Giardia lamblia and Helicobacter pylori coinfection in gastrointestinal biopsies: A retrospective single-center analysis from Switzerland.

BACKGROUND: The protozoan Giardia lamblia (GL) and the bacterium Helicobacter pylori (HP) are common causes of gastrointestinal disease. Coinfection is common and has been reported in studies from Africa, Europe, North America and Asia, but data for Switzerland are scarce. AIM: To investigate GL and HP prevalence and coinfection rate in gastrointestinal biopsies from the Zurich area of Switzerland. METHODS: Cases were retrieved from the laboratory information system (Medica Institute of Clinical Pathology, Zurich, Switzerland). Histological slides of cases with GL were reviewed, as were the concurrent gastric biopsies, where available. RESULTS: Between January 1, 2013 and December 31, 2020, GL was found in 88 (0.14%) of 62,402 patients with a small intestine biopsy and HP in 10,668 (15.5%) of 68,961 patients with a gastric biopsy. 74/88 (84.1%) of patients with GL had unremarkable small intestine biopsies, 13/88 (14.8%) had increased intraepithelial lymphocytes, 5/88 (5.7%) showed villous atrophy and 2/88 (2.3%) acute inflammation. 71/88 patients (80.7%) with GL had an available gastric biopsy, of which 12/71 (16.9%) were unremarkable, 28/71 (39.4%) had HP-associated gastritis, 11/71 (15.5%) showed reactive gastropathy and 1/71 (1.4%) had autoimmune gastritis. CONCLUSION: Coinfection with HP is common in patients with GL in gastrointestinal biopsies from the Zurich area of Switzerland. Therefore, gastroenterologists should consider sampling the stomach when GL is suspected for evaluation of possible concurrent HP-associated gastritis. Likewise, pathologists should scrutinize any small intestine biopsy for the presence of GL when HP-associated gastritis is seen, and vice versa.

Outcome of Beveled versus Vertical IncisionTechnique after Reconstructive or Aesthetic Facial Surgery.

BACKGROUND: We suggest that the degree of scar improvement with a beveled incision technique with an angle of about 20 degrees to the skin can be translated for various reconstructions on the face and can be verified by a validated clinical assessment scale and histology. METHODS: A total of 5 patients (2 men and 3 women) with a mean age of 68 years (range 54-84 years) undergoing elective surgeries on the face for tumor excision or cosmetic procedures were included. The beveled incision technique was compared with the conventional vertical incision (control group). Outcome measures were major and minor complications, pain and scar quality using the Patient and Observer Scar Assessment Scale, and histomorphologic scar assessment. RESULTS: After a mean follow-up of 7.6 months (range 6-13 months), all patients healed uneventfully without pain, hypertrophic scars, or infection. We found a better overall Patient and Observer Scar Assessment Scale score in the beveled incision technique group (15 ± 3.4) compared with the conventional vertical incision group (18.4 ± 7.8, P = 0.7). Histomorphologic analyses showed after 6 months less scar zone, less inflammatory reaction, fewer macrophages, less foreign body reaction, and more hair follicles in the beveled incision technique group compared with the vertical incision group. CONCLUSION: We showed that the beveled incision technique using a 20-degree angle in elective surgeries on the face yields a cosmetic pleasant result for both the patient and the surgeon, which also goes in line with our histomorphologic analyses.

Management of Early-Stage Adenocarcinoma of the Esophagus: Endoscopic Mucosal Resection and Endoscopic Submucosal Dissection.

Barrett's esophagus with high-grade dysplasia and early-stage adenocarcinoma is amenable to curative treatment by endoscopic resection. Histopathological correlation has established that mucosal cancer has minimal risk of nodal metastases and that long-term complete remission can be achieved. Although surgery is the gold-standard treatment once there is submucosal involvement, even T1sm1 (submucosal invasion ≤ 500 µm) cases without additional risk factors for nodal metastases might also be cured with endoscopic resection. Endoscopic resection is foremost an initial diagnostic procedure, and once histopathological assessment confirms that curative criteria are met, it will be considered curative. Endoscopic resection may be achieved by endoscopic mucosal resection, which, although easy to perform with relatively low risk, is limited by an inability to achieve en bloc resection for lesions of size more than 1.5 cm. Conversely, the technique of endoscopic submucosal dissection is more technically demanding with higher risk of complications but is able to achieve en bloc resection for lesions larger than 1.5 cm. Endoscopic submucosal dissection would be particularly important in specific situations such as suspected submucosal invasion and lesion size more than 1.5 cm. In other situations, since endoscopic resection would always be combined with radiofrequency ablation to ablate the remaining Barrett's epithelium, piecemeal endoscopic mucosal resection would suffice since any remnant superficial invisible dysplasia would be ablated.

Board examination for anatomical pathology in Switzerland: two intense days to verify professional competence.

About 15 years ago, the Swiss Society of Pathology has developed and implemented a board examination in anatomical pathology. We describe herein the contents covered by this 2-day exam (autopsy pathology, cytology, histopathology, molecular pathology, and basic knowledge about mechanisms of disease) and its exact modalities, sketch a brief history of the exam, and finish with a concise discussion about the possible objectives and putative benefits weighed against the hardship that it imposes on the candidates.

Human papillomavirus infection among women with cytological abnormalities in Switzerland investigated by an automated linear array genotyping test.

Limited data are available describing human papillomavirus (HPV) genotype distribution among females with cytological abnormalities in Switzerland. Cervical cell specimens obtained from 5,318 women were screened routinely by liquid-based Pap smear. All specimens with cellular abnormalities were analyzed subsequently for HPV DNA by the Linear Array HPV genotyping test. Cellular abnormalities were found in 202 (3.8%) specimens, of which 150 (74.3%) were positive for high-risk (HR) HPV. HR-HPV was detected in 20 (60.6%; 95% CI, 43.7-75.4%) of 33 specimens with atypical squamous cells of undetermined significance compared to 98 (72.1%; 95% CI, 64-78.9%) of 136 low-grade squamous intraepithelial lesions and 32 (97%; 95% CI, 83.4-99.9%) of 33 high-grade squamous intraepithelial lesions. The cumulative prevalence of HR-HPV other than HPV 16 and 18 was significantly higher than HPV 16 and/or 18 lesions with atypical squamous cells and low-grade lesions and was comparable in high-grade squamous intraepithelial lesions. The most common HR-HPV genotypes were HPV 16 (15.2%), HPV 31 (12.1%), HPV 58 (12.1%), HPV 51 (9.1%), and HPV 59 (9.1%) in women with atypical squamous cells, HPV 16 (25%), HPV 51 (16.9%), HPV 52 (11.8%), HPV 31 (9.6%), and HPV 56 (8.1%) in women with low-grade lesions (LSIL) and HPV 16 (57.6%), HPV 18 (18.2%), HPV 31 (15.2%), HPV 52 (12.1%), and HPV 58 (6.1%) in women with high-grade lesions (HSIL).

Automation of the linear array HPV genotyping test and its application for routine typing of human papillomaviruses in cervical specimens of women without cytological abnormalities in Switzerland.

BACKGROUND: There is a need for reliable, automated high throughput HPV detection and genotyping methods for pre- and post-prophylactic vaccine intervention analyses. OBJECTIVES: To optimize the linear array (LA) HPV genotyping test (Roche Diagnostics, Rotkreuz) in regard to possible automation steps for the routine laboratory diagnosis of HPV infections and to analyze the HPV genotype distribution in cervical specimens of women without cytological abnormalities in Switzerland. STUDY DESIGN: 680 cervical cell specimens with normal cytology, obtained from women undergoing routine cervical screening by liquid-based Pap smear, were analyzed by the LA HPV genotyping test for HPV-DNA. RESULTS: The automation of the LA HPV genotyping test resulted in a total hands-on time reduction of 255 min (from 480 to 225 min; 53%). Any of 37 HPV genotypes were detected in 117 (17.2%) and high-risk (HR) HPV in 55 (8.1%) of 680 women with normal cytology. The highest prevalence of any HPV (28.1%) and HR-HPV (15.1%) was observed in age-group 21-30 and showed a continuous decrease in older age-groups. The most common HR-HPV genotypes were HPV-16 (12%), HPV-31 (9.4%), HPV-52 (6%), HPV-51 (5.1%), HPV-45 (4.3%), HPV-58 (4.3%) and HPV-59 (4.3%). CONCLUSIONS: The optimization and automation of the LA HPV genotyping test makes it suited for high throughput HPV detection and typing. The epidemiological data provides information about distribution of HPV genotypes in women without cytological abnormalities in Switzerland and may be important for determining the future impact of vaccines and potential changes in the country's epidemiological HPV profile.

Defective DNA mismatch repair determines a characteristic transcriptional profile in proximal colon cancers.

BACKGROUND & AIMS: Colon cancers with defective DNA mismatch repair (MMR) have peculiar molecular, pathologic, and clinical features, including high-level microsatellite instability, conspicuous lymphocytic infiltration, preferential location in the proximal colon, and better prognosis. Our aim was to characterize the transcriptional profile of this colon cancer subset. METHODS: An oligonucleotide microarray containing 12,625 probes was used to evaluate gene expression in 25 proximal colon cancers, 10 samples of normal colon mucosa, and 14 colon cancer cell lines. Transcriptional profiles of MMR-deficient cancers and cell lines were compared with those of their MMR-proficient counterparts. RESULTS: Unsupervised analysis of microarray data showed that MMR status exerts a predominant influence on the gene expression profile of proximal colon cancers. Hierarchical clustering divided the cancers into 2 groups corresponding almost perfectly with their MMR status. Supervised analysis identified numerous gene expression changes that represent a genetic signature of MMR-deficient colon cancers. Changes in genes involved in apoptosis and the immune response were consistent with the better prognosis of MMR-deficient cancers. In MMR-deficient cancers and cell lines, 4-1BBL, a crucial gene in the anti-tumor immune response, was, respectively, 2.4 and 6.0 times more expressed than in their MMR-proficient counterparts. This difference was confirmed by quantitative reverse-transcription polymerase chain reaction and flow cytometric assessment of 4-1BBL protein expression in colon cancer cell lines. Our analysis also showed novel possible gene targets of microsatellite instability. CONCLUSIONS: MMR inactivation produces distinct changes in the cellular messenger RNA pool, which is consistent with a unique tumorigenesis pathway.

Immunohistochemical analysis reveals high frequency of PMS2 defects in colorectal cancer.

BACKGROUND & AIMS: Germline mutations in the DNA mismatch repair (MMR) genes MSH2, MSH6, or MLH1 predispose to colorectal cancer (CRC) with an autosomal dominant inheritance pattern. The protein encoded by PMS2 is also essential for MMR; however, alterations in this gene have been documented only in extremely rare cases. We addressed this unexpected finding by analyzing a large series of CRCs. METHODS: Expression of MSH2, MSH6, MLH1, and PMS2 was studied by immunohistochemistry in 1048 unselected, consecutive CRCs. Where absence of MMR proteins was detected, microsatellite instability and cytosine methylation of the respective gene promoter were analyzed. The DNA of patients presenting with PMS2-deficient cancers was examined for germline and somatic alterations in the PMS2 gene. RESULTS: An aberrant pattern of MMR protein expression was detected in 13.2% of CRCs. Loss of expression of MSH2, MSH6, or MLH1 was found in 1.4%, 0.5%, and 9.8%, respectively. PMS2 deficiency accompanied by microsatellite instability was found in 16 cases (1.5%) with a weak family history of cancer. The PMS2 promoter was not hypermethylated in these cases. Despite interference of the PMS2 pseudogenes, we identified several heterozygous germline mutations in the PMS2 gene. CONCLUSIONS: PMS2 defects account for a small but significant proportion of CRCs and for a substantial fraction of tumors with microsatellite instability. However, the penetrance of heterozygous germline mutations in PMS2 is considerably lower than that of mutations in other MMR genes. The possible underlying causes of this unorthodox inheritance pattern are discussed.

PTEN as a molecular marker to distinguish metastatic from primary synchronous endometrioid carcinomas of the ovary and uterus.

The distinction between two primary carcinomas on the one hand and a metastatic disease on the other hand in patients suffering from synchronous endometrioid carcinomas of the uterus and ovary is difficult. Exclusive histopathologic analysis appears to be insufficient and sometimes misleading. The tumor suppressor PTEN was found to be important in early neoplastic transformation in endometrioid carcinomas of the uterus. In this study, we screened synchronous endometrioid carcinomas of the uterus and ovary of 10 patients for loss of heterozygosity using seven different microsatellite markers at 10q23.3 and for mutations in the entire coding region of PTEN. Point mutations or microdeletions/insertions were found in six patients. Allelic loss at 10q23.3 was detected in eight patients. Based on conventional histology, a metastatic disease was diagnosed in seven patients and a concomitant uterine and ovarian carcinoma in three patients. After molecular analysis, the histopathologic diagnosis of three patients had to be revised. Histopathology represents the standard method to process tumor specimens from these patients. Nevertheless, mutation screen for PTEN and LOH analysis at 10q23.3 provide helpful genetic tools to establish a correct final diagnosis, which is important in view of prognosis and therapeutic implications.