LETTERS

Lymph Node Evaluation as aPredictor of Survival after Resectionfor Colorectal Cancer

Giuseppe Pappalardo, MD, FACS

Aldo Nunziale, MD

Rome, Italy

We read with great interest the article by Jan H Wong andcolleagues, “Lymph node counts as an indicator of qualityat the hospital level in colorectal surgery.”1 If the number oflymph nodes evaluated after surgical resection of colorectalcancer (CRC) has a significant impact on survival, it rep-resents an item frequently discussed in the last decades.There was no statistically significant difference in disease-specific survival for N1 or N2 patients between 3 groupswith median number of nodes examined, respectively, of 4,8, 10 in Region 5 of the California Cancer Registry. Thesedata contradict other reports, which demonstrated a dra-matic impact of lymph node harvest on survival for bothN1 and N2 positive disease.2 These findings in stage IIIdisease could show an impact that transcends simple un-derstaging and undertreatment in N negative patients withless than 12 examined nodes. At the present time, there isgreat confusion about lymph node counts as a predictor ofsurvival and quality at the hospital level in CRC patients.Many factors can contribute to the difficulties in evaluatingdata regarding the relationships between lymph nodes andsurvival: the extent of lymphadenectomy, the number ofnodes examined, the significance and the role of microme-tastases, the ratio of positive to total nodes harvested, etc.We believe that one additional factor could be underesti-mated: the lack of standardization of specimen handlingtechniques. Should only palpable nodes be evaluated? Arefat-clearing techniques mandatory or optional? The lack ofthis standardization creates a bias that makes pathologicexamination operator dependent. In other words, the samespecimen can give different results on lymph nodes re-moved. Any effort to obtain a standardized pathologic ex-amination should be made to improve results and analysisof quality in the treatment of CRC patients.

REFERENCES

1. Wong JH, Lum SS, Morgan JW. Lymph node counts as an indi-cator of quality at the hospital level in colorectal surgery. J Am

Coll Surg 2011;213:226–230.

125© 2012 by the American College of SurgeonsPublished by Elsevier Inc.

2. Le Voyer TE, Sigurdson ER, Hanlon AL, et al. Colon cancersurvival is associated with increasing number of lymph nodesanalyzed: A secondary survey of intergroup trial INT-0089. J ClinOncol 2003;21:2912–2919.

Disclosure Information: Nothing to disclose.

Reply

Jan H Wong, MD, FACS

Greenville, NC

Sharon S Lum, MD, FACS

John W Morgan, DRPH

Loma Linda, CA

We thank Drs Pappalardo and Nunziale for their review ofour article on the potential use of lymph node counts as anindicator of quality at the hospital level. In their letter, theauthors reinforce the association of lymph node counts andsurvival in patients with colorectal cancer, which we and oth-ers have previously demonstrated. Drs Pappalardo and Nun-ziale suggest that our results contrast with those from theseearlier reports. It should be re-emphasized that our intentwas not to re-examine whether lymph node counts affectsurvival in patients with N0, N1, or N2 disease, but rather,to examine whether the median number of nodes exam-ined at the hospital level was associated with improvedstaging and outcomes in patients with colorectal cancercared for within that hospital, so therefore might be a usefulquality indicator.

Drs Pappalardo and Nunziale raise a valid concern thatthe lack of standardized handling of the specimen mightcontribute to variability in the number of nodes examinedbetween hospitals and might obscure any association be-tween the number of nodes examined at the hospital leveland outcomes. It is reasonable to presume that variabilityexists not only in the pathologic handling of the specimenbut in the conduct of the surgical resection. Data used inour study were extracted from R5 CCR, a population-based cancer registry serving a large and diverse segment ofthe California population. Unlike a single pathology ser-vice, the population-based registry findings used in ouranalyses included data from 33 hospitals that were reportedby as many as 100 different pathologists during the 10 years

assessed. Use of specialized techniques for discovery of

ISSN 1072-7515/12/$36.00doi:10.1016/j.jamcollsurg.2011.09.013