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Objective: Colorectal carcinoma (CRC) is extremely rare in childhood and has a poor prognosis in young patients. The tumorigenesis of CRC in children and adolescents is still unclear and probably evolves through different stages. There are not enough studiesabout the rarity of K-ras mutations with childhood CRC. This study aimed to investigate the features and outcomes of childhoodCRC as well as examine the frequency of K-ras mutations in CRC among children and adolescents.Methods: The clinical and pathologic features, prognostic factors, and outcomes of CRC in 28 children and adolescents (ages 10to 17 years) referred to the Pediatric Oncology Department of Hacettepe University Children’s Hospital between 1974 and 2010were reviewed for this study. Paraffin-embedded tissues of 18 patients were available and these tissues were analyzed by using the“pyrosequencing” method to detect K-ras mutations.Results: The median age of patients was 14 years and the male/female ratio was 2.5/1. At presentation, the most common symptoms were abdominal pain (57%) and weight loss (43%). The time between symptoms and diagnosis was 4 months. The mostcommon sites of involvement were the rectum (43%) and sigmoid colon (25%). Mucinous adenocarcinoma was the most common histiotype (71%). At presentation, 89% of patients had metastatic disease, especially to the peritoneal surface (39%). Overallsurvival rates at 3 and 5 years were 10%. Distant stage (p=0.045), incomplete resection, and macroscopic tumor (p=0.000) werepoor prognostic outcomes. A K-ras mutation was identified in three of the 18 patients (17%). The most common mutation of thepatients was GGT→GAT at codon 12.Conclusion: Childhood colorectal carcinomas occur in a shorter time than in adults, with different histiotypes and more likelydifferent steps. It seems that K-ras mutation plays a role in this different biology of pediatric CRC. However, further studies areessential to investigate and understand the biology of childhood CRC.

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Objective: We sought to obtain information on the number of thymic lesions, surgical method, histopathology. We also investigated the relationship between thymic lesions and myasthenia gravis.Methods: We retrospectively examined patients who underwent thymectomy for different thymic pathologies in our clinic between February 1998 and April 2014 according to their demographic characteristics, symptoms, surgical method, resection width,and histopathological diagnosis.Results: The proportion of men and women was similar. The average age was 40.6±14.7 years. The most common symptom wasrapid fatigue and the most common surgical method was median sternotomy. During extended thymectomy, we resected andrecontructed the anatomical structures. We found a high degree of association between thymoma and myasthenia gravis. Theaverage life expectancy of the patients was 171.8±8.8 months.Conclusion: Although the indications of thymectomy are not well known, the surgical procedures vary. We would therefore continue developing ourselves as the center where these surgeries are most frequently performed in the Southeastern Anatolia Region.

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Objective: There is a tendency for thromboembolic events (TE) in Cushing’s disease (CD) because of the cortisol excess itself andassociated risk factors for TE. Whole blood viscosity (WBV) as a measure of hemorheological features may impact the developmentof TE. However, limited data are available on the status of these changes in CD. Herein, we aimed to compare WBV between patients with CD and the control group and evaluate the impact of CD treatment on WBV.Methods: A total of 34 patients with CD without prior TE history and 30 subjects as the control group were enrolled between 2015and 2020. Demographic, clinical, and laboratory characteristics of the study groups were recorded. WBV was calculated using thede Simone formula.Results: Among the corticotroph pituitary adenomas of the CD group, 32 of 34 were microadenomas, and 2 were macroadenomas.Postoperative remission was achieved in all patients. However, a recurrence was observed in 10 patients at 5.8±3.2 year follow-up.There was no difference between baseline WBV, at both low and high shear rates, between the CD and control groups (p>0.05).Furthermore, the WBVs at both low and high shear rates were also similar before and after treatment in the CD group (16.3±1.8versus 15.4±1.7, p=0.2, for WBV at the high shear rate; 40.5±38.2 versus 25.4±35.2, p=0.23, at the low shear rate).Conclusion: In this small-sized preliminary study, the WBV at both shear rates revealed no difference between the CD and controlgroups. There was also no impact of CD treatment on WBV at follow-up. However, further large-scale studies are necessary toconfirm our study findings.

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Objective: Ultrasonography (US) is a useful, easy, and accurate screening method for the diagnosis of neonatal developmental dyspla- sia of the hip. The purpose of this prospective and cross-sectional study is to determine the optimal timing of US for the evaluation of the hip joints in newborns. Methods: We enrolled consecutive 27 [18 girls (66.7%) and nine boys (33.3%)] newborns in this study. Two experienced radiologists (S .T. and M.O ̈ .) performed standard hip US examinations at the 1st and 5th weeks of age according to the method described by Graf. We assessed the relationship between femur head and acetabulum and compared the results of evaluation obtained between the 1st and 5th weeks. Additionally, we evaluated the agreement between the two radiologists. Results: None of the babies were found to have subluxation or dislocation by clinical examination. The US measurements regarding the ossification and the diameter of femur head, bony, and cartilaginous roof at the 1st and 5th weeks were similar (for all infants, P > .05). In our series, no hip was defined as Graf’s type IIb or higher. In total, four (14.8%) right hips and six (22.2%) left hips (total 10 hips) were classified as Graf’s type IIa (physiologically immature) at the 1st week of evaluation. A total of seven hips spontaneously returned to their normal positions during the following 4 weeks. However, two (7.4%) right and one (3.7%) left hip joints were still classified as type IIa at the 5th week of evaluation. Graf type of hips was reported as similar in all the infants by the 1st and 5th week of measure- ments (n ¼ 54, P > .05, for each). There was no interobserver variability between the two radiologists with respect to Graf’s classifica- tion (j > 0.81). The blunt/round shape of acetabular rim defined in 10 hips at the 1st week was improved to an angular shape in the eight hips at the 5th week (P ¼ .008). Conclusion: Early US screening along with normal physical examination can diagnose some hip disorders in babies. Most of the abnor- mal findings detected at the 1st week of US screening recovered spontaneously at the 5th week. Infants with normal US measurements at the 1st week may be excluded from the follow-up, and those with suboptimal findings may be monitored by physical examination and repeated US scans.

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Objective: Paranasal sinus (PNS) osteomas are rare, but the most common benign bone tumors of the paranasal region that can remain asymptomatic until reaching certain size are usually diagnosed incidentally. This study aimed to evaluate the factors that determine the surgical approach to PNS osteomas. Methods: This retrospective study included 22 patients who underwent surgery for PNS osteoma between January 2012 and December 2018. Demographic characteristics, tumor location and size, symptoms, surgical techniques, and postoperative complications were analyzed retrospectively. The relationship between the location and size of the osteoma and the surgical approach was investigated. Results: Of the 22 patients who underwent surgery for PNS osteoma, eight (36.3%) and 14 (63.7%) were women and men, respectively. The mean age of the patients was 39.1 years (range, 21–54 years). Based on their PNS location, osteomas were found in the ethmoid, frontal, maxillary, and both frontal and ethmoid sinuses in 10 patients (45.4%), eight patients (36.3%), three patients (13.6%), and one (4.5%) patient, respectively. The tumor was excised using the osteoplastic flap technique in five (22.7%) patients with frontal sinus osteomas larger than 2 cm in size. A combination of the Caldwell–Luc and transnasal endoscopic techniques was used in three (13.6%) patients with maxillary sinus osteomas. The tumor was excised using the lateral rhinotomy technique in one patient (4.5%) with a giant osteoma in the ethmoid sinus. Osteoma excision was performed using a transnasal endoscopic approach in the remaining 12 patients with ethmoid (n ¼ 9) and frontal sinus (n ¼ 3) involvement. Conclusions: Although the tendency to perform minimally invasive and less morbid transnasal endoscopic approaches in PNS osteoma surgery is increasing, open surgical techniques and combined approaches should be preferred for ethmoid and frontal sinus osteomas with potential complications and which extend beyond the PNS boundaries. PNS osteoma size and localization, surgical equipment, endoscopic sinus surgery experience, and experience in open surgical techniques are the determinants for the surgical approach in PNS osteoma surgery.