The impact of knowledge transfer on the detection of venous invasion in colorectal cancer.

Venous invasion (VI) is an independent predictor of hematogenous metastasis and mortality in colorectal cancer (CRC) yet remains widely underreported. Its detection may require recognition of subtle morphologic clues, which at times are only unmasked with an elastin stain. This study evaluates the impact of a knowledge transfer initiative (KTI) on VI detection in a "real-world" pathology practice setting. Following participation in an interobserver variability study of VI detection (Kirsch et al, 2013), 12 participants received educational materials highlighting key issues in VI detection. Eighteen months later, participants were invited to submit pathology reports from all CRC resections signed out 18 months prior to and 18 months following the KTI (n = 266 and n = 244, respectively). Nine pathologists participated. Reports were reviewed for VI and other established prognostic factors. Numbers of elastin stains and tumor-containing blocks were also recorded. Comparative analyses were adjusted for baseline differences in tumor, lymph node, and metastasis stage; tumor location; use of neoadjuvant therapy; and number of tumor-containing blocks. VI detection increased significantly post-KTI versus pre-KTI (39.3% versus 18.4%, adjusted odds ratio [OR] 2.86 [1.91-4.28], P < .001). Increased VI detection post-KTI was observed in both stage II (31.8% versus 12.5%, adjusted OR 3.27 [1.45-7.42], P = .004) and stage III CRC (62.4% versus 28.2%, adjusted OR 4.23 [2.37-7.55], P < .001). All pathologists demonstrated increased VI detection post-KTI. Use of elastin stains was significantly higher post-KTI versus pre-KTI (61.5% versus 5.3% of cases respectively, P < .001). This study demonstrates the effectiveness of knowledge transfer in increasing VI detection in routine pathology practice.

Interobserver variability in assessing dysplasia and architecture in colorectal adenomas: a multicentre Canadian study.

AIMS: Following the introduction of colorectal cancer screening programmes throughout Canada, it became necessary to standardise the diagnosis of colorectal adenomas. Canadian guidelines for standardised reporting of adenomas were developed in 2011. The aims of the present study were (a) to assess interobserver variability in the classification of dysplasia and architecture in adenomas and (b) to determine if interobserver variability could be improved by the adoption of criteria specified in the national guidelines. METHODS: An a priori power analysis was used to determine an adequate number of cases and participants. Twelve pathologists independently classified 40 whole-slide images of adenomas according to architecture and dysplasia grade. Following a wash-out period, participants were provided with the national guidelines and asked to reclassify the study set. RESULTS: At baseline, there was moderate interobserver agreement for architecture (K=0.4700; 95% CI 0.4427 to 0.4972) and dysplasia grade (K=0.5680; 95% CI 0.5299 to 0.6062). Following distribution of the guidelines, there was improved interobserver agreement in assessing architecture (K=0.5403; 95% CI 0.5133 to 0.5674)). For dysplasia grade, overall interobserver agreement remained moderate but decreased significantly (K=0.4833; 95% CI 0.4452 to 0.5215). Half of the cases contained high-grade dysplasia (HGD). Two pathologists diagnosed HGD in ≥75% of cases. CONCLUSIONS: The improvement in interobserver agreement in classifying adenoma architecture suggests that national guidelines can be useful in disseminating knowledge, however, the variability in the diagnosis of HGD, even following guideline review suggests the need for ongoing knowledge-transfer exercises.

Venous invasion in colorectal cancer: impact of an elastin stain on detection and interobserver agreement among gastrointestinal and nongastrointestinal pathologists.

Venous invasion (VI) is an independent prognostic indicator in colorectal cancer and may prompt consideration for adjuvant chemotherapy in patients with stage II tumors. Recent evidence suggests that VI is underreported in colorectal cancer and that detection may be enhanced by an elastin stain. This study aimed (1) to determine the impact of an elastin stain on VI detection and on interobserver agreement between gastrointestinal (GI) and non-GI pathologists, and (2) to identify factors associated with increased VI detection. Forty hematoxylin and eosin (H&E)-stained slides were circulated to 6 GI and 6 non-GI pathologists who independently assessed the VI status as positive, negative, or equivocal. Six weeks later, 40 corresponding Movat-stained slides were recirculated together with the original H&E slides and reassessed for VI status. Detection of VI was >2-fold higher with a Movat stain compared with an H&E stain alone (46.4% vs. 19.6%, P=0.001). GI pathologists detected VI more frequently than non-GI pathologists on both H&E (30.0% vs. 9.2%, P=0.029) and Movat (58.3% vs. 34.6%, P=0.018) stains. There was higher interobserver agreement in the case of a Movat stain, particularly for extramural VI (H&E: κ=0.23 vs. Movat: κ=0.41). A poststudy survey indicated that GI pathologists and non-GI pathologists applied similar diagnostic criteria but that GI pathologists more frequently applied "orphan arteriole" and "protruding tongue" signs as diagnostic clues to VI. This study confirms that VI is underdetected on H&E and highlights the role of elastin staining in improving VI detection and interobserver agreement. Strategies to improve VI detection are warranted.

Complex Collagenous Spherulosis of the Breast Presenting as a Palpable Mass: A Case Report with Immunohistochemical and Ultrastructural Studies.

Collagenous spherulosis is a rare, benign breast lesion occuring in less than 1% of benign breast biopsies. All previously reported cases have been discovered as incidental microscopic findings in association with a range of benign to malignant processes. The authors report the first case of collagenous spherulosis presenting as a palpable mass. Immunohistochemistry and electron microscopy performed on this lesion demonstrated the presence of two cell types: epithelial cells and myoepithelial cells with associated basement membranelike material. Collagenous spherulosis may mimic adenoid cystic carcinoma since the epithelial proliferation and spherule formation in collagenous spherulosis closely resembles the changes in adenoid cystic carcinoma. However, adenoid cystic carcinoma is an invasive lesion that is almost always palpable, while collagenous spherulosis is almost always an incidental microscopic finding. Our case illustrates that collagenous spherulosis can also result in a palpable mass, thus palpability of the lesion cannot be used to differentiate these conditions.