Hand-held Gamma-detecting Probe Research Articles

Survival Advantage Following TAG-72 Antigen-Directed Cancer Surgery in Patients With Colorectal Carcinoma: Proposed Mechanisms of Action.

Patients with colorectal carcinoma (CRC) continue to have variable clinical outcomes despite undergoing the same surgical procedure with curative intent and having the same pathologic and clinical stage. This problem suggests the need for better techniques to assess the extent of disease during surgery. We began to address this problem 35 years ago by injecting patients with either primary or recurrent CRC with 125I-labeled murine monoclonal antibodies against the tumor-associated glycoprotein-72 (TAG-72) and using a handheld gamma-detecting probe (HGDP) for intraoperative detection and removal of radioactive, i.e., TAG-72-positive, tissue. Data from these studies demonstrated a significant difference in overall survival data (p < 0.005 or better) when no TAG-72-positive tissue remained compared to when TAG-72-positive tissue remained at the completion of surgery. Recent publications indicate that aberrant glycosylation of mucins and their critical role in suppressing tumor-associated immune response help to explain the cellular mechanisms underlying our results. We propose that monoclonal antibodies to TAG-72 recognize and bind to antigenic epitopes on mucins that suppress the tumor-associated immune response in both the tumor and tumor-draining lymph nodes. Complete surgical removal of all TAG-72-positive tissue serves to reverse the escape phase of immunoediting, allowing a resetting of this response that leads to improved overall survival of the patients with either primary or recurrent CRC. Thus, the status of TAG-72 positivity after resection has a significant impact on patient survival.

A modified sentinel node and occult lesion localization (SNOLL) technique in non-palpable breast cancer: a pilot study

BackgroundThe spread of mammographic screening programs has allowed an increasing amount of early breast cancer diagnosis. A modern approach to non-palpable breast lesions requires an accurate intraoperative localization, in order to achieve a complete surgical resection. In addiction, the assessment of lymph node status is mandatory as it represents a major prognostic factor in these patients. The aim of this study is to evaluate the reliability of a modified technical approach using a single nanocolloidal radiotracer to localize both sentinel node and breast occult lesion.MethodsTwenty-five patients with a single non-palpable breast lesions and clinically negative axilla were enrolled. In the same day of surgery, patients underwent intratumoral and peritumoral administration of 99mTc-labeled nanocolloid tracer under sonographic guidance. A lymphoscintigraphy was performed to localize the sentinel lymph node and its cutaneous projection was marked on the skin in order to guide the surgeon to an optimal incision. During surgery an hand-held gamma-detection probe was used to select the best surgical access route and to guide localization of both occult breast lesion and sentinel lymph node. After specimen excision, the surgical field was checked with the gamma-probe to verify the absence of residual sources of significant radioactivity, thereby ensuring a radical treatment in a single surgical session and minimizing normal tissue excision.ResultsBoth targeted breast lesion and sentinel lymph node were localized and removed at the first attempt in every patients and histopathological diagnosis of malignancy was confirmed in 25/26 samples. Non-palpable lesions were included within the surgical margins in all patients and in all samples surgical margins were free from neoplastic infiltration thus avoiding any further reintervention. Only two patients showed metastatic involvement of sentinel lymph node.ConclusionsThe modified sentinel node and occult lesion localization (SNOLL) technique performed with a single injection of nanocolloidal radiotracer has shown an excellent intraoperative identification rate of both non-palpable lesion and sentinel lymph node. This procedure offers, as opposed to standard techniques, an accurate, simple and reliable approach to the management of non-palpable breast cancer.

Intraoperative Use of a Portable Large Field of View Gamma Camera and Handheld Gamma Detection Probe for Radioguided Localization and Prediction of Complete Surgical Resection of Gastrinoma: Proof of Concept

Surgical management of Zollinger-Ellison syndrome (ZES) relies on localization and resection of all tumor foci. We describe the benefit of combined intraoperative use of a portable large field of view gamma camera (LFOVGC) and a handheld gamma detection probe (HGDP) for indium-111 ((111)In)-pentetreotide radioguided localization and confirmation of gastrinoma resection in ZES. Five patients (6 cases) with (111)In-pentetreotide-avid ZES were evaluated. Patients were injected with (111)In-pentetreotide for diagnostic imaging the day before surgery. Intraoperatively, an HGDP and LFOVGC were used to localize (111)In-pentetreotide-avid lesions, guide resection, assess specimens for (111)In-pentetreotide activity, and to verify lack of abnormal post-resection surgical field activity. Large field of view gamma camera imaging and HGDP-assisted detection were helpful for localization and guided resection of tumor and removal of (111)In-pentetreotide-avid tumor foci in all cases. In 3 of 5 patients (3 of 6 cases), these techniques led to detection and resection of additional tumor foci beyond those detected by standard surgical techniques. The (111)In-pentetreotide-positive or-negative specimens correlated with neuroendocrine tumors or benign pathology, respectively. In one patient with mild residual focal activity on post-resection portable LFOVGC imaging, thought to be artifact, had recurrence of disease in the same area 5 months after surgery. Real-time LFOVGC imaging and HGDP use for surgical management of gastrinoma improve success of localizing and resecting all neuroendocrine tumor-positive tumor foci, providing instantaneous navigational feedback. This approach holds potential for improving long-term patient outcomes in patients with ZES.

Usefulness of sentinel lymph node biopsy for the detection of metastasis in the early stage of extramammary Paget's disease.

Invasive cases of extramammary Paget's disease have a poor prognosis, owing to its rapid progression and resistance to irradiation and chemotherapy. Morton et al. introduced a technique to identify sentinel lymph nodes by local injection of vital dyes and reported its benefit for managing the progress of malignant melanoma. Since the rate of lymph node metastasis of extramammary Paget's disease is not uncommon (reported from 8.5% to 26%), this study tested the hypothesis that sentinel lymph node biopsy would be useful to detect lymph node metastasis in the clinically early stage of extramammary Paget's disease. Eighteen patients with primary extramammary Paget's disease were enrolled in the study. The precise location of sentinel lymph nodes was visualized using either intraoperative patent blue dye injection or indocyanine green dye injection in combination with a hand-held gamma-detecting probe after a 99mTc phytate injection. Of the 18 patients, sentinel lymph node metastasis was identified in 2 (Cases 2 and 15) of the 2 patients with deep invasion and in 1 (Case 12) of the 7 patients with minimal dermal invasion, however, it was absent in 9 patients who had been categorized into the intraepidermal group. This study demonstrates that extramammary Paget's disease possibly causes metastasis via regional lymphatic systems to which the lesion belongs, even in the early stages of no nodule or tumor formation, and that sentinel lymph node biopsy is useful to detect lymph node metastasis.

A Phase 2 Study of 99mTc-Tilmanocept in the Detection of Sentinel Lymph Nodes in Melanoma and Breast Cancer

Several (99m)Tc-labeled agents that are not approved by the U.S. Food and Drug Administration are used for lymphatic mapping. A new low-molecular-weight mannose receptor-based, reticuloendothelial cell-directed, (99m)Tc-labeled lymphatic imaging agent, (99m)Tc-tilmanocept, was used for lymphatic mapping of sentinel lymph nodes (SLNs) from patients with primary breast cancer or melanoma malignancies. This novel molecular species provides the basis for potentially enhanced SLN mapping reliability. In a prospectively planned, open-label phase 2 clinical study, (99m)Tc-tilmanocept was injected into breast cancer and cutaneous melanoma patients before intraoperative lymphatic mapping. Injection technique, preoperative lymphoscintigraphy (LS), and intraoperative lymphatic mapping with a handheld gamma detection probe were performed by investigators per standard practice. Seventy-eight patients underwent (99m)Tc-tilmanocept injection and were evaluated (47 melanoma, 31 breast cancer). For those whom LS was performed (55 patients, 70.5%), a (99m)Tc-tilmanocept hot spot was identified in 94.5% of LS patients before surgery. Intraoperatively, (99m)Tc-tilmanocept identified at least one regional SLN in 75 (96.2%) of 78 patients: 46 (97.9%) of 47 in melanoma and 29 (93.5%) of 31 in breast cancer cases. Tissue specificity of (99m)Tc-tilmanocept for lymph nodes was 100%, displaying 95.1% mapping sensitivity by localizing in 173 of 182 nodes removed during surgery. The overall proportion of (99m)Tc-tilmanocept-identified nodes that contained metastatic disease was 13.7%. Five procedure-related serious adverse events occurred, none related to (99m)Tc-tilmanocept. Our results demonstrate the safety and efficacy of (99m)Tc-tilmanocept for use in intraoperative lymphatic mapping. The high intraoperative localization and lymph node specificity of (99m)Tc-tilmanocept and the identification of metastatic disease within the nodes suggest SLNs are effectively identified by this novel mannose receptor-targeted molecule.

A comparative study of sentinel lymph node detection in laryngeal and hypopharyngeal carcinoma by lymphoscintigraphy method and blue dye

To investigate the clinical value of sentinel lymph node (SLN) detection in laryngeal and hypopharyngeal carcinoma patients with clinically negative neck (cN0) by lymphoscintigraphy method and blue dye. Forty patients with cN0 laryngeal neoplasms and ten patients with cN0 hypopharyngeal carcinoma scheduled for tumor resection and neck dissection, were eligible for the study. single photon emission computed tomography (SPECT)/CT lymphoscintigraphy was performed with injection of radioactivity isotope ⁹⁹Tc(m) labeled sulfur colloid (⁹⁹Tc(m)-SC). Methylthioninium was injected into the same points as ⁹⁹Tc(m)-SC during surgery, and the patients underwent lymphatic mapping with a handheld gamma-detecting probe. All removed lymph nodes were examined by routine histopathology. Thirty-five patients with laryngeal carcinoma and six patients with hypopharyngeal carcinoma detected SLN by radiolabeled tracer method, the detection rate of SLN was 82.0%. Twenty-nine patients with laryngeal carcinoma and 4 patients with hypopharyngeal carcinoma detected SLN by blue dye method, the detection rate of SLN was 66.0%. There were significant difference between two groups (chi² = 2.769, P < 0.05), and the number of SLN were respectively 96 and 83 by radiolabeled tracer method and blue dye (chi² = -2.098, P < 0.05), The sensitivity of SLN detection were respectively 83.3% and 66.7%. Twelve (24.0%) patients had lymph node metastasis. Either lymphoscintigraphy or blue dye mapping can be used to detect the SLN in cN0 laryngeal and hypopharyngeal carcinoma. The lymphoscintigraphy not only preoperatively can locate the accuracy of SLN detection, but also has higher detection rate and sensitivity than dye method.

Operative probe scintimetry with indium and technetium for colorectal cancer

Surgeons introduced the hand-held gamma detection probe in combination with tumor-directed monoclonal antibodies in patients with colorectal cancer. The clinicians conducted innovative research involving antibody chemistry and variation as well as radioactive dosimetry and decay. The results of these studies represented an era when surgeons began reporting on specific lesion detection and the impact of the antibody administration on the management of the patient. The summary of the important early trials involving monoclonal antibodies and probe scintimetry provides a valuable look into the early development of the antibody technology and a glimpse of potential future applications using the gamma detection probe.

Detecção e exérese de lesões mamárias não palpáveis orientadas por cirurgia radioguiada com injeção de ar para controle radiológico

OBJETIVO: avaliar a eficiência da localização e exérese por cirurgia radioguiada de lesões ocultas mamárias utilizando radiofármaco injetado diretamente no interior das lesões ou até dois centímetros destas com posterior injeção de ar como controle radiológico. MÉTODOS: vinte e nove pacientes com 32 lesões mamárias ocultas, detectadas por mamografia ou ultra-sonografia, classificadas como Bi-Rads® 3, 4 e 5 foram incluídas neste estudo observacional com resultados expressos em percentagens. O radiofármaco utilizado foi o macroagregado de albumina marcado com tecnécio-99m (99mTc-MAA) injetado por orientação mamográfica ou guiado por ultra-sonografia. A injeção do radiofármaco foi seguida pela imediata administração de ar, através da agulha da estereotaxia, visando o controle radiológico da injeção do radiofármaco. A biopsia excisional foi feita com o auxílio do aparelho portátil gamma-probe (detector de radiação gama) e a remoção completa das lesões foi verificada pela radiografia das peças cirúrgicas ou por exame por congelação intra-operatório. RESULTADOS: câncer de mama foi encontrado em 10% (1/10) das lesões BI-RADS® 3, em 31,5% (6/19) das BI-RADS® 4 e em 66,6% (2/3) das BI-RADS® 5. As 29 pacientes corresponderam a 32 espécimes, cirúrgicos. O radiofármaco foi corretamente posicionado em 96,8% (31/32) dos espécimes permitindo remoção de 96,8% das lesões mamárias não palpáveis estudadas. A completa remoção da lesão foi demonstrada pela radiografia das peças em 23 casos (71,8%), pelo estudo intra-operatório por congelação em 21,8% (7/32) e por ambos os métodos em 6,2% (2/32). CONCLUSÃO: a cirurgia radioguiada é importante instrumento na remoção de lesões mamárias não palpáveis, tratando-se de método simples, rápido e exeqüível que pode ser implementado na rotina clínica dessas pacientes.

Feasibility of the Detection of the Sentinel Lymph Node in Peripheral Non-small Cell Lung Cancer With Radio Isotopic and Blue Dye Techniques

The objective of this study was to evaluate the feasibility of the sentinel lymph node (SLN) biopsy in peripheral clinically stage I or II non-small cell lung cancer (NSCLC) using (99m)Tc colloid and a hand-held gamma detection probe, associated with a blue dye technique. Prospective study. Royal Brompton Hospital, London, UK; and Hopital Nord, Saint Etienne, France. After thoracotomy, a total of 2 mL patent blue dye mixed with 1,600 muCi (99m)Tc-albumin or (99m)Tc-colloid was injected into each quadrant of lung tissue immediately surrounding the tumor. Routine lymphadenectomy was carried out. The first lymph nodes to stain blue or radioactive, if any, were considered SLNs. Twenty-four patients were evaluated. We successfully identified 17 SLNs in 13 patients (detection rate, 54.2%). Mean time from injection to identification of SLNs was 18 min (range, 5 to 30 min). In nine cases, the SLN was blue and radioactive, in six cases only blue, and in two cases only radioactive. The pathologic status of the SLN reflected the pathologic status of other nodes of the routine lymphadenectomy except one case of false-negative SLN (14%). Four SLNs were in N2 stations (23.5%). The sentinel node mapping in NSCLC with blue dye and radioisotopic techniques is feasible, but the detection rate has to be improved. This technique is an accurate method of identifying the first node draining a tumor, although it is not yet sufficiently sensitive to have a role in reducing the extent of nodal dissection.

Pharmacokinetics and Clinical Evaluation of125I-Radiolabeled Humanized CC49 Monoclonal Antibody (HuCC49ΔCH2) in Recurrent and Metastatic Colorectal Cancer Patients

CC49 is an antitumor monoclonal antibody that is promising for use in radioimmunoguided surgery (RIGS). However, the murine antibody has been limited by human antimouse antibody (HAMA) response and slow clearance. This study examined the pharmacokinetics and tissue localization of a humanized domain-deleted CC49 antibody (HuCC49DeltaC(H)2 MAb) in humans. Twenty-one patients with colorectal carcinoma were given 1 mg intravenous (I.V.) bolus of HuCC49DeltaC(H)2 MAb radiolabeled with 2 mCi (125)I after thyroid blockade. The level of circulating HuCC49DeltaC(H)2 MAb was measured daily as precordial counts using a handheld gamma-detecting probe. Each patient underwent an exploratory laparotomy on postinjection days 3-20. Gamma counts were measured at normal organs, aortic bifurcation (AB), and both clinically evident and occult tumors. Precordial and AB gamma counts showed an excellent linear correlation. HuCC49DeltaC(H)2 MAb followed a two-compartment pharmacokinetic model. Normal organs and AB showed similar exposures to HuCC49DeltaC(H)2 MAb, while HuCC49DeltaC(H)2 MAb favorably distributed into tumors from day 3. Intestinal and metastatic liver lesions showed the highest partition coefficients. All patients showed no HAMA response. C(H)2 region deletion of HuCC49DeltaC(H)2 MAb did not alter the pharmacokinetics compared to murine CC49. The favorable partition coefficient K of HuCC49DeltaC(H)2 MAb into tumors supports its use in RIGS.

Sentinel lymph node biopsy in patients with extramammary Paget's disease.

Patients with invasive extramammary Paget's disease appear to have a risk of regional lymph node metastasis. Despite the poor prognosis for patients with lymph node metastasis, management of extramammary Paget's disease without clinical evidence of involved nodes is controversial. To evaluate the usefulness of sentinel lymph node biopsy, patients with extramammary Paget's disease underwent sentinel lymph node biopsy using preoperative lymphoscintigraphy and intraoperative patent blue dye injection with a handheld gamma-detecting probe. Thirteen patients with primary genital extramammary Paget's disease were included in the study. Sentinel nodes identified were excised and examined by hematoxylin and eosin staining. All sentinel lymph nodes were also subjected to immunohistochemical staining for carcinoembryonic antigen, MUC1, cytokeratin 7, and gross cystic disease fluid protein-15. A total of 23 nodes were removed successfully. Tumor cells were detected in 4 nodes from four patients by hematoxylin and eosin staining. No additional lymph nodes were positive by immunohistochemistry. Three of the four sentinel-node-positive patients developed distant metastases. All nine patients without node involvement were free from disease during the follow-up period. Sentinel lymph node biopsy was safe and feasible method and may have an important role in the management of extramammary Paget's disease with clinically N0 status. To establish the optimal management of inguinal lymph nodes in extramammary Paget's disease, additional studies in large number of patients are needed.

1031 99mTc-MIBI myocardial perfusion scintigraphy for assessment of radiation induced cardiac damage — preliminary results

Surgical management of Zollinger-Ellison syndrome (ZES) relies on localization and resection of all tumor foci. We describe the benefit of combined intraoperative use of a portable large field of view gamma camera (LFOVGC) and a handheld gamma detection probe (HGDP) for indium-111 (111In)-pentetreotide radioguided localization and confirmation of gastrinoma resection in ZES.Five patients (6 cases) with 111In-pentetreotide-avid ZES were evaluated. Patients were injected with 111In-pentetreotide for diagnostic imaging the day before surgery. Intraoperatively, an HGDP and LFOVGC were used to localize 111In-pentetreotide-avid lesions, guide resection, assess specimens for 111In-pentetreotide activity, and to verify lack of abnormal post-resection surgical field activity.Large field of view gamma camera imaging and HGDP-assisted detection were helpful for localization and guided resection of tumor and removal of 111In-pentetreotide-avid tumor foci in all cases. In 3 of 5 patients (3 of 6 cases), these techniques led to detection and resection of additional tumor foci beyond those detected by standard surgical techniques. The 111In-pentetreotide–positive or–negative specimens correlated with neuroendocrine tumors or benign pathology, respectively. In one patient with mild residual focal activity on post-resection portable LFOVGC imaging, thought to be artifact, had recurrence of disease in the same area 5 months after surgery.Real-time LFOVGC imaging and HGDP use for surgical management of gastrinoma improve success of localizing and resecting all neuroendocrine tumor–positive tumor foci, providing instantaneous navigational feedback. This approach holds potential for improving long-term patient outcomes in patients with ZES.

Minimal sentinel node procedure for staging early breast cancer.

Sentinel lymph node dissection (SLND) has recently been evaluated as a new staging technique for early breast cancer. To minimize the extent of surgery, the feasibility of eradicating primary breast lesions and the relative sentinel lymph nodes (SLN) under regional anesthesia was evaluated in this study. A selected population of 76 patients with suspected operable breast cancer and no clinically palpable lymph nodes was enrolled in the study. Intra- and perilesional administration of a radiotracer was performed. Lymphoscintigraphy was carried out to confirm the drainage pathway and locate the SLN. The following day, after inducing a nervous block induction of the ipsilateral intercostal nerves, we performed the surgical procedure with the help of a hand-held gamma-detecting probe. In case the primary lesion was diagnosed as invasive carcinoma by frozen section, the SLN and the remaining axillary lymph nodes (non-SLNs) were removed. The status of SLN and non-SLNs was compared. The primary breast lesion was located and excised in all cases (identification rate: 100%). Lymphoscintigraphy positively identified SLNs in 40/45 (89%) patients; in five patients no lymphatic drainage was detected. In 38 cases an average of 1.5 SLNs and 14 non-SLNs per patient were removed and pathologically analyzed; the remaining two patients showed SLNs in the internal mammary chain, which were not excised. Twenty-nine percent of the patients showed metastatic disease in the lymph nodes examined. Of all patients with affected nodes, 55% had cancer cells only in the SLN. No false negatives (skip metastases) were found. No immediate or long-term anesthesia-related complications (e.g., pleural lesions, intravascular injection) were observed. Our data confirm the feasibility of single radiotracer administration for both occult lesion and SLN localization as well as the usefulness of SLND in staging early breast cancer. Regional anesthesia resulted in easy management and good patient compliance. This time-saving procedure allowed the completion of the whole surgical plan, reducing the recovery time without modifying the effectiveness of surgery.

Radiolabeled peptides in diagnosis and tumor imaging: Clinical overview

The authors briefly review radiopeptides currently approved for use in the United States. They present a short review of the peptide somatostatin's actions and also note the five somatostatin receptors (SSTRs) to which the peptide and its synthetic analogs octreotide, lanreotide, and vapreotide bind. The many conditions besides neuroendocrine tumors having SSTRs are listed. Labeled octreotide and the other two analogues have a strong affinity for SSTR2 and SSTR5, which thereby produce positive imaging. The various neuroendocrine tumors best imaged by somatostatin receptor scintigraphy (SRS) are discussed, and the exceptions (insulinoma and medullary thyroid carcinoma) are noted to be seen better with labeled VIP and (99m)Tc-dimethylsuccinic acid (DMSA), respectively. SRS and VIP receptor scintigraphy are also noted to image many nonneuroendocrine tumors, which often have appropriate receptors. Several of the currently emerging and very effective new imaging techniques are described. These include (99m)Tc-DMSA for medullary thyroid carcinoma, (18)F dihydroxyphenylalanine positron emission tomography, and C(11) 5-hydroxytryptophan positron emission tomography scanning for all neuroendocrine tumor, but especially carcinoid tumor, metastases. The special role of SRS in identifying gastric carcinoid tumors in hypergastrinemic patients is reviewed. Various pitfalls in interpreting SRS are presented and receptor-enhancing techniques described. Besides use of SRS (mainly Octreoscan, Mallinckrodt Medical, St. Louis, MO) only for detecting and localizing primary tumors and metastases for staging, there are many additional special uses for clinical management of SRS-positive tumors. These include the intraoperative use of the handheld gamma-detecting probe. A brief enumeration is given of the most promising of other non-SST G-protein-coupled receptors and ligands currently under development. Finally, we have posed a number of questions for which answers are needed in the immediate future to facilitate better imaging. Extrapolations of current knowledge and experience with radiolabeled peptide pharmaceutical imaging are converted to reasonable speculations of anticipated future developments in this field.

Lymphatic Mapping of Sentinel Nodes in Early Vulvar Cancer

Objective. The aim of the study was to determine the diagnostic accuracy and feasibility of sentinel lymph node (SLN) detection using a gamma probe in patients suffering from vulvar cancer.Methods. From May 1998 to November 2000, 26 patients with early vulvar cancer, planned for local wide excision or vulvectomy including groin dissection, were eligible for the study. Two to 3 h before the planned procedure we injected technetium99 m-labeled microcolloid intradermally at four locations around the tumor. Dynamic and static images were recorded using a gamma camera. SLN locations were marked on the overlying skin. In the operating theater SLNs were identified at the beginning of the procedure using a handheld gamma-detection probe. After resection of suspected SLNs a standard unilateral or bilateral groin dissection was performed, subsequently followed by local wide excision or, if indicated, radical vulvectomy. Sentinel node detection using technetium99 m-labeled microcolloid was compared with final histopathological and immunohistochemical results.Results. Scintigraphy showed focal uptake in all 26 patients. Intraoperatively we detected all sentinel nodes by handheld gamma probe. In 20 patients, one sentinel node was identified unilaterally, while in 6 patients two or more nodes were identified bilaterally. Histologically positive SLNs were found in 9 patients. In our preliminary series we did not find any false-negative SLN.Conclusion. Identification of sentinel nodes in vulvar cancer is feasible with preoperatively administered technetium99m-labeled microcolloid. We confirm the results of previous studies and improve the evidence that the SLN procedure could be implemented in future therapy concepts.

Sentinel node procedure in Ib cervical cancer: a preliminary series.

The aim of this study was to determine the diagnostic accuracy and feasibility of sentinel lymph node (SLN) detection using a gamma probe in patients with Figo IB cervical cancer. Between January 1999 and September 2000, 14 patients with cervical cancer, planned for radical hysterectomy were eligible for the study. The day before radical hysterectomy we injected technetium99m-labelled nanocolloid in each quadrant of the cervix. Dynamic and static images were recorded using a gamma camera. SLNs were identified intraoperatively using a handheld gamma-detection probe. After resection of SLNs a standard radical hysterectomy with pelvic lymph node dissection was performed. Patients and tumour characteristics were compared with sentinel node detection and with final histopathological and immunohistochemical results. Scintigraphy showed focal uptake in 13 of the 14 patients. Intraoperatively we detected 26 sentinel nodes by gamma probe. In 8 of 13 patients, one or more sentinel nodes were identified unilaterally, in 5 women bilaterally. Histologically positive SLNs were found in only 1 patient. We did not find any false-negative SLN in our series. In conclusion identification of sentinel nodes in cervical cancer is feasible with preoperatively administered technetium99m-labelled nanocolloid. A larger series will be required to establish sentinel node detection in cervical cancer for further therapy concepts and planning. © 2001 Cancer Research Campaignhttp://www.bjcancer.com

Radioimmunoscintigraphy in Patients with Ovarian Cancer

The use of radiolabeled monoclonal antibodies (MoAbs) has significantly improved the ability to detect tumor antigens, thus improving in vivo tumor diagnosis and treatment. The management of ovarian carcinoma still poses a challenging medical problem. Clinical trials using radioimmunoscintigraphy or a hand-held gamma detection probe intraoperatively were performed in patients with clinical evidence of primary or recurrent ovarian cancer. Immunoscintigraphy of ovarian cancer lesions has been performed mainly with 99mTc, 111In and 123I labeled with HMFG1, HMFG2, OC-125, B72.3, H17E2, OVTL3, MoAb170, Mov18 and other MoAbs. Antibody guided imaging using radioimmunoscintigraphy has demonstrated improved targeting of ovarian cancer, resulting in a highly sensitive and specific method. However, it is not yet known which type of MoAb is the most efficient for radioimmunoscintigraphy. Since these tumors represent a potentially curable disease, radioimmunoscintigraphy could contribute mainly to accurate staging as a supplementary to conventional diagnostic methods, as well as for the localization of active disease after chemotherapy and monitoring for the presence of recurrent disease. Nevertheless, prospective studies in a large number of patients should be undertaken in order to further evaluate the diagnostic contribution of this approach.

Sentinel Node Biopsy Interpretation: The Milan Experience.

From March 1996 to December 1999 we performed 1,266 sentinel node biopsies (SNBs) in patients with small breast cancers. The technique is to inject technetium 99m-labeled albumin particles close to the tumor, locate the sentinel node (SN) scintigraphically, and use a handheld gamma-detecting probe to guide its removal via a small incision during breast surgery. Our experience was divided into three phases. In the first phase, complete axillary dissection was performed to assess the accuracy of SNB in predicting axillary status. We also assessed safety, perfected tracer injection technique, determined optimal particle size and radioactivity levels, optimized lymphoscintigraphic scanning, and perfected the surgical technique. The SN was identified and removed in 98.7% of cases. Comparison with complete axillary dissection showed that the SN predicted axillary status in 96.8% of cases. However, use of an intraoperative frozen section method predicted axillary status in only 86.5% of cases. In the second phase we developed a new method for intraoperative histologic analysis. Extensive sampling (up to 60 sections/SN) and an experienced pathologist proved more important than use of antikeratin immunostaining in identifying tumor cells, and the new method has the accuracy of a definitive histologic examination. The third phase, a randomized trial, closed at the end of 1999. Trial objectives were to confirm that the SN predicts axillary status, to determine the number of axillary relapses, and to assess overall and disease-free survival. Patients were randomized in the operating room to complete axillary dissection or SNB. If the SN was positive, complete axillary dissection was performed; if the SN was negative, no further axillary treatment was given. We expect the trial to confirm our clinical experience that SNB is a safe and accurate procedure for staging patients with early breast cancer and a clinically negative axilla.

Tracing an unhandled suspect lesion through a gamma probe.

This article describes the efforts of the authors in developing a handheld gamma detection probe and addresses a tentative surgical protocol for tracing an unhandled suspect lesion through an albumine-aggregate 99Tcm tracer operative mapping. The electronic and software design for the system is discussed as well as its electronic and nuclear calibration. A phantom model mimicking a breast was built in order to help in the calibration of the system. Earliest results in an external detection procedure using the model and a 0.3 ml tracer sample (7 MBq activity) are presented.

Dye- and gamma probe-guided sentinel lymph node biopsy in breast cancer patients: using patent blue dye and technetium-99m-labeled human serum albumin

Sentinel lymph node (SLN) biopsy is a promising method for the diagnosis of the axillary nodal status. We examined the availability of the SLN biopsy using two mapping procedures: the dye- and gamma probe-guided method, and preoperative lymphoscintigraphy by gamma camera imaging. We enrolled 48 patients with breast cancer. Technetium-99m-labeled human serum albumin was injected into the subdermal tissue above the primary tumor or biopsy cavity, and preoperative gamma camera imaging was performed. After induction of general anesthesia, patent blue dye was injected into the peritumoral area prior to the surgical procedure. A handheld gamma-detection probe was used to assist in SLN detection. Careful dissection was performed to identify blue-stained afferent lymphatic vessels and nodes. An SLN was defined as any blue and/or radioactive node, and was excised. After SLN biopsy, axillary lymph node dissection of level I, II, and III was completed, in order to confirm the diagnostic ability of the SLN biopsy. Intraoperative SLN identification of axillary lesions was successful in 43 of 48 patients (90%). The dye- and gamma probe-guided method was successful in 25 patients (52%), the dye-guided method alone succeeded in 11 patients (23%), and the gamma probe-guided method alone succeeded in 7 patients (15%). Preoperative lymphoscintigraphy revealed axillary focal accumulations in 29 of 48 patients (60%). All patients who underwent successful preoperative SLN identification by lymphoscintigraphy had successful intraoperative SLN identification. A diagnostic accuracy of 95%, a sensitivity of 89%, and a specificity of 100% were achieved in the diagnosis of axillary metastasis. Internal mammary SLNs were identified in four patients intraoperatively, but we could not detect cancer metastasis in the internal mammary SLNs. The dye-guided and gamma probe-guided methods were complementary. Preoperative lymphoscintigraphy was useful to predict intraoperative SLN identification. Further study is necessary to assess the role of SLN biopsy of the internal mammary lymph nodes.