Radio-guided Localization Research Articles

Intraoperative Radioguided Localization of an Occult Neuroendocrine Tumor of the Ileum.

We report the intraoperative radioguided localization of an occult well-differentiated neuroendocrine tumor of the ileum in a patient with a known neuroendocrine lymphonodal metastasis in the mesentery. Preoperative imaging included CT, PET/CT with 68 Ga-DOTATOC, and SPECT/CT with 99m Tc-HYNICTOC. These scans revealed morphological and functional properties of the primary tumor localized in the ileum. The day after IV 99m Tc-HYNICTOC injection, the patient underwent surgery, and the target lesion was intraoperatively detected by a collimated handheld γ-probe. Postoperative pathology examination confirmed the target lesion to be a neuroendocrine tumor of the ileum.

Encuesta del Grupo de Trabajo de Cirugía Radioguiada (GTCRG) de la Sociedad Española de Medicina Nuclear e Imagen Molecular (SEMNIM): localización radioguiada de lesiones no palpables de mama con o sin indicación de biopsia selectiva de ganglio centinela: ROLL, SNOLL y semillas de 125I

ObjectiveTo know the current status of the technique of radioguided localisation of non-palpable breast lesions with or without indication for selective sentinel node biopsy -ROLL, SNOLL and 125I seeds- by conducting a national survey developed by the Working Group on Radioguided Surgery (GTCRG) of the Spanish Society of Nuclear Medicine and Molecular Imaging (SEMNIM). Material and methodsIn October 2020, the form was sent in digital format to the different nuclear medicine services in Spain. A response time of 2months with an overtime of 15 days was given. The number of ROLL/SNOLL procedures in each centre and the methodology used were obtained, including important technical details. In addition, a specific section on 125I seeds was included. The results were automatically downloaded into an Excel 2007 spreadsheet for subsequent analysis with the same program. ResultsThe survey was answered by 55 centres; 21 use wire-guided localisation while the remaining 34 use different radioguided surgery techniques (RGS) for the localisation of non-palpable breast lesions, with the results itemized into thirteen sections. The commonly used tracer dose is 111 MBq for the ROLL technique and 222 MBq for the SNOLL technique, with a volume of 0.2ml. The most common protocol is the two-day protocol. 26% of centres performing CRG use 125I seeds for both breast lesion and suspicious/pathological node detection, with the time between implantation and removal being about 3 days, with subsequent radiological control in most cases. ConclusionThe survey shows the relevance of radioguided surgery in the management of breast cancer patients at different stages of the disease, with disparity in the implementation of new techniques and tools, which responds to the multiple healthcare realities of Nuclear Medicine services.

Survey of the Radioguided Surgery Working Group (GTCRG-RGSWG) of the Spanish Society of Nuclear Medicine and Molecular Imaging (SEMNIM): Radioguided localization of non-palpable breast lesions with or without indication for selective sentinel node biopsy: ROLL, SNOLL and 125I seeds

ObjectiveTo know the current status of the technique of radioguided localisation of non-palpable breast lesions with or without indication for selective sentinel node biopsy -ROLL, SNOLL and 125I seeds- by conducting a national survey developed by the Working Group on Radioguided Surgery (GTCRG) of the Spanish Society of Nuclear Medicine and Molecular Imaging (SEMNIM). Material and methodsIn October 2020, the form was sent in digital format to the different nuclear medicine services in Spain. A response time of 2 months with an overtime of 15 days was given. The number of ROLL/SNOLL procedures in each centre and the methodology used were obtained, including important technical details. In addition, a specific section on 125I seeds was included. The results were automatically downloaded into an Excel 2007 spreadsheet for subsequent analysis with the same program. ResultsThe survey was answered by 55 centres; 21 use wire-guided localisation while the remaining 34 use different radioguided surgery techniques (RGS) for the localisation of non-palpable breast lesions, with the results itemized into thirteen sections. The commonly used tracer dose is 111 MBq for the ROLL technique and 222 MBq for the SNOLL technique, with a volume of 0.2 ml. The most common protocol is the two-day protocol. 26% of centres performing CRG use 125I seeds for both breast lesion and suspicious/pathological node detection, with the time between implantation and removal being about 3 days, with subsequent radiological control in most cases. ConclusionThe survey shows the relevance of radioguided surgery in the management of breast cancer patients at different stages of the disease, with disparity in the implementation of new techniques and tools, which responds to the multiple healthcare realities of Nuclear Medicine services.

Preoperative radio-guided localization of lung nodules with I-125 seeds: experience with 32 patients at a single institution.

Videothoracoscopic visualization and/or palpation of pulmonary nodules may be difficult due to their location, small size or limited solid component. The purpose of this study is to present our experience with computed tomography (CT)-guided preoperative localization of pulmonary nodules by percutaneous marking with radio-labelled iodine-125 seeds. A total of 34 pulmonary nodules were marked under CT with the placement of 33 radio-labelled iodine-125 seeds in 32 consecutive patients. All patients underwent biportal video-assisted thoracic surgery (VATS) and in no case was conversion to thoracotomy necessary. A total of 88.2% of the lung nodules were successfully resected. In the remaining 11.8%, migration of the seed to the pleural cavity occurred, although these nodules were still resected during VATS. Of all the patients with pneumothorax after the marking procedure, only one required chest tube placement (3.1%). No major postoperative complications were observed. Preoperative marking of pulmonary nodules with I-125 seeds under CT guidance is a feasible and safe technique that allows their intraoperative identification and resection.

Lung nodule radio-guided localization and uniportal video-assisted thoracoscopic surgery resection.

Since the introduction of lung nodule radio-guided localization, multiport video-assisted thoracoscopic surgery resection has been widely described. To date, only one series has reported the use of uniportal approach. Our objective is to describe the experience of a single institution of lung nodule radio-guided localization and uniportal video-assisted thoracoscopic surgery resection. Retrospective cohort study based on data from medical records of patients between May 2012 and April 2019. Twenty-four patients were included, 13 were women (54.2%) with a median age of 59.5years (range 19 and 81years). Median nodule size was 7mm (range 3-12mm) and 19 (79.2%) patients had single lung nodule. The main indication was sub-centimetric nodule in 22 (91.6%) patients followed by a deep localization in 10 (41.6%) patients and sub-solid nodule in 9 (37.5%) patients. Median surgical time was 102.5min (range 55-160min). 4 (16.6%) patients had malignant neoplasm of the lung, 10 (41.7%) patients had lung metastases and 10 (41.7%) patients had benign lung lesions. The success rate found was 95.8%. Concordance analysis between palpation of the pulmonary nodule and the presence of the nodule in the histopathology was rated as poor, kappa value - 0.71 (P = 0.186) and between the resection of the pulmonary nodule according to the presence of the nodule in the pathology report was rated as good, Kappa value 0.625 (P = 0.001). Lung nodule radio-guided localization and uniportal video-assisted thoracoscopic surgery resection has a similar success rate and complications to those described by multiport video-assisted thoracoscopic surgery resections.

Multimodal CEA-Targeted Image-Guided Colorectal Cancer Surgery using 111In-Labeled SGM-101.

Intraoperative image guidance may aid in clinical decision-making during surgical treatment of colorectal cancer. We developed the dual-labeled carcinoembryonic antigen-targeting tracer, [111In]In-DTPA-SGM-101, for pre- and intraoperative imaging of colorectal cancer. Subsequently, we investigated the tracer in preclinical biodistribution and multimodal image-guided surgery studies, and assessed the clinical feasibility on patient-derived colorectal cancer samples, paving the way for rapid clinical translation. SGM-101 was conjugated with p-isothiocyanatobenzyl-diethylenetriaminepentaacetic acid (DTPA) and labeled with Indium-111 (111In). The biodistribution of 3, 10, 30, and 100 μg [111In]In-DTPA-SGM-101 was assessed in a dose escalation study in BALB/c nude mice with subcutaneous LS174T human colonic tumors, followed by a study to determine the optimal timepoint for imaging. Mice with intraperitoneal LS174T tumors underwent micro-SPECT/CT imaging and fluorescence image-guided resection. In a final translational experiment, we incubated freshly resected human tumor specimens with the tracer and assessed the tumor-to-adjacent tissue ratio of both signals. The optimal protein dose of [111In]In-DTPA-SGM-101 was 30 μg (tumor-to-blood ratio, 5.8 ± 1.1) and the optimal timepoint for imaging was 72 hours after injection (tumor-to-blood ratio, 5.1 ± 1.0). In mice with intraperitoneal tumors, [111In]In-DTPA-SGM-101 enabled preoperative SPECT/CT imaging and fluorescence image-guided resection. After incubation of human tumor samples, overall fluorescence and radiosignal intensities were higher in tumor areas compared with adjacent nontumor tissue (P < 0.001). [111In]In-DTPA-SGM-101 showed specific accumulation in colorectal tumors, and enabled micro-SPECT/CT imaging and fluorescence image-guided tumor resection. Thus, [111In]In-DTPA-SGM-101 could be a valuable tool for preoperative SPECT/CT imaging and intraoperative radio-guided localization and fluorescence image-guided resection of colorectal cancer.

Abstract P1-20-17: Magnetic guided localization for non-palpable breast lesion: A multi-center open-label trial in Japan

Abstract Background: Non-palpable breast lesions represent about 25-35% of all breast cancers diagnosed in developed countries, according to findings based on the evolution of imaging modalities such as MRI, and the uses reliable biopsy techniques such as ultrasound-guided or stereo-guided vacuum assisted biopsy. Wire -guided localization (WGL), radio-guided localization (RGL), and SAVI SCOUT localization (SSL) have been presented as a surgical procedure for non-palpable breast lesion. The reported disadvantages of WGL are related to mechanical stimulation of wire plucking, kinking, and patient discomfort. RGL has issues regarding radioactive licensing, handling, and waste management, and the SSL system requires high start-up costs. To eliminate these problems, we verified the magnetically guided localization (MGL) method for breast lesion localization by means of the combinations of the magnetic probe TAKUMI (ISO13485, Matrix cell Research Institute Inc., Tokyo, Japan) and the guiding-marker system® (Hakko, Tokyo, JAPAN). The TAKUMI is a novel handheld magnetic probe with a permanent magnet and a Hall magnetic sensor for detecting magnetic substances. It was newly developed at the University of Tokyo under a grant from the Japan Agency for Medical Research and Development (AMED). The aim of this study was to evaluate the feasibility and safety of our MGL system. Method: Patients were enrolled in this multi-center, open-label trial from January 2019 to March 2019 at two University Hospitals. The inclusion criteria were age 20 or older female patients who had non-palpable breast lesions, for which breast-conserving surgery or tumor resection was performed. Patients who had a metal allergy, pregnancy, or inflammatory breast cancer were excluded. The guiding-marker system® consists of a stainless-steel hook (φ 0.28 × 10 mm) connected with a nylon thread and an a 21-gauge 10 cm long steel needle.The marker was inserted into the center of the target lesions using ultrasound guidance or stereo guidance within 4 days before surgery. The TAKUMI was used to determine whether the guiding marker was detectable or not before, during, and after the surgical resection of the specimen. The resection rate of the guiding marker, surgical margin status, and re-operation rates were evaluated as the primary outcomes, and the volume and weight of the excised specimen were evaluated as secondary outcomes. The study protocol of the evaluation of magnetic probe system for detecting of non-palpable lesions of the breast was approved by the Institutional Review Board of Nippon Medical School Foundation (CRB3180001) and was registered at https://jrct.niph.go.jp/re (protocol record jRCTs032180422). Written informed consent was obtained from all participants. Results: Forty-one patients were recruited into this study. Thirty-eight patients (92.6%) underwent breast-conserving surgery for breast cancer treatment, and 3 (7.3%) underwent tumor resection for biopsy purposes. All guiding markers were resected during the initial surgical operation. Three out of 38 breast cancer patients (7.9%) were diagnosed as margin positive in frozen section analysis; 2 (5.2%) underwent additional resection during the initial surgery due to the positive margin, and 1 (2.6%) underwent subsequent surgery due to the positive margin on final pathology. Eight patients (21%) underwent boost radiation therapy due to the close margin (&amp;lt;5mm). The median excised specimen weight was 28 g. The range was wide (2-131 g) and depended on the expanse of the lesion. No complications or adverse events were recorded in relation to either the marker placement or the surgery. Conclusion: These data clearly show that MGL is a reliable, accurate, and convenient localization system for non-palpable breast lesions. It is able to eliminate the disadvantages of WGL, RGL, and SSL. Citation Format: Tomoko Kurita, Kanae Taruno, Seigo Nakamura, Hiroyuki Takei, Katsutoshi Enokido, Takashi Kuwayama, Yoko Kanada, Sadako Akashi, Maki Nakai, Meishi Hankyo, Keiko Yanagihara, Takashi Sakatani, Kentaro Sakamaki, Akihiko Kuwahata, Masaki Sekino, Moriaki Kusakabe. Magnetic guided localization for non-palpable breast lesion: A multi-center open-label trial in Japan [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P1-20-17.

EP1.17-25 Radio-Guided Localization of Small Lung Nodules

The widespread use of computed tomography and the obligation of early diagnosis and treatment of small lung nodules have increased in recent years. There are few localization techniques, ROLL seems one of the safest and most effective. The purpose of this study is to report our experience. We have retrospectively reviewed all patients with undetermined lung nodule that underwent radio-guided localization. The aim of the study was to evaluate the efficacy of the ROLL for the diagnosis and treatment of small lung nodules. The morning of the surgery, Tc99 macroaggregated albumin was injected guided by computer tomography. Afterwards a SPECT-CT was performed to check the correct localization of the tracer and the patient was brought into the operating room. During the surgery a gamma probe connected to a gamma ray was introduced and the lung surface scanned. After detecting the higher value area, a lung resection was performed and the lung is rescanned to check the residual activity (less than 10%). Between November 2011 and February 2019, 30 patients (22 male and 8 female) underwent radiotracer injection followed by lung resection surgery in our institute. Mean age was 66,3 years (range 52 to 76 years). The main complication was pneumothorax (9 patients, 30%), but no patient required chest drainage. There was one non-complicated aortic puncture. There were no other complications. The mean nodule size was 9,07mm +/- 4,35mm and the mean visceral pleural distance was 19,6mm +/-16,27mm. By radiology characteristics, 16 were ground glass opacities, 10 solid nodules and 4 partially solid nodules. The lesions were well detected in 100% cases. They were resected by wedge resection in all the cases. The final pathologic diagnosis confirmed 12 lung adenocarcinoma (6 lepidic growth adenocarcinoma, 3 adenocarcinoma in situ, 2 solid adenocarcinomas, 1 minimally invasive adenocarcinoma), 12 lung metastasis, 2 atypical adenomatous hyperplasia, 2 inflammatory nodules, 1 squamous carcinoma and 1 hamartoma. Clean margins were obtained in 28 patients (93,3%). There were not intraoperative and postoperative complications secondary to the procedure. The radio-guided localization is a simple, easy and safe procedure for the diagnosis and treatment of small lung nodules. There were not problems of radiotracer lung diffusion and misplacement.

Comparison of Radio-guided Occult Lesion Localization (ROLL) and Magnetic Occult Lesion Localization (MOLL) for Non-palpable Lesions: A Phantom Model Study

BackgroundLocalization of nonpalpable breast cancers can be achieved with several techniques. We sought to compare radio-guided localization (ROLL) and magnetic tracer localization (MOLL) techniques by using a phantom model we previously developed, which can provide an accurate simulation for excision of nonpalpable breast lesions. Materials and MethodsWe designed 20 phantom models (10 MOLL, 10 ROLL group) for localization. A handheld gamma probe for the ROLL group and a manual magnetometer (SentiMag) for the MOLL group were used to test the ability of the modality to detect olives in turkey breasts. The excision time for each procedure, specimen size, and weight of the specimens removed from the turkey breasts were recorded. ResultsBoth techniques resulted in 100% retrieval of the lesions. There was no difference between the groups in the duration of operative excision, specimen weight, or specimen volume. ConclusionThis experimental trial found similar success rates for ROLL and MOLL in localization of occult lesions using the turkey breast phantom model. MOLL can be performed in clinics without the need for a nuclear medicine team and radiation safety procedures.

Radio-guided and clip-guided preoperative localization for malignant microcalcifications offer similar performances in breast-conserving surgery.

Obtaining a tailored breast resection is challenging in microcalcifications detected on screening mammography, and an accurate localization is required. The aim of this study was to compare the efficacy of radio-guided localization (ROLL) versus ultrasound localization of a titanium clip with collagen (TCC) in terms of clear margins, re-intervention rates, excess of resected breast tissue, and operative times in pure malignant microcalcifications detected on screening mammography. Two hundred and twenty-one consecutive patients with malignant microcalcifications detected on screening mammography from a tertiary breast unit were reviewed: 177 patients were localized by TCC and 44 patients by stereotactic ROLL. A propensity score-matched analysis was performed, followed by a logistic regression model, to avoid selection bias. Adequacy of resection was expressed as the calculated resection ratio considering lesion size. No differences were found in clear margins with ROLL versus TCC (77.3% vs 81.8%, adjusted OR 2, P=0.27). Re-operation rates were similar, being 11.3% with ROLL and 7.4% with TCC (P=0.627). Mean resection volume was 46.2cm3 with ROLL versus 54.2cm3 with TCC (P=0.222). Adjusted mean calculated resection ratio was 1.8 with ROLL and 2.1 with TCC (P=0.38). Surgery time was longer with TCC compared to ROLL (69.6 vs 52.7minutes, P<0.0001). ROLL and TCC are equally effective to excise malignant microcalcifications with clear margins, providing similar re-intervention rates and resection volumes.

Radio-guided vs clip-guided localization of nonpalpable mass-like lesions of the breast from a screened population: A propensity score-matched study.

An accurate localization is mandatory to tailor breast lumpectomy in nonpalpable cancers. The aim of this study was to compare radio-guided localization (ROLL) vs ultrasound localization of a titanium clip with collagen (TCC) in nonpalpable mass-like breast cancers. Two hundred seventy-three consecutive patients were reviewed: 64 patients were localized by TCC and 209 patients by ROLL. Propensity score-matched analysis was performed. Margin status and reintervention rates were compared. Adequacy of resection was expressed as the calculated resection ratio (CRR) considering lesion size. Loco-regional and distant recurrence rates were assessed with ROLL vs TCC. No differences were found with ROLL vs TCC in clear margins (90.6% vs 89.1%; odds ratio, 0.74; P = 0.64) or reoperations (6.7% vs 1.6%; P = 0.529). ROLL allowed more tailored resections compared with TCC (adjusted CRR, 1.7 vs 2.7; P = 0.0008), particularly in lesions with associated extensive intraductal component (CRR, 3.0 vs 4.5; P = 0.017). Loco-regional recurrence occurred in 1.9% of ROLL patients vs 3.2% of TCC cases (P = 0.628). ROLL and TCC are equally effective to excise nonpalpable mass-like breast cancers with clear margins, providing similar loco-regional control. However, ROLL allows more tailored breast resections, particularly in lesions with the associated extensive intraductal component.

Assessment of Ultrasound / Radio-guided Occult Lesion Localization in Non-palpable Breast Lesions.

Objective(s):Controversy exists about the localization of non-palpable breast lesions. In many countries, the gold standard for the diagnosis of these lesions is needle localization due to its accuracy. This study sought to compare the ultrasound- and radio-guided occult lesion localization (ROLL) as a simple method with the conventional procedures in terms of their diagnostic power.Methods:This study was conducted on 94 patients with non-palpable breast lesions detected by ultrasonography and localized by the combination of ultrasonography and using radiopharmaceuticals. One to ten hours prior to surgery, 0.1-0.2 ml (equivalent to 0.5-1 mCi) of Tc-99m-phytate was injected to the lesion under the guidance of ultrasonography. Then, the lesion was localized using a hand-held gamma probe, and excision of the lesion was performed according to its radioactivity signal. Data analysis was performed using SPSS, version 16.Results:Benign and malignant pathologic results were observed in 77 (81.9%) and 17(18.1%) of the patients, respectively, and the mean volume of the excised tissue was 26.29±27 mm³. 79 patients had a solitary lesion (84%), 55 in the left breast (58.5%) and 39 in superolateral quadrant (41.5%). The mean size of the lesions was 15.7 mm in diameter (ranging from 4 to 34 mm). Additionally, there was a need to secondary surgery in 3 (3.2%) patients and inappropriate localization in 6 (6.4%) patients (subcutaneous or intra-ductal spread of radiodrug).Conclusion:Combination of ultrasound- and radio-guided localization methods for localizing non-palpable breast lesions is a simple and acceptable method for localization with no significant complications. For radio-drug spread and subsequent excessive excised tissue volume, subcutaneous and intra-ductal lesions are not suitable indication for ROLL.

Advances in radioguided surgery in oncology.

The sentinel lymph node (SLN) biopsy is probably the most well-known radioguided technique in surgical oncology. Today SLN biopsy reduces the morbidity associated with lymphadenectomy and increases the identification rate of occult lymphatic metastases by offering the pathologist the lymph nodes with the highest probability of containing metastatic cells. These advantages may result in a change in clinical management both in melanoma and breast cancer patients. The SLN evaluation by pathology currently implies tumor burden stratification for further prognostic information. The concept of SLN biopsy includes pre-surgical lymphoscintigraphy as a "roadmap" to guide the surgeon toward the SLNs and to localize unpredictable lymphatic drainage patterns. In addition to planar images, SPECT/CT improves SLN detection, especially in sites closer to the injection site, providing anatomic landmarks which are helpful in localizing SLNs in difficult to interpret studies. The use of intraoperative imaging devices allows a better surgical approach and SLN localization. Several studies report the value of such devices for excision of additional sentinel nodes and for monitoring the whole procedure. The combination of preoperative imaging and radioguided localization constitutes the basis for a whole spectrum of basic and advanced nuclear medicine procedures, which recently have been encompassed under the term "guided intraoperative scintigraphic tumor targeting" (GOSTT). Excepting SLN biopsy, GOSTT includes procedures based on the detection of target lesions with visible uptake of tumor-seeking radiotracers on SPECT/CT or PET/CT enabling their subsequent radioguided excisional biopsy for diagnostic of therapeutic purposes. The incorporation of new PET-tracers into nuclear medicine has reinforced this field delineating new strategies for radioguided excision. In cases with insufficient lesion uptake after systemic radiotracer administration, intralesional injection of a tracer without migration may enable subsequent excision of the targeted tissue. This approach has been helpful in non-palpable breast cancer and in solitary pulmonary nodules. The introduction of allied technologies like fluorescence constitutes a recent advance aimed to refine the search for SLNs and tracer-avid lesions in the operation theatre in combination with radioguidance.

Assessment of Radio-Guided Occult Lesion Localization Associated with Sonography in Nonpalpable Breast Lesions

Background: Several methods are in use for localization of non-palpable breast lesions prior to excision. The most common is wire-guided localization which is fraught with difficulties and possible complications. Radio-guided localization of non-palpable lesions (ROLL) is a relatively new method which has been never used in our country before. We have for the first time investigated its diagnostic value for localization of non-palpable breast lesions in a teaching hospital in Iran. Methods: In this study, 42 patients with non-palpable breast lesions, detected by ultrasonography, underwent radio-guided localization. Phytate-Tc-99m was injected into the lesion under the guidance of ultrasonography, 1-2 hours before surgery. Excision of the lesion was performed according to radioactivity signal of lesion, detected by a hand-held gamma probe during surgery. After total excision, the resection bed was explored by gamma probe to detect any residual activity. So if there was no radioactivity signal, the excision was regarded as complete. The data of ultrasonographic characteristics, localization and excision procedure, complications, margin status and tissue volume were analyzed by SPSS 16. Results: Pathologic results were benign in 90.5% and malignant in 9.5% of patients. Post-operative margin of lesion was clear in 100% of patients. No margin involvement was reported. Mean duration of localization and surgical procedure was 1.80 0.42 and 26.78 8.10 minutes, respectively. Fault in localization took place in 4 patients (9.5%) and there was a need to secondary surgery in 1 patient (2.4%). Patients satisfaction level about post-operative cosmetic results was excellent in 33.3% and good in 66.6% of patients. Mean excised tissue volume was 28.59 27.96 cm in all patients and 23.54 23.46 cm, in patients without fault of localization. Conclusions: Radio-guided localization of non-palpable breast lesions is an acceptable method because of technical facilitation, accurate localization and complete excision with limited complications. So it can be recommended as an alternative method for wire-guided localization.

P1.03-037 Radio-Guided Localization and Resection of Small or Ill-Defined Pulmonary Lesions

P1.03-037 Radio-Guided Localization and Resection of Small or Ill-Defined Pulmonary Lesions

A bird in the hand is worth two in the bush: the choice of localization technique for non-palpable solitary pulmonary nodule.

We read with interest the comments of Martin-Ucar et al . (1) and Bedetti et al . (2) about our previous paper describing the radioguided localization technique of non-palpable solitary pulmonary nodule (SPN) or ground glass opacities (GGO) to identify and to resect them by video-assisted thoracoscopic surgery (VATS) (3).

Commentary on the article "Radioguided video-assisted resection of non-palpable solitary pulmonary nodule/ground glass opacity: how to do it".

The article describes the radioguided localization technique of small lesions (maximum nodule diameter 99m technetium macro-aggregate albumin diluted with iodized contrast medium. This allows the stability of the radiotracer in the lung for up to 18 hours for an optimal planning of the surgical resection. A CT scan was performed to confirm the precise staining. Then a VATS with three ports was performed and the gamma detector was inserted inside the chest to localize the tracer and the parenchyma was grasped in its correspondence. After a double check of the tracer’s position with the gamma detector, the resection was performed and the sample was sent for histologic examination (frozen section). In case of diagnosis of lung cancer, a VATS lobectomy was performed.

Current status of ultrasound-guided surgery in the treatment of breast cancer.

The primary goal of breast-conserving surgery (BCS) is to obtain tumour-free resection margins. Margins positive or focally positive for tumour cells are associated with a high risk of local recurrence, and in the case of tumour-positive margins, re-excision or even mastectomy are sometimes needed to achieve definite clear margins. Unfortunately, tumour-involved margins and re-excisions after lumpectomy are still reported in up to 40% of patients and additionally, unnecessary large excision volumes are described. A secondary goal of BCS is the cosmetic outcome and one of the main determinants of worse cosmetic outcome is a large excision volume. Up to 30% of unsatisfied cosmetic outcome is reported. Therefore, the search for better surgical techniques to improve margin status, excision volume and consequently, cosmetic outcome has continued. Nowadays, the most commonly used localization methods for BCS of non-palpable breast cancers are wire-guided localization (WGL) and radio-guided localization (RGL). WGL and RGL are invasive procedures that need to be performed pre-operatively with technical and scheduling difficulties. For palpable breast cancer, tumour excision is usually guided by tactile skills of the surgeon performing "blind" surgery. One of the surgical techniques pursuing the aims of radicality and small excision volumes includes intra-operative ultrasound (IOUS). The best evidence available demonstrates benefits of IOUS with a significantly high proportion of negative margins compared with other localization techniques in palpable and non-palpable breast cancer. Additionally, IOUS is non-invasive, easy to learn and can centralize the tumour in the excised specimen with low amount of healthy breast tissue being excised. This could lead to better cosmetic results of BCS. Despite the advantages of IOUS, only a small amount of surgeons are performing this technique. This review aims to highlight the position of ultrasound-guided surgery for malignant breast tumours in the search for better oncological and cosmetic outcomes.

A low cost training phantom model for radio-guided localization techniques in occult breast lesions.

Radio-guided localization (RGL) for identifying occult breast lesions has been widely accepted as an alternative technique to other localization methods, including those using wire guidance. An appropriate phantom model would be an invaluable tool for practitioners interested in learning the technique of RGL prior to clinical application. The aim of this study was to devise an inexpensive and reproducible training phantom model for RGL. We developed a simple RGL phantom model imitating an occult breast lesion from inexpensive supplies including a pimento olive, a green pea and a turkey breast. The phantom was constructed for a total cost of less than $20 and prepared in approximately 10 min. After the first model's construction, we constructed approximately 25 additional models and demonstrated that the model design was easily reproducible. The RGL phantom is a time- and cost-effective model that accurately simulates the RGL technique for non-palpable breast lesions. Future studies are warranted to further validate this model as an effective teaching tool.

Radio-Guided Localization and Resection of Small or Ill-Defined Pulmonary Lesions

Screening programs have increased the identification of small or indistinct pulmonary lesions that are difficult to localize. We report our experience in their preoperative localization by radiotracer and resection. Patients with pulmonary nodules of subsolid morphology or smaller than 1 cm, deeper 1 cm below the visceral pleura, or both underwent computed tomography (CT)-guided injection of radiotracer technetium 99m macroaggregates in the vicinity of the lesion. During the operation, a handheld gamma probe was used to detect the hot spot where the radioactive tracer was localized, and this area was resected. From November 2007 to May 2013, 112 patients (58 men; median age 62 years) underwent preoperative radiotracer injection with a successful marking in all patients. Adverse events included 33 (29.4%) pneumothoraces (one requiring chest tube placement), 23 (20.5%) parenchymal hemorrhage suffusions, and 1 (0.9%) allergic reaction to contrast medium. In all cases except two, the gamma probe revealed pulmonary lesions. Overall, 123 pulmonary nodules were localized and resected. The mean distance from the pleura was 12 mm (range, 0 to 39 mm). Pulmonary resection was performed by thoracoscopy in 70 (62.5%) cases, thoracotomy in 36 (32.1%), and conversion of thoracoscopy to thoracotomy in 6 (5.4%). The mean nodule size was 9 mm (range, 3 to 24 mm). Histology showed 14 (11.4%) benign lesions and 109 (88.6%) malignant lesions (85 primary lung cancers and 24 metastases). Radiotracer localization of pulmonary lesions is a simple and feasible procedure with a high rate of success. Optimal candidates are patients with suspicious-looking nodules detected by screening or incidental CT resulting frm the high rate of nonsolid morphology and small size.