Sentinel lymph node biopsy after percutaneous diagnosis of nonpalpable breast cancer.

PURPOSE: To determine the technical success rate of sentinel lymph node biopsy in women with nonpalpable infiltrating breast cancer diagnosed by using percutaneous core biopsy and to determine the frequency with which sentinel lymph node biopsy obviated axillary dissection. MATERIALS AND METHODS: Retrospective review revealed 33 women who underwent sentinel node biopsy after percutaneous core biopsy diagnosis of nonpalpable infiltrating breast cancer. Sentinel nodes were identified with radioisotope and blue dye; the procedure was technically successful if sentinel nodes were found at surgery. All sentinel nodes were excised. Axillary dissection was performed if tumor was present in sentinel nodes. RESULTS: Sentinel nodes were found at surgery in 30 women (91%). Sentinel nodes were identified with both radioisotope and blue dye in 22 (73%) of these women, with only radioisotope in six (20%), and with only blue dye in two (7%). Sentinel nodes were found in 12 (80%) of 15 women in the first half of the study versus all 18 (100%) women in the second half (P = .08). Sentinel nodes were free of tumor in 23 (77%) of 30 women. In six (86%) of seven women with tumor in sentinel nodes, the sentinel nodes were the only nodes with tumor. CONCLUSION: Sentinel node biopsy was successful in 30 women (91%) with nonpalpable infiltrating carcinoma diagnosed with percutaneous core biopsy and obviated axillary dissection in 23 women (70%). Using both radioisotope and blue dye may increase the success rate. A learning curve exists, and success improves with experience.     

Sentinel node biopsy in male breast cancer

OBJECTIVE: Male breast cancer is a rare disease and axillary status is the most important prognostic indicator. Lymphoscintigraphy associated with gamma-probe guided surgery has been proved to reliably detect sentinel nodes in female patients with breast cancer. This study evaluates the feasibility of the surgical identification of sentinel node by using lymphoscintigraphy and a gamma-detecting probe in male patients, in order to select subjects who would be suitable for complete axillary lymphadenectomy. METHODS: Colloid human albumin labelled with 99Tc was administered to 18 male patients with breast cancer and clinically negative axillary lymph nodes. Lymphoscintigraphy was performed the day before surgery. An intraoperative gamma-detecting probe was used to identify sentinel nodes during surgery. RESULTS: Lymphoscintigraphy and biopsy of the sentinel node were successful in all cases. A total of 20 sentinel nodes were removed. Pathological examinations showed 11 infiltrating ductal carcinomas, two intraductal carcinomas and five intracystic papillary carcinomas. Six patients (33%) had positive sentinel node (micrometastases were found in three patients). These patients underwent axillary dissection; in five of them (83%) the sentinel node was the only positive node. Twelve patients (67%) showed negative sentinel nodes; in all of them no further surgical treatments were planned. CONCLUSIONS: As in women, lymphoscintigraphy and sentinel node biopsy under the guidance of a gamma-detecting probe proved to be an easy method for the detection of sentinel nodes in male breast carcinoma. In male patients with early stage cancer, sentinel node biopsy might represent the standard surgical procedure in order to avoid unnecessary morbidity after surgery, preserving accurate staging of the disease in the axilla.     

Nonpalpable breast lesions: diagnosis with slightly overpenetrated screen-film mammography and hook wire-directed biopsy in 1,014 cases

Slightly overpenetrated screen-film mammography and hook wire-directed localization were used in 1,014 breast biopsies performed for nonpalpable, mammographically detected breast abnormalities. One lymphoma and 205 breast cancers (20%) were found; 115 breast cancers (56%) were noninvasive, and 90 (44%) were invasive. Mastectomy was performed in 69 breast cancers (34%); 136 (66%) were treated conservatively, 28 with biopsy only and 108 with lumpectomy, node dissection, and radiation therapy. All patients with noninvasive breast cancers treated with axillary dissection had uninvolved lymph nodes. Of the 90 invasive breast cancers, six (7%) had metastases to axillary nodes, which, to the authors' knowledge, is lower than percentages reported in other studies of wire-directed breast biopsies. The authors believe that the slightly overpenetrated technique is a valuable adjunct to screen-film mammography.     

MR imaging-guided axillary node biopsy for breast cancer: initial findings

The aim of this study was to evaluate the usefulness and feasibility of preoperative sentinel node needle biopsy of the breast under guidance of open MR imaging, a method that we developed. Nine patients with breast cancer in whom the axillary lymph nodes were not palpable underwent preoperative sentinel node needle biopsy under real-time MR imaging guidance. The sentinel nodes were identified before the biopsy using CT and MR imaging. Diagnostic ability of this method was compared with that of the operative diagnosis. Sentinel nodes were correctly identified in all 9 patients. The MR imaging-guided sentinel node needle biopsy was performed for all of the 9 patients, and, in 7 (77.8%) of the 9, a specimen sufficient for pathologic evaluation was obtained; and in 6, whether malignancy existed was precisely diagnosed. No serious complications were noted. This experience indicates the possibility of a precise diagnosis of whether the sentinel node in breast cancer is benign or malignant without surgery.     

Biopsy of sentinel lymph nodes guided by lymphoscintigraphic mapping in patients with breast cancer

OBJECTIVE. The purpose of this study was to determine the technical success rate of sentinel node biopsy with lymphoscintigraphy in women with breast cancer and the frequency with which sentinel node biopsy obviated axillary dissection. Factors affecting the success rate of sentinel node biopsy and lymphoscintigraphy were also evaluated. MATERIALS AND METHODS. Retrospective review revealed 119 women with breast cancer who underwent lymphoscintigraphy and sentinel node biopsy at our institution during the study period. A planned axillary dissection was performed in 13 of the first 16 patients; otherwise, axillary dissection was only performed if tumor was present in sentinel nodes or if the sentinel node biopsy was unsuccessful. RESULTS. Sentinel node biopsy was successful in 96% of patients, and sentinel node metastases were found in 20%. In 78% of patients, a negative sentinel node biopsy obviated axillary dissection. Prior excisional biopsy was not associated with a failed sentinel node biopsy (p = 0.750) but was associated with failed lymphoscintigraphy (p = 0.01). Successful lymphoscintigraphy was associated with successful sentinel node biopsy (p < 0.0001). No association was found between the histology or size of the tumor and a failed sentinel node biopsy (p = 0.46 and p = 0.1, respectively) or failed lymphoscintigraphy (p = 0.36 and p = 0.47, respectively). CONCLUSION. Sentinel node biopsy guided by lymphoscintigraphy, intraoperative gamma probe, and isosulfan blue dye is an effective alternative to axillary dissection in patients with breast cancer. Lymphoscintigraphy improved the success rate of sentinel node biopsy. Large tumor size or prior excisional biopsy should not prevent patients from having sentinel node biopsy.     

Radioguided sentinel lymph node biopsy in breast cancer surgery.

The concept of sentinel lymph node biopsy in breast cancer surgery relates to the fact that the tumor drains in a logical way through the lymphatic system, from the first to upper levels. Therefore, the first lymph node met (the sentinel node) will most likely be the first to be affected by metastasis, and a negative sentinel node makes it highly unlikely that other nodes are affected. Because axillary node dissection does not improve prognosis of patients with breast cancer (being important only to stage the axilla), sentinel lymph node biopsy might replace complete axillary dissection to stage the axilla in clinically N0 patients. Sentinel lymph node biopsy would represent a significant advantage as a minimally invasive procedure, considering that, after surgery, about 70% of patients are found to be free from metastatic disease, yet axillary node dissection can lead to significant morbidity. Furthermore, histologic sampling errors can be reduced if a single (sentinel) node is assessed extensively rather than few histologic sections in a high number of lymph nodes per patient. Although the pattern of lymph drainage from breast cancer can be variable, the mammary gland and the overlying skin can be considered as a biologic unit in which lymphatics tend to follow the vasculature. Therefore, considering that tumor lymphatics are disorganized and relatively ineffective, subdermal and peritumoral injection of small aliquots of radiotracer is preferred to intratumoral administration. (99m)Tc-labeled colloids with most of the particles in the 100- to 200-nm size range would be ideal for radioguided sentinel node biopsy in breast cancer. Lymphoscintigraphy is an essential part of radioguided sentinel lymph node biopsy because images are used to direct the surgeon to the site of the node. The sentinel lymph node should have a significantly higher count than that of background (at least 10:1 intraoperatively). After removal of the sentinel node, the axilla must be reexamined to ensure that all radioactive sites are identified and removed for analysis. The sentinel lymph node should be processed for intraoperative frozen section examination in its entirety, based on conventional histopathology and, when needed, immune staining with anticytokeratin antibody. The success rate of radioguidance in localizing the sentinel lymph node in breast cancer surgery is about 94%--97% in institutions where a high number of procedures are performed and approaches 99% when combined with the vital blue dye technique. At present, there is no definite evidence that negative sentinel lymph node biopsy is invariably correlated with negative axillary status, except perhaps for T1a-b breast cancers, with a size of < or =1 cm. Randomized clinical trials should elucidate the impact of avoiding axillary node dissection on patients with a negative sentinel lymph node on the long-term clinical outcome of patients.     

淋巴显像及术中γ探测定位活检乳腺癌前哨淋巴结

目的：探讨淋巴显像及术中γ探测定位活组织检查乳腺癌前硝淋巴结的临床价值。方法：术前在乳腺肿瘤表面正中皮内注射37－74MBq ^99Tcm-大分子右旋糖酐（Dx)，用淋巴显像和术中γ探测定位乳腺癌 前硝淋巴结，术中切除前 淋巴结，而后行腑窝淋巴结清扫术，两标本连同切除的乳腺肿物同时送病理检查，分析和前哨淋巴结转移与腋窝淋巴结的关系。结果：31例均行淋巴显像和术中γ探测定位乳腺癌前哨淋巴结患者中，检出率为100％，有3例前哨淋巴结病理检查呈假阴性，假阴性率为25％，结论：术中γ探测是乳腺癌前哨淋巴结定位最可靠的手段。以乳腺 癌前哨淋巴结活组织检查取代常规腑窝淋巴结清扫术尚需进一步研究。     

乳癌哨兵淋巴结检测临床应用

目的：探讨乳癌哨兵淋巴结活检预测腋窝淋巴结转移状态的可靠性.方法：本组为2000年11月至2004年2月我院收治的140例乳癌患者.术中应用国产亚甲蓝注射液4～6 ml肿瘤上、外、下半圆形皮下连续注射,134例行乳癌改良根治术或患侧乳腺区段切除加腋窝淋巴结清扫术.术后解剖蓝染淋巴管,沿着色淋巴管找到蓝染的哨兵淋巴结.哨兵淋巴结及腋窝淋巴结常规行石蜡病理切片检查.5例行乳腺区段切除加哨兵淋巴结活检,1例行全乳切除加哨兵淋巴结活检（冰冻、石蜡病理检查SLN转移阴性）,未行全腋窝淋巴结清扫.结果：140例患者中136例检出哨兵淋巴结,检出率97.14%,灵敏度 88.71%,准确率94.31%,阴性预测值89.71%,假阴性率11.29%,仅哨兵淋巴结阳性7例.结论：应用亚甲蓝注射液淋巴结着色方法行乳癌哨兵淋巴结活检可以准确地预测腋窝淋巴结转移状态.     

Nonvisualization of axillary sentinel node during lymphoscintigraphy: is there a pathologic significance in breast cancer?

The aim of this study was to define the factors associated with nonvisualization of a sentinel node (SN) in the axilla area during preoperative lymphoscintigraphy. METHODS: We retrospectively studied 332 women with T0, T1, or T2 <3-cm, N0 invasive breast cancer who underwent a sentinel lymph node biopsy procedure. All patients had intradermal and intraparenchymal injection of 37 MBq (99m)Tc-sulfur colloid in a total volume of 4 x 0.1 mL, above and around the tumor. Anterior and lateral static views were obtained a few minutes and 2-4 h after injection. Surgery was performed the next day. The SNs were localized intraoperatively with the aid of patent blue dye and using a hand-held gamma-probe. SNs were analyzed by serial sections stained with hematoxylin-eosin, with the adjacent section stained with anticytokeratin antibodies. Different parameters, such as the number of positive lymph nodes, presence of lymphovascular invasion, tumor size, tumor grade, histology (invasive vs. in situ), prior excisional biopsy, and patient age were analyzed to determine whether they had any significant correlation with nonvisualization of SNs in the axillary area. RESULTS: An axillary SN was successfully visualized on the preoperative lymphoscintigraphy in 302 of 332 patients (90.7%). No axillary drainage was found in 30 patients on the delayed images, even after a second injection of radiocolloid, and 5 of 30 patients showed uptake outside the axillary area. Positive nodes were identified in 86 of 302 patients (28.5%) with successful axillary drainage and in 19 of 30 patients (63.3%) with unsuccessful axillary drainage. More than 4 invaded axillary nodes (P < 0.0001) and the presence of lymphovascular invasion in the breast tumor (P = 0.004) were the only significant variables on univariate analysis, although multivariate analysis showed that only the increased number of invaded nodes was statistically significant. CONCLUSION: Patients with unsuccessful axillary mapping have an increased risk for axillary involvement.     

Factors affecting sentinel node localization during preoperative breast lymphoscintigraphy.

Variable success rates for identifying axillary (AX) sentinel nodes in breast cancer patients using preoperative lymphoscintigraphy have been reported. We evaluated the effects of age, weight, breast size, method of biopsy, interval after biopsy, and imaging view on the success of sentinel node identification and on the kinetics of radiopharmaceutical migration. METHODS: Preoperative breast lymphoscintigraphy was performed in consecutive breast cancer patients from February 1998 to December 1998. The ipsilateral shoulder was elevated on a foam wedge and the arm was abducted and elevated overhead. Imaging using this modified oblique view of the axilla (MOVA) started immediately after peritumoral injection of Millipore-filtered 99mTc-sulfur colloid and continued until AX sentinel nodes were identified. Anterior views were obtained after MOVA. AX, internal mammary (IM), and clavicular (CL) basins were monitored in all patients. MOVA was compared with the anterior view for sentinel node identification. Age, weight, breast size, method of biopsy, interval after biopsy, and primary tumor location were evaluated for their effects on sentinel node localization and transit times from injection to arrival at the sentinel nodes. RESULTS: Seventy-six lymphoscintigrams were obtained for 75 patients. AX sentinel nodes were revealed in 75 (99%) cases. IM or CL sentinel nodes were found in 19 (25%) cases and were not related to tumor location; exclusive IM drainage was present in 1 (1%) case. Identification of AX sentinel nodes was equivalent with MOVA and anterior views in 18 (24%) patients, was better with MOVA in 20 (26%) patients, and was accomplished only with MOVA in 38 (50%) patients. Median transit time was 17.5 min (range, 1 min to 18 h) after injection, and larger breast size was associated with increased transit time. No effect of age, weight, biopsy method, interval from biopsy, or tumor location on transit time was found. CONCLUSION: Use of MOVA can improve identification of AX sentinel nodes. Although AX drainage is the predominant pattern, a tumor in any portion of the breast can drain to IM sentinel nodes. Transit time was influenced by breast size. Overall short arrival times with this technique allow sentinel lymph node dissection to be performed on the same day as lymphoscintigraphy.     

Sentinel lymphoscintigraphy in patients with breast cancer undergoing excisional biopsy

Some small tumors of the breast cannot be diagnosed by needle biopsy, and an excisional biopsy is occasionally needed for the diagnosis. Sentinel node navigation surgery is frequently suitable for patients with such small breast cancers. The purpose of this study was to compare sentinel lymphoscintigrams in breast cancer patients who had previously undergone excisional biopsy with sentinel lymphoscintigrams in patients undergoing no excisional biopsy. We also investigated the possibility of clinical application of the sentinel node navigation procedure in the former group of patients. METHODS: Sentinel lymphoscintigrams of 43 patients with breast cancer undergoing excisional biopsy were compared to those of 116 patients without excisional biopsy. Lymphoscintigrams were obtained by using intradermal and/or subdermal injections of technetium-99m labeled phytate at 2 points on each side of the dermal incision in patients after excisional biopsy. Injections were performed at 2 points of the skin over the tumor in the patients who had not undergone excisional biopsy. RESULTS: Axillary lymph nodes were visualized in 42 of 43 patients undergoing excisional biopsy (98%) and in 115 of 116 patients without excisional biopsy (99%). The number of visualized axillary nodes was 1 to 5 (mean +/- SD = 2.1 +/- 1.0) and 1 to 5 (mean +/- SD = 1.9 +/- 1.0) in the two groups, respectively. No significant difference was determined between the two groups. Parasternal lymph nodes were depicted in 3 patients after excisional biopsy who had the tumor in the outer half of the breast, in contrast to 4 without excisional biopsy who had the tumor in the inner half. Intramammary hot spots were observed in 5 patients after excisional biopsy and in 2 without excisional biopsy. Lymphatic vessels were observed in 23 patients (53%) who had the excisional biopsy, and in 37 (32%) who did not have the biopsy. The former figure was significantly higher than the latter (p < 0.02). CONCLUSION: Sentinel node navigation surgery for axillary nodes was shown to be possible in patients undergoing excisional biopsy. However, the visualization of parasternal nodes, intramammary hot spots and lymphatic vessels tended to increase in number, and care must be exercised in the management of these patients.     

MR imaging--guided large-core (14-gauge) needle biopsy of small lesions visible at breast MR imaging alone.

PURPOSE: To report our experience with magnetic resonance (MR) imaging-guided large-core breast biopsy of lesions visible at breast MR imaging only. MATERIALS AND METHODS: Stereotactic large-core (14-gauge) needle biopsy of 78 lesions visible at MR imaging only was performed with MR imaging guidance in 59 patients. Results were validated with excisional biopsy or mastectomy in 42 lesions and with radiologic-pathologic correlation and/or follow-up MR imaging for at least 2 years in another 17 lesions. The accuracy of MR imaging--guided core biopsy was determined for those 59 lesions with established validation. The effect on patient treatment was evaluated by comparing the prebiopsy treatment plan with the ultimate treatment. RESULTS: Histologic diagnosis from core biopsy was possible in 77 (99%) of 78 lesions. In the 59 lesions with established validation, the diagnostic accuracy of MR imaging--guided core biopsy was 98% (58 of 59). Successful MR imaging--guided core biopsy findings changed treatment in 70% (54 of 77) of lesions. Difficulties were due to the unsatisfactory performance of earlier types of MR imaging--compatible biopsy guns and decreasing target visibility during intervention. CONCLUSION: MR imaging--guided large-core stereotactic breast biopsy is sufficiently accurate for obtaining histologic proof of lesions visible only at MR imaging. It can change patient treatment by reducing unnecessary surgical biopsy and can enable one-step surgery for breast cancers.     

Stereotactic and ultrasound-guided breast biopsy

Percutaneous imaging-guided needle biopsy has increasingly become an alternative to surgical biopsy for the histologic assessment of breast lesions. Percutaneous biopsy is faster, less invasive, and less expensive than surgical biopsy. Tissue acquisition is performed with automated core needles or directional vacuum-assisted biopsy probes. Guidance for percutaneous biopsy is usually provided by stereotaxis, ultrasound, and, more recently, under the guidance of MR imaging. Imaging guidance depends on lesion type and the results of diagnostic imaging studies. This article reviews indications, advantages, limitations, and controversial issues in percutaneous imaging-guided biopsy of breast lesions under stereotactic and ultrasound guidance. The potential for new research opportunities and directions is also discussed.     

Significance of preoperative lymphoscintigraphy and thin-slice computed tomography on sentinel node assessment: metastatic sentinel node in a lateral paramammary lesion out of axillary nodes from breast cancer

Sentinel node status was evaluated using preoperative lymphoscintigraphy in a 43-year-old woman who presented with an invasive ductal carcinoma in the lower outer quadrant of the right breast. Two strong hot nodules were visualized in the affected axillary basin on an early image, and a faint accumulation of radioactive tracer was lying between the cancer in the right lower outer quadrant and the axillary hot nodules on the lymphoscintigram taken at 90 min. The faint accumulation was considered to represent a small paramammary node on thin-slice computed tomography (CT) and was confirmed by node biopsy to be a sentinel node grossly involved with tumor cells. Immediate axillary dissection and adjuvant chemotherapy was subsequently performed. Careful evaluation using lymphoscintigraphy and thin-slice CT may be associated with increased localization of true sentinel nodes.     

Clinical axillary recurrence after sentinel node biopsy in breast cancer: a follow-up study of 220 patients

Purpose The aim of this study was to evaluate the frequency of false-negative (FN) sentinel node procedures in patients with breast cancer and the subsequent clinical outcome in such patients.Methods A total of 325 breast cancer patients underwent sentinel lymph node biopsy at our institution between June 1998 and May 2004. A 2-day protocol was used to localise the sentinel node with the injection of ^99mTc-nanocolloid. There were two phases in the study: the learning phase (105 patients) and the application phase (220 patients). In the learning phase, a complete lymphadenectomy was always performed. In the application phase, sentinel nodes were studied intraoperatively and lymphadenectomy was performed when considered warranted by the pathological intraoperative results.Results The median follow-up duration in the 220 patients studied during the application phase was 21.2 months (range 4–45 months). In this phase a total of 427 sentinel nodes were obtained (range 1–5 per patient, median 1.99), with 66 positive sentinel nodes in 56 patients (26%). The lymphadenectomies performed were also positive in 25% of cases (14 patients). We observed a total of two false-negative sentinel lymph node results (3.45%). One of them was found during the surgical excision of non-sentinel nodes, and the other presented as an axillary recurrence 17 months postoperatively (1.72% clinical false-negative rate). The latter patient died 1 year after the first recurrence.Conclusion After a median follow-up of 21.2 months we observed only one clinical recurrence among 220 patients. Our results indicate that adequate local control is achieved by application of the sentinel node protocol.     

Impact of internal mammary sentinel node imaging in breast cancer

A 28-year-old woman underwent mammary lymphoscintigraphy for evaluation of the sentinel node status of a small infiltrating ductal carcinoma in the central, lower, and outer quadrant of the left breast confirmed by biopsy. The patient was scheduled for lumpectomy and sentinel node biopsy. Lymphoscintigraphy showed increased uptake at two sites of the peritumorally injected tracer (60 MBq; 1.6 mCi rhenium sulfur nanocolloid) in internal mammary nodes, two of which were located most proximal to the tumor and related to the tumor by two distinct lymphatic ducts. An axillary lymph node was also detected. At surgery, the gamma probe confirmed the location of all the hot spots, and four nodes were harvested: one axillary, two first internal mammary nodes in the third intercostal space, and one internal mammary node in the second intercostal space. Histologic analysis revealed that the axillary sentinel node was free of disease, but the two first intramuscular sentinel nodes were metastatic. The second-echelon internal mammary node above the sentinel nodes (second intercostal space) was free of disease. This case shows the benefit of imaging all the drainage pathways of a breast tumor and retrieving nonaxillary lymph nodes, which may be the only positive nodes. As a result of the findings, the patient's prognosis may be altered and the subsequent therapeutic approach may be modified. Although exclusive involvement of the internal mammary chain is well established and relatively rare (occurring in approximately 5% of cases), it is important to remember that the axillary status of a breast tumor is not the only major prognostic factor.     

Sentinel node localization in breast cancer. Periareolar injection of radiocolloid

Traditional lymphadenectomy is being replaced by sentinel node biopsy in initial management of early stage breast cancer. The aim of this study was to validate the technique in our center, where we perform preoperative lymphoscintigraphy and intraoperative detection of sentinel node, after periareolar radiotracer and peritumoral blue dye injection. Sixty patients, breast cancer stages I and II, were included. Lymphatic mapping was performed the day before surgery, after the administration of 74 MBq 99mTc sulfur colloid in periareolar subdermal tissue. Surgical detection of sentinel node through gamma probe was followed by intraoperative and occasionally delayed biopsies. Finally, full axillary node dissection was completed. Lymphoscintigraphy identified sentinel node in 78% of the patients (47/60): 43 in axilla, 4 in internal mammary chain. Probe guided axillary detection was achieved in 88% (53/60): in every patient with axillar migration in scan, in 9/13 without imaged drainage and in 1/4 with internal mammary chain migration. Sensitivity of blue dye technique was 75% (45/60), the concordance between both procedures being high. Considering both, the overall success rate of surgical detection was 90% (54/60); if we exclude those patients who showed exclusive extraaxillar drainage, the success rate reaches 95%. Malignancy was found in 24% of sentinel nodes removed (13/54); it being the only metastatic axillary node in 4/13. No false negative sentinel nodes were found. Therefore, negative predictive value and accuracy were 100%. These results allow us to validate the technique in our center.     

Sentinel node detection in pre-operative axillary staging

The concept of sentinel lymph node biopsy in breast cancer surgery is based on the fact that the tumour drains in a logical way via the lymphatic system, from the first to upper levels. Since axillary node dissection does not improve the prognosis of patients with breast cancer, sentinel lymph node biopsy might replace complete axillary dissection for staging of the axilla in clinically N0 patients. Sentinel lymph node biopsy would represent a significant advantage as a minimally invasive procedure, considering that about 70% of patients are found to be free from metastatic disease, yet axillary node dissection can lead to significant morbidity. Subdermal or peritumoural injection of small aliquots (and very low activity) of radiotracer is preferred to intratumoural administration, and (99m)Tc-labelled colloids with most of the particles in the 100-200 nm size range would be ideal for radioguided sentinel node biopsy in breast cancer. The success rate of radioguidance in localising the sentinel lymph node in breast cancer surgery is about 97% in institutions where a high number of procedures are performed, and the success rate of lymphoscintigraphy in sentinel node detection is about 100%. The sentinel lymph node should be processed for intraoperative frozen section examination in its entirety, based on conventional histopathology and, when necessary, immune staining with anti-cytokeratin antibody. Nowadays, lymphoscintigraphy is a useful procedure in patients with different clinical evidence of breast cancer.     

Identification of the sentinel node in patients with breast cancer

Sentinel node analysis represents a significant advance in the diagnosis and treatment of invasive breast cancer. The traditional crude method of full axillary dissection for assessing the status of the axillary nodes can now be discarded in favor of the much more elegant and modern approach of minimally invasive sentinel node analysis and its attendant elimination of the morbidity of traditional axillary node dissection. The many impediments to and pitfalls in the technique of sentinel node analysis, however, must be recognized and overcome for the procedure to be reliable and consistently successful. The use of ultrasound and a smaller particle size can help overcome many of these pitfalls. Because ultrasound identification of the axillary sentinel node in patients with invasive breast cancer is possible, it may allow for percutaneous excision of these nodes in the future (Fig. 8). Combining percutaneous excision and ablation of the primary breast carcinoma with percutaneous excision of the sentinel node allows for the nonsurgical treatment of small breast cancers in the future. The modern breast radiologist should be at the forefront of these advances.     

Palpable breast masses: is there a role for percutaneous imaging-guided core biopsy?

OBJECTIVE: The purpose of this study was to evaluate percutaneous imaging-guided core biopsy in the assessment of selected palpable breast masses. MATERIALS AND METHODS: Of 1388 consecutive breast lesions that had percutaneous imaging-guided core biopsy, 155 (11%) were palpable. Palpable masses referred for percutaneous imaging-guided core biopsy included lesions that were small, deep, mobile, vaguely palpable, or multiple. Biopsy guidance was sonography in 140 lesions (90%) and stereotaxis in 15 (10%). Surgical correlation or minimum of 2 years follow-up is available in 115 palpable masses in 107 women. Medical records, imaging studies, and histologic findings were reviewed. RESULTS: Of 115 palpable breast masses, 98 (85%) were referred by surgeons to the radiology department for percutaneous imaging-guided core biopsy and 88 (77%) had percutaneous imaging-guided core biopsy on the day of initial evaluation at our institution. Percutaneous imaging-guided core biopsy spared additional diagnostic tissue sampling in 79 (74%) of 107 women, including 57 women with carcinoma and 22 women with benign findings. Percutaneous imaging-guided core biopsy did not spare additional tissue sampling in 28 women (26%), including 15 women in whom surgical biopsy was recommended on the basis of percutaneous biopsy findings and 13 women with benign (n = 7) or malignant (n = 6) percutaneous biopsy findings who chose to undergo diagnostic surgical biopsy. CONCLUSION: Percutaneous imaging-guided core biopsy is useful in the evaluation of palpable breast masses that are small, deep, mobile, vaguely palpable, or multiple. In this study, percutaneous imaging-guided core biopsy spared additional diagnostic tissue sampling in 74% women with palpable breast masses.