Introduction. The term intracholecystic papillary-tubular neoplasm (ICPN) is suggested by some authors for a group of exophytic lesions of the gallbladder. In our study, demographic, pathological, and immunohistochemical features of 45 ICPN cases and their relationship with invasive carcinoma were analyzed. Material and methods. A total of 45 ICPN cases were retrieved out of 7334 cholecystectomies performed between1996 and 2014. Cases were evaluated with regard to demographic, pathological, and immunohistochemical features. Correlation between the clinical and histopathological data and occurrence of invasion was sought. Results. The incidence of ICPN was 0.61% in our series. Invasive carcinoma was observed in 56% of cases. Factors associated with invasion were diffuse high-grade dysplasia (P = .002), papillary growth pattern (P = .001), greatest diameter of the lesion, and high Ki67 proliferation index (P < .0001). Discussion. Some authors have reported that small intracholecystic exophytic lesions without high-grade dysplasia are considered to be inconsequential. However, there are not enough data concerning the features of large lesions with high-grade dysplasia and their prognoses. Our data suggest that cases with diffuse high-grade dysplasia and tubulopapillary/papillary growth pattern, large tumor size, and high Ki67 proliferation index should be studied for the presence of invasion.

Basosquamous carcinoma is a rare cutaneous tumour that is considered an aggressive type of basal cell carcinoma with an increased risk of recurrence and metastases. This impression has been perpetuated in the literature, despite limited scientific data and conflicting results of some authors. This present study was aimed to evaluate the clinical-pathological features of this tumour and follow-up of a series of basosquamous carcinoma. Basosquamous carcinoma patients who underwent surgical excision between January 2000 and February 2012 were analyzed retrospectively. Their medical files were reviewed and the corresponding routinely stained sections (with hematoxylin-eosin) were re-evaluated by two pathologists. Thirty-five patients with basosquamous carcinoma were operated on in this period. Most tumurs were located in the head and neck area (94%), and the mean age of the patients was 69.8 years. Margin involvements were seen in 11 patients (31.4%) and all of them underwent re-excision. There was only one local recurrence. There was neither regional lymph node nor distant metastasis in this series. The recurrence rate of basosquamous carcinoma is found as 4%, lower than that of most other similar studies. Further pathologic studies are needed to better classify basosquamous carcinoma and to increase consistency between the results of studies. Surgical excision and regular follow-up are considered as the treatment of choice.

Although osteosarcoma is the most common primary malignant tumour of bone, osteosarcomas of jaw are rare. In osteosarcomas of jaw, evaluating the clinicopathological factors affecting the prognosis is not easy because of different approaches to diagnosis, treatment, and follow-up. This study reviewed 14 cases of JOS that were diagnosed between 1990–2010, in terms of age, gender, site, clinical history, histopathologic type and histopathologic grade, treatment, and prognosis. Median age was 35 years, while male:female ratio was 1.8:1. Eight tumours were located in the mandible. Osteoblastic differentiation was the predominant feature in seven cases followed by chondroid osteosarcoma (four cases), fibroblastic osteosarcoma, low-grade (parosteal) osteosarcoma associated with fibrous dysplasia, and postradiation osteosarcoma (one cases each). During follow-up, recurrence was seen in four patients at least once and they all died. In conclusion, early diagnosis and complete resection seems to be effective in prognosis. Therefore, clinicians and pathologists should be aware of its characteristics and main differential diagnosis to avoid late recognition.

Objective: It is now important to distinguish between adenocarcinoma and squamous cell carcinoma of the lung because of target-specific treatments. Our study aimed to study the efficiency of Thyroid Transcription Factor-1 (TTF-1), cytokeratin 5/6 (CK5/6) and p63 in distinguishing between adenocarcinoma and squamous cell carcinoma and to study the contribution of these markers to the diagnosis in non-small cell lung cancer. Material and Method: Immunohistochemically, TTF-1, CK 5/6 and p63 were used in 72 cases of squamous cell carcinoma, 19 cases of adenocarcinoma, and 29 cases of non-small cell lung cancer whose final diagnosis was decided with the subsequent resection material. The specificity, sensitivity, and positive and negative predictive value were calculated for each marker. Results: TTF-1 positivity was seen in none of the 72 squamous cell carcinomas but in all of 19 adenocarcinoma cases. CK5/6 negativity was seen in all cases of adenocarcinoma and in two cases of squamous cell carcinoma. p63 was positive in all squamous cell carcinomas and in 4 adenocarcinomas. Cytokeratin 5/6, p63 positivity and TTF-1 negativity were observed in 17 non-small cell lung cancers whose final diagnosis was squamous cell carcinoma. None of the 12 non-small cell lung cancers whose final diagnosis was adenocarcinoma exhibited positive staining for CK5/6. However, p63 staining was not seen in the biopsy but was focal in the surgical specimen in one case. All the 12 non-small cell lung cancers whose certain diagnosis was adenocarcinoma were positive for TTF-1. TTF-1, CK 5/6 and p63 seem to be useful for differentiating adenocarcinoma from squamous cell carcinoma with 100% specificity, 100% sensitivity and 100% specificity, 97% sensitivity and 87% specificity, and 100% sensitivity, respectively. Conclusion: We concluded that TTF-1 is a reliable marker for subtyping lung cancer. Different staining patterns can be seen with CK5/6 and p63; however, if they are used together with TTF-1 and interpreted correctly, they can be of help for the final diagnosis even in cases in which the morphology is unclear.