PET probe-guided surgery

Intraoperative localization of PET-positive recurrent/metastatic lesions can be facilitated using a hand-held PET probe. PET probe is a high-energy gamma probe designed to process the 511 keV photons of PET tracers. Intraoperative gamma probe performance is a function of radiopharmaceutical uptake, clearance kinetics, and probe engineering, all determining the target to background ratio (TBR) and detection threshold. A minimum TBR of 1.5:1 is needed in the operative field for the operating surgeon to be comfortable the differences between tumor tissue and normal adjacent tissue are real. Due to high-energy photon fluxes, achieving a satisfactory TBR intraoperatively is challenging and requires development of a clinically feasible PET-probe guided surgery protocol.     

Gamma probe location of 111indium-labeled B72.3: an extension of immunoscintigraphy.

Eight colorectal and 5 ovarian cancer patients were evaluated with preoperative immunoscintigraphy and intraoperative gamma probe detection of 111indium-labeled monoclonal antibody B72.3. Immunoscintigraphy detected the presence of tumor in every patient shown to have tumor at surgery. There was one false-positive scan. A total of 21 pathologically verified lesions were identified at surgery in the 11 patients with tumor. Immunoscintigraphy localized 12 (57%) and intraoperative gamma probe detection located 17 (81%) of the lesions. Intraoperative probe detection located 6 of 8 lesions smaller than 1 cm and 3 lesions that were not identified on initial surgical exploration. The gamma probe offers information that is complementary to immunoscintigraphy in that (1) it aids the surgeon in locating intra- and extra-abdominal lesions previously identified by immunoscintigraphy, (2) it locates lesions too small to be seen by immunoscintigraphy alone, (3) it locates lesions that otherwise might be missed at surgery, and (4) it provides objective evidence for adequacy of surgical resection of cancer in the abdominal cavity.     

Intraoperative gamma probe detection of head and neck paragangliomas with 111In-pentetreotide: a pilot study

AIMS AND BACKGROUND: The aim of this study was to assess whether intraoperative radiolocalization of head and neck paragangliomas with 111In-pentetreotide may increase surgical effectiveness, reducing the risk of recurrence. METHODS: Our study included eight patients with untreated, recently diagnosed paragangliomas (four unilateral and four bilateral tumors of the carotid body). After i.v. injection of approximation 150 MBq 111In-pentetreotide, preoperative somatostatin receptor scintigraphy (SRS) was performed. SPECT of the neck was performed at four hours and planar images of the head and neck were also obtained at four and 24 hours post injection. Scintigraphy was always compared with the results of conventional imaging methods (MRI, angiography and sonography). Intraoperative detection was performed on 11 lesions 24 hours after radiopharmaceutical administration using a handheld gamma probe. RESULTS: Preoperative SRS showed high radiotracer uptake in all patients. All the intraoperatively detected lesions were radically resected and histologically confirmed to be involved by tumor. No false positive results were recorded. Gamma probe detection revealed a small intracranial extension not detected by other imaging methods in a patient with a paraganglioma of the right carotid, and partial involvement of the carotid artery in another patient. During follow-up (median 3.5 years; range, 4 months-7 years) all patients remained disease free according to all parameters. CONCLUSIONS: To our knowledge, this is the first experience of radioguided surgery in paraganglioma. Although our study included a relatively small number of patients, we suggest that intraoperative gamma probe detection may be a powerful tool to improve surgical effectiveness.     

Detection of sentinel nodes by lymphoscintigraphy and gamma probe guided surgery in vulvar neoplasia

BACKGROUND: Pathologic lymph node status is the most important prognostic factor in vulvar cancer; however, complete inguinofemoral node dissection is associated with significant morbidity. Intraoperative lymphoscintigraphy associated with gamma detecting probe-guided surgery has proved to be reliable in the detection of sentinel node (SN) involvement in melanoma and breast cancer patients. The present study evaluates the feasibility of the surgical identification of inguinal sentinel nodes using lymphoscintigraphy and a gamma detecting probe in patients with early vulvar cancer. METHODS: Technetium-99-labeled colloid human albumin was administered perilesionally in 44 patients. Twenty patients had T1 and 23 had T2 invasive epidermoid vulvar cancer; one patient had a lower-third vaginal cancer. An intraoperative gamma detecting probe was used to identify SNs during surgery. Complete inguinofemoral node dissection was subsequently performed. SNs underwent separate pathologic evaluation. RESULTS: A total of 77 groins were dissected in 44 patients. SNs were identified in all the studied groins. Thirteen cases had positive nodes: the SN was positive in all of them; in 10 cases the SN was the only positive node. Thirty-one patients showed negative SNs: all of them were negative for lymph node metastasis. CONCLUSIONS: Lymphoscintigraphy and SN biopsy under gamma detecting probe guidance proved to be an easy and reliable method for detection of SNs in early vulvar cancer. If these preliminary data will be confirmed, the technique would represent a real progress towards less aggressive treatment in patients with vulvar cancer.     

Radioimmunoguided breast surgery using radiolabeled antibody NR-LU-10 FAB: a pilot study

AIM AND BACKGROUND: Radioimmunoguided surgery using radiolabeled NR-LU-10 Fab was evaluated as a method of intraoperative breast cancer detection. METHODS: Breast cancer patients were injected intravenously with 125I (74 MBq) labeled NR-LU-10 Fab (5 mg) and then underwent tumor excision 2, 4 or 7 days later, during which time the gamma detector probe was used to evaluate the primary tumor for evidence of radioactive uptake. RESULTS: Intraoperative probing revealed tumor localization in 7 of 10 patients (70%). Gamma probe counts of the excised tumor were elevated in all patients, although high counts in surrounding non-malignant tissue obscured the ability to detect the tumor in vivo in 3 patients. One patient with bilateral breast cancer was found to have a separate focus of occult tumor in each breast using the gamma detector probe. CONCLUSIONS: Radiolabeled NR-LU-10 Fab possesses favorable pharmokinetics and tumor-binding ability as a targeting agent. However, binding to non-malignant tissue limits its role in the intraoperative evaluation of tumor margins in breast cancer patients. Its role in other malignancies should be explored.     

Intraoperative gamma probe detection of lymph node recurrence of insulinoma

Insulinomas are rare endocrine tumors that are mostly sporadic, benign, and small. Preoperative radiography diagnosis may be difficult. Intraoperative palpation and ultrasound remain the gold standard for detection and planned resection. Recent studies find intraoperative gamma-probe localization as a good technique for identifying primary neuroendocrine tumors. We report a case of a 75-year-old woman with functioning lymph node recurrence of a malignant insulinoma. Spleno-pancreatectomy was performed in order to treat the malignant insulinoma. Clinical, biochemical, and radiological examination confirmed the total excision of the primary lesion. However, clinical symptoms appeared 9 months later. Octreo-scan, abdominal CT, and biochemical study showed lymph node recurrence and four hepatic metastases. Surgery was performed after two [111In-DTPA] octreotide scans. Intraoperative gamma probe detection was planned in order to localize a small latero-aortic lymph node recurrence. Intraoperative count rates were high in para-aortic tissue. Para-aortic lymphadenectomy and metastasectomy were carried out. Ex-situ count rates and histological examination confirmed the recurrence. Six months later clinical and biochemical studies and scans remain negative for recurrence. Intraoperative [111In-DTPA] octreotide gamma probe examination may be a useful tool in the surgical approach to insulinoma recurrence.     

Intraoperative radiochromoguided mapping of sentinel lymph node in colon cancer

AIMS AND BACKGROUND: The aim of our study was to assess the feasibility of sentinel lymph node (SLN) detection in colon cancer using a radiochromoguided technique. The regional lymph node status is crucial for colorectal cancer staging and the stage of disease at the time of diagnosis is the main factor influencing therapeutic decision-making and patient survival. METHODS AND STUDY DESIGN: Between April and June 2001 eight patients with colon cancer were studied by radiochromoguided sentinel lymph node mapping. At the time of surgery 2 ml of patent blue dye was injected around the tumor, followed after 10 minutes by 2 ml of 99mTc-labeled albumin. After 30 minutes the SLN was identified by a gamma probe. Surgery was completed by standard resection. The SLN was processed for permanent hematoxylin and eosin staining and for immunohistochemical examination with anti-CEA and anti-cytokeratin antibodies. RESULTS: SLNs were identified in six patients; two were negative for metastasis by hematoxylin-eosin and immunohistochemical examination, two were positive for metastasis by both methods, and two were negative for metastasis by hematoxylin-eosin but positive by immunohistochemical examination. There were no false negative SLNs and no complications occurred. CONCLUSION: The actual utility of SLN detection for prognostic purposes is still unknown, but intraoperative radiochromoguided SLN mapping is technically feasible in colon cancer, although it is associated with more technical difficulties than in breast cancer and malignant melanoma.     

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

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.     

Gamma probe-guided thoracoscopic surgery of small pulmonary nodules

Video-assisted thoracic surgery (VATS) is an interesting and emerging procedure for the diagnosis and treatment of peripheral pulmonary nodules. We developed a new radioguided surgical technique for the detection during VATS of pulmonary nodules smaller than 2 cm, situated deep in the lung parenchyma and neither visible nor palpable with endoscopic instruments. The procedure is divided into two phases. Two hours before surgery 0.3 ml of a solution composed of 0.2 mL of 99mTc-labeled human serum albumin microspheres (5-10 MBq) and 0.1 mL of non-ionic contrast is injected into the lesion under CT guidance. Then the patient is submitted to VATS. During thoracoscopy a collimated probe of 11 mm diameter connected to a gamma ray detector is introduced via an 11.5 mm trocar and the pleural surface of the suspected area is scanned. A hot spot indicates the presence of the radiolabeled nodule and hence the area to be resected. We treated 39 patients with small pulmonary nodules (mean size, 8.3 mm; range, 4-19 mm). The patients were 27 men and 12 women (mean age, 60.8 years; range, 13-80 years). Nineteen patients had a history of synchronous or metachronous malignancy. In all cases the nodule was detected and resected and the resection margins were pathologically free of tumor. Histological examination showed 21 benign and 18 malignant lesions (7 metastases and 11 primary lung cancers). Nine patients with a frozen section-based histopathological diagnosis of lung cancer without functional contraindications underwent a completion lobectomy by open surgery in the same surgical session. In conclusion, the radiolocalization of small pulmonary nodules by gamma probe during VATS is a safe and easy procedure, with fewer complications and a lower failure rate than other localization techniques.     

Rapid and accurate method for delineating cancer lesions in laparoscopic colectomy using activated carbon injection

The aim of our study was to evaluate the clinical efficacy of preoperative injection of activated carbon in delineation of cancer location in laparoscopic colectomy. Activated carbon particles were injected during endoscopy into the normal colonic wall surrounding cancer lesions in five cases of early colon cancer, prior to laparoscopic surgery. The carbon-stained area was clearly recognizable as a blackened patch on the serosal surface of the colon. Using the carbon-stained area as a reference point, partial colectomies were successfully performed on all five patients. The preoperative injection of activated carbon assisted in the intraoperative delineation of early colonic cancer lesions. This method is recommended for the rapid and accurate delineation of early colonic cancers in laparoscopic surgery. © 1995 Wiley-Liss, Inc.     

Preliminary study of sentinel node identification with 99mTc colloid and blue dye in patients with endometrial cancer

AIMS AND BACKGROUND: Intraoperative lymphatic mapping and sentinel node (SLN) biopsy have generated a tremendous amount of interest and are already established as part of the standard practice in the surgical management of breast cancer and melanoma. To reduce extensive radical procedures and decrease the morbidity in the treatment of gynecologic malignancies, much effort is being made to use less aggressive interventions. The purpose of our study was to determine the feasibility of SLN mapping in a group of patients with endometrial cancer at early stages. METHOD AND STUDY DESIGN: Between September 2000 and May 2001 11 patients with endometrial cancer FIGO stage Ib (n = 10) and IIa (n = 1) underwent laparoscopic SNL detection during laparoscopy-assisted vaginal hysterectomy with bilateral salpingo-oophorectomy and bilateral systematic pelvic lymphadenectomy. Radioactive isotope injection was performed 24 hours before surgery and blue dye injection was performed just before surgery in the cervix at 3,6, 9 and 12 hours. A 350 mm laparoscopic gamma scintyprobe MR 100 type 11, 99mTc settled (Pol Hi Tech), was used intraoperatively for SLN detection. RESULTS: Seventeen (17) SLNs were detected with lymphoscintigraphy (six bilateral and five unilateral). At laparoscopic surgery we found the same locations belonging at internal iliac lymph nodes (the so-called Lebeuf-Godard area, lateral to the inferior vesical artery, ventral to the origin of the uterine artery and medial or caudal to the external iliac vein). Fourteen (14) SLNs were negative on histological analysis and three were positive for micrometastases (mean SLN sections = 60). All other pelvic lymph nodes were negative at histological analysis. The same SLN locations detected with the gamma scintyprobe were observed at laparoscopy after patent blue dye injection. CONCLUSIONS: Our preliminary data suggest that combined 99mTc-labeled colloid and vital blue-dye techniques are feasible for SLA detection in endometrial cancer; they represent a very promising tool to transform the management of early-stage endometrial cancer. The clinical validity of this combined technique should be evaluated prospectively.     

Sentinel node biopsy for malignant melanoma: analysis of a four-year experience

AIMS AND BACKGROUND: Sentinel node (SN) biopsy has been introduced to solve the controversy concerning the effectiveness of prophylactic lymphadenectomy in intermediate thickness melanoma. The aim of this study was to evaluate the rate of metastases, the technical details of the procedure, and the main reasons of failure. METHODS: 235 patients affected by intermediate thickness melanoma (tumor thickness >0.75 mm and <4 mm) without clinical signs of systemic spread (N0M0) were submitted to sentinel node biopsy between 1996 and 2000. Preoperative lymphoscintigraphy was routinely performed in the last 184 patients. Intraoperative mapping with gamma probe was combined with the use of vital dye for identification of sentinel nodes in the last 113 patients. RESULTS: The SN detection rate was 95.6%, with significant differences depending on the site of dissection and the use of a gamma probe. The overall rate of micrometastases was 14.7%, but relevant differences were recorded between different subgroups of patients (T2, 5.1%; T3a, 19.6%; T3b, 29%). CONCLUSIONS: Sentinel node biopsy requires a multidisciplinary approach (surgery, pathology and nuclear medicine) for reliable results. The association of vital dye and intraoperative gamma probe for sentinel node harvesting has made the procedure more effective, less time-consuming and less invasive. Failures may be due not only to surgical mistakes, but also to improper nuclear medicine procedures or inaccurate histological evaluation of SNs. Methods for histological examination of the SN are still debated and not standardized but promising results have recently been obtained with molecular oncology techniques (RT-PCR).     

Performances of a new prototype handheld scintillating probe for the search of sentinel lymph nodes in breast cancer.

AIM: The aim of this study is to evaluate the performances of a new prototype handheld gamma probe in a series of patients with infiltrative breast cancer justifying sentinel lymph node (SLN) excision. METHODS AND PATIENTS: SLN excision was performed on nine patients being treated for infiltrative breast cancer. After preoperative radio-isotope injection and lymphoscintigraphy, individual removal of all radioactive nodes was performed after their localisation using a novel new prototype handheld gamma intraoperative probe named CarolIReS. The activity of SLN following resection has been measured by a gamma ray counter. The mean geometrical detection efficiency of this gamma ray counter has been obtained by Monte Carlo simulation. RESULTS: With respect to the total number of SLNs identified by the CarolIReS probe, the detection probability was 80% for the lymphoscintigraphy. A mean number of 2.2 (1-5) SLNs per patient was detected after the complete SLN procedure. Among the removed SLNs, 19 were axillary SLN, 17 were located in the level I of Berg, two were located in the Rotter area and one was an intramammary SLN (ISLN) located in the lower inner area of the breast. The detection efficiency of the CarolIReS probe ranged from 2.1 to 100.0cpskBq(-1) referred to the activity of the SLN at the time of the surgery. CONCLUSION: This study shows that the CarolIReS probe is well adapted to the SLN detection and allows an efficient identification of both axillary and intramammary lymph nodes.     

Radioguided occult lesion localization (ROLL) and excision of breast lesions using technetium-99m-macroaggregate albumin and air injection control

The aim of this study was to assess the efficiency of the radioguided localization and excision technique using radiopharmaceuticals injected directly or close to occult breast lesions. We studied thirty-two consecutive patients with thirty-six occult breast lesions detected mammographically or ultrasonically categorized as BI-RADS 3, 4 or 5. Macroaggregate Albumin (MAA) labeled with (99m)Tc was administered directly or close to the lesion, guided by mammography or ultrasound, followed by an air injection for radiological control. The excision biopsy was carried out with the aid of a hand-held gamma detecting probe and the entire removal of the lesion was verified by X-ray of the surgical specimens or by intraoperatory frozen section examination. Breast cancer was found in 8.3% of BI-RADS 3 lesions, in 33.3% of the BI-RADS 4 lesions and in 66.6% of the BI-RADS 5 lesions. The radiotracer was correctly positioned in 97.2% of the specimens (35/36) allowing the removal of 97.2%. Xray confirmed the entire removal in 27 lesions (75%), intraoperatory frozen section study in 19.4% (7/36) and by both methods in 5.5% (2/36). Radioguided surgery turned out to be an important tool in the removal of non-palpable breast lesions, as a simple, fast and feasible method that can be implemented in the clinical routine of patients with non-palpable breast lesions.     

Lymphoscintigraphic localization of sentinel node in early colorectal cancer: results of a monocentric study

BACKGROUND AND OBJECTIVES: Evaluation of the feasibility of the sentinel node technique in early colorectal neoplasms and its overall accuracy in predicting nodal metastases. METHODS: Thirty-five patients with colon or rectal lesions or degenerate polyps not radically excised by endoscopy were included. Lymphatic mapping was performed with 99mTc labeled albumin colloid injected submucosally by an endoscopic route the afternoon before the surgical procedure. The day of the intervention, 2.5% patent blue V dye (S.A.L.F: Italy) was injected circumferentially around the tumor. A hand held gamma detecting probe (Scintiprobe m100, Pol-Hi-Tech, Italy) was employed to detect "hot" nodes, in vivo and ex vivo. All sentinel nodes were embedded separately for haematoxylin and eosin staining. No IHC or PCR techniques were employed. RESULTS: Sentinel lymph nodes (SLN) were successfully identified in 35 out of 35 patients. Concordance between SLN and nodal status was observed in 32 out of 35 cases (91.4%); four patients (11.4%) were upstaged. Three skip nodal metastases were observed (false-negative rate: 8.5%). CONCLUSIONS: The sentinel node technique with blue dye and radiotracer seems valuable in early colorectal cancers detected by screening programs: a good organization and a learning curve are needed, as further multicentric studies.     

99mTc-硫胶体术前淋巴显像在乳腺癌前哨淋巴结活检中的应用*

目的:探讨用99mTc- 硫胶体（99mTc-Sulfur colloid ,SC）术前淋巴显像在乳腺癌前哨淋巴结活检（sentinel lymph node biopsy ,SLNB）中的临床应用。方法:选择2009年7 月到2010年1 月本院收治的70例乳腺癌患者,于乳腺肿块周围3 点、6 点和12点位置各注射99mTc-Sc37MBq 后15min、30min、1h、2h 行前哨淋巴结（sentinel lymph node ,SLN ）显像,术中用γ 探针探测“热点”淋巴结分析术前淋巴显像与术中探测检测乳腺癌SLNB的结果。结果:术前99mTc-Sc 淋巴显像成功确定60例患者（85.71%）的前哨淋巴结,5 例患者（7.15%）发现腋窝以外的前哨淋巴结。淋巴显像确定SLN 的成功率与原发肿瘤病理类型、临床分期、肿瘤部位等因素无显著性相关（均P>0.05）;与注射同位素到显像的时间有显著相关性（均P<0.05）。 术中确定SLN 的成功率在术前淋巴显像成功组与失败组之间有统计学差异（P<0.05）。 结论:乳腺癌SLN 术前淋巴显像在乳腺癌前哨淋巴结活检中具有一定临床价值,99mTc-Sc对乳腺癌前哨淋巴结检测具有较高的检出率和导向性,能较好的指导手术方案的制定,值得临床推广。      

Comparison of anti-fetal colonic microvillus and anti-CEA antibodies in peroperative radioimmunolocalisation of colorectal cancer

Local recurrence of colorectal cancer may result from failure to assess accurately the extent of tumour at operation. It has been suggested that peroperative radioimmunolocalisation may improve this assessment. The degree to which this is possible has been studied using a hand-held gamma detecting probe and comparing two 125I-labelled monoclonal antibodies to colorectal tumours. The antibodies were to fetal colonic microvillus membrane (FM1D10) and to carcinoembryonic antigen (A5B7). Sixty-nine per cent (9/13) of the FM1D10 and 98% (43/44) of A5B7 labelled tumours took up significant amounts of antibody with a tumour to normal colon ratio of more than 1.5:1. The uptake was significantly better for A5B7 with a median tumour to normal colon ratio of 3.3 (1.1-13.8) compared to 1.85 (0.75-7.7) for FM1D10 (P less than 0.001). The tumour: colon ratio of both antibodies was independent of the serum CEA, Dukes' stage or the degree of histological differentiation. There was a linear correlation for tumour to normal colon ratios between the gamma detecting probe and the same tissue examined in a conventional well counter (correlation coefficient r = 0.78, P less than 0.001). Colorectal tumours demonstrate a rapid and reliable uptake of anti-CEA monoclonal antibody A5B7. This antibody can be detected with a peroperative gamma detecting probe and has the potential to improve the surgeon's appreciation of the extent of tumour and therefore may influence the surgery performed. Detailed clinical studies are now being carried out.     

Detection of sentinel node in breast cancer: pilot study with the imaging probe

The commonly used gamma probes are easy to use but also give rough information when employed in radioisotope-guided surgery. When images are required for exact localization, a gamma camera as well as a probe have to be used. Position-sensitive photomultipliers have contemporaneously allowed high-resolution scintigraphy and miniaturization of gamma cameras. We have assembled a miniature gamma camera with a 1-square-inch field of view and an intrinsic resolution of about 1 mm. When the minicamera is collimated with a large-holed, highly sensitive collimator, it acquires a spatial resolution of 3 mm. This prototype has been tested in the detection of difficult-to-image breast cancer sentinel nodes. Five nodes that had not been found with the usual technique of an Anger camera plus conventional probe were checked with the miniature camera that we named imaging probe: it actually is small enough to be used as a probe and large enough to give an image. One of the five nodes was found and imaged. It was small, disease-free, close to the tumor and probably hidden by the Compton halo around the peritumoral injection site. Our pilot study shows that the imaging probe, although still a prototype, has certain advantages over conventional methods when lymph node localization is required during surgery.     

Use of surgical gamma probe for the detection of lymph node metastases in differentiated thyroid cancer

BACKGROUND: Patients with differentiated thyroid cancer (DTC) after total or near-total thyroidectomy require 131I therapy. After surgery the persistence of lymph node metastases in our series of patients was frequent (30%). Such patients are preferentially treated with radioiodine and shifted to surgical reintervention when the nodal lesions persist after two 131I treatments. AIM: Use of an intraoperative radioactive probe (C-TraK) to allow a more radical surgical approach in thyroid cancer patients submitted to surgery for lymph node metastases. METHODS AND RESULTS: After adequate withdrawal of L-thyroxine suppressive therapy six patients were given high 131I doses followed by post-therapy WBS which demonstrated cervical activity in 5 patients and peri-jugular activity in 1. Surgery with the help of a gamma probe allowed to detect and remove all metastatic nodes. After excision all surgical specimens showed higher radioactive counts with respect to the background. The post-surgical scan showed the disappearance of all areas of 131I uptake. Histology confirmed the presence of metastatic lesions from papillary thyroid cancer. CONCLUSIONS: We conclude that the use of a gamma probe can be successful in patients with metastatic neck lesions resistant to 131I treatment, particularly in patients with nonpalpable lesions.     

Effectiveness of multi-detector row computed tomography in detection of the presence and extent of ductal carcinoma in situ

Background

As ductal carcinoma in situ (DCIS) lesions can spread widely in the ductal-lobular segment, often without palpable tumor, complete resection of the lesion in breast-conserving surgery requires establishment of the precise location and extent of the lesion during preoperative imaging studies. We investigated the potential of multi-detector row computed tomography (MDCT) in detecting and delineating DCIS lesions.

Methods

Overall, 74 patients with 75 DCIS lesions underwent breast MDCT. The size of the DCIS lesion in each patient was measured in the volume rendering images and compared to the size obtained by pathological mapping. The differences between the actual tumor size and that obtained from MDCT (L-Path and L-CT) were calculated, and the relationships between these differences and tumor characteristics were investigated.

Results

DCIS was detected fully or partially in 64 (84.9 %) of 75 lesions, whereas the detection rate of magnetic resonance imaging (MRI) was 90 %. The detection rate was not influenced by comedo/non-comedo status, but the detection rate of higher nuclear grade DCIS lesions tended to be higher than that of low grade lesions (p = 0.089), while the estimated size was also more accurate in the former (p = 0.046). Hormone receptor and Her2 status did not affect MDCT findings.

Conclusion

MDCT is highly effective for detecting DCIS, especially the more aggressive types of DCIS. Moreover, the patient’s position during MDCT imaging is more similar to that during surgery than that during MRI, making MDCT a highly useful presurgical imaging technique for the assessment of DCIS.