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Shelley Hwang

Publications and source records attributed to Shelley Hwang.

5 recordsLinked to original sources
PubMed2005

The effect of sentinel node tumor burden on non-sentinel node status and recurrence rates in breast cancer.

BACKGROUND: Routine axillary lymph node dissection (ALND) after selective sentinel lymphadenectomy (SSL) in the treatment of breast cancer remains controversial. We sought to determine the need for routine ALND by exploring the relationship between sentinel lymph node (SLN) and non-SLN (NSLN) status. We also report our experience with disease relapse in the era of SSL and attempt to correlate this with SLN tumor burden. METHODS: This was a retrospective study of 390 patients with invasive breast cancer treated at a single institution who underwent successful SSL from November 1997 to November 2002. RESULTS: Of the 390 patients, 115 received both SSL and ALND. The percentage of additional positive NSLNs in the SLN-positive group (34.2%) was significantly higher than in the SLN-negative group (5.1%; P = .0004). The SLN macrometastasis group had a significantly higher rate of positive NSLNs (39.7%) compared with the SLN-negative group (5.1%; P = .0001). Sixteen patients developed recurrences during follow-up, including 6.1% of SLN-positive and 3.3% of SLN-negative patients. Among the SLN macrometastasis group, 8.7% had recurrence, compared with 2.2% of SLN micrometastases over a median follow-up period of 31.1 months. One regional failure developed out of 38 SLN-positive patients who did not undergo ALND. CONCLUSIONS: ALND is recommended for patients with SLN macrometastasis because of a significantly higher incidence of positive NSLNs. Higher recurrence rates are also seen in these patients. However, the role of routine ALND in patients with a low SLN tumor burden remains to be further determined by prospective randomized trials.

Adult↗
PubMed2005

Array-based comparative genomic hybridization from formalin-fixed, paraffin-embedded breast tumors.

Identification of prognostic and predictive genomic markers requires long-term clinical follow-up of patients. Extraction of high-quality DNA from archived formalin-fixed, paraffin-embedded material is essential for such studies. Of particular importance is a robust reproducible method of whole genome amplification for small tissue samples. This is especially true for high-resolution analytical approaches because different genomic regions and sequences may amplify differentially. We have tested a number of protocols for DNA amplification for array-based comparative genomic hybridization (CGH), in which relative copy number of the entire genome is measured at 1 to 2 mb resolution. Both random-primed amplification and degenerate oligonucleotide-primed amplification approaches were tested using varying amounts of fresh and paraffin-extracted normal and breast tumor input DNAs. We found that random-primed amplification was clearly superior to degenerate oligonucleotide-primed amplification for array-based CGH. The best quality and reproducibility strongly depended on accurate determination of the amount of input DNA using a quantitative polymerase chain reaction-based method. Reproducible and high-quality results were attained using 50 ng of input DNA, and some samples yielded quality results with as little as 5 ng input DNA. We conclude that random-primed amplification of DNA isolated from paraffin sections is a robust and reproducible approach for array-based CGH analysis of archival tumor samples.

Breast Neoplasms↗
PubMedDate not supplied

Primary tumor characteristics predict sentinel lymph node macrometastasis in breast cancer.

Selective sentinel lymphadenectomy (SSL) is rapidly becoming the standard of care in the surgical management of patients with early breast cancer. Sentinel lymph node macrometastasis has been well documented in the literature to have a higher risk of nonsentinel node tumor involvement when compared to micrometastasis. The aim of our study was to determine the primary tumor characteristics associated with sentinel node macrometastasis that will allow us to preoperatively determine this subgroup of patients at risk. This study was a retrospective review of 644 patients who underwent successful SSL as part of their surgical treatment of breast cancer at the University of California San Francisco Carol Franc Buck Breast Care Center from November 1997 to August 2003. All patients underwent preoperative lymphoscintigraphy followed by wide excision or mastectomy and sentinel lymphadenectomy with or without axillary lymph node dissection. One hundred twenty-two patients had positive sentinel nodes on histology. Micrometastasis was present in 43 of these patients and macrometastasis in the remaining 79. Statistical analysis showed that a tumor size greater than 15 mm, poor tubule formation by the tumor cells, and lymphovascular invasion were significantly associated with sentinel node macrometastasis. A high mitotic count showed a trend but was not significant in our study. Patients with a tumor size greater than 15 mm, poor tubule formation, and lymphovascular invasion are at risk of having sentinel node macrometastasis. These patients can be identified preoperatively based on imaging and biopsy criteria, allowing the option of selective intraoperative pathologic evaluation of the sentinel node and immediate completion axillary dissection as necessary.

Adult↗
PubMedDate not supplied

Ratio of positive to total number of sentinel nodes predicts nonsentinel node status in breast cancer patients.

Selective sentinel lymphadenectomy (SSL) has replaced axillary lymph node dissection (ALND) for many patients with early breast cancer and negative sentinel lymph nodes (SLNs). Yet many patients with a positive SLN are undergoing unnecessary ALND, as no further disease is found in the axilla. The aim of our study was to determine factors associated with additional positive lymph nodes in the axilla in patients who have a positive SLN. This was a retrospective study of patients undergoing SSL with ALND as part of their treatment for breast cancer at a single institution from November 1997 to August 2003. Only patients with one or more positive SLNs were selected for this study. There were 86 patients who fit our study criteria. Of these, 38% had further positive lymph nodes upon ALND. More than one positive SLN and a ratio of positive SLNs to total SLNs of greater than 0.5 were found to be predictors for additional axillary nodal involvement in both univariate and multivariate analyses. The number of positive SLNs and the ratio of positive SLNs to total SLNs is an indication of total tumor burden in the sentinel nodes and may be a reflection of the propensity of the tumor for further lymphatic invasion in the axillary basin.

Adult↗