Lymphoscintigraphy In Melanoma Research Articles

Sentinel Lymph Node in Breast Cancer, Our First Experience at Nicaragua. Case Report

Morton introduced cutaneous lymphoscintigraphy in melanoma. His results permitted to reproduce sentinel lymph nodes(SLN) in other areas. Krag and Weaver implemented portable gamma radiation detectors in breast cancer. The aim of this article is to describe the first expertise in our hospital using nuclear medicine in breast cancer and the methodological aspects of SLN and reviewing the international literature. Case Report: Female 54 years, no family history of breast cancer. Medical exam detected a mass of 3x2 cm in the upper outer quadrant of the left breast, there is no axillary mass. The Ultrasound: BIRADS IV A. Mammography: BI-RADS V Preoperative Classification: T2N0M0 Tru Cut Biopsy: Invasive carcinoma no type determined. Triple negative. Extension studies were negative. The lymphoscintigraphy done according to international protocol. Methylene blue was used in conjunction with the radiotracer; a periareolar sub dermal injection was given in the operating room. The Surgery performed on the day marked. After localized the scintigraphic hot spots in vivo with the gamma probe Nuclear Lab DGC II. The intraoperative frozen section analysis used with Haematoxylin and Eosin staining. Two SLN reported as metastases Negative. The axillary dissection was deferred. There were no complications. Post-surgical pathologic report showed invasive carcinoma no type determined size 35 x 30 x 28 mm, unifocal. In situ ductal carcinoma and in situ lobular carcinoma unidentified and lympho-vascular unidentified invasion. There is no tumoral extension to the skin. All margins were reported negative.pT2pN0. Conclusion: Each time that a new therapeutic tool is within reach of the oncologic patients, principally when his effectiveness have been demonstrated to long time. It to make true in low income country increase the challenge for her implementation. However, the multidisciplinary effort of the human resources and the help of the technology development of our institutions permeated to jump the hard barrier that this entails, achieving a great achievement to the patients with breast cancer in our country. This first effort is not distant from the reported in the international literature.

Consecutive Case Series of Melanoma Sentinel Node Biopsy for Lymphoseek Compared to Sulfur Colloids

BackgroundSentinel lymph node biopsy (SLNB) is an important adjunct in the staging of patients with melanoma. Preoperative lymphoscintigraphy with radiolabeled isotopes is essential to localize sentinel nodes for removal. Our study compared the effectiveness of Lymphoseek to standard sulfur colloids in patients with melanoma undergoing SLNB. MethodsWe queried our IRB-approved melanoma database to identify 370 consecutive patients who underwent SLNB from 2012 to 2016 with at least 1 y of follow-up. There were 185 patients in each group. Data points included characteristics of the primary melanoma lymphoscintigraphy and SLNB. Student's t-test and chi-square were used to analyze the data with a P value of <0.05 being considered significant. ResultsPatients were equally matched in regard to age, sex, and primary characteristics of their melanoma. In comparison to sulfur colloid, Lymphoseek required lower radiation dosages (P < 0.001), shorter mapping times (P = 0.008), and decreased number of sentinel nodes removed (P = 0.03). There was no difference in the number of patients with positive nodes (P = 0.5). In addition, there were no statistical differences between the two radioactive tracers in regard to the number of patients with false-negative SLNB. ConclusionLymphoseek has the potential to decrease radioactivity and mapping time in patients who need SLNB. With a decrease in the number of nodes removed without loss of sensitivity, there is a potential to avoid unnecessary node removal and thus complications such as lymphedema. Longer follow-up will help to determine if there is any increase in false-negative rates despite fewer nodes removed.

Utility of hybrid SPECT/CT in primary melanoma lymphoscintigraphy: A retrospective case series.

Sentinel lymph node (SLN) biopsy is widely accepted as an important part of staging cutaneous malignant melanoma. Hybrid single photon emission computed tomography and computed tomography (SPECT/CT) may identify additional SLN and provide important information to the surgeon performing SLN biopsy. We report our experience at a major referral centre for melanoma surgery. Retrospective case series of pre-operative sentinel node lymphoscintigraphy for primary melanoma over a consecutive 12-month period. All patients had planar imaging and hybrid SPECT/CT. At least 1 SLN was successfully identified in 82 of 86 eligible patients (95.3%). These 82 patients had 144 SLNs (mean 1.8). There were no patients where the SLN was seen only with SPECT/CT. Additional information was provided by SPECT/CT in 32 patients (39.0%). Histology reports were available for 52 patients, 9 (17.3%) had at least 1 SLN positive for metastatic disease. We achieved a high rate of SLN identification. SPECT/CT was most frequently helpful when the primary melanoma was located in the head, neck and trunk. Routine use of SPECT/CT during lymphoscintigraphy provides important anatomical information and may reduce the false-negative rate.

Reducing perceived pain levels during nonbreast lymphoscintigraphy.

The aim of this study was to quantify the reduction of perceived pain levels during lymphoscintigraphy for melanoma by altering the pH of the Tc-sulfur colloid to near the physiologic value of 7.40. This is an institutional review board- and Food and Drug Administration-approved randomized, double-blinded, prospective crossover trial, registered with clinicaltrials.org. Before beginning the procedure and after signing informed consent, 60 serial enrollees presenting for sentinel lymph node imaging of melanoma of the thorax and appendicular structures completed a questionnaire addressing background information, administered by a research support nurse.An investigator (N.H.) prepared the injections to be used and labeled them such that no one else could discover which injections contained standard-of-care solution and which contained the pH-altered solution (buffered to near pH 7.40 using sodium bicarbonate).After each injection, the enrollee was asked by a research support nurse to quantify the pain of each injection using a scale of 0 to 10. The injection site location (head, thorax, appendicular structures, and other) was also recorded. Sixty subjects were enrolled in the study, of which 57 had complete data. On average, there was a significant mean (SD) decrease of 1.42 (2.17) points (95% confidence interval, 0.85-2.00) on a pain scale of 0 to 10 when the buffered injections were used as compared with the standard-of-care injections (P < 0.0001). Ordering of injections did not significantly affect perceived pain scores. The use of sodium bicarbonate to buffer the pH of Tc-sulfur colloid to near the physiologic value of 7.40 significantly reduced perceived pain levels during nonbreast lymphoscintigraphy.

Transmission Imaging in Lymphoscintigraphy with a 153Gd Flood Source.

Lymphoscintigraphy uses intradermal or interstitial injections of (99m)Tc-labeled tracers to produce images of focal lymph nodes. Because there is little or no anatomic information in the (99m)Tc images, a (57)Co flood source is sometimes used to provide transmission data along with the emission data. The anatomic shadow from the transmission scan generally improves interpretation and surgical planning. However, the (57)Co transmission photons contribute to background on the (99m)Tc images, reducing contrast and signal-to-noise ratio (SNR). SNR is related to lesion detection, and some lymph nodes that would be detected in an emission-only scan might not be detected if acquired with a (57)Co flood source. An alternative to a (57)Co flood source is a (153)Gd flood source, which has primary photon emissions well below the (99m)Tc emission window, allowing the shadow to be acquired in a separate transmission window. Significantly smaller crosstalk from (153)Gd should improve SNR and therefore would be expected to improve lymph node detection. We hypothesized that the use of a (153)Gd flood source would reduce background and improve SNR for these studies. Phantom studies simulating lymphoscintigraphy were performed to compare performance with a (153)Gd flood source, a (57)Co flood source, and no flood source. SNR in the (99m)Tc emission images was measured using a water phantom to simulate patient body and point sources of various activities to simulate nodes and injection site. The encouraging phantom studies prompted use of the (153)Gd flood source in routine clinical breast lymphoscintigraphy, melanoma lymphoscintigraphy, and lymphedema studies. Because emission and transmission data were acquired in separate energy windows, fused planar images of emission and transmission data were available to the physician. SNR was highest with no flood source and was lowest with the (57)Co flood source by a significant margin. SNR with the (153)Gd flood source was similar to that with no flood source on the anterior (transmission) view. SNR was reduced somewhat in the posterior (nontransmission) view because of attenuation of signal by the flood source itself. Minor crosstalk in the (99m)Tc window was observed with the (153)Gd flood source, attributed to simultaneous detection of x-ray photons and gamma-photons. This crosstalk was reduced by introducing thin metal filters to absorb most x-ray photons, at the expense of more attenuation in the posterior view. Unlike with the (57)Co flood source, a usable posterior view (with anatomic shadow derived from the anterior view) was generated with the (153)Gd flood source. Clinical lymphoscintigraphy images with the (153)Gd flood source were of high quality. Interpretation was aided by the ability to control image mixing and brightness and contrast of separate color scales. By producing fused images with reduced crosstalk and improved image quality, a (153)Gd flood source offers advantages over a conventional (57)Co flood source for anatomic shadowing in lymphoscintigraphy. Lymph nodes in emission images have higher SNR, indicating a likely improvement in clinical lesion detection. Separate emission and transmission images provide additional flexibility in image display during interpretation.

The role of hybrid SPECT/CT for lymphatic mapping in patients with melanoma

Lymphoscintigraphy in melanoma provides important information on the dynamic drainage of the primary tumour and the location of the sentinel lymph node (SLN). Unfortunately these images lack anatomical detail. Single positron emission computed tomography/computed tomography (SPECT/CT) provides extremely detailed information on the location of the SLN and its relationship with surrounding structures and it is the aim of this study to report our initial experience with this technology. Thirty-two patients undergoing sentinel lymph node biopsy (SLNB) at our unit between October 2010 and October 2011 were included in this study. In each case, conventional planar lymphoscintigraphy (PL) was followed by SPECT/CT. Images of each patient were reviewed by the operating consultant plastic surgeon and a consultant radiologist. A joint opinion was issued on the number of lymph nodes identified by each imaging modality and whether SPECT/CT influenced surgical approach. Both PL and SPECT/CT detected the SLN in 31/32 patients. There was no significant difference between the number of SLN identified by PL and SPECT (p=0.69). In relation to the true number of SLNs identified intra-operatively by gamma probing and blue dye, there was no statistically significant difference in accuracy between SPECT/CT and PL (p=0.50). SPECT/CT was judged to provide useful anatomical information in all cases. Surgical approach was altered in 12/32 patients and contributed to the detection of SLNs that were positive for metastases. In relation to true SLN number, SPECT/CT was not significantly more accurate than PL. The detailed anatomical information provided by SPECT/CT improved confidence and pre-operative planning in all patients. In select cases, particularly in the head and neck, SPECT/CT overcame the limitations of PL and facilitated the detection and sampling of metastatic nodes.

Functional anatomy of the lymphatics draining the skin: a detailed statistical analysis

Relatively little is known about the functional anatomy of the lymphatic vessels draining the skin. To address this issue, we previously created a three-dimensional computer model of skin lymphatic drainage, using melanoma lymphoscintigraphy (LS) data from 5232 patients. In this study we sought to extend our model by performing a detailed statistical analysis of the mapped LS data to characterize the functional anatomy of the superficial lymphatics without any a-priori spatial bias. We investigated the commonly held assumption that lymphatic drainage is symmetric between the two sides of the body. Results indicated that, with the exception of the lower anterior torso, posterior leg and a small section of the posterior torso, most skin regions with sufficient data showed symmetric drainage. LS data from each symmetric skin region were then reflected to the opposite side of the body to provide an increased LS dataset for subsequent analysis. Cluster analysis was then applied to this reflected LS dataset to group regions of skin that drained in a similar manner. Results defined nine large clusters of skin, largely draining to the dominant axillary, groin, cervical level II and preauricular node fields. Each of the four axillary and groin node fields defined large clusters of skin on the torso, dividing it into regions similar to the historical 'Sappey's lines', although a fifth region of highly ambiguous drainage was also shown in the anterior and posterior center of the torso. Collectively, these results provide important new insights into skin lymphatic drainage, both improving and quantifying our understanding of functional lymphatic anatomy.

Dermal Versus Intraparenchymal Lymphoscintigraphy of the Breast

Dermal and intraparenchymal (IP) injections of radiocolloid have been used for lymphoscintigraphic identification of the sentinel node (SN) in breast cancer. Because of our institute's extensive experience with dermal and IP lymphoscintigraphy for melanoma and breast cancer, we compared patterns of lymphatic migration after both types of injections to identify any differences in drainage patterns or SN identification. Lymphoscintigrams (n = 31) after dermal injections in 30 patients with primary cutaneous melanoma on the breast were compared with lymphoscintigrams after IP injections in 97 consecutive patients with breast cancer. In each case, 400 microCi of filtered 99mTc-sulfur colloid was injected in four quadrants around the tumor or in the biopsy cavity. All lymphoscintigrams were reviewed for patterns of migration and SN location. Five of 31 (16%) dermal injections demonstrated bilateral axillary migration (n = 3) or a suprasternal SN (n = 2), neither of which was found with IP injections. Conversely, 3 of 97 (3%) IP injections demonstrated direct supraclavicular (n = 2) or costal margin (n = 1) nodes (P = .006), neither of which was found with dermal injections. Low axillary SNs were noted after 26 (84%) dermal and 93 (96%) IP injections (P = .037). The incidence of extra-axillary SNs was 26% (8 of 31) in the dermal group but only 5% (5 of 97) in the IP group (P = .0027). There is a significant difference in lymphatic drainage and SN localization between dermal and IP lymphoscintigraphy. This finding has implications for injection techniques when lymphatic mapping of the SN is undertaken to stage a breast carcinoma.

Melanoma lymphoscintigraphy and lymphatic mapping

Lymphoscintigraphy in melanoma has proven to be a reliable method to identify regional lymph nodes at risk for metastases. The first lymph node to drain a cutaneous lesion, the sentinel lymph node (SLN), is predictive of the metastatic status of the regional lymph node group. Lymphatic mapping allows for the identification of the SLN and for selective lymph node sampling. Selective lymph node sampling is less invasive and because only a small quantity of high-risk tissue is submitted for pathological examination, it allows for a more complete and comprehensive pathological examination, which identifies melanoma with up to 100 times the sensitivity of conventional examinations.

Radiopharmaceuticals for Lymphoscintigraphy: Including dusimetry and radiation considerations

The recognition of the importance of lymphoscintigraphy for identification of the sentinel lymph nodes in melanoma and breast cancer plays a significant role in the clinical management of these patients. The widespread clinical acceptance of this technique and the lack of an agreement on which radiopharmaceutical agent has the most ideal properties has resulted in a wide variety of agents being used clinically with other agents under investigation or development. This article reviews some of the physical properties that a radiopharmaceutical agent should possess and discusses in depth commonly used agents and lists some agents under development. This article also discusses the dosimetry and biological effects various radiopharmaceutical agents have for lymphoscintigraphy in melanoma and breast cancer patients. In view of the lack of a consensus agreement on which radiopharmaceutical agent will provide the optimal clinical information this article will provide an overview of potentially useful radiopharmaceutical agents and radiation dosimetry considerations.

Lymphoscintigraphy in Malignant Melanoma and Breast Cancer

Lymphoscintigraphy is the injection of radioactive particles that are then imaged as they pass through lymphatic vessels to their respective lymph nodal drainage basins. Lymphoscintigraphy is receiving increasing interest as a means to stage regional lymph nodes in early stage malignancy. Injection and imaging techniques for performing breast and melanoma lymphoscintigraphy are discussed in this article.

Role of nuclear medicine in melanoma.

Melanoma is a malignant tumour of the melanocytes presenting characteristic metabolic and biological features, which remains a difficult and important issue in oncology. As a functional modality, nuclear medicine offers a variety of possibilities to assist in the clinical management of this disease. A brief survey of currently available techniques is presented for the diagnosis, staging and follow up, either by organ imaging or by using a great spectrum of tumour-seeking radiopharmaceuticals. The role of lymphoscintigraphy in melanoma is emphasized, as well as the supportive role of nuclear medicine in the surgical theater, enabling selective lymph node dissection by the sentinel node procedure and high dose regional chemotherapy by isolated limb perfusion. Although hardly used for metastatic melanoma so far, with all its tumour-seeking approaches nuclear medicine holds a therapeutic potential for this disease as well.

Demonstration of second-tier lymph nodes during preoperative lymphoscintigraphy for melanoma: incidence varies with primary tumor site.

Preoperative cutaneous lymphoscintigraphy (LS) to identify sentinel (first-tier) lymph nodes was performed in 250 consecutive melanoma patients before wide local excision only or wide local excision with sentinel node biopsy. The location of the sentinel nodes was marked on the overlying skin in all patients. Whether or not tracer was present in second-tier lymph nodes on the delayed scans was recorded for each patient and related to the lesion site at which the tracer had initially been injected. For 100 consecutive patients the rate of tracer movement through the lymphatic channels was compared to the incidence of second-tier drainage. Second-tier nodes were visualized in all patients with melanomas on the leg and thigh, and in almost all patients with melanomas on the forearm and hand, but were seen less often in patients with more centrally located melanomas. There was a significant correlation between the rate of lymph flow and the incidence of demonstrable second-tier drainage. The results suggest that the physiology of the lymphatic system varies depending on the origin of the lymphatic vessel. These findings have important implications for application of the sentinel node biopsy technique in individual patients.

CURRENT SURGICAL TECHNIQUES: Lymphoscintigraphy and sentinel node biopsy: a potential new approach in the management of the NO neck

The management of the NO neck in early head and neck cancer, particularly early oral cavity lesions, has been a source of great controversy. Traditionally, many surgeons favored close observation and lymphadenectomy only for palpable lymph node involvement. More recently, with the development of less morbid procedures for dissecting the neck, many surgeons have advised selective cervical lymphadenectomy for patients at risk for the development of metastases. The basic problem generating this controversy is our inability to predict accurately lymph node involvement in a noninvasive fashion. To address this problem, we have extrapolated from available data concepts regarding the use of lymphoscintigraphy in melanoma and breast cancer as a means of determining lymph node involvement. This technique provides an intraoperative confirmation of lymphatic drainage patterns and allows for a minimally invasive sampling of the first, “sentinel” lymph node. The absence of carcinoma in such a lymph node theoretically obviates the need for more extensive neck dissection. The technique also provides the opportunity to identify aberrant patterns of lymphatic drainage. Initial attempts to use this technique in oral cavity tumors should include selective neck dissection as histologic confirmation of the validity of “sentinel” node biopsy. We hope to validate this technique for accessible squamous cell carcinomas of the oral cavity and oropharynx.