Aim Lung adenocarcinoma (ADC) is a leading subtype of lung cancer, histologically defined with five different architectural growth patterns: lepidic, acinar, papillary, solid and micropapillary. The aim of this study was to explore the prevalence of epidermal growth factor receptor (EGFR) mutation and a relationship between the specific histological patterns of lung ADC in the population of Bosnia and Herzegovina. Methods The study included tumour tissue from 102 patients with completely resected lung ADC from 2015 to 2020. Molecular testing for the presence of EGFR mutations was performed by real-time PCR method. The relationship between EGFR mutation status and clinicopathological parameters was analysed. Results The EGFR mutation was detected in 12 (11.8%) cases of ADC, more often in non-smokers (p=0.007). A higher percentage of solid growth pattern presented in ADC may be an indicator of EGFR negativity (p=0.039), while a higher percentage of micropapillary growth pattern more common in the presence of EGFR mutation (p=0.047). Conclusion The prevalence of EGFR mutation is in accordance with the expected prevalence considering our studied population, Caucasians from South Europe. Better understanding of the relationship between histological patterns and molecular characteristics of lung ADC will enable earlier diagnosis and optimal treatment for patients.

PURPOSE The aim of this retrospective study was to evaluate and compare diagnostic accuracy and complication rates of percutaneous computed tomography (CT)-guided biopsies of pulmonary lesions 10-35 mm, 35-50 mm, and >50 mm, using the coaxial biopsy technique. METHODS Over a 4-year period, 235 lung biopsies were performed using the coaxial biopsy technique with 18G semi-automated true-cut needle. There were 163 (69.4%) male and 72 (30.6%) female patients, with a mean age of 64.01±9.18 years (18-85 years). The mean lesion size was 59.6±29.3 mm. The lesions were stratified into three groups according to size: lesions <35 mm (n=42, 17.9%), lesions 35-50 mm (n=53, 22.5%), and lesions >50 mm (n=140, 59.6%). Diagnostic accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated for all biopsies, and for each group separately, as well as the incidence of complications. RESULTS The overall diagnostic accuracy was 95.4%, with 95.52% sensitivity, 100% specificity, 100% PPV, and 47.37% NPV. For lesions <35 mm, diagnostic accuracy, sensitivity, and PPV were 100%. The lowest diagnostic accuracy was 93.9% in lesions >50 mm, with 93.65% sensitivity, 100% specificity, 100% PPV, and 42.86% NPV. An adequate sample was obtained in 219 core biopsies (93.2%), while 16 biopsies (6.8%) were nondiagnostic due to necrosis (4.25%) and insufficient biopsy material (2.55%). The most frequent complication was minor pneumothorax, which was seen at a rate of 19.1%; pneumothorax requiring chest tube placement occurred in 3 patients (1.3%). CONCLUSION Diagnostic accuracy decreased with increasing lesion size. On the other hand, complication rates were higher in smaller lesions, more distanced from the pleura.

Aim To examine whether preoperative tumour size may serve as a biomarker for the occurrence of lymphovascular invasion (LVI) in centrally and peripherally located lung adenocarcinoma. Method The study included 261 patients surgically treated for diagnosed lung adenocarcinoma. A ROC curve was used to determine the biomarker potential of tumour size relative to the occurrence of LVI. Binary logistic regression was used to show changes of tumour size impact on the status of LVI. Result Tumour prevalence according to localization had no statistical significance (p=0.464), while the presence of LVI in central, as well as peripheral positions, was statistically significantly different (p<0.001). The area under the curve of 0.978 highlights the fact that tumour size is an excellent marker of the presence of LVI in centrally located adenocarcinomas of the lung. A similar finding was confirmed in peripherally located lung adenocarcinomas with an area below the curve of 0.943. Binary logistical regression showed that in centrally localized adenocarcinomas of the lung, each additional centimetre of tumour growth represents an increase in the likelihood of LVI+ by 17.14 times. In peripherally located adenocarcinomas of the lung, this increase in likelihood of LVI for each centimetre of growth was 5.46 times. Conclusion With a high degree of sensitivity and specificity, preoperative tumour size may serve as an important biomarker and positive predictor of the presence of LVI in lung adenocarcinoma of any location.

A questionnaire on biomarker testing previously used in central European countries was extended and distributed in Western and Central European countries to the pathologists participating at the Pulmonary Pathology Society meeting 26–28 June 2019 in Dubrovnik, Croatia. Each country was represented by one responder. For recent biomarkers the availability and reimbursement of diagnoses of molecular alterations in non-small cell lung carcinoma varies widely between different, also western European, countries. Reimbursement of such assessments varies widely between unavailability and payments by the health care system or even pharmaceutical companies. The support for testing from alternative sources, such as the pharmaceutical industry, is no doubt partly compensating for the lack of public health system support, but it is not a viable or long‐term solution. Ideally, a structured access to testing and reimbursement should be the aim in order to provide patients with appropriate therapeutic options. As biomarker enabled therapies deliver a 50% better probability of outcome success, improved and unbiased reimbursement remains a major challenge for the future.

Introduction: Transverse colon volvulus is an uncommon cause of bowel obstruction. Predisposing factors are mental retardation, dysmotility disorders, chronic constipation, and congenital megacolon. Case report: We presented a transverse colon volvulus in a 14-year-old girl with mental retardation. Chronic constipation in neurologically impaired patients was a risk factor predisposing to volvulus. The girl was admitted to our Clinic because of problems that last 4-5 days and was followed by abdominal pain, vomiting and lack of stool. Vomiting was once a day. She was sub febrile up to 37.6°C. On examination, the abdomen was distended, tense, diffusely painful. During the surgery, a 360° clockwise volvulus of the transverse colon was found. After the reduction of volvulus, an enormous transverse colon was resected and protective ileostomy was formed. In the postoperative period, ileostoma functioned a good. The definitive surgical treatment was done on the 20th postoperative day when the occlusion of the ileostomy and transanal biopsy of the rectum was done, which showed the presence of ganglia cells. The patient was discharged from our institution after 1 month. Conclusion: Pediatric patients with neurological conditions and mental retardation present an increased risk of colon transversum volvulus due to chronic obstruction.

The odontogenic keratocyst (OKC) may occur at any age. However, it mostly occurs during the second and third decades of life. Compared to other odontogenic cysts, this type occurs with a frequency of 5-15%. It is more common in the mandible region and in the male sex. Histologically, odontogenic keratocysts are characterized by the presence of an external connective tissue capsule, with keratinizing lining of the epithelium consisting of 5-8 cell layers with marked palisadisation of polarized basal cells and a corrugated parakeratin layer. The objective of this study is to present cases of odontogenic keratocysts, with reference to the latest classification and dilemmas in therapeutic doctrine. This project was realized in the form of descriptive studies, specifically in a series of cases. A collection of four individual cases was found at the Department of Oral Surgery. Due to the proper approach towards diagnosis, adequate and detailed histopathological analysis, and suitable therapeutic procedures, all cases of odontogenic keratocysts were successfully treated without complications. Enucleation of OKC, with a regular follow-up, proved to be the effective therapeutic choice for the patients described in this paper. Only in the case of recurrence would we consider other therapeutic options, primarily enucleation in combination with Carnoy's solution.

In the early stages of cutaneous malignant melanoma (MM), it is extremely difficult to predict adequately the risk from hematogenic and lymphatic metastasis. We investigate whether the immunohistochemical expression of Ki-67 and estrogen receptor beta (ER&bgr;) in cells of MM could predict the status of regional lymph nodes. A total of 55 tissue samples of primary cutaneous melanomas with known status of regional lymph nodes were retrospectively evaluated for Ki-67 and ER&bgr; expression by quantitative immunohistochemistry and then correlated with the status of regional lymph nodes and relevant clinicopathologic parameters. The ER&bgr;-positive expression was detected in 38 of 55 tumors (69.09%). The Clark level showed a strong correlation with ER&bgr; expression, as well as pT stage. All cases of MM showed Ki-67-positive expression and an elevated Ki-67 expression was strongly associated with increased Breslow thickness, Clark level, ulceration, lymphovascular invasion, number of mitosis, and pT stage. Logistic regression analysis showed that when ER&bgr; levels increase by 1%, the risk of positive lymph nodes decreases by 7% (odds ratio=0.930; 95% confidence interval, 0.87-0.99; P=0.036), and, when the Ki-67 expression increases by 1%, the risk of lymph nodes’ positivity increases by 10% (odds ratio=1.108; 95% confidence interval, 1.02-1.19; P=0.009). Correlation between expression of Ki-67 and ER&bgr; and the status of lymph nodes has better prognostic significance than the relationship between melanoma thickness and the status of lymph nodes. Our study showed a significant prognostic value of Ki-67 expression in predicting the behavior of MM and the potential prognostic significance of ER&bgr;.