Correlations Between the Autolytic Changes and Postmortem Interval in Refrigerated Cadavers.

INTRODUCTION: In forensic pathology the autolytic process has been observed and documented in order to determine the postmortem interval as accurately as possible. The observation and experiments have been carried out on cadavers exposed to environmental conditions - heat, humidity, air currents, soil, water. METHODS: For this study hematoxylin and eosin (HE) stained sections of organ samples from 30 autopsied bodies were examined under the microscope. Modifications of tissue and cell structures were noted in correlation with the bodies' time spent in the Morgue's mortuary refrigerator until the autopsy was performed, which varied between 24 hours and 22 days. RESULTS: All the organs sampled (lung, heart, liver and pancreas) showed severe autolytic alterations after 5 to 8 days. The most heavily affected was the pancreas, cells within Langherhans islets becoming complete autolyzed at the 36 hours mark. Inside organs, autolytic processes occur at different rates depending on the locations within that organ -deeply or superficial; in the heart after 4 or more days subendocardic myocardium shows less severe autolytic changes than the subepicardial one. CONCLUSION: Autolytic processes have a delayed onset and a much lower progression rate in a cold controlled environment. Different organs suffer different rates of autolysis in correlation to their structure and enzymatic content.

Multiple Histological Subtypes of Dermatofibrosarcoma Protuberans Occurring in the Same Tumor.

Dermatofibrosarcoma protuberans (DFSP) represents a low-grade cutaneous sarcoma which may have different histological aspects, presenting as a fibrosarcomatous, pigmented, juvenile, myxoid, atrophic, sclerosing or myoid lesion. Some of these subtypes may occur isolated or in association with one of the others creating hybrid lesions. We present the case of a 66 years old woman having a 4 cm diameter tumor located on the abdominal wall. Histopathological examination of the resection specimen revealed areas of typical DFSP associated with fibrosarcomatous transformation, myoid and myxoid areas. Also, focally, pleomorphic tumor cells and foreign-body type multinucleated giant cells were observed. Immunostains revealed CD34 positivity in typical DFSP and myxoid areas with negative staining of some of the tumor cells in fibrosarcomatous areas and negative staining of myoid areas. Smooth muscle actin was positive in myoid areas. The nature of myoid fascicles in DFSP is a matter of debate, being uncertain whether these represent a type of tumor differentiation or a reactive myoid proliferation. In this particular case, finding the association of myoid cells with blood vessel walls sustains their reactive nature. We present the morphological aspects of the different areas of the tumor with emphasis on differential diagnostic problems and clinical implications.

Problems of Differential Diagnosis in Melanoma Arising from Blue Naevus.

Melanoma arising from blue naevus is an exceedingly rare variant of melanoma. Most of the cases are located in head and neck area, with scalp the most affected site. This type of melanoma develops on blue naevus or resembles blue naevus, most frequently cellular blue naevus. We present the case of a 52 years old female diagnosed with a pigmented melanoma of the scalp, with maximum tumoral thickness of 6.8 mm and invasion of the hypodermis, highly resembling cellular blue naevus. All criteria of malignancy were present: prominent nuclear pleomorphism, infiltrative pattern, tumoral necrosis, high mitotic rate (11 mitoses/mm2) with atypical mitosis and high Ki67 index. No lymph node or distant metastases were identified at presentation. Because of the rarity of cases, histopathological diagnosis can be difficult, differential diagnosis with blue naevi, atypical blue naevi or metastatic melanoma being the most challenging problems. Prognosis is given by tumoral thickness, frequently being more than 4 mm.

A review of morphological aspects in dermatofibrosarcoma protuberans with clinicopathological correlations.

Dermatofibrosarcoma protuberans represents a rare malignant neoplasm involving the skin affecting all ages, frequently young adults. It is characterized by high rates of local recurrences after surgery and rare distant metastasis. Clinically it may present as a non-protuberant or a protuberant lesion, having a relative non-specific aspect mimicking a scar, morphea, a benign cyst or other skin tumor. Several clinicopathologic subtypes of dermatofibrosarcoma protuberans have been described: fibrosarcomatous, pigmented, juvenile, myxoid, atrophic, sclerosing and myoid. Among these, the fibrosarcomatous variant stands out as the most aggressive subtype with higher risk of local recurrences and metastasis. All clinicopathologic variants have in common a characteristic microscopic pattern of infiltration into subcutaneous fat. However, this may be present on small areas or unavailable for examination on biopsy fragments. For this reason, the awareness of this variable morphology is essential for establishing a correct diagnosis and performing an optimal treatment.

The influence of Helicobacter pylori presence on the immunophenotype of inflammatory infiltrate in gastric diseases.

The first medical hypothesis about the possible relationship between chronic inflammatory response and carcinogenesis belongs to Virchow and it was published in 1893. In these days, multiple studies demonstrate the certain involvement of chronic inflammation as trigger of progression towards malignancy. The fact that in 1994, the International Agency for Research on Cancer considered Helicobacter pylori as first class carcinogenic agent, is postulating the existence of the pathogenical chain carcinogenesis, of chronic inflammatory lesions as it was described by Correa, as a first step. Our study including 75 patients who underwent surgical procedures for gastric lesions uses immunohistochemical studies for lymphocytes phenotyping, to identify the nature of inflammatory cells involved, correlating the results with the presence of Helicobacter pylori. We tried to bring new information needed for establish to what extent the chronic inflammation of gastric mucosa is a response to the presence of bacteria and is implicated in tumorigenesis. We used T cells antibodies: CD3, CD4, CD5, CD8, CD57, GranzymeB and B cells antibodies: Cd20 and CD23. Our results revealed the presence of immune cellular response to Helicobacter pylori in gastric mucosa, based on T helper, cytotoxic and NK cells. B cells have a minor role in this response. CD4+ cells seem to be involved in local protection response as well as in carcinogenesis, while CD8+ have a minor or no role in carcinogenesis.

Carcinogenesis and infection with Helicobacter pylori.

It was accepted several years ago that, in the carcinogenesis process of human cancers, biologic agents, especially the viruses, are playing an etiologic role. This is the case of lymphomas (retroviruses), hepatocarcinoma (hepatic viruses) and cervical carcinoma (papilloma viruses). Helicobacter pylori is the first bacteria recognized as a first class carcinogen for gastric cancer. Nevertheless, comparing with the most validated human carcinogens, the activity of H. pylori is very little studied. As a consequence, at this moment, in its case, explanation of carcinogenesis mechanism is more or less hypothetical.