Diagnostic clues for hyalinizing trabecular tumor on fine needle aspiration cytology.

Objectives: The hyalinizing trabecular tumor (HTT) is a rare benign neoplasm of the thyroid gland. This neoplasm has overlapping cytological features with Papillary Thyroid Carcinoma, Medullary Carcinoma and Follicular Neoplasm with Nuclear Features of Papillary Carcinoma. This can lead to misdiagnosis of malignancy in fine needle aspiration (FNA) cytology specimens with unnecessary total thyroidectomy. The aim of this study is to determine if there are some cytological features that could help us to suspect HTT on FNA specimens and avoid radical surgery. Material and Methods: With this purpose we have collected 6 cases diagnosed of HTT in Hospital Clínico San Carlos of Madrid (Spain) in the last 10 years and reviewed the cytological specimens. Result: We conclude that the presence of hyaline material in FNA specimens of HTT is a constant feature being a diagnostic clue. We must be cautious not to confuse it with dense colloid or amyloid material, the latter seen in Medullary Carcinoma. Papillary architecture and fibrovascular cores are not present in a HTT. Special stains as ki-67, calcitonin and Congo Red staining could help us in achieving the correct diagnosis. Conclusion: We feel the cytopathologists must be aware of the distinguishing features of this lesion, mainly the typical hyaline material to achieve a proper diagnosis and be able to reduce unnecessary aggressive management of these patients.

Histopathologic Changes in Congenital Corneal Stromal Dystrophy: Report of 4 Cases in 2 Families.

Corneal dystrophies are hereditary diseases affecting the corneal tissue; they are bilateral, symmetrical and unrelated to environmental or systemic conditions. Congenital corneal stromal dystrophy is a very rare autosomal dominant dystrophy that is caused by a mutation in the DCN gene that encodes decorin (a proteoglycan of the extracellular matrix). We herein report 4 cases of congenital stromal corneal dystrophy in 2 families, highlighting the previously undescribed histopathologic features, the possible differential diagnosis of this entity and the key role played by decorin staining in its diagnosis.

On-line flow injection molecularly imprinted solid phase extraction for the preconcentration and determination of 1-hydroxypyrene in urine samples.

New analytical strategies tend to automation of sample pre-treatment and flow analysis techniques provided a number of enhanced analytical methods allowing high throughput. Flow techniques are usually faster, more robust and more flexible than their batch equivalents. In addition, flow methods use less sample and reagent amounts and reduce analytical costs and waste. A flow injection solid-phase extraction pre-concentration system using a molecularly imprinted polymer (MIP) packed micro-column was developed for the determination of 1-hydroxypyrene in human urine with fluorescence detection. The pre-concentration of 1-hydroxypyrene on the MIP was carried out based on the specific retention of analyte by on-line introducing the sample into the micro-column system. Methanol and dichloromethane mixture was used to elute the retained analyte for fluorometric analysis. Important influencing factors were studied in detail, in batch and in flow (MISPE procedure optimisation, sample and eluent volumes, flow rate, dimensions of MIP micro-column and amounts of packing material, etc). To the best of our knowledge, this is the first on-line flow injection molecularly imprinted solid phase extraction for the pre-concentration and determination of hydroxylate PAH metabolite in urine samples. The optimised method was successfully applied to the determination of 1-Hydroxypyrene in spiked urine samples, with recoveries in the range of 74-85% and RSD<4.6%. Under optimum experimental conditions, the linearity concentration range used was 10-400µgL-1, R2>0.996. We obtained limit of detection and quantification of 3.1µgL-1 and 10.5µgL-1, respectively.

Laparoscopic treatment of retroperitoneal cystic mesothelioma. Two cases reported.

Retroperitoneal cystic mesothelioma is a very rare lesion. The pathogeny is unclear and establishing a preoperative diagnosis versus others retroperitoneal cystic lesions is difficult. Thus, with increasing experience in laparoscopic retroperitoneal surgery, the use of this approach for exploration of a retroperitoneal mass of unknown origin may provide an alternative to classic open surgery and all the benefits of laparoscopy. We present two cases treated laparoscopycally and review the literature.