To Count and How to Count, That Is the Question

Abstract

Optimal cancer staging requires retrieval of a minimal number of nodes. However, variability among pathologists in counting on a slide has not been studied. To study the differences in node counting among pathologists, 10 pathologists counted nodes on 15 slides on 2 occasions. They also opined on whether selected "structures" represented countable nodes. There was no slide on which all pathologists agreed on all occasions. The greatest variability was on slides on which the number of nodes exceeded 8. There was disagreement on the size of the smallest countable node, on how to count 2 closely related structures, and when the gross disagreed with the microscopic finding. With a mean count of 5.7 nodes per slide, the 95% confidence interval was +/- 2.6, which could be clinically significant when the count approaches the set minimum. Uniform criteria are necessary to allow for meaningful comparisons between studies on minimal nodal counts for cancer lymphadenectomies.

Lymph Node Yield in Colon Cancer: Individuals Can Make the Difference

“…Previous studies have pointed out that LNY varies between pathological laboratories, hospitals and even over geographic location [24,33,36,37]. These findings suggest that the adequacy of lymph node retrieval may be suboptimal in some hospitals but also that it could improve with appropriate education and standardised surgical and pathological techniques.…”

“…After visualisation and palpation, fat-clearing procedures can be used to double the number of lymph nodes found in the gross room, although they are time- and labour-consuming procedures [24]. Likewise, other methods, such as entire submission and advanced fixation techniques, have been shown to increase LNY but are considered too costly for routine use [25,26,27].…”

Inter- and Intra-Operator Variability in the Reading of Indirect Immunofluorescence Assays for the Serological Diagnosis of Scrub Typhus and Murine Typhus

“…Similar subjectivity has been noted in other studies requiring the interpretations of individual operators. In a study of inter-observer and intra-observer variability among pathologists in lymph node assessments, 15 slides wereassessed by 10 pathologists, and significant disagreement on the size of the smallest countable node was noted 11. An analysis of thin-preparation Papanicolaou tests among 19 cytotechnologists from three different laboratories also showed significant variability 6…”

Pelvic lymph node dissection in the context of radical cystectomy: a thorough insight into the connection between patient, surgeon, pathologist and treating institution

“…Moreover, the more accurate the pathologist’s report on the embedding of nodes, the easier the counting of LNs under the microscope ( Figure 1 ). 43 Fourth, and a rarely reported factor, the amount of tissue that is embedded for microscopic examination affects LN yield; embedding the entire specimen, for example, increases the number of nodes identified. 42 According to personal, unpublished data (2009), approximately two additional nodes are found per packet in the remaining, not routinely embedded lymphadenectomy tissue.…”

“…Fifth, although the histological criteria defining LNs are clearly established, the determination of a LN in a microscopic slide not only depends on the sectional plane through the LN, but also varies between pathological institutes and pathologists. 43 Parkash et al 43 evaluated LN counts on slide scans performed by ten pathologists, each pathologist receiving the same series of slides for review. They noted considerable interobserver and intra-observer variability, which was particularly dependent on the macroscopic description of the slide given by the study coordinator.…”