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.

[Less axillary dissection necessary due to sentinel node biopsy in patients with breast carcinoma]. / Minder okselklierdissectie nodig door schildwachtklierbiopsie bij patiënten met mammacarcinoom.

OBJECTIVE: To determine whether the sentinel node concept is appropriate in patients with breast cancer, notably whether the sentinel node can be identified after peritumoral injection of colloidal 99mTc albumin using lymphoscintigraphy or a handheld gamma probe in the axillary drainage area. DESIGN: Descriptive. SETTING: Academic Hospital Free University, Amsterdam, the Netherlands. METHOD: In 30 consecutive patients with T1 and T2 breast cancer lymphoscintigraphy was performed 2 and 18 hours after peritumoral injection of 40 MBq of colloidal 99mTc albumin injection. Focal accumulations in the axilla were registered and localized in vivo using a handheld gamma probe. All patients underwent axillary lymph node dissection. From each surgical specimen the sentinel node was isolated and examined histopathologically. RESULTS: In 28 of the 30 patients lymphoscintigraphy revealed at least one distinct focal accumulation in the axillary region after 2 and 18 h. In nine women more than one sentinel node was registered: two in six and three in three women. In all 28 patients the node was identified in the surgical specimen by gamma probe. In 19 of the 28 (67%) both the sentinel node and the axillary lymph nodes were without metastasis. Three patients had metastases both in the sentinel and in the other axillary nodes, and in 6 patients (21%) the sentinel node was the only node with metastasis. CONCLUSION: In the majority of breast cancer patients a sentinel node was identified after peritumoral injection of colloidal 99mTc albumin, and with a handheld gamma probe the node could be found in the surgical specimen. In none of the women metastasis was found in other lymph nodes if the sentinel node was unaffected.

The impact of dynamic lymphoscintigraphy and gamma probe guidance on sentinel node biopsy in melanoma.

In cutaneous melanoma, biopsy of the first tumour-draining lymph node (sentinel node, SN) may replace routine elective lymph node dissection (ELND). Even in experienced hands the original technique using vital dyes fails to localise the SN in 20% of cases. In this study we investigated whether the procedure benefits from lymphoscintigraphy and the use of a gamma probe. In 41 patients technetium-99m-colloidal albumin was injected intracutaneously around the scar of the excised tumour. This was followed by dynamic and late static imaging. The first focal accumulation was assumed to be the SN. In all patients at least one SN was found, in 95% within the first 20 min. By showing multiple or ramifying lymphatic channels, dynamic lymphoscintigraphy differentiated between spill and multiple SNs. In all cases the initial focus retained the highest fraction of radioactivity for at least 18 h. The gamma probe was especially useful in the axilla and neck, where it accurately showed the optimal incision site and facilitated the search for deep-seated nodes. Gamma probe-localised SNs were dye-positive in 93% of cases. The SN contained metastases in 20% of the patients. Only in these patients was ELND performed, which revealed that the SN had been the only metastatic node in four of eight cases. We conclude that dynamic lymphoscintigraphy is essential for SN localisation, that tracer kinetics allow flexible timing of surgery, and that the surgical procedure benefits from use of the gamma probe.