Normal color variations of the canine ocular fundus, a retrospective study in Swedish dogs.

BACKGROUND: A retrospective study was made to demonstrate normal variations of the color and size of the tapetal area and color of the nontapetal area in the ocular fundus in dogs, correlating them to breed, age and coat color. METHODS: The study was based on protocols of five hundred and thirty-nine adult dogs describing eye examinations made during the years 1997-2001. The dogs were examined using an indirect ophthalmoscope in order to find heritable eye diseases. The following characteristics were recorded: breed; age; coat color; color and size of the tapetal area and color of the nontapetal area. Normal color variations in the fundus were studied and categorized with regard to breed, age and coat color. Chi-square analysis was used comparing distributions between factors. Differences between mean values were analysed with Student's t-test or one-way-ANOVA. A logistic regression analysis was performed on the color of the tapetal area with the color of the coat and breed. RESULTS: Twenty breeds were represented. The mean age was 42.8 months. The most common colors of the tapetal area were yellow-green and orange, and the most common colors of the nontapetal area were dark brown and black. The analysis revealed that coat-color and breed concomitantly did not significantly influence tapetal color. Brown coated dogs often had a striped red and brown nontapetal area. The color of the tapetal area influenced the color of the nontapetal area. Smaller-sized breeds (such as Papillon) had a smaller tapetal area. A tapetal area was completely absent in 1.9%. The age did not influence the color of the tapetal area. CONCLUSIONS: Color of the tapetal area was influenced by both coat color and breed, but neither of these was statistically more influential than the other. The color of the tapetal area influenced the color of the nontapetal area. The size of the tapetal area correlated to breed and to body size.

Primary ano-rectal malignant melanomas within a population-based national patient series in Sweden during 40 years.

PURPOSE: To analyze 251 patients (101 males and 150 females) diagnosed with ano-rectal malignant melanoma (ARMM) reported to the Swedish National Cancer Registry during 1960-1999. METHODS: Incidence, gender and age profiles, primary anatomical sites and density of the melanomas along with geographic distribution, and prognosis were investigated. RESULTS: The age-standardized incidence of ARMM was significantly higher for females (1.0 per 10(6) females) than for males (0.7 per 10(6) males) throughout the 40-year-period. The incidence increased with age peaking at 75-84 years in both genders. 54% of the tumours were primary in the anal canal, 24% engaged the whole ano-rectal unit and 10% were located at the anal verge (11% unknown primary site). Although ARMM were rare in absolute numbers, their density (number of tumours/square unit) was higher than that of cutaneous malignant melanomas (CMM) on average. No linkage between the geographic distribution of ARMM and population density was found. The prognosis was very poor albeit with a significant gender difference with a five-year survival rate of 10.6% for males and 15.7% for females. The survival rates for both genders improved during the 40-year-period but significantly more for females than males. CONCLUSION: The reason(s) for the difference in incidence and prognosis according to gender is unknown. The majority of ARMM emerged primary in the anal canal and a primary location exclusively in the colonic mucosa of the rectum is questionable. The higher density of ARMM as compared to the average density of CMM tallies with the result of our previous studies on vulvar melanoma and might be instrumental in exploring non-UV light associated factors in melanoma genesis. The concentration of patients with anal squamous cell carcinoma to population-dense urban areas, as previously reported, was not found in cases of ARMM.

Clinical significance of EGFR amplification and the aberrant EGFRvIII transcript in conventionally treated astrocytic gliomas.

The aim of this study was to evaluate the clinical value of assessing epidermal growth factor receptor (EGFR) amplification and the common 5' rearrangement of EGFR resulting in the EGFRvIII transcript in astrocytic gliomas. Data from 221 tumours were correlated with patient survival. The majority of previous studies evaluated amplification alone and provided contradictory results. Amplification was analysed by a densitometry of Southern blot analysis or quantitative polymerase chain reaction (PCR). EGFR transcripts were examined by reverse transcription PCR and subsequent sequencing. A ribonuclease (RNase) protection assay was carried out on a subgroup to confirm PCR results. Amplification of EGFR was found in 41% (65/160) of glioblastomas (GBs) and 10% (4/41) of anaplastic astrocytomas (AAs). The EGFRvIII rearrangement was identified in 54% (35/65) of GBs and 75% (3/4) of AAs with amplification, as well as in 8% (8/95) of GBs and 5% (2/37) of AAs without amplification (confirmed by RNase protection assay). There were no abnormalities of the EFGR or its transcript in grade II astrocytoma (AII). We found no significant association between EGFR amplification or rearrangement, and age or survival in the 160 GB patients. We noted a tendency towards decreased survival with any EGFR abnormality in the 41 patients with AAs. This was most marked in the five cases with the EGFRvIII transcript (p=0.069), but these were significantly older than those without (p=0.023). No abnormalities of EGFR were identified in AII patients. We conclude that neither EGFR amplification nor the presence of the EGFRvIII transcript predicts patient outcome in conventionally treated GBs. However, in AAs, although uncommon, EGFR aberrations appear to be associated with shorter survival.

Short postoperative survival for glioblastoma patients with a dysfunctional Rb1 pathway in combination with no wild-type PTEN.

PURPOSE: Glioblastoma (GB, WHO grade IV) is the most common primary brain tumor in adults. Survival is typically <1 year but varies between a few months and a couple of years. The aim of the study was to find novel genetic prognostic factors in a well-defined GB series. EXPERIMENTAL DESIGN: The survival data on 129 GBs were correlated with the results of a detailed analysis of 9 genes. These included 3 genes coding for proteins in the p53 pathway (i.e., TP53, p14(ARF), and MDM2), 4 in the Rb1 pathway (i.e., CDKN2A, CDKN2B, RB1, and CDK4), as well as PTEN and epidermal growth factor receptor. RESULTS: We found that abnormalities in any of the four genes (CDKN2A, CDKN2B, RB1, and CDK4) coding for components of the Rb1 pathway were associated with shorter survival (P = 0.002). In combination with loss of wild-type PTEN, the association was even stronger (P < 0.001), the median survival being 166 days as compared with the group without these abnormalities where the median postoperative survival was 437 days. The survival difference remained statistically significant in Cox' regression analysis adjusting for age (P = 0.012). CONCLUSIONS: The findings indicate that knowledge of the molecular genetic abnormalities in GBs provides important data in assessing individual patients. As additional advances in our understanding of the molecular genetics and cell biology of gliomas are made, in addition to providing prognostic information, such data may also provide targets for innovative therapy in the individual case.