Cüneyt Yurdakul

Clear cell atypical fibroxantoma: a rare variant of atypical fibroxanthoma and review of the literature.

Atypical fibroxanthoma (AFX) is a superficial variant of pleomorphic malignant fibrous histiocytoma. Clear cell atypical fibroxanthoma (CCAFXA) is a rare variant of atypical fibroxanthoma. A 74-year-old male patient presented with a rapidly growing nodule on the shoulder, which had appeared over a 5-months period. Lesion was excised by the plastic surgeon. Microscopic examination showed an ulcerated nodule composed of pleomorphic spindled and polygonal cells with clear or vacuolated cytoplasm. The neoplastic cells were stained positively with CD68 and CD10 and were stained negative with S-100, Melan A, muscle-specific actin, or pan-cytokeratin. Final diagnosis was clear cell atypical fibroxanthoma. CCAFXA should be differentiated from other clear-cell neoplasms of the skin. Best of our knowledge only 11 cases CCAFXA of have been reported in published studies till date. Herein, we reported 12th case in literature of CCAFXA and review of the literature.

The Role of p16, p21, p27, p53 and Ki-67 Expression in the Differential Diagnosis of Cutaneous Squamous Cell Carcinomas and Keratoacanthomas: An Immunohistochemical Study.

BACKGROUND Distinguishing squamous cell carcinoma (SCC) from keratoacanthoma (KA) by histopathological features may not be sufficient for a differential diagnosis, as KAs may, in some cases, imitate well-differentiated SCCs. AIMS In this study, we investigated whether the expression of the p16, p21, p27, p53 genes and a Ki-67 proliferation index are useful in distinguishing between these two tumors. STUDY DESIGN Cross-sectional study. METHODS Immunohistochemistry was used to investigate the expression of the p16, p21, p27, p53 genes and the Ki-67 proliferation index was investigated in well-differentiated SCC with KA-like features (n=40) and KA (n=30). RESULTS The results of all of the examined markers, except for p27 (p16, p21, p53, and Ki-67) were found to be significantly different between the SCC and KA samples (p<0.05). CONCLUSION In well-differentiated SCC with KA-like features and KA cases where the differential diagnosis is difficult from a histopathological perspective, the use of p16, p21, p53 expression and a Ki-67 proliferation index can be useful for the differential diagnosis of SCCs and KAs.

Relationships Between C-Kit Expression and Mean Platelet Volume in Benign, Preneoplastic and Neoplastic Endometrium

BACKGROUND c-Kit is a proto-oncogene that encodes a tyrosine kinase receptor (CD117). Mean platelet volume (MPV) is a useful marker for demonstrating thrombocyte function. We aimed to investigate whether c-kit is expressed in benign, preneoplastic and neoplastic endometrial tissues and whether MPV has a relation with c-kit expression and its intensity. MATERIALS AND METHODS c-Kit expression was investigated immunohistochemically in 10 samples of normal endometrium (n=10), simple endometrial hyperplasia (5 cases with atypia and 10 cases without atypia), complex endometrial hyperplasia (10 cases with atypia and 10 cases without atypia) and endometrial cancer (EC) (10 cases grade I and 10 cases grade II) and MPV of all cases was checked. RESULTS c-Kit expression was observed at very low rates in cases with normal endometrial tissues (NE) and in hyperplasia without atypia. c-Kit expression and immunostaining were strong in endometrial atypia and EC. MPV levels of complex atypical endometrial hyperplasia (CAEH) (p:0.002), EC grade I (ECG I) (p<0.001) and EC grade II (ECG II) (p<0.001) were significantly elevated when compared with the NE group. Both c-kit expression and intensity of immunostaining had a positive correlation with MPV level. CONCLUSIONS While c-kit expression and intensity of immunostaining were mildly positive in NE and hyperplasia without atypia, they were clearly observed in EC and hyperplasia with atypia. As c-kit expression is related to the mutagenesis a long-term follow- up may be needed in these cases. A high MPV level may be a good test for demonstrating c-kit expression and intensity of immunostaining.

Giant Cell Tumour of the Tendon Sheath: Analysis of 35 Cases and their Ki-67 Proliferation Indexes.

INTRODUCTION A giant cell Tumour of the tendon sheath (GCTTS) is a slow-growing benign Tumour originating from the synovial cells of the tendon sheath. It is the second most common Tumour of the hand. The aim of this study was to perform a retrospective clinicopathological evaluation of GCTTS cases and determine whether the proliferative activity of giant cell tumour of tendon sheath is related to its recurrence rate and local aggressiveness. MATERIALS AND METHODS The age, gender, Tumour location and diameter, treatment mode, Ki-67 proliferation index, mitotic rate, and recurrence were retrospectively evaluated in 35 patients diagnosed with GCTTS in the Department of Pathology, School of Medicine, Recep Tayyip Erdogan University between 2009 and 2014. RESULTS Of the 35 GCTTS cases, 23 were female, and 12 were male. The mean age was 45 y (range 10-70). Sixteen tumours were located in the right hand and 14 in the left hand, and five were in the feet. The mean Tumour diameter was 2.3 cm (0.6-6 cm). All patients underwent marginal excision. The mean postoperative follow-up period was 4 y (range 28 months-5 y). Only six patients showed recurrence. In these cases, the site of GCTTS recurrence was the phalanx of the hand. The mean Ki-67 index in the recurrence cases was 6.5%, whereas it was 2.3% in those without recurrence. CONCLUSION The Ki-67 proliferation index and mitotic activity were increased in recurrent cases compared to nonrecurrent cases. Therefore, these parameters may be helpful in predicting recurrence of GCTTS. However, adequate surgical excision and complete removal of the Tumour are important steps to minimize the recurrence rate.

Chondroid syringoma with extensive bone formation: a case report and review of the literature.

Chondroid syringoma is a rare, skin appendageal tumour, usually reported at the head and neck region. It is a mostly intradermal and rarely subcutaneous small painless nodule. The histopathological examination is characterized by a combination of epithelial and myoepithelial structures within a chondromyxoid and fibrous stroma. Herein, we present a rare case of chondroid syringoma with extensive bone formation.

Basal Cell Carcinoma Arising within Seborrheic Keratosis.

Malignant tumour development within a seborrheic keratosis (SK) is extremely rare. Though the most commonly developed malignant tumour is the basal cell carcinoma (BCC), other tumour types have also been reported in literature. Herein, we will report a superficial type BCC case developed within SK localized in hairy skin of a 78-year-old female patient. In immunohistochemical evaluation, diffuse positive staining with CK19 and over-expression in p53 compared with non-neoplastic areas were determined in neoplastic basaloid islands. It is always not easy to differentiate especially superficial type BCC cases from non-neoplastic epithelium of SK with histopathological evaluation. As far as this reason we believe that in difficult differentiation of these 2 lesions, in order to show the differentiation in basal epithelium, immunohistochemical evaluation may be helpful.

Inflammatory pseudotumor of the epididymis: a case report and review of the literature

Inflammatory pseudotumors (IPTs) are rare benign tumor-like lesions in the epididymis. They result from myofibrohistiocytic proliferation of the parenchymal organs of the body, such as the lungs and genitourinary system. A 48-year-old male patient presented with a palpable left scrotal mass and developed painless swelling within two months. Scrotal ultrasound revealed a 3 cm solid mass and spermatocele sac in the epididymis. Local excision was performed. Histopathologic and immunohistochemical examination revealed an inflammatory pseudotumor. Only ten cases have been reported in the literature to date. We present our case of pseudotumor of the epididymis as the eleventh case reported in the literature with a brief review.

An Unusual Radiological Presentation of a Pulmonary Hydatid Cyst in a Child

Giant pulmonary hydatid cyst is usually encountered in adolescents and children who are older than 10 years. A relatively higher elasticity of the lung tissue allows rapid growth of cysts. We present a case of a 15-year-old male who was admitted with complaint of frequent and persistent dry cough for over a month. Computed tomographic scan revealed a giant cyst with thick enhancing rim and an “air bubble” sign. Diagnosis of giant hydatid cyst was confirmed by surgery and histopathological examination.

The importance of cytokeratin 19 expression in the differentiation of Basal cell carcinoma and trichoepithelioma.

INTRODUCTION Basal cell carcinoma (BCC) is the most common skin neoplasm reported in human. On the other hand, trichoepithelioma (TE) is a rare, benign tumour of skin adnexa. The differentiation of BCC and TE may be difficult since their morphological findings are similar. In a few studies, it has been determined that undifferentiated basaloid cells are highly positively stained with cytokeratin 19. AIM The aim of this study was the comparison of cytokeratin 19 expression in cases of BCC and TE. MATERIALS AND METHODS Sections of skin tissues of 17 TE, 25 BCC and 12 non-neoplastic cases were used for cytokeratin 19 (CK19) immunohistochemical staining. RESULTS Staining with CK19 of the BCC cases gave 15(60%) diffuse, 7 (28%) focal and 3 (12%) negative staining. On the other hand, among TE cases, 2 (12%) gave diffuse, 5 (29%) focal and 10 (59%) negative staining with CK19. In the non-neoplastic skin tissue samples, while positive staining with cytokeratin 19 in the outer root sheath of hair follicles and sweat glands were observed, there was no staining in basal layers. CONCLUSION CK19 expression may be helpful in the differential diagnosis of BCC and TE especially in small skin biopsy samples in which morphologic differentiation is difficult.

A case of rectal neuroendocrine tumor presenting as polyp.

Highlights • Pointing out the rarely seen rectal neuroendocrine tumors (NETs).• Rectal neuroendocrine tumors (NETs) can be presented as polypes.• Emphasizing the importance of classification.• Classifying the variety of treatments.