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Biomedical subjects

Merlin R Hamre

Publications and source records attributed to Merlin R Hamre.

7 recordsLinked to original sources
PubMed2005

Bilateral risk for subsequent breast cancer after lobular carcinoma-in-situ: analysis of surveillance, epidemiology, and end results data.

PURPOSE: Noninvasive lesions involving the lobules of the breast are increasingly diagnosed as incidental microscopic findings at the time of lumpectomy or core-needle biopsy. We investigated the incidence rates of invasive breast cancer (IBC) after a diagnosis of lobular carcinoma-in-situ (LCIS) by using Surveillance, Epidemiology, and End Results (SEER) data. PATIENTS AND METHODS: Patients (N = 4,853) having a diagnosis of primary LCIS in the time period of 1973 to 1998 were identified using the SEER Public Use CD-ROM data. The database was then searched for patients with subsequent primary IBC occurrences (n = 350). The clinical and pathologic characteristics of patients with subsequent primary IBCs were compared with the characteristics of patients with primary IBCs attained during the same time period (N = 255,114). RESULTS: The incidence of IBC increased over time from diagnosis of LCIS, with 7.1% +/- 0.5% incidence of IBC at 10 years. IBCs detected after partial mastectomy occurred in either breast (46% ipsilateral and 54% contralateral); however, after mastectomy, most IBCs were contralateral (94.7%). IBCs occurring after LCIS more often represented invasive lobular histology (23.1%) compared with primary IBCs (6.5%). The standardized incidence ratio (the ratio of observed to expected cases) for developing IBC was 2.4 (95% CI, 2.1 to 2.6) adjusted for age and year of diagnosis. CONCLUSION: LCIS is associated with increased risk of subsequent invasive disease, with equal predisposition in either breast. The minimum risk of developing IBC after LCIS is 7.1% at 10 years.

Breast Neoplasms↗
PubMed2003

c-Kit expression in desmoid fibromatosis. Comparative immunohistochemical evaluation of two commercial antibodies.

To determine the frequency of c-Kit staining in desmoids and optimize an assay for clinical use, we stained 19 desmoids from various sites at various dilutions with 2 commonly used rabbit polyclonal, anti-c-Kit antibodies (A4502, DAKO, Carpinteria, CA; C-19, Santa Cruz Biotechnology, Santa Cruz, CA), with and without heat-induced epitope retrieval (HIER) in citrate buffer. Approdpriate external and internal control samples were evaluated for each test condition. At dilutions of 1:50 both antibodies stained substantial numbers of desmoids: with/without HIER, A4502, 89%/63%; C-19, 37%/74%. The staining was cytoplasmic without cell membrane accentuation. However, background stromal staining and nonspecific staining of endothelium and smooth and striated muscle were problematic with both antibodies at 1:50. At higher dilutions, C-19 stained no desmoid; however, diminished staining of external and internal control samples made it unreliable. A4502 similarly stained many fewer desmoids at higher dilutions. However, it retained strong staining of both external and internal control samples and showed much less nonspecific staining. Best results were achieved at 1:250 without HIER; only weak focal staining was present in 1 desmoid. With a simple immunohistochemical method optimized for clinical use, desmoid can be regarded as a c-Kit-negative tumor.

Animals↗
PubMed2003

Second malignant neoplasms after primary central nervous system malignancies of childhood and adolescence.

The standardized incidence ratios (SIR) and cumulative incidence rates were determined for developing second malignant neoplasms (SMNs) after primary central nervous system (CNS) malignancies occurring during childhood using registry data. A total of 4553 cases of primary CNS malignancies were identified. Forty-six cases developed SMNs, 19 occurring in a previously radiated field. The SIRs of developing second malignant neoplasms were 6.3 and 3.1 for those cases receiving and not receiving radiation therapy, respectively. The 20-year cumulative incidences for developing SMNs were 3.3 and 1.2% for cases receiving and not receiving radiation therapy, respectively. Children surviving CNS malignancies have an increased susceptibility for SMNs.

Adolescent↗
PubMed2002

Osteosarcoma as a second malignant neoplasm.

PURPOSE: The aim of this study is to compare primary and secondary osteosarcomas using data from the National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) program. METHODS: Osteosarcoma cases were identified in the SEER Cancer Incidence Public-Use Database, 1973-96 (1,511 primary and 133 secondary osteosarcomas). Secondary osteosarcomas were further classified as occurring within or outside the previously irradiated field. Comparisons among groups were performed by nominal logistic regression. Survival analyses were performed using Kaplan-Meir and proportional hazards regression. RESULTS: Secondary osteosarcomas were more likely to have a non-extremity primary site and an older age at diagnosis (>40 years) (<0.0001 for both). Secondary osteosarcoma cases continued to be more likely to have a non-extremity site when excluding those occurring within the radiation field. Five-year overall survival was 50% lower for secondary osteosarcomas for both extremity and non-extremity sites. Primary malignancies associated with secondary osteosarcomas included 14 lymphomas/leukemias, six sarcomas, 54 carcinomas, and seven other cancers. Secondary osteosarcomas occurring within a field of radiation were more likely to occur at a younger age, have a malignancy with a primary morphology other than carcinoma, a non-limb site, and a longer duration between their primary malignant neoplasms and the development of osteosarcoma. No difference in the overall survival was noted between secondary osteosarcomas occurring within an irradiated field and those that did not. CONCLUSIONS: Secondary osteosarcomas are associated with carcinomas especially in the elderly. Although a 50% decreased 5-year survival was observed for secondary osteosarcomas in this study, this might not reflect the current outcomes with more aggressive therapy.

Adolescent↗
PubMedDate not supplied

Cutaneous melanoma in childhood and adolescence.

Using population-based data from the Surveillance Epidemiology and End Results Program of the National Cancer Institute, melanoma occurring during childhood was evaluated. Compared to adult cases of melanoma, childhood cases had a higher proportion of females (61%) and non-Caucasians (6.5%). The incidence of melanoma increased 85% among 15- to 19-year-olds from 1973 to 1996. Incidence for 15- to 19-year-olds was higher in southern (23.9/million) than northern registries (14.5/million). Non-Caucasians had 3-30% of the cases expected compared to Caucasians. Overall survival of children/adolescents with melanoma was 89% and 79% at 5 and 20 years postdiagnosis, respectively. The majority of deaths were directly attributed to melanoma (72%).

Adolescent↗