ORGINAL PAPER<br>Pulmonary abscesses – aetiology and treatment. Ten-year experience of the Department of General and Thoracic Surgery in Lodz, Poland

Introduction: Primary lung abscess is a disease developing due to aspiration or embolization of the infected material from the lung tissue or on the basis of other diseases of different aetiology (secondary abscess). In the research, the authors referred to the aetiology and pathomorphology of lung abscesses and described modern methods of diagnosis and treatment. Material and methods: We treated 89 patients with lung abscess for over 10 years. The main aetiological causes were pneumonia (30%), choking (16,8%), aspiration of the foreign object (10%), injuries (8%) and unknown (21%). We evaluated bacterial flora from the abscess in 61 cases (68.5%). In surgical treatment, we applied resection of the lung tissue – 67 (anatomical – 32, unanatomical – 35), transcutaneous drainage – 9, pleural drainage – 11, cavernostomy – 2. Results: Positive results such as expansion of the lung, regression of the septic state and the possibility to discharge the patient home was obtained in 72 patients (80.9%). 26 patients developed severe complications, seven of which (7.9%) died in an early postoperative period (30 days from the surgical intervention). Conclusions: Surgical treatment of lung abscesses requires an individual approach to each patient regarding his general condition, aetiology, dimensions and the location of the lung abscess, presence of coexisting diseases and possible postoperative course of the disease. Patients with lung abscesses directed to surgical treatment are a specific group because of their poor general condition and lack of possibilities of conservative treatment, which influence the unsatisfactory outcome of treatment

Role of Beta-Carotene in Lung Cancer Primary Chemoprevention: A Systematic Review with Meta-Analysis and Meta-Regression

Lung cancer is one of the most common neoplasms globally, with about 2.2 million new cases and 1.8 million deaths annually. Although the most important factor in reducing lung cancer risk is lifestyle change, most patients favour the use of supplements, for example, rather than quitting smoking or following a healthy diet. To better understand the efficacy of such interventions, a systematic review was performed of data from randomized controlled trials concerning the influence of beta-carotene supplementation on lung cancer risk in subjects with no lung cancer before the intervention. The search corpus comprised a number of databases and eight studies involving 167,141 participants, published by November 2021. The findings indicate that beta-carotene supplementation was associated with an increased risk of lung cancer (RR = 1.16, 95% CI = 1.06–1.26). This effect was even more noticeable among smokers and asbestos workers (RR = 1.21, 95% CI = 1.08–1.35) and non-medics (RR = 1.18, 95% CI = 1.07–1.29). A meta-regression found no relationship between the beta-carotene supplementation dose and the size of the negative effect associated with lung cancer risk. Our findings indicate that beta-carotene supplementation has no effect on lung cancer risk. Moreover, when used as the primary chemoprevention, beta-carotene may, in fact, increase the risk of lung cancer

ORGINAL PAPER<br>The estimation of erythropoietin levels in the blood serum and cystic fluid in patients with solitary renal cysts

Introduction: The role of erythropoietin (EPO) in patients with renal cysts remains unclear. Some authors suggest that EPO may be produced in renal cysts (RC). The aim of the study was to answer the question why concentration of EPO in the cystic fluid (fEPO) is higher than the serum level of EPO. Material and methods: Serum levels of EPO (sEPO) and cystic fluid levels of EPO (fEPO) were determined in a group of 33 patients (age ranging from 24 to 56 years) with renal cysts and no symptoms of either renal insufficiency or anaemia. Similar tests (excluding fEPO) were performed in the healthy controls – K (33 adults, age ranging from 26 to 53 years). Haematological parameters and serum urea (UREA) and creatinine (CREA) concentration were also determined. Results: Levels of EPO in the cystic fluid were, on the average 35 times higher than serum levels of EPO. Levels of sEPO in patients with RC were comparable to the control group C. Significantly higher urea levels, lower reticulocyte count, lower haemoglobin concentration and increased anisocytosis of the red cells were found in the study group compared to the control group. Conclusions: The study suggests that in patients with solitary renal cysts there is no erythropoietin penetration from the cyst fluid into the blood serum. The role of high erythropoietin concentration in renal cyst fluid requires further study

Original paper <br>Thyroid neoplasms – errors of the cytological diagnosis

Objectives: the evaluation of the diagnostic value of a cytological examination and its limitations for the diagnosis of thyroid neoplasms.Material and methods: From 1995 to 2004 nine hundred ninety eight patients were operated on for nodular lesions of the thyroid gland in our department. Cytological and histopathologic diagnoses were compared retrospectively in all cases where a neoplasm was suspected (true positive, false negative and false positive diagnoses). The verification was carried out independently by two pathologists. It enabled the establishment of interpretation errors (IE). The cases where cytological and histopathologic diagnoses were incompatible were interpreted as a sampling error (SE).Results: As a result of the verification 45 cytological and histopathologic diagnoses were changed compared with the primary ones. In the analysed material the following diagnoses were put: true positive – 144, true negative – 824, false positive – 12, false negative – 18. The sensitivity of FNAB was 0.89, specificity 0.99, accuracy 0.97 and a positive predictive diagnostic value 0.92. False cytological diagnoses were found in 75 cases (7.5%). In 45 cases (4.5%) a diagnosis was changed compared with a primary one – interpretation error. In the remaining 30 cases (3%) a false diagnosis was caused by a sampling error. Conclusions: FNAB is an examination of high diagnostic value for the detection of thyroid neoplasms in the hands of an experienced pathologist. False cytological diagnoses comprised only a small part (7.5%) of their total number and were caused by interpretation error in 4.5% and by sampling error in 3.0%. The percentage of interpretation errors can be decreased by a multiple independent assessment of samples

Short communication <br> The methods of treatment of an ingrown toenail

An ingrown toenail is an inflammatory process occurring as a result of ingrowing medial or lateral edge of the nail into the nail bed. There are various causes of this ailment. The most common are: wearing poorly fit footwear causing pressure on the nail bed from the outside, improper trimming of toenails, hereditary susceptibility, trauma, hidrosis, presence of a background systemic disease (e.g. obesity, diabetes), onychomycosis and some medicines (applied in psoriasis and protease inhibitors).The treatment depends on the progression of the ailment (preservative or surgical methods).The clinical analysis involved 156 patients suffering from an ingrown toenail and treated from the year 2000 until September 2005 in The Clinic of Thoracic Surgery, General Surgery and Oncology of Clinical University Hospital No. 2.The group included 115 males (74% of patients) and 41 females (26% of patients). The age of patients differed from 25 to 68 years (on average 43 years). We performed 174 operations of marginal resection of the nail and phenolisation of the matrix among 156 patients. 7 patients underwent the procedure on both sides and 4 patients in two toenails.The healing time of the postoperative wounds was 14-18 days. The recurrence of the ailment was found in 4 patients (2.5% of patients). There were no complications such as excessive bleeding or postoperative infection in the study group. The marginal resection of the nail connected with phenolisation of the matrix is a good method of treatment of an ingrown toenail as it causes few recurrences and complications

The Significance of the Alter miR let-7a and miR-335 Expression Level Regulating the CCR7/CCL19 Axis as Potential Biomarkers of Tumor Progression in NSCLC

The chemokine receptor 7/C-C ligand 19 chemokine (CCR7/CCL19) has been implicated in the development and progression of NSCLC. Its expression is regulated by various epigenetic factors including miRNAs. The aim of this study was to assess the expression of CCR7/CCL19 in cancer tissue in relation to that of miRNAs (miR-let-7a, miR-335) as transcriptional regulators. The expression of the tested miRNAs was also evaluated in serum exosomes. Sixty patients (n = 60) were enrolled in the study. The total expression of the studied mRNA and miRNAs were evaluated using qPCR. Tumor tissue fragments, macroscopically unchanged adjacent tissue, and serum were used as controls. Higher CCR7 and CCL19 mRNA expression levels were observed in tumor tissue compared to control. According to stages of the disease (AJCC tumor staging), the greatest expression level of the studied genes’ mRNA was observed in patients with stage III. In NSCLC patients, lower miR let-7a expression level was observed in tumor tissue compared to serum; however, miR-335 expression level was higher (p p > 0.05) with liquid biopsy. Significantly greater miR-335 expression level and lower miR let-7a expression level in serum were observed in patients with metastases to lymph nodes. Our findings reveal a significant correlation between the expression levels of the mRNA of the studied genes and miRNAs. Changes in miR-335 and miR let-7a expression levels in the serum exosomes of NSCLC patients in relation to lymph node metastases and tumor stage may serve as a non-invasive molecular biomarker of tumor progression

Original paper <br>Thoracoscopic splanchnicectomy in chronic epigastric visceral pain therapy

Background: The rapid development of minimal invasive surgery in the 1990s coincided with the introduction of videothoracoscopic splanchnicectomy of nerve fibers engaged in the sensation of chronic pain related with advanced cancer. This study was aimed to determine pain intensity in patients with advanced cancer in the epigastric region before and after thoracoscopic splanchnicectomy. Material and methods: The thoracoscopic splanchnicectomy was performed in 33 patients aged 42 to 77 form 2001 to 2005. Patients with chronic epigastric pain due to advanced cancer were qualified for the surgery. The pain intensity was ranked with Prince Henry Hospital Pain Scale (PHHPS). Results: Even though all study patients were on continuous analgesic medications, the mean pain intensity in PHHPS scale was 2.67 points. Two days and thirty days after the surgery, the pain was ranked 1.28 and 1.57, respectively. All patients decreased the doses of their analgesic medication and seven of them entirely discontinued analgesic therapy. Conclusions: The thoracoscopic splanchnicectomy is well suited, although relatively little known, method of the therapy of chronic pain in advanced malignancy. It may be recommended as an option in the current palliative analgesic therapy

Serum Extracellular Vesicle-Derived miRNAs in Patients with Non-Small Cell Lung Cancer—Search for Non-Invasive Diagnostic Biomarkers

The aim of the study was a search for diagnostic and/or prognostic biomarkers in patients with non-small cell lung cancer (NSCLC) patients, based on circulating microRNAs (miRs: miR-23a, miR-361, miR-1228 and miR-let7i) in extracellular vesicles (EVs). Serum EVs were isolated from NSCLC patients (n = 31) and control subjects (n = 21). RNA was isolated from EVs and reverse transcription reaction was performed. Relative levels of miR-23a, miR-361, miR-1228 and miR-let7i were assessed in real-time qPCR using TaqMan probes. Analysis was based on the 2-ΔΔCT method. Statistically significant lower levels of miR-23a and miR-let7i were observed among NSCLC patients vs. control group: miR-23a, 0.054 vs. 0.107; miR-let7i, 0.193 vs. 0.369 (p = 0.003, p = 0.005, respectively). A receiver operating characteristic (ROC) curve analysis demonstrated the diagnostic potential of each individual serum EV-derived miRNA with an area under the curve AUC = 0.744 for miR-23a (p = 0.0003), 0.733 for miR-let7i (p = 0.0007). The decreased level of miR-23a in patients correlated with metastasis to lymph nodes and with AJCC tumor staging system. The results demonstrate that miR-23a and miR-let7i may prove clinically useful as significant, non-invasive markers in NSCLC diagnosis. Additionally, changing profile level of miR-23a that correlates with cancer development may be considered as an NSCLC progression marker