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Gary J Whitman

Publications and source records attributed to Gary J Whitman.

31 records · Page 2Linked to original sources

Neoadjuvant chemotherapy for breast carcinoma: multidisciplinary considerations of benefits and risks.

BACKGROUND: The majority of patients with breast carcinoma receive chemotherapy as a component of multimodality treatment. Over the past decade, it has become increasingly more common to deliver chemotherapy first, but this has raised new questions within all disciplines of cancer management. METHODS: The authors reviewed published studies on the effect of neoadjuvant chemotherapy for breast carcinoma on the practice of medical oncology, surgical oncology, radiation oncology, pathology, and radiology. RESULTS: Treating breast carcinoma with neoadjuvant chemotherapy has several advantages, such as providing the earliest possible treatment against preexisting micrometastases, offering selected patients breast conservation therapy, and allowing for measurement of disease response, which can then be used to customize subsequent chemotherapy. However, neoadjuvant chemotherapy affects the practice not only of medical oncology, but also has important implications for the specialties of surgery, radiology, pathology, and radiation oncology. The current review addressed the new opportunities and challenges within the multidisciplinary care of breast carcinoma provided by neoadjuvant chemotherapy. CONCLUSIONS: The complexity of the issues led the authors to conclude that patients who receive neoadjuvant chemotherapy are likely to benefit from a coordinated multidisciplinary approach to their care.

Breast Neoplasms↗

Intraoperative margin assessment reduces reexcision rates in patients with ductal carcinoma in situ treated with breast-conserving surgery.

BACKGROUND: Reported rates of reexcision for margin control after breast-conserving surgery for ductal carcinoma in situ (DCIS) range from 48% to 59%. The optimal technique for intraoperative margin assessment in patients with DCIS has yet to be defined. We sought to determine whether intraoperative multidisciplinary evaluation using gross tissue assessment and sectioned-specimen radiography reduces the need for reoperation for margin control in DCIS. METHODS: A prospectively compiled database was used to identify patients who had DCIS diagnosed by core needle biopsy and were treated with breast-conserving surgery at our institution between July 1999 and July 2002. All patients had intraoperative gross margin assessment and specimen radiography of both the whole and sliced specimen for calcifications. RESULTS: Four hundred two patients with DCIS were evaluated at our institution during the study period. Of these, 160 had excisional biopsy for diagnosis prior to referral, 92 had mastectomy as their initial procedure, 40 were seen for a second opinion only, and 1 patient refused surgery. The remaining 109 patients formed the study population. The median age was 55 years (range 34 to 81). The median pathologic size of DCIS was 1.2 cm (range 0.2 to 8.0 cm). Fifty-nine patients had positive (less than 1 mm) or close (less than 5 mm) margins on intraoperative assessment. Final pathology agreed with intraoperative assessment of a positive or close margin in 43 of the 59 patients (P = 0.00005). Seventy-five percent of those thought to have a positive or close margin at the time of surgery (n = 44) underwent intraoperative reexcision. Of the total 109 patients, 31 (34%) had an intraoperative reexcision that resulted in a change in margin status from positive on intraoperative evaluation to negative on final pathologic evaluation (P < 0.00001). A second procedure for margin control was necessary in only 24 patients (22%). The decision to excise additional tissue at the first surgery on the basis of intraoperative assessment resulted in significantly fewer second procedures for margin control (P = 0.029). CONCLUSIONS: In patients with DCIS, intraoperative margin assessment by gross pathological examination and sliced specimen radiography significantly affects intraoperative decision making, and excision of further tissue on the basis of intraoperative assessment results in a substantial decrease in second procedures for margin control.

Adult↗

Atypical ductal hyperplasia diagnosis by directional vacuum-assisted stereotactic biopsy of breast microcalcifications. Considerations for surgical excision.

In 824 patients who underwent directional vacuum-assisted biopsies (DVABs) of breast microcalcifications, 61 (7.4%) showed atypical ductal hyperplasia (ADH). The 42 who subsequently underwent excision were the subjects of this study. Cases were evaluated for the mammographic characteristics of the lesion, the percentage of lesion removed according to mammography, and histologic findings (including number of large ducts and/or terminal duct-lobular units involved with ADH) in DVAB specimens. Pathologic findings in the surgical specimens in the area of the biopsy site also were recorded. In the DVAB specimens, ADH was confined to an average of 1.5 large ducts or lobular units and was associated with microcalcifications in all of the patients. Surgical specimens showed ADH in 15 cases, no residual lesion in 24 cases, and ductal carcinoma in situ in 3 cases. We found that microcalcifications that contain ADH in less than 3 lobules or ducts and/or that are removed completely by DVAB do not reveal higher-risk lesions on excision; thus, removal is unnecessary. When assessing microcalcifications with ADH, clinicians should consider the percentage of microcalcifications removed by DVAB and the extent of lobular involvement to better assess the need for excision.

Adult↗

Pseudoangiomatous stromal hyperplasia of the breast.

Pseudoangiomatous stromal hyperplasia is a benign proliferative lesion of the mammary stroma that rarely presents as a localized mass. We describe the clinical, radiologic, cytologic, and histologic features of a case of pseudoangiomatous stromal hyperplasia that presented as a rapidly growing breast lesion in a 36-year-old woman.

Adult↗

A dual-energy subtraction technique for microcalcification imaging in digital mammography--a signal-to-noise analysis.

Breast cancer may manifest as microcalcifications (microCs) in x-ray mammography. However, the detection and visualization of microCs are often obscured by the overlapping tissue structures. The dual-energy subtraction imaging technique offers an alternative approach for imaging and visualizing microCs. With this technique, separate high- and low-energy images are acquired and their differences are used to "cancel" out the background tissue structures. However, the subtraction process could increase the statistical noise level relative to the calcification contrast. Therefore, a key issue with the dual-energy subtraction imaging technique is to weigh the benefit of removing the cluttered background tissue structure over the drawback of reduced signal-to-noise ratio in the subtracted microC images. In this report, a theoretical framework for calculating the (quantum) noise in the subtraction images is developed and the numerical computations are described. We estimate the noise levels in the dual-energy subtraction signals under various imaging conditions, including the x-ray spectra, microC size, tissue composition, and breast thickness. The selection of imaging parameters is optimized to evaluate the feasibility of using a dual-energy subtraction technique for the improved detection and visualization of microCs. We present the results and discuss its dependence on imaging parameters.

Breast↗

Microcalcification detectability for four mammographic detectors: flat-panel, CCD, CR, and screen/film).

Amorphous silicon/cesium iodide (a-Si:H/CsI:Tl) flat-panel (FP)-based full-field digital mammography systems have recently become commercially available for clinical use. Some investigations on physical properties and imaging characteristics of these types of detectors have been conducted and reported. In this perception study, a phantom containing simulated microcalcifications (microCs) of various sizes was imaged with four detector systems: a FP system, a small field-of-view charge coupled device (CCD) system, a high resolution computed radiography (CR) system, and a conventional mammography screen/film (SF) system. The images were reviewed by mammographers as well as nonradiologist participants. Scores reflecting confidence ratings were given and recorded for each detection task. The results were used to determine the average confidence-rating scores for the four imaging systems. Receiver operating characteristics (ROC) analysis was also performed to evaluate and compare the overall detection accuracy for the four detector systems. For calcifications of 125-140 microm in size, the FP system was found to have the best performance with the highest confidence-rating scores and the greatest detection accuracy (Az = 0.9) in the ROC analysis. The SF system was ranked second while the CCD system outperformed the CR system. The p values obtained by applying a Student t-test to the results of the ROC analysis indicate that the differences between any two systems are statistically significant (p<0.005). Differences in microC detectability for the large (150-160 microm) and small (112-125 microm) size microC groups showed a wider range of p values (not all p values are smaller than 0.005, ranging from 0.6 to <0.001) compared to the p values obtained for the medium (125-140 microm) size microC group. Using the p values to assess the statistical significance, the use of the average confidence-rating scores was not as significant as the use of the ROC analysis p value for p value.

Breast Neoplasms↗

Dual-energy digital subtraction chest radiography: technical considerations.

In the evaluation of asbestos-related pulmonary and pleural abnormalities, conventional chest radiography has been shown to have a low sensitivity for the detection of lung nodules and subtle interstitial disease. Pleural plaques may simulate pulmonary nodules, and interstitial processes can be masked by adjacent pleural abnormalities. Dual-energy digital subtraction chest radiography may enable investigators to characterize asbestos-related pulmonary and pleural abnormalities with greater accuracy. "Soft-tissue" images, designed to remove pleural calcifications, may allow for better evaluation of the lung parenchyma. "Bone" images, designed to remove soft-tissue structures, may enhance the detection of pleural calcifications. In this pictorial essay we illustrate the methods, technical considerations, and limitations of dual-energy digital subtraction chest radiography performed with global subtraction weighting factors.

Adult↗