Developing microsatellite markers for Geodorum eulophioides (Orchidaceae) and cross-species amplification in two sympatric,congeneric species

Geodorum (Orchidaceae) has approximately ten species, and is mainly distributed in tropical Asia. Among them, Geodorum eulophioides Schltr. is of major conservation concern as it has only four known populations, two each found in China and others in Burma. In this study, we developed 18 polymorphic microsatellites markers in G. eulophioides with the number of alleles ranging from two to 17. The expected and observed heterozygosities ranged from 0.046 to 0.918 and from 0.048 to 1.0000, respectively. The cross-species amplification rates for the sympatric G. recurvum (Roxb.) Alston and G. densiflorum (Lam.) Schltr. were 100 and 83.33 %, respectively. These markers developed would be useful for conservation and population genetic studies.     

Impact of positive surgical margins and their locations after radical prostatectomy: comparison of biochemical recurrence according to risk stratification and surgical modality

Purpose

We investigated the influence of positive surgical margins (PSMs) and their locations on biochemical recurrence (BCR) according to risk stratification and surgical modality.

Methods

A total of 1,874 post-radical-prostatectomy (RP) patients of pT2–T3a between 2000 and 2010 at three tertiary centers, and who did not receive neoadjuvant/adjuvant therapy, were included in this study. Patients were stratified according to BCR risk: low risk (PSA <10, pT2a-b, and pGS ≤6), intermediate risk (PSA 10–20 and/or pT2c and/or pGS 7), and high risk (PSA >20 or pT3a or pGS 8–10). The median follow-up was 43 months.

Results

PSMs were a significant predictor of BCR in both the intermediate- and high-risk-disease groups (P = .001, HR 2.1, 95 % CI 1.3–3.4; P < .001, HR 2.8, 95 % CI 2.0–4.1). Positive apical margin was a significant risk factor for BCR in high-risk disease (P = .003, HR 2.0, 95 % CI 1.2–3.3), but not in intermediate-risk disease (P = .06, HR 1.7, 95 % CI 0.9–3.1). Positive bladder neck margin was a significant risk factor for BCR in both intermediate- and high-risk disease (P < .001, HR 5.4, 95 % CI 2.1–13.8; P = .001, HR 4.5, 95 % CI 1.8–11.4). In subgroup analyses, robotic RP provided comparable BCR-free survival regardless of risk stratification. Patients with PSMs showed similar BCR-free survival between open and robotic RP (log-rank, P = .897).

Conclusions

Post-RP PSMs were a significantly independent predictor of disease progression in high-risk disease as well as intermediate-risk disease. Both positive apical and bladder neck margins are also significant risk factors of BCR in high-risk disease. Patients with PSMs showed similar BCR-free survival between open and robotic surgery.