2 research outputs found
Generalized Virasoro anomaly and stress tensor for dilaton coupled theories
We derive the anomalous transformation law of the quantum stress tensor for a
2D massless scalar field coupled to an external dilaton. This provides a
generalization of the Virasoro anomaly which turns out to be consistent with
the trace anomaly. We apply it together with the equivalence principle to
compute the expectation values of the covariant quantum stress tensor on a
curved background. Finally we briefly illustrate how to evaluate vacuum
polarization and Hawking radiation effects from these results.Comment: enlarged version of hep-th/0307096 containing the quantum stress
tensor for arbitrary geometries and discussion of the Hawking effect. To
appear in Phys. Lett.
Male breast cancer
Male breast cancer (MBC) is a rare disease representing less than 1% of all breast cancers (BC) and less than 1% of cancers in men. Age at presentation is mostly in the late 60s. MBC is recognized as an estrogen-driven disease, specifically related to hyperestrogenism. About 20% of MBC patients have family history for BC. Mutations in BRCA1 and, predominantly, BRCA2, account for approximately 10% of MBC cases.
Because of its rarity, MBC is often compared with female BC (FBC). Based on age-frequency distribution, age-specific incidence rate patterns and prognostic factors profiles, MBC is considered similar to late-onset, postmenopausal estrogen/progesterone receptor positive (ER+/PR+) FBC. However, clinical and pathological characteristics of MBC do not exactly overlap FBC. Compared with FBC, MBC has been reported to occur later in life, present at a higher stage, and display lower histologic grade, with a higher proportion of ER+ and PR+ tumors.
Although rare, MBC remains a substantial cause for morbidity and mortality in men, probably because of its occurrence in advanced age and delayed diagnosis. Diagnosis and treatment of MBC generally is similar to that of FBC. Men tend to be treated with mastectomy rather than breast-conserving surgery. The backbone of adjuvant therapy or palliative treatment for advanced disease is endocrine, mostly tamoxifen.
Use of FBC-based therapy led to the observation that treatment outcomes for MBC are worse and that survival rates for MBC do not improve like FBC. These different outcomes may suggest a non-appropriate utilization of treatments and that different underlying pathogenetic mechanisms may exist between male and female BC