Sentinel node staging in colon carcinoma: value of sentinel lymph node biopsy with radiocolloid and blue staining.

BACKGROUND: Nodal staging accuracy is important in the prognosis and selection of patients for chemotherapy. This prospective study aims to assess the feasibility and accuracy of the sentinel lymph node procedure (SNP) using radiocolloid and blue dye in colon carcinoma. METHODS: In 56 patients, lymphatic mapping was accomplished by means of intraoperatively injecting patent blue and nanocoll subserosally around the tumour. Sentinel nodes (SNs) were harvested ex-vivo. Nodes were stained with H&E. If lymph nodes were interpreted as negative for metastatic tumour, serial sectioning and immunohistochemical staining were performed. RESULTS: At least one SN was detected in 49 of 53 patients (92.5%). Three patients were excluded because of preoperatively detected metastases. Overall, 121 SN were harvested with a mean of 2.2 SN/patients. Eighteen patients had tumour positive nodes. In four patients, pathological nodes were palpable during operation and were excluded. The SN was histologically negative in 2 of 14 patients with positive nodes (false-negative rate 14.3%). In 5 of 14 patients with positive nodes, the SN was the exclusive site of regional nodal metastasis. Four patients were upstaged by immunohistochemical staining (28.6%). The negative predictive value was 93.9% and the overall accuracy 95.6%. Scintigraphy was done in 17 patients. In three patients the SN was detected only by this modality. DISCUSSION: The SN biopsy with the combined technique proved a feasible technique with a steep learning curve. It can change the initial staging from stage II to stage III colon carcinoma. Scintigraphy can improve the success rate of the technique.

Evaluation of pulmonary nodules: comparison of a prototype dual crystal (LSO/NAI) dual head coincidence camera and full ring positron emission tomography (PET).

PURPOSE: To determine the concordance of a prototype dual head coincidence camera (LSO-PS) and full ring PET (BGO-PET) using (18)F-fluorodeoxyglucose (FDG) in the evaluation of pulmonary nodules (PNs). MATERIALS AND METHODS: Patients referred for evaluation of < or =3 PNs (< or =3 cm diameter) were prospectively studied on the same day with both BGO-PET and LSO-PS. Imaging was performed at 60 and 120 min after injection of 370MBq FDG, respectively. Images were independently interpreted by four observers with each observer blinded to the other modality for the same patient. Lesions were scored in terms of relative intensity versus background. Non-attenuation corrected (nonAC) BGO-PET was used as the reference test. RESULTS: Forty-seven patients with 54 PNs (mean diameter 1.7 cm, S.D. 0.7) were included. Twelve nodules were in the < or =1.0 cm - 27 in the 1.1-2.0 cm - and 15 in the 2.1-3.0 cm range. Interobserver agreement was similar for both FDG imaging modalities. Using a sensitive assessment strategy with LSO-PS (> or = faint intensity deemed positive), there was a 97% (38/39, 95%CI 87-100%) concordance with BGO-PET and one false positive case with LSO-PS. Conservative reading (moderate or intense intensity deemed positive) resulted in a 92% (36/39, 95%CI 80-97%) concordance with BGO-PET, without false positives. The only lesion missed by LSO-PS using both assessment strategies involved a nodule 1.5 cm diameter that demonstrated moderate increased FDG uptake on BGO-PET. CONCLUSION: Depending on the test positivity criteria, LSO-PS demonstrates a high concordance (92-97%) with nonAC BGO-PET for the characterization of pulmonary nodules.

Proteus syndrome: a rare cause of hemihypertrophy and macrodactyly on bone scanning.

Proteus syndrome is a rare, sporadic genetic disorder characterized by overgrowth of multiple different tissues in a mosaic pattern. It is associated with connective tissue nevi, epidermal nevi, disproportionate overgrowth of multiple tissues, vascular malformations, characteristic tumors, and specific facial anomalies. Joseph Merrick, popularly known as the Elephant Man, is now believed to have suffered from Proteus syndrome. A case of Proteus syndrome and associated findings on bone scintigraphy are presented.

Sodium, blood pressure, and arterial distensibility in insulin-dependent diabetes mellitus.

We investigated 24-hour ambulatory blood pressure and arterial distensibility, a marker of biophysical vessel wall properties, in 32 normoalbuminuric type I diabetic patients and 32 healthy control subjects on diets containing 50 mmol and 200 mmol sodium per day. The increase in daytime diastolic blood pressure from 50 to 200 mmol sodium was significantly higher in the diabetic patients than in the control subjects (2.3+/-4.9 versus 0.2+/-3.7 mm Hg, P<.05). On a high sodium regimen, femoral artery distensibility was decreased in the diabetic patients compared with the control subjects (19.2+/-7.6 versus 24.1+/-9.3 10[-3]/kPa, P<.05). Angiotensin-converting enzyme inhibition in the diabetic patients on a high sodium diet decreased daytime diastolic blood pressure and increased femoral artery distensibility. The blood pressure decrease in response to angiotensin-converting enzyme inhibition correlated significantly with the blood pressure increase to sodium (for 24-hour systolic and diastolic blood pressure, r=.72, P<.001 and r=.76, P<.001). In addition, we found that in the diabetic patients on a high sodium diet, the renal blood flow response to exogenous angiotensin II was not bimodally distributed, as is the case in essential hypertension, in which a subgroup of the patients are characterized by sodium sensitivity of the blood pressure and an abnormal renal blood flow response to exogenous angiotensin II ("nonmodulator phenotype"). These results show that blood pressure in insulindependent diabetes mellitus is sodium sensitive, but that this is not related to the nonmodulator phenotype, and suggest that in IDDM a relatively high sodium intake may be a factor that predisposes to the development of diabetic vascular disease.

Technetium-99m-sestamibi/thallium-201 mismatch of thyroid and parathyroid adenoma in chronic renal failure.

We report on a patient who had chronic renal failure and relapse of secondary hyperparathyroidism after earlier extirpation of three glands. Whereas 201Tl-chloride uptake was absent in the thyroid and an ectopic parathyroid adenoma during routine subtraction 201Tl-99mTc scintigraphy, both glands could be visualized with 99mTc-sestamibi and [123I]sodium.

Radioimmunotherapy with intravenously administered 131I-labeled chimeric monoclonal antibody MOv18 in patients with ovarian cancer.

UNLABELLED: We investigated the safety and pharmacokinetics of (131)I-labeled chimeric monoclonal antibody MOv18 ((131)I-c-MOv18 IgG) in patients with ovarian cancer and the estimated radiation dose to cancer-free organs and tumor. METHODS: Three patients were injected intravenously with 3 GBq (131)I-c-MOv18. Toxicity was evaluated according to the World Health Organization toxicity scales. Blood sampling was performed for 12 wk after injection. Whole-body and SPECT imaging was performed frequently. Dose rates were obtained with a portable dose-rate measure. Quantitative activity analysis of several organs was performed with the region-of-interest technique. Absorbed doses were calculated using MIRDOSE3. RESULTS: Transient changes in hematologic profiles were seen in 2 patients. Pancytopenia developed in 1 patient; on analysis, she entered the study probably with exhausted bone marrow reserves. Nonhematologic toxicity was mild. No human antichimeric antibody responses were observed. Mean isolation time was 12 d. The plasma elimination half-life increased almost 3-fold compared with that after tracer doses of c-MOv18. Dosimetry showed mean absorbed doses of 163, 380, 276, 338, 781, and 216 cGy, for whole-body, liver, kidney, spleen, lung, and red marrow, respectively. Tumor-absorbed doses ranged from 600 to 3800 cGy. All patients achieved a stable disease state, as confirmed by CT and carcinoma-associated antigen CA 125, lasting from 2 to >6 mo. CONCLUSION: (131)I-labeled c-MOv18 can safely be given to patients with noncompromised bone marrow reserves and may have therapeutic potential particularly in patients with minimal residual disease.

Impact of lymphoscintigraphy on sentinel node identification with technetium-99m-colloidal albumin in breast cancer.

UNLABELLED: Identification of the sentinel node by using colloidal tracers and a gamma probe or lymphoscintigraphy could be an effective alternative for the complicated original dye-oriented approach. We studied the sentinel node detection rate using early and delayed imaging in breast cancer patients. METHODS: Thirty-seven patients were imaged 2 hr and 18 hr after peritumoral injection of 99mTc-colloidal albumin. Preoperatively, axillary foci were located with a handheld gamma probe that was also used to isolate radiolabeled nodes from the axillary dissection specimens. The predictive value of the sentinel node for the axillary tumorstatus was evaluated with histological examination. RESULTS: Two and 18 hr after injection, lymphoscintigraphy revealed one to three separate axillary lymph nodes in 33 and 34 patients, respectively. In 30 patients the axillary foci were easily localized with the gamma probe preoperatively. In all 34 patients (92%), with visualized axillary foci, at least one radioactive sample could be retrieved using the gamma probe (total 53 samples). Metastases were found in the sentinel nodes of 11 patients, in seven of 11 being the only tumor-positive lymph node in the axilla. There were no false-negative sentinel nodes. CONCLUSION: The selective targeting and prolonged intranodal retention of 99mTc-colloidal albumin allows successful sentinel node identification in most (92%) patients.

Comparison between the effects of amlodipine and lisinopril on proteinuria in nondiabetic renal failure: a double-blind, randomized prospective study.

Double-blind, randomized controlled studies of longer than 1 week in duration comparing the antiproteinuric potential of long-acting dihydropyridine calcium channel blockers with that of angiotensin converting enzyme (ACE) inhibitors are lacking. Therefore, we performed such a study in patients with nondiabetic renal disease and proteinuria. After a 4-week wash-out period in which patients did not use any medication known to affect proteinuria, 21 patients were randomized in a double-blind fashion to receive either the calcium channel blocker amlodipine (Amlo, 5 to 10 mg) or the ACE-inhibitor lisinopril (Lis, 5 to 10 mg). Throughout the 16-week study period, blood pressure, creatinine clearances, and proteinuria were measured every 2 weeks. In addition, device-measured blood pressure and renal hemodynamic studies were performed at the start and end of the study. Systolic blood pressure fell in the Lis group from 163+/-7 (SEM) to 140+/-8 mm Hg (P < .01) and from 157+/-10 to 147+/-6 mm Hg in the Amlo group; diastolic blood pressure fell from 101+/-3 to 86+/-7 mm Hg in the Lis group and from 98+/-3 to 91+/-2 mm Hg in the Amlo group. Renal hemodynamics were not affected by amlodipine treatment, whereas a fall in glomerular filtration rate (GFR) was seen in lisinopril-treated patients (from 55+/-11 to 50+/-10 mL/min; P < .01). Amlodipine did not significantly affect proteinuria. Lisinopril induced a decline in the protein-creatinine ratio with a maximal effect reached after 12 to 16 weeks of therapy (from 0.39+/-0.17 to 0.26 +/-0.11 g/mmol; P < .009). In conclusion, we could not demonstrate an antiproteinuric effect of the long-acting dihydropyridine calcium channel blocker amlodipine, whereas therapy with the ACE-inhibitor lisinopril resulted in a decrease in proteinuria. Amlodipine did not affect renal hemodynamics, whereas lisinopril induced a fall in GFR.

How morphometric analysis of metastatic load predicts the (un)usefulness of PET scanning: the case of lymph node staging in melanoma.

BACKGROUND: In primary cutaneous melanoma, the sentinel node (SN) biopsy is an accurate method for the staging of the lymph nodes. Positron emission tomography (PET) has been suggested as a useful alternative. However, the sensitivity of PET may be too low to detect SN metastases, which are often small. AIM: To predict the value of PET for initial lymph node staging in melanoma based on morphometric analysis of SN metastatic load, without exposing patients to PET. MATERIALS AND METHODS: In 59 SN positive patients with melanoma, the sizes of tumour deposits in the SNs and subsequent dissection specimens were measured by morphometry and correlated with the detection limits of current and future PET scanners. RESULTS: The median tumour volume within the basin was 0.15 mm(3) (range, 0.0001-118.86). Seventy per cent of these deposits were smaller than 1 mm(3). State of the art PET scanners that have a resolution of about 5 mm would detect only 15-49% of positive basins. Logistic regression analysis revealed no pretest indicators identifying patients expected to have a positive PET. However, the SN tumour load was a significant and single predictor of the presence of PET detectable residual tumour. CONCLUSION: Morphometric analysis of metastatic load predicts that PET scanning is unable to detect most metastatic deposits in sentinel lymph nodes of patients with melanoma because the metastases are often small. Therefore, the SN biopsy remains the preferred method for initial regional staging.

The implementation of the sentinel node biopsy as a routine procedure for patients with breast cancer.

BACKGROUND: The sentinel node procedure for breast cancer allows for accurate staging of the axilla while the axillary node dissection can be avoided in patients with no sentinel node metastasis. This study describes those patients in whom an axillary dissection is performed, depending on the outcome of the sentinel node procedure, with particular emphasis on the use of strict criteria for the procedure and its practical limitations. METHODS: Preoperative lymphoscintigraphy was performed in 115 consecutive patients. The sentinel nodes were located with the use of a gamma probe and blue dye. Axillary dissection was performed at the same time when the sentinel node procedure was positive by frozen section or not successful by the criteria used. RESULTS: The sentinel node procedure was successful in 106 patients, with the sentinel node being both radioactive and blue in 94% of these patients. The frozen section was positive in 21 of 37 patients with sentinel node metastases. Axillary dissection could be avoided in 69 patients. CONCLUSIONS: The triple technique (with the use of lymphoscintigraphy, the gamma probe, and the blue dye) gives a high success rate of the sentinel node procedure, even when strict criteria for a successful sentinel node procedure are used. Palpation of the open axilla for metastatic nonsentinel nodes is advocated.

Sentinel node detection in cervical cancer.

BACKGROUND: For superficial tumors such as melanoma, breast, and vulvar cancer, sentinel node detection prevents unnecessary extensive lymph node dissections. Sentinel node detection has not yet proved feasible in tumors, such as cervical cancer, that drain to deep pelvic lymph nodes. TECHNIQUE: We injected technetium-99m colloidal albumin around the tumor allowing preoperative lymphscintigraphy and intraoperative gamma probe detection of sentinel nodes. For visual detection, blue dye was injected at the start of surgery. EXPERIENCE: In six of 10 eligible women who had Wertheim-Meigs operations for cervical cancer stage Ib, one or more sentinel nodes could be detected by scintigraphy. Intraoperative gamma probe detection was successful in eight of ten women, whereas visual detection found sentinel nodes in only four. They were found as far as the common iliac level. One woman had positive lymph nodes, of which one was a sentinel node. CONCLUSION: Identification of sentinel nodes using radionuclide is possible in women with cervical cancer and potentially identifies women in whom lymph node dissection can be avoided.

Predictive factors for metastatic involvement of nonsentinel nodes in patients with breast cancer.

BACKGROUND: The potential morbidity of an axillary lymph node dissection in patients with breast cancer can be avoided in patients with a negative sentinel node (SN). HYPOTHESIS: It may be possible to identify a subset of patients with a positive SN and without metastases in the remaining axillary lymph nodes. DESIGN: Case-control study. SETTING: Both primary and referral hospital care. PATIENTS: Data were studied for 255 consecutive patients with stage T1 or T2 breast cancer who had a successful identification of the SN. INTERVENTIONS: In patients with a positive SN, histological examination of all non-SNs that were negative by routine examination was the same as that for SNs (multiple sectioning and immunohistochemical analysis). MAIN OUTCOME MEASURES: The incidence of non-SN metastases was correlated with the surface area and number of SN metastases and primary tumor characteristics. A micrometastasis was defined as less than 1 mm(2). RESULTS: Of 255 patients, the SN appeared to be positive in 93 (36%). Subsequent axillary lymph node dissection revealed positive non-SNs in 46 patients (49%). Patients with a single positive SN and patients with metastases less than 1 mm(2) in the SN had significantly less non-SN involvement than patients with more than 1 positive SN (40% vs. 78%) and patients with macrometastases (27% vs. 49%). CONCLUSIONS: The incidence of non-SN metastases seemed to be related to the number of positive SNs and the size of SN metastases. However, in the group of patients with a positive SN, it was not possible to identify a subset of patients without non-SN metastases.

Sentinel lymph node biopsy in breast cancer: guidelines and pitfalls of lymphoscintigraphy and gamma probe detection.

BACKGROUND: Sentinel node (SN) biopsy appears to offer an alternative to routine axillary lymph node dissection (ALND) for staging patients with breast cancer. Various techniques have been studied for identifying the SN, using vital blue dye or radioactive colloid, and initial reports are promising. The inherent limitations and pitfalls must be clearly understood before SN biopsy can be implemented in dinical practice. STUDY DESIGN: In a prospective trial, the feasibility of using lymphoscintigraphy and gamma probe detection for performing SN biopsy was studied. In 130 consecutive patients with T1-T2, N0 breast cancer, preoperative lymphoscintigraphy was performed with technetium 99m-colloidal albumin. During ALND, the radioactive axillary SNs were localized by the gamma probe. Histopathologic examination of the harvested SNs was compared with the status of the axillary lymph nodes. RESULTS: Axillary focal accumulations were clearly identified on lymphoscintigraphy in 116 patients (89%). The failure rate was significantly higher in patients who had a previous excision biopsy (36%) than in those with a palpable tumor in situ (4%). Using the gamma probe, radiolabeled axillary SNs were successfully biopsied in 122 patients (94%). Because 18 of these patients did not undergo formal lymphadenectomy, the predictive accuracy of SN biopsy was analyzed in 104 patients. Radioactive nodes revealed metastases in 44 of 104 patients (42%); in 26 of them (59%), these were the only involved axillary nodes. The SN was negative in 60 patients (58%); in one patient the ALND was found to contain metastatic disease (1.7% false negatives). Biopsy of the SN was 98% accurate in predicting the absence of nodal metastases. CONCLUSIONS: There are certain guidelines for performing SN biopsy by lymphoscintigraphy and gamma probe detection. Success depends primarily on an adequate functional capacity of the SN, necessary for sufficient nodal uptake to ensure accurate identification. Lymphoscintigraphy defines the pattern of lymph flow and may prevent failure or false-negative biopsies. Biopsy of the SN is a highly accurate, minimally invasive method of staging patients with breast cancer and can substantially reduce the morbidity and costs of surgical treatment by avoiding unnecessary ALND in the majority of patients.

Vital dye and radiolabelled colloids--complement or alternative?

Several different protocols for retrieval of the sentinel node (SN) have been described: gamma probe (GP) and/or dye guided biopsy, preceded by lymphoscintigraphy or not. Especially in American studies, predominantly executed by surgeons, dye or GP guidance only is used with good results. The disadvantages of applying dye only are: an extensive learning curve, lower retrieval rate of the SN and, especially in the learning phase, a higher rate of false negative biopsies. If only GP guidance is applied, the technique seems more simple to master. A recent multicentre study, however, revealed an unacceptably high false negative rate. It must be considered that most published studies were executed by highly experienced surgeons. In most European studies, scintigraphy is a standard part of the procedure. Lymphoscintigraphy provides the surgeon with a "road map", revealing the number and approximate location of the SNs in the lymphatic basin(s). Scintigraphy proves useful especially if an SN is situated close to the injection site (breast cancer), or if SNs are situated at unexpected locations (head-and-neck or trunk melanoma). A combination of all three available steps results in the highest number of successful procedures with the lowest false negative rate. This may prove to be especially important for general hospitals where the number of biopsy procedures is often smaller compared to specialized centres.

Transport and retention of colloidal tracers in regional lymphoscintigraphy in melanoma: influence on lymphatic mapping and sentinel node biopsy.

Sentinel node (SN) biopsy is a staging technique used to select patients for regional lymphadenectomy in melanoma. We compared the two most widely used radioactive tracers, 99mTc-colloidal albumin (99mTc-CA) and 99mTc-sulphur colloid (99mTc-SC), with respect to scintigraphy, success rate in gamma probe guided biopsy and absolute uptake in the SN. Scintigraphy was performed in six volunteers after simultaneous injection of the respective tracers in each leg. Comparison of uptake of both tracers showed a higher uptake on the 99mTc-CA side. The scintigraphic count ratio of SNs labelled with 99mTc-SC compared with 99mTc-CA was 1 to 9 28. Next, 20 patients with biopsy-proven melanoma were randomized for injection of 99mTc-CA or 99mTc-SC followed by SN biopsy. Within 20 min after the injection, focal uptake was seen in all cases of the 99mTc-CA group but in only seven of the 10 patients in the 99mTc-SC group (P < 0.05). Focal accumulations were seen in all patients of both groups after 2 h. Spill to non-SNs was seen in five of the 99mTc-CA patients and three of the 99mTc-SC patients. In all patients the SNs could be retrieved under the guidance of a gamma probe and blue dye. The uptake in the SN was significantly higher (P < 0.001) after the injection of 99mTc-CA (0.92+/-0.40%) compared with 99mTc-SC (0.34+/-0.34%). When dynamic scintigraphy is performed, 99mTc-CA is preferable. SN uptake of 99mTc-SC is less than that of 99mTc-CA but this does not adversely affect the surgical procedure.

No indication for performing sentinel node biopsy in melanoma patients with a Breslow thickness of less than 0.9 mm.

In thin melanomas, the involvement of regional nodes is very uncommon. Recent sentinel node (SN) studies have confirmed the absence of positive regional lymph nodes in melanomas < 0.76 mm and a 5% positivity in melanomas between 1.0 and 1.99 mm. The chance of regional lymph node involvement - and therefore whether it is relevant to perform the SN procedure - seems to depend on the Breslow thickness of the primary tumour. However, a Breslow thickness cut-off point has not yet been established. We evaluated a melanoma population that had undergone an SN procedure to determine this point, so that the procedure can be restricted to a smaller group of patients in future. In a total of 348 patients with proven American Joint Committee on Cancer (AJCC) stages I or II cutaneous melanoma with a Breslow thickness > or = 0.5 mm the triple technique was used, consisting of preoperative visualization of the lymph channels from the initial site of the melanoma towards the SN by (dynamic) lymphoscintigraphy, intraoperative visualization of those particular lymph channels and nodes with blue dye, and a gamma probe to measure accumulated radioactivity in radiolabelled lymph nodes. In melanomas thinner than 0.90 mm, no positive SN was found (95% confidence interval 0-5%). This group consisted of 75 patients (22%), with a median follow-up of 31 months. Our data suggest that this procedure need no longer be indicated for almost a quarter of the patient population, because the cut-off point for nodal involvement appears to be a Breslow thickness of 0.90 mm.

Lymphoscintigraphic details of sentinel lymph node detection in 82 patients with squamous cell carcinoma of the oral cavity and oropharynx.

Lymphoscintigraphy for sentinel node (SN) detection has been studied extensively in melanoma and breast cancer. In head and neck squamous cell carcinoma (HNSCC), however, experience in this field is relatively meagre. The purpose of this study was to document and evaluate lymphoscintigraphic findings in HNSCC patients. Eighty-two patients with clinical T1-T4 N0 SCC of the oral cavity or oropharynx received peritumoral injections of 25-75 MBq 99mTc-colloidal albumin (CA). Dynamic lymphoscintigraphy was performed in lateral projection for 20 min, followed by 2 min static imaging in anterior projection. In 26 patients, additional static images were obtained 2-6 h after injection of the tracer. In four of 82 patients, both early and late imaging revealed no tracer transport. In 78 of 82 patients, one (60), two (14) or three (4) SNs could be visualized, either by dynamic scintigraphy (73) or delayed static imaging (5). In 48 of 78 (62%) patients, the SN was visualized within the first minute of dynamic imaging. In particular, SNs of tumours of the mobile tongue were visualized within the first minute. No effect of T-stage or 99mTc-CA dose on the transport time of the tracer towards the SN was seen. The distribution of the SNs in the various levels of the neck relative to the primary tumour sites within the oral cavity was in concordance with the patterns of lymph node metastases reported traditionally for patients with SCC in the oral cavity. This study demonstrates the different variables affecting SN identification with lymphoscintigraphy using 99mTc-CA in HNSCC patients.

Reduced perfusion and uptake of Tc-99m HDP in the iliac bone. A rare presentation of pelvic osteomyelitis.

The authors present a case report of a young patient with two osteomyelitic foci. Bone scintigraphy showed a rare combination of a cold and a hot spot. Possible problems in the interpretation of the scintigram in patients with pelvic osteomyelitis are discussed.

[The sentinel node procedure: standard intervention for surgical treatment of breast cancer]. / De schildwachtklierprocedure: standaardingreep bij de chirurgische behandeling van het mammacarcinoom.

Axillary lymph node dissection may be avoided in the surgical treatment of breast cancer if the sentinel node appears to be free of metastatic tumour cells. The sentinel node concept has been validated in hundreds of patients, in whom this node has been localized successfully by dye-guided node mapping and (or) gamma-probe localization after injection of a radiopharmaceutical agent. The success rate of sentinel node localization depends on different factors, such as type, volume and injection site of the radiopharmacon, choice of the handheld gamma-probe, timing of the blue dye injection, and clinical stage of the disease. The combination of preoperative lymphoscintigraphy, intraoperative gamma-probe guidance and blue dye administration will increase the success rate of a sentinel node biopsy. Recent reports, from both Europe and the United States, appear to indicate that the sentinel node biopsy will soon be standard procedure in the surgical treatment of (T1-2) breast cancer. In the majority of breast cancer patients axillary lymph node dissection, a cause of much morbidity, may thus be avoided.