Immunostaining for the tumour suppressor gene p16 product is a useful marker to differentiate melanoma metastasis from lymph-node nevus

Upon the introduction of extensive sampling protocols of sentinel node biopsies, pathologists are increasingly confronted with small melanoma metastases. Using conventional histology, it proves sometimes difficult or impossible to differentiate small melanoma metastases from lymph-node nevi. Loss of the tumour suppressor gene p16 has been shown to be associated with tumour progression of melanoma. We investigated nevus and melanoma cells for the presence of the product of the gene p16, using immunohistochemistry. All nevus cells, independent of their location (nodal or skin) displayed an extensive nuclear and cytoplasmic staining for p16. In contrast, all cells of melanoma metastases, except one skin metastasis, lacked nuclear staining for p16. These findings indicate that p16 is a reliable marker to distinguish lymph-node nevi from melanoma metastasi

Hypoxia and Ezrin Expression in Primary Melanoma Have High Prognostic Relevance

Hypoxia affects tumor aggressiveness and activates pathways associated with epithelial mesenchymal transition (EMT) which are crucial for tumor progress. In this study, the correlation of hypoxia and EMT with sentinel lymph node status and tumor-specific survival was investigated in primary melanomas. CD34 for capillary count and Hypoxia inducible factor-1α (HIF-1α) as hypoxia indicators as well as Ezrin and L1-Cell Adhesion Molecule (L1CAM), both critical proteins contributing to EMT, were analyzed using immunohistochemistry in 49 melanoma patients with long follow-up (F/U, mean 110 months; range 12-263 months). We found a significant correlation between Breslow tumor thickness and Ezrin expression (p = 0.018). L1CAM expression in primary melanoma was significantly associated with HIF-1α expression (p < 0.0001) and sentinel lymph node metastasis (p = 0.011). Furthermore, low capillary count, reflecting hypoxic condition, was significantly associated with Ezrin expression (p = 0.047) and decreased tumor-specific survival (p = 0.035). In addition, patients with high Ezrin expression in their primary melanoma had a dramatic loss of life early in their F/U period (mean survival time 29 months; range 15-44 month). Our results highlight the relevance of Ezrin, L1CAM and HIF-1α as prognostic markers in melanoma patients. Additionally, we demonstrate that hypoxia in primary melanoma affects EMT and is at least partly responsible for early metastatic dissemination

Multiple bilateral asymmetrical deficiency of trunk muscles

Trunk muscles are an important source for pedicled and free flaps in reconstructive surgery. Unilateral deficiencies of trunk muscles are well known, either isolated or as part of Poland's syndrome. Bilateral muscular deficiencies and a "bilateral Poland anomaly” have also been sporadically reported, but this is rare. We report on an 82-year-old male cadaver with clinically obscure, asymmetric bilateral deficiencies of the majority of trunk muscles. There was a history of acute poliomyelitis in childhood. Histological examination of representative muscle samples of the trunk showed extensive muscle atrophy with fat and connective tissue replacement. This was compatible with the prior diagnosis of poliomyelitis. However, representative sections of the spinal cord failed to reveal the antecedent poliomyelitis. The possibility of subclinical bilateral deficiencies of trunk muscles has to be taken into account in patients with a history of poliomyelitis when planning reconstructions in cases of regional pedicled muscle transfers or free microvascular tissue transfers in reconstructive surger

Fibrin versus polyethylene glycol sealant: an experimental study in rabbits

Fibrin glue has been applied universally in general surgery as an adhesive, hemostatic, or embolizing agent. In reconstructive surgery, fibrin has been used mainly for nerve and microvascular repair or as a substitute for sutures in skin closure and skin grafting. Another area of increasing use is in face-lift surgery, where the goal is to improve hemostasis on the raw surfaces and to discourage the occurrence of major hematomas. However, as most components of the fibrin glue are derived from human or bovine plasma, they may cause allergic reactions and transmit infectious agents such as hepatitis or AIDS virus, or prions such as the Creutzfeldt-Jakob disease agent. With these risks in mind, we tested polyethylene glycol (PEG) sealant, a recently introduced and purely synthetic vascular sealant, as an alternative to fibrin glue. A 2 × 2cm subcutaneous pocket was created on the dorsal thighs of ten New Zealand White rabbits by an incision medial to the sciatic vein. The pockets were randomly filled with either 0.2ml of thawed fibrin glue or PEG sealant. After the operation, the thighs were inspected macroscopically for hematoma, seroma, or granuloma formation. Eleven weeks later, the animals were killed, and the fibrin and polyethylene glycol-filled pockets were harvested en bloc with the overlying skin and processed for histological examination. A swelling, viewed macroscopically, was visible at the experimental site in three thighs of the fibrin group, but in none of the PEG group. Only two specimens of the fibrin group and five specimens of the PEG group showed no signs of inflammation. All other specimens revealed signs of chronic or granulomatous inflammation, with no significant difference between the groups. This experimental study showed that 11weeks after application of either fibrin or PEG sealant, signs of chronic or even granulomatous inflammation were detectable in 2/3 of the specimens in the fibrin group and in approximately 50% of the specimens in the PEG group. Beyond the comparable potential of both sealants to induce inflammatory tissue reactions, PEG sealant has some notable advantages as it is purely synthetic and therefore carries no risk of transmission of viral pathogens or prions. The combination of this safety profile, the ease of application, and the consistently good reported hemostatic results obtained with PEG sealant makes it an interesting alternative to fibrin glue in plastic surger

Rare Choristoma of the Tarsal Conjunctiva: Critical Inspection Prevents Unnecessary Mutilation

We report a case of a 26-year-old male patient with an incidental finding of a flesh-colored tumor with few vellus hairs on its surface, located on the fornix and the tarsal conjunctiva of the left lower eyelid. Histology of the biopsy showed a choristoma consisting of abundant vellus hairs, sebaceous glands, and sparse lacrimal gland tissue. Recognition of conjunctival vellus hairs is significant and raises the suspected diagnosis of choristoma, which can be confirmed by a small sample biopsy. A complete excision is unnecessary and possible surgical complications can be prevented. Choristomas of the tarsal conjunctiva are very rare and, to our knowledge, this is the first histological documentation of a choristoma containing vellus hair located on the tarsal conjunctiva. In addition, we review the histopathological findings of choristomas and their differential diagnoses. Keywords: Case report; Choristoma; Hamartoma; Tarsal choristoma; Vellus hai

Single cell polarity in liquid phase facilitates tumour metastasis

Dynamic polarisation of tumour cells is essential for metastasis. While the role of polarisation during dedifferentiation and migration is well established, polarisation of metastasising tumour cells during phases of detachment has not been investigated. Here we identify and characterise a type of polarisation maintained by single cells in liquid phase termed single-cell (sc) polarity and investigate its role during metastasis. We demonstrate that sc polarity is an inherent feature of cells from different tumour entities that is observed in circulating tumour cells in patients. Functionally, we propose that the sc pole is directly involved in early attachment, thereby affecting adhesion, transmigration and metastasis. In vivo, the metastatic capacity of cell lines correlates with the extent of sc polarisation. By manipulating sc polarity regulators and by generic depolarisation, we show that sc polarity prior to migration affects transmigration and metastasis in vitro and in vivo

Detecting BRAF Mutations in Formalin-Fixed Melanoma: Experiences with Two State-of-the-Art Techniques

BACKGROUND: Melanoma is characterized by a high frequency of BRAF mutations. It is unknown if the BRAF mutation status has any predictive value for therapeutic approaches such as angiogenesis inhibition. PATIENTS AND METHODS: We used 2 methods to analyze the BRAF mutation status in 52 of 62 melanoma patients. Method 1 (mutation-specific real-time PCR) specifically detects the most frequent BRAF mutations, V600E and V600K. Method 2 (denaturing gel gradient electrophoresis and direct sequencing) identifies any mutations affecting exons 11 and 15. RESULTS: Eighteen BRAF mutations and 15 wild-type mutations were identified with both methods. One tumor had a double mutation (GAA) in codon 600. Results of 3 samples were discrepant. Additional mutations (V600M, K601E) were detected using method 2. Sixteen DNA samples were analyzable with either method 1 or method 2. There was a significant association between BRAF V600E mutation and survival. CONCLUSION: Standardized tissue fixation protocols are needed to optimize BRAF mutation analysis in melanoma. For melanoma treatment decisions, the availability of a fast and reliable BRAF V600E screening method may be sufficient. If other BRAF mutations in exons 11 and 15 are found to be of predictive value, a combination of the 2 methods would be useful

Expression of MAGE-C1/CT7 and MAGE-C2/CT10 Predicts Lymph Node Metastasis in Melanoma Patients

MAGE-C1/CT7 and MAGE-C2/CT10 are members of the large MAGE family of cancer-testis (CT) antigens. CT antigens are promising targets for immunotherapy in cancer because their expression is restricted to cancer and germ line cells and a proportion of cancer patients presents with immune responses against CT antigens, which clearly demonstrates their immunogenicity. This study investigates the expression of MAGE-C1/CT7 and MAGE-C2/CT10 in primary and metastatic melanoma. Immunohistochemical staining of tissue microarrays that consisted of 59 primary malignant melanomas of the skin, 163 lymph node and distant melanoma metastases and 68 melanoma cell lines was performed. We found MAGE-C1/CT7 expression in 15 out of 50 (24%) primary melanomas and 15 out of 50 (24%) cell lines, whereas MAGE-C2/CT10 was detected in 17 out of 51 (33%) primary melanomas and 14 out of 68 (17%) cell lines. MAGE-C1/CT7 and MAGE-C2/CT10 were both detected in 40% of melanoma metastases. Patients with MAGE-C1/CT7 or MAGE-C2/CT10 positive primary melanoma had significantly more lymph node metastases (p = 0.005 and p<0.001, resp.). Prediction of lymph node metastasis by MAGE-C1/CT7 and MAGE-C2/CT10 was independent of tumor cell proliferation rate (Ki67 labeling index) in a multivariate analysis (p = 0.01). Our results suggest that the expression of MAGE-C1/CT7 and MAGE-C2/CT10 in primary melanoma is a potent predictor of sentinel lymph node metastasis