2005

LGL Tan, YY Tan, D Heng, MY Chan
Correspondence: Dr Patrick M Y Chan, Patrick_Chan@ttsh.com.sg

ABSTRACT
Introduction The presence of axillary lymph node metastases is an important prognostic factor in breast cancer. Sentinel lymph node biopsy (SLNB) is an emerging method for the staging of the axilla. It is hoped that with SLNB, the morbidity from axillary lymph node dissection (ALND) can be avoided without compromising the staging and management of early breast cancer. However, only patients found to be SLNB negative benefit from this procedure, as those with positive SLNB may still require ALND. Our objective is to study the various clinico-pathological factors to find predictive factors for axillary lymph node involvement in early breast cancer. It is hoped that with these factors, we will be better able to identify groups of patients most likely to benefit from SLNB.
Methods A retrospective study of 380 early breast cancer cases (stage T1 and T2, N0, N1, M0) in women treated in the Department of General Surgery, Tan Tock Seng Hospital, between January 1999 and August 2002, was conducted. Incidence of nodal metastases was correlated with clinico-pathological factors, and analysed by univariate and multivariate analyses.
Results Approximately 35 percent of the 380 cases of early breast cancer had nodal metastases. Multivariate analyses revealed four independent predictors of node positivity: tumour size (p-value equals 0.0001), presence of lymphovascular invasion (p-value is less than 0.0001), tumours with histology other than invasive ductal or lobular carcinoma (p-value equals 0.04), and presence of progesterone receptors (p-value equals 0.05).
Conclusion We have found independent preoperative predictive factors in our local population for the presence of nodal metastases. This information can aid patient selection for SLNB and improve patient counselling.

Keywords: axillary lymph node, breast cancer, node dissection, sentinel lymph node biopsy
Singapore Med J 2005; 46(12): 693-697

S Namwongprom, S Boonyaprapa, M Ekmahachai, N Vilasdechanon, A Somwangprasert, S Sumitsawan, P Taya
Correspondence: Dr Sirianong Namwangprom, snamwong@mail.med.cmu.ac.th; sirinam@chiangmai.ac.th

ABSTRACT
Introduction To analyse and determine the clinical value of lymphoscintigraphy for sentinel lymph node (SLN) localisation in woman undergoing surgery for breast cancer, and evaluate the predictive value of SLN versus axillary lymph node (ALN) status in these patients.
Methods Preoperative breast lymphoscintigraphy was performed in 35 female patients with breast cancer and clinically-negative ALNs. The mean age was 52.8 years (age range 38 to 73 years). The lymphoscintigraphy was performed using 74 MBq of Tc-99m nanocolloid subdermal injection over the tumour. The SLN location was marked on the skin. All patients underwent standard modified radical mastectomy with axillary lymph node dissection (ALND). A comparison of SLN and ALN histopathological results was completed in order to define the means by which the SLN biopsy was able to reflect the final status of ALNs.
Results In 20/35 (57.1 percent) cases, SLNs were visualised in 20-minute dynamic imaging. In 12 patients, SLNs were seen after delayed imaging and/or by repositioning the patient. Overall, the estimated SLN identification rate was 91.4 percent. Of 32 patients in whom SLNs were localised by lymphoscintigraphy, nine were positive for metastatic tumours and the rest were negative for tumour involvement. In four of these nine patients, SLN was the only node that contained metastatic tumour cells while in five patients, an additional concomitant ALN metastasis was detected. In four patients, SLN was negative on frozen section, but skip ALN metastases were noted. Of three patients in which SLNs were not localised by lymphoscintigraphy, two had positive ALNs for tumour cells and the remaining one was negative for tumour involvement.
Conclusion We concluded that SLN localisation using lymphoscintigraphy is an accurate minimally-invasive procedure for staging breast cancer patients with clinically-negative ALNs, and can substantially reduce the morbidity and costs of surgical treatment by avoiding unnecessary ALND in the majority of patients.

Keywords: axillary lymph node, breast cancer, lymphoscintigraphy, preoperative breast lymphoscintigraphy, sentinel lymph node localisation
Singapore Med J 2005; 46(12): 688-692

S Twaddle
Correspondence: Dr Sara Twaddle, sara.twaddle@nhs.net

ABSTRACT
This paper introduces the concepts of evidence-based clinical practice guidelines. It describes the key elements of guideline development, using examples from the Scottish Intercollegiate Guidelines Network (SIGN), and then goes on to discuss how practitioners in Singapore and other countries can find and use guidelines from other areas of the world. It concludes with a short section on the future direction of guideline development.

Singapore Med J 2005; 46(12): 681-687

HC Chew, SH Lim
Correspondence: Dr Chew Huck Chin, chinnjing@pacific.net.sg

ABSTRACT
A 25-year-old man presented at the emergency department with complaints of fever and chest pain. The electrocardiogram (ECG) showed concave ST segment elevation that was not confined to any arterial territory. There was PR segment elevation in lead aVR as well as PR segment depression in leads II, V5 and V6. This was consistent with pericarditis. The electrocardiographical changes associated with pericarditis are discussed. A second case of a 64-year-old man with uraemic pericarditis with similar ECG changes is illustrated.

Keywords: electrocardiographical changes, pericarditis, ST elevation, uraemic pericarditis
Singapore Med J 2005; 46(11): 656-660

ATYE, SL Lam
Correspondence: Dr S L Lam, lamsl@kkh.com.sg

ABSTRACT
Live twin ectopic gestations are extremely rare. There are more than 100 reported twin tubal pregnancies but less than ten have foetal cardiac motions demonstrated in both embryos. We describe an additional patient with live twin ectopic gestation. A 32-year-old woman presented with increasing left-sided abdominal pains. She had a high beta-hCG level and a significant history of subfertility with previous surgical intervention. Transvaginal ultrasonography showed viable left tubal twin ectopic pregnancy. The diagnosis was confirmed at surgery. Factors that contribute to the risk of ectopic pregnancy, diagnosis and the management of this condition are described.

Keywords: adnexal tubal ring, foetal heart beat, live twin ectopic pregnancy, subfertility, transvaginal ultrasonography
Singapore Med J 2005; 46(11): 651-655