Aims: Digital pathology (DP) offers advantages over glass slide microscopy (GS), but data demonstrating a statistically valid equivalent (i.e. non-inferior) performance of DP against GS are required to permit its use in diagnosis. The aim of this study is to provide evidence of non-inferiority. Methods and results: Seventeen pathologists rereported 3017 cases by DP. Of these, 1009 were re-reported by the same pathologist, and 2008 by a different pathologist. Re-examination of 10 138 scanned slides (2.22 terabytes) produced 72 variances between GS and DP reports, including 21 clinically significant variances. Ground truth lay with GS in 12 cases and with DP in nine cases. These results are within the 95% confidence interval for existing intraobserver and interobserver variability, proving that DP is non-inferior to GS. In three cases, the digital platform was deemed to be responsible for the variance, including a gastric biopsy, where Helicobacter pylori only became visible on slides scanned at the 960 setting, and a bronchial biopsy and penile biopsy, where dysplasia was reported on DP but was not present on GS. Conclusions: This is one of the largest studies proving that DP is equivalent to GS for the diagnosis of histopathology specimens. Error rates are similar in both platforms, although some problems e.g. detection of bacteria, are predictable.

Adenocarcinomas exhibiting gastric differentiation represent a recently described and uncommon subtype of non-human papillomavirus (HPV) related cervical adenocarcinoma. They comprise a spectrum from a well differentiated variant (adenoma malignum/mucinous variant of minimal deviation adenocarcinoma) to a more poorly overtly malignant form, generally referred to as gastric-type adenocarcinoma. Rarely, such tumours have also been described as primary vaginal neoplasms. Gastric-type adenocarcinomas exhibit considerable morphological overlap with adenocarcinomas originating outside the female genital tract, especially mucinous adenocarcinomas arising in the pancreas and biliary tract. Moreover they often metastasize to unusual sites, such as the ovary and peritoneum/omentum, where they can be mistaken for metastatic adenocarcinomas from other, non-gynaecological sites. There is little information regarding the immunophenotype of gastric-type adenocarcinomas and knowledge of this is important to aid in the distinction from other adenocarcinomas. In this study, we undertook a detailed immunohistochemical analysis of a large series of cervical (n=45) and vaginal (n=2) gastric-type adenocarcinomas. Markers included were CK7, CK20, CDX2, CEA, CA125, CA19.9, p16, ER, PR, MUC6, PAX8, PAX2, p53, hepatocyte nuclear factor 1 beta (HNF1β), carbonic anhydrase IX (CAIX), HER2 and MMR proteins. All markers were classified as negative, focal (<50% of tumour cells positive) or diffuse (≥50% tumour cells positive) except for p53 (classified as “wild-type” or “mutation-type”), HER2 (scored using the College of American Pathologists guidelines for gastric carcinomas) and MMR proteins (categorised as retained or lost). There was positive staining with CK7 (47/47 – 45 diffuse, 2 focal), MUC6 (17/21 – 6 diffuse, 11 focal), CEA (25/31 – 12 diffuse, 13 focal), CAIX (20/24 – 8 diffuse, 12 focal), PAX8 (32/47 – 20 diffuse, 12 focal), CA125 (36/45 – 5 diffuse, 31 focal), CA19.9 (11/11 – 8 diffuse, 3 focal), HNF1β (13/14 – 12 diffuse, 1 focal), CDX2 (24/47 – 4 diffuse, 20 focal), CK20 (23/47 – 6 diffuse, 17 focal) and p16 (18/47 – 4 diffuse, 14 focal). Most cases were negative with ER (29/31), PR (10/11), PAX2 (18/19) and HER2 (25/26). p53 showed “wild-type” and ”mutation-type” staining in 27/46 and 19/46 cases respectively. MMR protein expression was retained in 19/20 cases with loss of MSH6 staining in one patient with Lynch syndrome. Molecular studies for HPV were undertaken in two tumours which exhibited diffuse” block-type” immunoreactivity with p16 and both were negative. This is the first detailed immunohistochemical study of a large series of gastric-type adenocarcinomas of the lower female genital tract. Our results indicate immunophenotypic overlap with pancreaticobiliary adenocarcinomas but suggest that PAX8 immunoreactivity may be especially useful in distinguishing gastric-type adenocarcinomas from pancreaticobiliary and other non-gynaecological adenocarcinomas which are usually negative. Diffuse “block-type”p16 immunoreactivity ...

The commonest mode of presentation of retinoblastoma in Nepal is proptosis. Presence of proptosis with orbital extension is associated with optic nerve cut end infiltration by the tumour. The diagnosis or presentation of retinoblastoma in Nepal is delayed and there is tremendous scope for improvement in its management.

Aims: To evaluate the diagnostic value of bone marrow aspirates, trephine biopsies (BMB), and flow cytometry (FC) in the assessment of bone marrow infiltration in chronic lymphoid disorders. Methods: Investigations were carried out in 110 diagnostic and follow up specimens from B cell disorders, namely: chronic lymphocytic leukaemia (CLL; 65), non-Hodgkin's lymphoma (NHL; 39), and hairy cell leukaemia (HCL; 6). A selected panel of monoclonal antibodies was used both for FC and immunohistochemistry. Results: In CLL there was agreement between the three investigations in 71% of samples and in 88% when only FC and BMB were compared. In nine of 65 samples, FC and BMB were positive, although the aspirate was reported as negative. Four BMB negative samples had minimal residual disease (MRD) detected by FC, whereas two samples were positive both on BMB and aspirate but showed no evidence of disease on FC. In NHL, there was agreement between the three investigations in 22 of 39 cases, and in 27 of 39 cases there was agreement between FC and BMB. In eight of 39 NHL cases, FC was negative but the BMB was either positive (five) or uncertain (three), whereas in three of 39, FC was positive but BMB was either negative (one) or uncertain (two). In three of five uncertain BMB, no clonal population was detected by the polymerase chain reaction, whereas in the remaining two cases the nodular aggregates disappeared on further sectioning. Conclusions: Both BMB and FC are better than bone marrow aspirates for the detection of infiltration in B cell disorders. FC might be slightly more sensitive than BMB to detect MRD in CLL, whereas BMB may be slightly better than FC in NHL.

No abstract

This study set out to determine the prevalence of Enterobius vermicularis in surgically removed appendices and to assess the possible relation of the parasite to acute appendicitis. All 624 surgically removed appendices received in the Department of Pathology, BPKIHS, Dharan, Nepal during 2(1/2) years (August 1999-January 2002) were examined. E. vermicularis was identified in nine (1.62%) appendices from the patients with a clinical diagnosis of appendicitis. The parasite was most frequently seen in histologically normal appendices (6/71) and was rarely associated with histological change of acute appendicitis (3/539). No cases of E. vermicularis infestation occurred in appendices showing chronic inflammation or removed during the course of other surgical procedures. E. vermicularis was found more frequently in uninflamed and histologically normal appendices (8.45%) than those which were inflamed with histopathologic changes of acute appendicitis (0.56%). It may be a cause of symptoms resembling acute appendicitis although the mechanism for this does not involve mucosal invasion by the parasite.

Mature teratoma is the most common germ cell tumor and accounts for 40.50% of all ovarian neoplasms. The high prevalence of germ cell tumors of the ovary found among patients who were hill natives needs to be explored further.

Vaccination against hepatitis B virus has rarely been associated with lichen planus. We report a case of this kind in a child from Nepal. A 12-year-old boy had developed generalized itchy violaceous papules and plaques six weeks after the second dose of hepatitis B virus vaccine. Serum HBsAg and HBeAb were negative, but HBsAb was positive. New crops of generalized, similar eruptions developed after the booster dose of vaccine. All the lesions resolved within three months of systemic steroid therapy. There was no recurrence after one year of follow up. Awareness of such an association is necessary, especially in children, because vaccination campaigns are increasing.