelvis
Rigid sigmoidscopy – small lesion in rectum at 10cm, adenocarcinoma on biospy

24. Mx of synchronous met
At presentation, up to 25% of pts with CRC have synchronous distal mets
Principles:
Stage hepatic met for resectablity e.g. CT portography, MRI, PET
Stage primary tumour (Rx identical)
Assess general performance status
Hepatobiliary surgeon

25. Immediate vs delayed resection
Delaying resection for 3-6/12 may allow occult disease to become clinically detectable
BUT –
? Additional mets found at re-evaluation may represent new metastatic lesions
? Allows increased size of lesions  can become irresectable
Interval re-evaluation appears not to impair overall survival AND potentially 2/3 pts can be spared the mortality/morbidity of noncurative hepatic surgery
Lambert et al. Arch Surg

26. Delayed vs immediate resection
If met is small, peripherally located & easily removed
Negligible increase in morbidity/mortality at primary resection and saves 2nd laparotomy
Should avoid major hepatic resection
Added morbidity and mortality
Insufficient metastatic workup (if found at time of surgery)
Possibility of extensive revision of incision
Prognosis after resection is not dependent on time of detection of metastatic disease

27. Interval chemotherapy?
Chemotherapy can eradicate micrometastases so can be used in interval period
patients who remain technically resectable at re-evaluation but have disease progression on chemo - ?subgroup that does not benefit from resection
If respond to chemo  may become technically easier to resect

28. Case 3 45y.o. male 2 years post ULAR for T3N1 rectal cancer
Neoadjuvant chemo/XRT
Rising CEA over last 6 months
6  11  22
Restaged
No evidence of locoregional recurrence on MRI/PET
Multiple metastases in R lobe

29. ?Suitability for resection

30. Indications for Resection
All demonstrable tumour can be removed
No. of mets does not seem to be important
Resect as many as 7 hepatic colorectal mets without a decrease in survival
Moroz et al. ANZJS. Jan 2002
?Combine surgery with cryotherapy/RFA
Aim for margins of 10mm (but not absolute C/I)
No extrahepatic disease
Exceptions – Diaphragm, Lung
Positive hepatic nodes regarded same as other extrahepatic disease  rare to have long term survival even if LNs are resected
Rodgers & McCall. BJS. 2000

31. Contraindications for resection
Absolute
Not fit enough to tolerate GA/abnormal liver function
Residual liver function after resection would be inadequate (Aim for post op resection vol. ~ 35%)
Uncontrolled primary disease
Relative
Resection of hepatic met is not easily performed
E.g. Caudate lobe (Segment 1), invading IVC
Tumour invading portal vein confluence (limit curability)
Bilobar distribution of metastases

32. Is this resectable?

33. Large hepatic mets Neoadjuvant chemotherapy to downstage disease
Portal vein embolization to hypertrophy the small hepatic remant
Increase in remnant liver volume averages 12% of total liver
Abdalla et al. BJS. 2001
May sterilise periphery of large tumour
Used for pts with normal liver where anticipated liver remant vol. is <25% of total liver volume, pts with compromised liver function – Liver remnant volume <40%
Does not increase risks associated with major liver resection
Staged liver resections

34. Non colorectal hepatic mets
Potentially curative
Renal cell carcinoma, Adrenocortical ca, Wilm’s tumour
Neuroendocrine e.g. carcinoids,VIPoma
Even if can’t achieve curative resection  tumours are slow growing & excellent palliation of Sx
Remember in DDx – intrahepatic cholangiocarcinoma
No survival advantage
Breast, pancreatic, oesophageal, gynae
?sarcoma if feasible to remove all tumour from the liver BUT survival beyond 5yrs is rare