Lymphoscintigraphy for Imaging of the Lymphatic Flow Disorders.

Lymphoscintigraphy has introduced with the great advantage for diagnostic imaging of the lymphatic flow disorders. Lymphoscintigraphy can be performed in patients of any age, including neonates, and even in patient in critical conditions. The procedure is quite simple, and it needs only subcutaneous injection of small amounts of radiotracers. From subcutaneous tissue the radiotracer is taken by the lymphatic vessels and gives off energy in the form of gamma radiation detected by a gamma camera. Radiotracers rarely cause the allergic reaction and can be administered to the patients with allergy to iodine contrast media. Comparing with the Lipiodol, radiotracers cannot cause pulmonary embolism; therefore, it is safe for the patients with respiratory dysfunction. The objective of this article is to describe the indication, technique, equipment, pitfalls, safety, and effectiveness of lymphoscintigraphy for imaging of the lymphatic flow disorders.

Aportación de la tomografia por emisión de fotón Simple/tomografía computadorizada a la biopsia selectiva del ganglio centinela en pacientes diagnosticados de melanoma de cabeza y cuello / Role of SPECT-CT in sentinel lymph node biopsy in patients diagnosed with head and neck melanoma

Objetivo. Valorar la aportación de la SPECT-TC a la biopsia selectiva del ganglio centinela (GC) en la correcta localización anatómica de este, en pacientes diagnosticados de melanoma cutáneo de cabeza y cuello. Material y métodos. Estudio retrospectivo entre febrero de 2010 y junio de 2013 que incluyó 22 pacientes consecutivos diagnosticados de melanoma cutáneo de cabeza y cuello (9 mujeres y 13 hombres), con una edad media de 55 años y criterios de inclusión de biopsia selectiva del GC. A todos ellos se les realizó una linfogammagrafía preoperatoria tras la inyección pericicatricial de nanocoloides de albúmina marcados con 99mTc, y posteriormente se obtuvieron imágenes planares sectoriales del lugar de inyección y de cuerpo completo, así como SPECT-TC. Resultados. La tasa de detección del GC fue del 91% (20 de 22 pacientes) para la linfogammagrafía planar y del 95,4% (21 de 22 pacientes) para SPECT-TC. En 14 de 22 pacientes la SPECT-TC mostró información relevante sobre la localización del GC modificando la vía de abordaje quirúrgica, siendo el impacto clínico de un 63,6%. En un 9,1% de los pacientes el GC fue positivo para metástasis de melanoma. Conclusión. La SPECT-TC proporciona información anatómica relevante sobre la localización del GC y detecta un mayor número de ganglios linfáticos que la linfogammagrafía. Se recomienda el uso rutinario de SPECT-TC en la linfogammagrafía del melanoma de cabeza y cuello para optimizar la localización y el número de GC en esta área (AU)

Objective. Assess the role of SPECT-CT in sentinel lymph node (SLN) biopsy in the accurate anatomical location of the SNL in patients with cutaneous head and neck melanoma. Material and methods. A retrospective study was conducted from February 2010 to June 2013 on 22 consecutive patients with a diagnosis of cutaneous head and neck melanoma (9 female, 13 male), with a mean age of 55 years old and who met the inclusion criteria for SLN biopsy. Patients underwent preoperative scanning after peri-scar injection of 99mTc-labeled-nanocolloid. Planar images of the injection-site, whole-body, and SPECT-CT scanning were acquired. Results. Detection rate of SLN reached up to 91% (20/22 patients) by planar lymphoscintigraphy and 95.4% (21/22 patients) by SPECT-CT. SPECT-CT provided an accurate location of SLN in 14/22 patients, enabling to improve the surgical approach (clinical impact: 63.6%). SLN was positive for metastatic cells in 9.1% patients. Conclusion. SPECT-CT provides detailed anatomical SLN location and allows detecting a higher number of SLN than planar lymphoscintigraphy. Routine use of SPECT-CT is recommended in order to optimise the SLN detection and location in patients with head and neck melanoma (AU)

A New Portable Hybrid Camera for Fused Optical and Scintigraphic Imaging: First Clinical Experiences.

PURPOSE: Although portable gamma cameras (PGCs) have been helpful to depict sentinel nodes (SNs), sometimes nuclear physicians or surgeons have difficulties to interpret PGC images because of the lack of anatomical information. The aim of the present study was to develop and clinically test the prototype of a new portable hybrid camera (PHC), which adds optical to γ-imaging. METHODS: In 2 hospitals, the existing PGC (Sentinella S102; Oncovision) was upgraded with an optical module (BB2-08S2C-25; Point Grey Research) to build a PHC. Preoperative PHC overview images (positioned at 15 cm distance) and close-up image (position at <5 cm distance) were obtained from 25 patients (12 melanoma, 2 oral cavity, and 11 breast cancer) after conventional lymphoscintigraphy. Errors in the optical image coregistration were evaluated with a 5-mm accuracy for each patient. RESULTS: Conventional lymphoscintigraphy and the close-up PHC images depicted 55 SNs in total. In the PHC overview images, the optical module offered fused optical and γ-imaging indicating the image field of view and anatomical SN locations. Average optical image coregistration errors were 1.0 cm (range, 0-2.0 cm). CONCLUSIONS: Fused optical and γ-imaging with the prototype PHC is technically feasible and helpful for the image interpretation. The optical image visualizes the γ-image field of view, enabling SN localization in an anatomical context in a preoperative setting; however, for the operating room, the use of its optical component needs to be additionally adjusted.

Manejo terapéutico del linfedema de pene subagudo y secundario a erisipela mediante colgajos cutáneos / Therapeutic approach of subacute penile lymphoedema secondary to erysipela by means of cutaneous flaps

Presentamos la revisión clínica de un paciente de 38 años remitido a nuestro centro por linfedema de pene secundario a infección por Streptococcus pyogenes (erisipela) de 6 meses de evolución que como secuela presenta edema de consistencia gomosa sin lesiones dérmicas asociadas limitado al pene que imposibilita las relaciones sexuales y dificulta el vaciado vesical. La linfogammagrafía no evidenció acúmulo del radiofármaco a nivel genital mientras que la RMN mostró marcado engrosamiento cutáneo y subcutáneo alrededor de cuerpos cavernosos y glande con predominio del tejido fibroso. Se realizó resección quirúrgica del tejido fibroso cubriendo el defecto con colgajos laterales de piel peneana. El estudio anatomopatológico con utilización de marcadores específicos CD-31 y D2-40 confirmó la presencia de linfáticos infiltrados. El postoperatorio cursó sin complicaciones, mostrando aspecto cosmético satisfactorio sin presencia del edema ni síntomas urinarios y recuperando la función sexual a los 6 meses (AU)

Clinical review of a 38 years old patient referred to our hospital with penile lymphoedema secondary to a Streptococcus pyogenes (erysipela) infection 6 month ago. Physical exam revealed an uncircumcised penis with a soft consistency edema and no skin lesions. The patient was unable to maintain intercourse and had urine dripping caused by obliteration of the foreskin. Lymphogammagraphy revealed the absence of drug accumulation at genital area. MRI showed skin strengthening around the cavernous corpora and glans with fibrous tissue predominance. We performed a surgical resection of the fibrous tissue with lateral penis cutaneous flaps. There were no complications during the intervention and the post-operative period. The pathology report revealed the presence of lymphatic vessels with specific coloring DC-31 and D2-40. Six months after the intervention we observed an absence of edema with satisfactory cosmetic appearance, without urinary symptoms, and patient was able to maintain erections and perform intercourse (AU)

Biopsia selectiva de ganglio centinela de melanoma en niños. Serie de casos / Sentinel lymph node biopsy in paediatric melanoma. A case series

La incidencia del melanoma en la edad pediátrica es baja, siendo particularmente raro en menores de 10 años. No obstante, se ha constatado un aumento de la misma con un incremento promedio del 2% por año. Al igual que en los adultos, la afectación ganglionar es el factor pronóstico más relevante, por ello es fundamental la realización de la biopsia selectiva del ganglio centinela (BSGC). Presentamos 3 casos de pacientes en edad pediátrica de 3, 4 y 8 años, en los que se realizó BSGC, por melanoma maligno. La edad pediátrica confiere una mayor dificultad técnica al estudio linfogammagráfico por la escasa colaboración del paciente, precisando en algunos casos sedación superficial para su realización y pudiéndose adquirir únicamente en la mayoría de los casos imágenes sectoriales. Solamente en la paciente de mayor edad pudo practicarse SPECT/TC complementario. En nuestros casos la BSGC fue eficaz para poder seleccionar el tratamiento quirúrgico menos invasivo reduciendo así la morbilidad (AU)

The incidence of melanoma in children is uncommon, being particularly rare in children under 10 years-old. However, this disease is increasing by a mean of 2% per year. As in adults, the lymph node status is the most important prognostic factor, crucial to performing the selective sentinel lymph node biopsy (SLNB). We report 3 cases of paediatric patients of 3, 4 and 8 years-old, in which SLNB was performed for malignant melanoma. Paediatric age implies greater technical difficulty to the scintigraphy scan due to poor patient cooperation, with mild sedation required in some cases, and only being able to acquire planar images in other cases. SPECT/CT was only performed in the oldest patient. In our cases, SLNB was useful for selecting the least invasive surgery in order to reduce morbidity (AU)

Sentinel node approach in prostate cancer.

In general terms, one of the main objectives of sentinel lymph node (SLN) biopsy is to identify the 20-25% of patients with occult regional metastatic involvement. This technique reduces the associated morbidity from lymphadenectomy, as well as increasing the identification rate of occult lymphatic metastases by offering the pathologist those lymph nodes with the highest probability of containing metastatic cells. Pre-surgical lymphoscintigraphy is considered a "road map" to guide the surgeon towards the sentinel nodes and to ascertain unpredictable lymphatic drainages. In prostate cancer this aspect is essential due to the multidirectional character of the lymphatic drainage in the pelvis. In this context the inclusion of SPECT/CT should be mandatory in order to improve the SLN detection rate, to clarify the location when SLNs are difficult to interpret on planar images, to achieve a better definition of them in locations close to injection site, and to provide anatomical landmarks to be recognized during operation to locate SLNs. Conventional and laparoscopic hand-held gamma probes allow the SLN technique to be applied in any kind of surgery. The introduction and combination of new tracers and devices refines this technique, and the use of intraoperative images. These aspects become of vital importance due to the recent incorporation of robot-assisted procedures for SLN biopsy. In spite of these advances various aspects of SLN biopsy in prostate cancer patients still need to be discussed, and therefore their clinical application is not widely used.

Portable gamma camera guidance in sentinel lymph node biopsy: prospective observational study of consecutive cases.

INTRODUCTION: Sentinel lymph node biopsy is the most important tool available for node staging in patients with melanoma. OBJECTIVES: To analyze sentinel lymph node detection and dissection with radio guidance from a portable gamma camera. To assess the number of complications attributable to this biopsy technique. METHODS: Prospective observational study of a consecutive series of patients undergoing radioguided sentinel lymph node biopsy. We analyzed agreement between nodes detected by presurgical lymphography, those detected by the gamma camera, and those finally dissected. RESULTS: A total of 29 patients (17 women [62.5%] and 12 men [37.5%]) were enrolled. The mean age was 52.6 years (range, 26-82 years). The sentinel node was dissected from all patients; secondary nodes were dissected from some. In 16 cases (55.2%), there was agreement between the number of nodes detected by lymphography, those detected by the gamma camera, and those finally dissected. The only complications observed were seromas (3.64%). No cases of wound dehiscence, infection, hematoma, or hemorrhage were observed. CONCLUSIONS: Portable gamma-camera radio guidance may be of use in improving the detection and dissection of sentinel lymph nodes and may also reduce complications. These goals are essential in a procedure whose purpose is melanoma staging.

Ganglio centinela en melanoma y cáncer de mama. Consideraciones actuales / Sentinel node in melanoma and breast cancer. Current considerations

Los principales objetivos de la biopsia del ganglio centinela (GC) es evitar linfadenectomías innecesarias e identificar el 20-25% de pacientes que presentan enfermedad ganglionar regional clínicamente oculta. Esta técnica minimiza la morbilidad asociada a la linfadenectomía y aumenta también la tasa de identificación de metástasis linfáticas ocultas al ofrecer al patólogo aquel o aquellos ganglios con mayor probabilidad de contener células tumorales procedentes del tumor primario. La linfogammagrafía prequirúrgica se considera como un «mapa de carreteras» para guiar al cirujano hacia los GC y para la localización de patrones de drenaje impredecibles. Las ventajas del SPECT/TC incluyen un índice global de detección del GC superior a las imágenes planares, la capacidad para detectar ganglios centinelas en estudios convencionales difíciles de interpretar, mejor definición de los mismos en localizaciones cercanas a la inyección y una mejor localización anatómica. Estas ventajas pueden provocar un cambio en el manejo clínico-quirúrgico del paciente tanto en melanoma como en cáncer de mama. La correcta evaluación anatomopatológica del GC supone una estratificación de la carga tumoral y su posterior implicación pronóstica. La utilización de la imagen intraoperatoria permite al cirujano adaptar las marcas previamente hechas a la incisión quirúrgica planeada y confirmar la localización exacta del GC. Diversos estudios han demostrado el valor añadido de la utilización de estos dispositivos, al permitir la resección de GC adicionales y monitorizar el proceso quirúrgico. Nuevas técnicas, utilizando trazadores híbridos o fluorescentes, se están desarrollando en la actualidad (AU)

The main objectives of sentinel node (SN) biopsy is to avoid unnecessary lymphadenectomies and to identify the 20-25% of patients with occult regional metastatic involvement. This technique reduces the associated morbidity from lymphadenectomy and increases the occult lymphatic metastases identification rate by offering the pathologist the or those lymph nodes with the highest probability of containing metastatic cells. Pre-surgical lymphoscintigraphy is considered a 'road map' to guide the surgeon towards the sentinel nodes and to localize unpredictable lymphatic drainage patterns. The SPECT/CT advantages include a better SN detection rate than planar images, the ability to detect SNs in difficult to interpret studies, better SN depiction, especially in sites closer to the injection site and better anatomic localization. These advantages may result in a change in the patient's clinical management both in melanoma and breast cancer. The correct SN evaluation by pathology implies a tumoral load stratification and further prognostic implication. The use of intraoperative imaging devices allows the surgeon a better surgical approach and precise SN localization. Several studies reports the added value of such devices for more sentinel nodes excision and a complete monitoring of the whole procedure. New techniques, by using fluorescent or hybrid tracers, are currently being developed (AU)

Evaluación de la eficacia en la detección del ganglio centinela en el cáncer de mama: evolución cronológica e influencia de la incorporación de una gammacámara portátil intraoperatoria / Evaluation of the efficacy of sentinel node detection in breast cancer: chronological course and influence of the incorporation of an intra-operative portable gamma camera

Objetivo. Determinar el porcentaje de identificación global del ganglio centinela (GC) en el cáncer de mama, la evolución cronológica de este parámetro y la influencia de la introducción de una gammacámara portátil. Material y métodos. Estudio retrospectivo a partir de una base de datos prospectiva de 754 pacientes a las que se realizó biopsia selectiva del GC de forma consecutiva entre enero de 2003 y diciembre de 2011. La técnica fue mixta en periodo inicial y posteriormente con radiotrazador administrado intra-peritumoralmente. Hasta octubre de 2009 la exéresis del GC fue guiada por sonda y a partir de esta fecha se introdujo una gammacámara portátil para la detección intraoperatoria. Resultados. Se ha biopsiado el GC en 725 de 754 pacientes, siendo por tanto la eficacia global del 96,2%. Según el año de intervención quirúrgica los porcentajes de identificación han sido del 93,5% en 2003, del 88,7% en 2004, del 94,3% en 2005, del 95,7% en 2006, del 93,3% en 2007, del 98,8% en 2008, del 97,1% en 2009 y del 99,1% en 2010 y 2011. Existe una diferencia de proporciones entre el porcentaje de identificación antes y después de la incorporación de la gammacámara portátil del 4,6% que es estadísticamente significativa (IC 95% de la diferencia 2-7,2% con una p asociada de 0,0037). Conclusiones. El porcentaje de identificación global se halla por encima del nivel recomendado por las directrices actuales. Cronológicamente se constata elevación de este parámetro a lo largo del periodo estudiado. Los datos apuntan a que la incorporación de una gammacámara portátil ha tenido un papel en ello (AU)

Aim. To define the sentinel node identification rate in breast cancer, the chronological evolution of this parameter and the influence of the introduction of a portable gamma camera. Material and methods. A retrospective study was conducted using a prospective database of 754 patients who had undergone a sentinel lymph node biopsy between January 2003 and December 2011. The technique was mixed in the starting period and subsequently was performed with radiotracer intra-peritumorally administered the day before of the surgery. Until October 2009, excision of the sentinel node was guided by a probe. After that date, a portable gamma camera was introduced for intrasurgical detection. Results. The SN was biopsied in 725 out of the 754 patients studied. The resulting technique global effectiveness was 96.2%. In accordance with the year of the surgical intervention, the identification percentage was 93.5% in 2003, 88.7% in 2004, 94.3% in 2005, 95.7% in 2006, 93.3% in 2007, 98.8% in 2008, 97.1% in 2009 and 99.1% in 2010 and 2011. There was a significant difference in the proportion of identification before and after the incorporation of the portable gamma camera of 4.6% (95% CI of the difference 2–7.2%, P = 0.0037). Conclusions. The percentage of global identification exceeds the recommended level following the current guidelines. Chronologically, the improvement for this parameter during the study period has been observed. These data suggest that the incorporation of a portable gamma camera had an important role (AU)

Reproducibilidad de la linfogammagrafía antes y después de la biopsia excisional de las lesiones primarias de mama: estudio utilizando la inyección periareolar superficial del radiotrazador / Reproducibility of lymphoscintigraphy before and after excisional biopsy of primary breast lesions: A study using superficial peri-areolar injection of the radiotracer

Objetivo. Una cuestión de gran controversia en la biopsia del ganglio centinela de la mama es la aplicabilidad del estudio del ganglio centinela en pacientes con historia previa de biopsia excisional de las lesiones de la mama. En el presente estudio, evaluamos la reproducibilidad de la linfogammagrafía antes y después de la biopsia excisional de las lesiones primarias de mama utilizando la inyección periareolar superficial del radiotrazador. Material y métodos. Se incluyó en el estudio a 18 pacientes programadas para biopsia excisional de lesiones de mama. A las pacientes se les administró una inyección intradérmica del radiotrazador en el área periareolar del cuadrante con tumor, con 1 o 2h antes de la cirugía. La imagen se obtuvo el día posterior a la operación. Inmediatamente tras la primera imagen, a las pacientes se les administró otra inyección del radiotrazador con la misma técnica, dosis y localización. Se realizaron inmediatamente otras series de imágenes de linfogammagrafía, y a las 4h después de la segunda inyección. Se compararon las 2 series de imágenes de linfogammagrafía. Resultados. En 2 pacientes no se pudo identificar el ganglio centinela en ninguna de las series de imágenes. En las 16 pacientes restantes se detectó un ganglio centinela en ambas series de imágenes de linfogammagrafía. Los ganglios centinela de las segundas series de imágenes se detectaron en la misma localización que las primeras series de imágenes, con un contaje al menos 5 veces superior. Conclusiones. La biopsia excisional de las lesiones primarias de mama no parece modificar el patrón del drenaje linfático superficial desde la areola de la mama, pudiendo realizarse el estudio del ganglio centinela tras esta intervención, utilizando la técnica periareolar superficial(AU)

Objective. A major controversial issue in the sentinel node biopsy of the breast is the applicability of sentinel node mapping in patients with the history of previous excisional biopsy of the breast lesions. In the current study, we evaluated the reproducibility of lymphoscintigraphy before and after excisional biopsy of the primary breast lesions using superficial peri-areolar injection of the radiotracer. Material and methods. Eighteen patients scheduled for excisional biopsy of breast lesions were included into the study. The patients received intra-dermal injection of the radiotracer in the peri-areolar area of the index quadrant 1 to 2h before surgery. Imaging was performed the day after surgery. Immediately after completion of the first imaging, the patients received another injection of the radiotracer with the same technique, dose, and location. Other sets of lymphoscintigraphy imaging were taken immediately and 4h post second injection. The two sets of lymphoscintigraphy images were compared. Results. In 2 patients, sentinel node could not be identified in either set of images. In the remaining 16 patients, one sentinel node was detected in both lymphoscintigraphy image sets. The sentinel nodes of the second image sets were all in the same location of the first sets with at least 5 times higher count. Conclusions. Excisional biopsy of the primary breast lesions does not seem to change the superficial lymphatic drainage pattern from the areola of the breast and sentinel node mapping can be performed after this procedure using superficial periareolar technique(AU)

Implementación de la biopsia selectiva del ganglio centinela en pacientes con cáncer de mama tratadas en hospitales comarcales de la Comunidad Autónoma de Cantabria / Implementation of sentinel lymph node biopsy in patients with breast cancer treated in district hospitals in the autonomous region of Cantabria (Spain)

Objetivo. Evaluar los resultados de la biopsia selectiva del ganglio centinela (GC) en mujeres con cáncer de mama tratadas en hospitales sin servicio de Medicina Nuclear. Sujetos y métodos. El estudio incluyó 88 mujeres con cáncer de mama no avanzado tratadas en 2 hospitales comarcales entre febrero 2007 y julio 2010. El día previo a la cirugía se realizó una linfogammagrafía en el hospital especializado. Para la localización intraoperatoria del GC se utilizaron una sonda radiodetectora y una gammacámara manual. Resultados. El GC se localizó quirúrgicamente en 97,7% de pacientes. La media de ganglios linfáticos extraídos por cada procedimiento y equipo quirúrgico fue 2,1±1,4 y 2,5±1,2. En 27,2% de pacientes se practicó linfadenectomía axilar. Hubo un resultado falso negativo y un falso positivo. Conclusiones. La implementación de la biopsia selectiva del GC en hospitales comarcales proporciona los mismos resultados que los obtenidos en el hospital supervisor (AU)

Objective. To evaluate the results of sentinel lymph node (SLN) biopsy in women with breast cancer treated in hospitals without a nuclear medicine unit. Subjects and methods. Eighty-eight patients with early-stage breast cancer treated in two district hospitals between February 2007 and July 2010 were included. The day before surgery a lymphoscintigraphy was performed in the specialized hospital. Intraoperative localization of the SLN was accomplished by the combined use of a hand-held gamma probe and a manual gamma-camera. Results. Surgical localization of the SLN was successful in 97.7% of the patients. The mean number of lymph nodes excised by each procedure and each surgical team was 2.1±1.4 and 2.5±1.2. Axillary lymph node dissection was performed in 27.2% of the patients. There was one false-negative result and one false-positive result. Conclusion. The implementation of SLN biopsy in district hospitals provides similar results to those obtained in the supervising hospital (AU)

Linfogammagrafía en el diagnóstico diferencial del edema. Rendimiento diagnóstico de diferentes patrones gammagráficos / Lymphoscintigraphy for differential diagnosis of peripheral edema: diagnostic yield of different scintigraphic patterns

El edema de extremidades constituye un motivo frecuente de consulta médica, considerándose la linfogammagrafía un método fiable para su diagnóstico diferencial. Objetivo. Valorar la utilidad del estudio isotópico en el diagnóstico diferencial del edema y el rendimiento diagnóstico de diferentes patrones gammagráficos encontrados. Material y Métodos. Se consideraron 61 pacientes remitidos a nuestro Servicio en los últimos tres años por sospecha de linfedema, descartándose uno por falta de diagnóstico. La media de edad fue de 43 años. Cincuenta y seis pacientes presentaban edema en miembros inferiores y 4 en superiores. Tras inyección intradérmica de dos dosis de 99mTc-nanocoloide, se realizaron rastreos gammagráficos de extremidades a los 30 y 120 minutos de su administración. El diagnóstico definitivo se basó en pruebas de imagen, evolución clínica y respuesta a tratamiento. Se calculó el rendimiento diagnóstico de cuatro diferentes patrones gammagráficos (presencia de flujo dérmico, asimetría-alteración en ganglios inguinales/axilares, presencia de vías colaterales y visualización de ganglios intermedios) considerándose de manera individual y conjunta. Resultados. El mayor rendimiento diagnóstico se alcanzó considerando el flujo dérmico y la asimetría en ganglios inguinales/axilares (exactitud 88,9%, especificidad 96,4%, VPP 95,5%). La valoración de ganglios intermedios y presencia de vías colaterales aportó escaso rendimiento diagnóstico, con baja sensibilidad y elevada tasa de falsos positivos. Conclusión. La linfogammagrafía presentó un alto rendimiento diagnóstico, permitiendo un tratamiento precoz del linfedema. El flujo dérmico y asimetría en ganglios inguinales/axilares mostraron la mayor exactitud diagnóstica. La valoración de ganglios intermedios y visualización de vías colaterales no aportaron mejoría al diagnóstico(AU)

Edema of the limbs is a common reason for medical consultation, for which the lymphoscintigraphy is considered to be a reliable method for its differential diagnosis. Objective. To evaluate the usefulness of radionuclide studies in the differential diagnosis of edema, and the diagnostic yield of different scintigraphic patterns. Material and Methods. A total of 61 patients, mean age 43 years, referred to our Department in the last three years for suspected lymphoedema, were considered. One patient was discarded due to lack of diagnosis, 56 had lower limb edema and 4 upper limb edema. After intradermal injection of two doses of 99mTc-nanocolloid, scintigraphic scans were made at 30 and 120minutes. The final diagnosis was based on imaging tests, clinical course, and response to treatment. We calculated the parameters of the diagnostic yield of four different scintigraphic patterns (presence of dermal backflow, asymmetry-alteration in inguinal/axillary nodes, presence of collateral pathways, and visualization of intermediate lymph nodes), considering them individually and jointly. Results. The best diagnostic yield was achieved by considering dermal backflow and asymmetry in inguinal/axillary nodes (accuracy 88.9%, specificity 96.4%, PPV 95.5%). Evaluation of intermediate lymph nodes and presence of collateral pathways contributed little to the diagnostic yield, showing poor sensitivity and high false positive rates. Conclusion. The lymphoscintigraphy had high diagnostic yield, allowing early treatment of lymphœdema. The dermal backflow and asymmetry in inguinal/axillary nodes had the greatest diagnostic accuracy. Evaluation of intermediate lymph nodes and visualization of collateral pathways contributed little to improving the diagnosis(AU)

A quantitative examination of lymph drainage from perilesion skin in human melanoma.

BACKGROUND: An increase in lymph flow from melanomas to draining lymph nodes has been reported in animal studies. It has been postulated that this contributes to metastatic potential of cancers. Data from animal studies are not easily extrapolated to humans; animal studies use immunosuppressed animals modified to overexpress lymphangiogenic growth factors, injected with human tumor cell lines, or manipulated to develop aggressive tumors. Human studies are required to investigate lymph flow in humans with cancers such as melanoma. METHODS AND RESULTS: The present study aims to quantify the removal rate constant k (a measure of local lymph flow per unit volume of distribution of the radiotracer) from the vicinity of melanomas, benign nevi, and normal skin in humans in vivo using quantitative lymphoscintigraphy (QL). 16 patients with pigmented lesions underwent QL to quantify k near the lesion (k(perilesion)) and in contralateral matched normal skin (k(control)). The lesions were then excised and, based on histological outcome, the patients were divided into two groups: benign nevus (n=9) and melanoma (n=7). There was no difference between k(perilesion) and k(control) in either the benign naevus (p=0.29, paired t test) or the melanoma group (p=0.93). k(perilesion) in melanomas (0.233±0.123% min(-1)) was not increased relative to k(perilesion) in benign nevi (0.376±0.231% min(-1), p=0.16, unpaired t test). CONCLUSIONS: We found no evidence for increased lymphatic drainage in melanoma relative to benign nevi or normal matched skin in humans.

Drenaje linfático del cáncer de próstata a través de la linfogammagrafía y el SPECT/TAC: su importancia en la técnica del ganglio centinela / Lymphatic drainage in prostate carcinoma assessed by lymphoscintigraphy and SPECT/CT: its importance for the sentinel node procedure

Objetivo. Valorar la técnica del ganglio centinela en relación con los diferentes patrones de drenaje linfático y con las áreas de linfadenectomía pélvica en pacientes con cáncer de próstata a través de la linfogammagrafía y el SPECT/TAC. Método. Se inyectó un total de 240 MBq de 99mTc-nanocoloide divididos en 4 dosis (una para cada cuadarante) mediante control ecográfico transrectal en 18 pacientes con cáncer de próstata con estadio superior a T2b. La inyección también fue controlada con una gammacámara portátil para asegurar que no se producía difusión del trazador fuera de la próstata. Tras la inyección, se realizaron imágenes planares a los 15min y 2h, junto a un SPECT-TAC a las 2h con cortes de 2mm. El mismo día, se realizó la técnica del ganglio centinela vía laparoscopia guiado por una sonda gamma y una gammacámara portátil. Resultados. Un total de 55 ganglios centinelas (GC) fueron visualizados. En 17/18 de los pacientes (94%) se observaron GC fuera de la fosa obturatriz. Se apreciaron 20 GC a lo largo de la arteria ilíaca externa (36%), 14 en la fosa obturatriz (25,4%), 6 en área de la ilíaca interna (11%) y 4 en la ilíaca común (7,2%). Se localizaron también 3 GC en la región presacra (5,4%), paraórtica (5,4%), y pararrectal (5,4%) y 2 a en región paravesical (3,6%). Se observaron metástasis en el GC en 6 pacientes (33%) y, en uno de ellos, un GC localizado alrededor de la artería ilíaca común fue el único con metástasis. Conclusión. El drenaje linfático de la próstata presenta una gran variabilidad individual, y con frecuencia se observan drenajes fuera del área pélvica. Con la técnica del GC, los GC situados fuera del área de rutina de la linfadenectomía pélvica pueden ser extirpados, estadificándose con mayor precisión al paciente(AU)

Purpose. The goal was to evaluate the sentinel node procedure in relation to different pathways of lymphatic drainage and the areas of pelvic lymphadenectomy in patients with prostate cancer assessed by lymphoscintigraphy and SPECT/CT study. Methods. Eighteen patients with prostate cancer of intermediate prognosis were injected with 240 MBq of 99mTc-nanocolloid in the peripheral zone of each quadrant of the prostate, guided by transrectal ultrasonography. Tracer administration was also controlled with a portable gamma camera to assure that there was no diffusion outside the prostate. The injection was followed by planar imaging at 15min. and 2h, performing a SPECT/CT study at 2h. with 2mm slices. On the same day, a laparoscopic sentinel node lymphadenectomy assisted by a gamma probe and a portable gamma camera was performed. Results. A total of 55 sentinel lymph nodes (SLNs) were visualized. In 17/18 of patients (94%) SLNs were observed outside the obturator region. Twenty SLNs (36%) were observed along the external iliac artery, 14 in the obturator fossa (25.4%), 6 in internal iliac area (11%) and 4 in common iliac region (7.2%). Three SLNs were visualized in presacral (5.4%), paraaortic (5.4%), and pararectal areas (5.4%) and two in paravesical region (3.6%). SLN metastases were found in 6 patients (33%), and in one of them, a SLN located along the common iliac artery, was the only one with metastases. Conclusion. Lymphatic drainage from the prostate has high individual variability, and direct drainage outside the pelvic area is observed frequently. With the SLN procedure, SLNs outside the routine area of lymphadenectomy can also be sampled to stage the patient more accurately(AU)

Evaluation of patient effective dose from sentinel lymph node lymphoscintigraphy in breast cancer: a phantom study with SPECT/CT and ICRP-103 recommendations.

OBJECTIVE: To evaluate the effective dose delivered to patients undergoing sentinel lymph node (SLN) lymphoscintigraphy by taking into account both the transmission dose using the CT component of a SPECT/CT system and the (99m)Tc internal emission dose. MATERIALS AND METHODS: An adult female humanoid phantom and a set of thermoluminescent dosimeters were used in dose measurement from the CT transmission irradiation. The choice of measurement organs in the humanoid was guided by the recommendations described in the International Commission on Radiological Protection report number 103 (ICRP-103). The effective doses due to (99m)Tc internal emission source were re-calculated from measurement data reported in our previous study on the same subject with the use of tissue weighting factors of ICRP-103. RESULTS: CT transmission dose is the main contribution to the patient total effective dose for both 1-day and 2-day lymphoscintigraphy protocols and for different surgical procedures. Patients undergoing SLN lymphoscintigraphy receive about the same amount of total effective dose of about 3mSv for both 1-day and 2-day protocol, regardless of whether the tissues containing radioactivity would be excised at surgery or not. CONCLUSION: Although the total effective dose from using SPECT/CT is equivalent to the annual natural background radiation of about 3mSv, nuclear medicine physicians should be aware of the increase in effective dose for SLN lymphoscintigraphy using hybrid imaging technique of SPECT/CT when compared to conventional planar (57)Co flood source for transmission scan. Results from the current study provide update information in radiation exposure to patients undergoing SLN lymphoscintigraphy with the use of SPECT/CT.

Thoracic lymphangiomatosis with massive chylothorax after a tumor biopsy and with disseminated intravenous coagulation--lymphoscintigraphy, an alternative minimally invasive imaging technique: report of a case.

Thoracic lymphangiomatosis in childhood is a rare disorder that frequently has poor response to medical therapy as well as a poor prognosis. This disease is often misdiagnosed, and a definitive diagnosis is usually delayed because of the rarity and slow course of the disease. No previous reports have so far described the usefulness of lymphoscintigraphy in the diagnosis of lymphangiomatosis, although some authors have reported the efficacy of lymphoscintigraphy for evaluating chylothorax. A 6-year-old boy presented with a diffuse mediastinal mass and received an open mediastinal biopsy for a definitive diagnosis, which led to the occurrence of massive chylothorax postoperatively. A diagnosis of lymphangiomatosis was finally made based on the lymphoscintigraphic findings demonstrating an obstruction of the thoracic duct. This report describes a rare case of thoracic lymphangiomatosis diagnosed at autopsy, and suggests that the minimally invasive technique of lymphoscintigraphy should be employed to obtain a definitive diagnosis at an early stage.