Concordance between preoperative imaging methods in patients with limb lymphedema undergoing supermicrosurgical lymphaticovenular anastomosis.

OBJECTIVE: Supermicrosurgical lymphaticovenular anastomosis (LVA) is increasingly being recognized as a first-line treatment for limb lymphedema because it is minimally invasive and highly effective. Lymphoscintigraphy and indocyanine green (ICG) lymphography are the two most commonly performed diagnostic imaging examinations to establish the indication and plan the procedure in patients affected by limb lymphedema. In a small group of patients, the information between these two imaging tools can be discordant, showing different anatomical drainage pathways or showing absence of drainage and dermal backflow in one examination, and valid drainage pathways in the other. The purpose of this study is to examine the types of possible discrepancies between lymphoscintigraphy of the superficial system and ICG lymphography, and to describe the surgical outcome after LVA in patients presenting such discrepancies. METHODS: We retrospectively reviewed the data of all patients who underwent LVA for upper or lower limb lymphedema between July 2015 and July 2023. From this series, we identified a group of patients who had non-concordant imaging results from lymphoscintigraphy and ICG-L prior to lymphatic surgery. Non-concordant findings were described in terms of "pattern discordance" or "pathway discordance". Surgical outcome was measured by the change in mean circumference of the limb after surgery. The changes between preoperative and postoperative limbs' measures were analyzed by Student's t-test. P values<0.05 were considered significant. RESULTS: A total of 28 patients with limb lymphedema exhibited inconsistencies between preoperative lymphoscintigraphy of the superficial system and ICG lymphography. Among these patients, 14 experienced "pattern discordance", while 13 had "pathway discordance", and 1 patient had both. After LVA, we observed a significant reduction in the average circumference of the affected limb in the analyzed group. CONCLUSIONS: The discrepancy of information between lymphoscintigraphy and ICG lymphography in the preoperative study of patients affected by limb lymphedema is rare but possible. This phenomenon is still not fully explained, but our results suggest that it does not correlate with the outcome of supermicrosurgical lymphovenous anastomoses.

Rest/Stress Intradermal Lymphoscintigraphy for the Functional Imaging of the Lymphatic System.

PURPOSE: Lymphoscintigraphy is the criterion-standard method for diagnosing lymphedema, and there is no universally standardized imaging modality. In our center, we use a new approach: rest/stress intradermal lymphoscintigraphy. METHODS: We tested 231 consecutive patients with suspected lymphedema. All patients were studied after a complex physical therapy program to reduce edema. Two doses of 99m Tc-nanocolloid were injected intradermally. Two static planar scans were taken at rest following tracer injection. Next, patients performed an isotonic muscular exercise for 2 minutes followed by postexercise scans. Subsequently, a prolonged exercise was performed for 30 to 40 minutes, after which delayed scans were taken. Abnormal patterns were distinguished into minor or major findings, according to severity. RESULTS: We identified superficial lymphatic vessels and regional lymph nodes in approximately 80% of limbs. Deep vessels were visualized in 26% of limbs. Minor findings were reported in 22.7% of limbs examined, whereas major findings were reported in 53.2% of limbs. CONCLUSION: We observed major findings including lymph stagnation, extravasation, or dermal backflow in a significantly higher percentage of limbs with secondary lymphedema than in primary. We also observed the deep lymphatic pathways in a significantly higher percentage of limbs with primary lymphedema. Intradermal radiotracer injection, combined with isotonic muscular exercise, may offer a better and faster imaging of lymphatic pathways, evaluating the effects of muscular exercise on lymphatic drainage. Based on the in-depth information of the lymphatic pathways provided by rest/stress intradermal lymphoscintigraphy, microsurgeons can obtain important functional information to perform supermicrosurgical lymphatic-venous anastomosis or vascularized lymph node transfer.

Lymphaticovenular Anastomosis for Advanced-Stage Peripheral Lymphedema: Expanding Indication and Introducing the Hand/Foot Sign.

BACKGROUND: Effective lymphaticovenular anastomosis (LVA) requires identification of functioning lymphatics, which are not always visible with contrast-based imaging in advanced-stage lymphedema patients. Ultrasound (US) allows to identify preoperatively functioning lymphatic vessels even in limbs severely affected by lymphedema. Moreover, in our experience, we observed an interesting clinical sentry in advanced-stage lymphedema patients, the hand/foot sign that is analyzed in this paper. PATIENTS AND METHODS: From January 2016 to January 2019, 76 consecutive advanced-stage secondary lymphedema patients underwent LVA. Preoperative planning included lymphoscintigraphy, indocyanine-green lymphography (ICG-L) and US. Patients' features, the hand/foot sign (preservation of more normal skin on the dorsum of the hand or foot), lymphatic degeneration, quantitative, qualitative, and composite outcomes at 1-year follow-up were evaluated. RESULTS: An average number of 3±0.1 LVA was performed in upper limb lymphedema (ULL) (range 2-5, 47 patients) and of 4±1.08 LVAs in lower limb lymphedema (LLL) cases (range 4-7, 29 patients). The composite outcome was positive in 45 cases (59.7%). The "negative" hand /foot sign was significantly associated with presence of functioning lymphatic channels. The incidence of adverse outcomes was significantly higher in patients with positive hand/foot sign. CONCLUSION: Patients with no functioning lymphatic vessels detectable by lymphoscintigraphy and ICG-L may still have functioning lymphatic channels that can be identified preoperatively by ultra-high-frequency ultrasound and salvaged by LVA. The "hand/foot sign" is a simple clinical sentry that appears to be correlated with higher probability of being able to localize functional lymphatics for potential lymphovenous bypass surgery.

A gravity-assisted approach to the management of urinary diversion: 99mTc-MAG3 diuresis renography with F + 10(sp) method.

OBJECTIVE: Radical cystectomy with permanent urinary diversion is the gold standard treatment for invasive muscle bladder cancer. Hydronephrosis is common in these patients, but Ultrasound (US) or Computed Tomography Urography (CTU) scan are unable to discriminate obstructive from non-obstructive hydronephrosis. We used Diuresis Renography (DR) with F + 10 in seated position (sp) method in the identification of patients with a Uretero-ileal Anastomosis Stricture (UAS) who would benefit from surgical therapy. METHODS: We studied 39 asymptomatic patients, who underwent radical cystectomy and urinary diversion. Based on radiological findings (US, CTU) 44 kidneys were hydronephrotic. All patients underwent a 99mTc-MAG3 DR with F + 10(sp) method. We acquired a DR for 20 min with the patient in a seated position. Patient drank 400-500 mL of water at 5 min after tracer injection and received a 20 mg bolus of Furosemide at 10 min during dynamic acquisition. The indices Time to peak, diuretic half time, and 20 min/peak ratio have been evaluated. Retrograde pyelography confirmed UAS in all patients with DR obstructive findings. We repeated DR as follow-up in two subgroups of patients. RESULTS: DR with F + 10(sp) method showed obstructive findings in 36 out of 44 hydronephrotic kidneys. 6 patients showed non-obstructive findings. 32 patients showed obstructive findings (20 out of 32 developed UAS within 12 months after surgery). Fifteen pts underwent a surgical treatment of UAS. In 1 patient with equivocal findings, we observed an ileo-ureteral reflux. CONCLUSIONS: The DR with F + 10(sp) method in the seated position has a lower uncertain diagnostic rate, compared to the radiological findings of US or CTU, in management of bladder cancer patients with urinary diversion. The semiquantitative indices diuretic half time and 20 min/peak ratio evaluated in a condition of favorable gravity reduce uncertain responses improving interobserver concordance.

Radioguided sentinel node biopsy to avoid unnecessary neck dissection in T1-T2N0 oral cavity squamous cell carcinoma: personal experience with same day protocol.

PURPOSE: Data from literature show a mean incidence of occult metastases of 33% in early OCSCC. The gold standard for most authors is a selective neck dissection and a routine pathological examination. 60-70% of unnecessary neck dissections with associated morbidity, can be avoided by using SNB. The aim of this study is to present the results of one of the major Italian centres for the SNB procedure, reserving neck dissection only for proven positive lymphatic metastases. METHODS: From July 2004 to March 2015, 48 patients with transorally resectable cT1-T2N0 oral SCC were submitted to a lymphoscintigraphic examination one-three hours before surgery and a radio-guided SNB (same day protocol). Patients with a negative SNB were checked every 3 months by ultrasound examination. The minimum follow-up was 5 years. RESULTS: Sentinel nodes were found in all cases, with 71% localized in the ipsilateral neck only in levels I-II. Metastases were found in 15 out of 48 cases (31.2%), on levels I, II and III. Further metastatic nodes were found in 6 cases in the neck dissection specimen. In the cohort of 33 patients with SNB negative at 5 years, no-one had a recurrence on the ipsilateral neck. CONCLUSION: This study confirms the accuracy of SNB in predicting the presence of occult metastases, sparing the need for unnecessary neck dissection in 70% of cases. The same day protocol is designed to detect sentinel nodes, which are almost always on neck level I-II, thereby limiting the number of nodes examined and the extension of the surgical approach.

Rest/stress intradermal lymphoscintigraphy in diagnosis of lipedema.

Lipedema is a chronic and progressive disease characterized by a symmetrical and bilateral swelling of the lower extremities. In general, the feet are not involved. Lipedema is believed to affect nearly 1 in 9 adult women worldwide. Despite this relatively common disease, lipedema is often confused with primary lymphedema or obesity. In clinically advanced lipedema stages, fat continues to build up and may block the lymphatic vessels causing a secondary lymphedema (Lipo-Lymphedema). We consecutively evaluated 54 women with a clinical diagnosis of lower limbs lipedema. Two doses of 99mTc-nanocolloid were injected intradermally at the first intermetatarsal space and in the lateral malleolar area. Two static planar scans were taken at rest immediately following the intradermal injection. Subsequently, all patients were asked to perform an isotonic muscular exercise (stepping) for 2 min. Then, post exercise scans were performed to monitor the tracer pathway. Subsequently, the patient was asked to take a 30-40 min walk (prolonged exercise) and delayed scans were acquired. In early clinical stages, the lymphatic flow is usually preserved and the rest/stress intradermal lymphoscintigraphy may visualize a normal lymphatic drainage with a frequent pattern (tortuous course) of the leg lymphatic pathway. In clinically advanced stages, lymph stagnation areas were observed. Unlike obesity, lipedema fat storage is resistant to dietary regimen, bariatric surgery, and physical activity. Surgical treatment (tumescent liposuction and reductive surgery) is the most effective treatment to remove adipose tissue. Complex decongestive therapies are helpful in reducing the lymph stagnation, especially in patients with advanced lipolymphedema.

Intradermal-Stress-Lymphoscintigraphy in Early Detection and Clinical Management of Secondary Lymphedema: A Pictorial Essay.

Stress-lymphoscintigraphy evaluates the effects of exercise on lymph drainage. Results may predict outcomes of complex physical therapy as a first-line lymphedema treatment. Microsurgical approaches are best in patients with lymphangectasia or dermal backflow. Lymphatic pathway mapping helps plan lympho-venous anastomoses. For improved lymphatic visualization, we suggest a scan at rest, after a quick exercise (stepping or weight lifting for 2 min) and delayed scanning after prolonged symptom limited exercise (walking or hand squeezing for 30-40 min). In advanced lymphedema, identification of lymph pathways and residual regional lymph nodes might be difficult. In these patients, lymph node transplant is suggested.

Lymphoscintigraphy for the evaluation of limb lymphatic flow disorders: Report of technical procedural standards from an Italian Nuclear Medicine expert panel. / Linfogammagrafía para la evaluación de trastornos del flujo linfático de las extremidades: informe de estándares de procedimientos técnicos de un panel de expertos de medicina nuclear italiano.

Lymphoscintigraphy represents the "gold standard" for diagnosis of lymphedema, but an important limitation is the lack of procedural standardization. The aim of this Italian expert panel was to provide a procedural standard for lymphoscintigraphy in the evaluation of lymphatic system disorders. Topic anaesthetic gels containing lidocaine should be avoided. Patients should remove compressive dressings. Total recommended activity for 99mTc-nanocolloid administration in adults is 74MBq, or 37MBq per limb and per investigated compartment, in single or multiple aliquots. 2-3 subcutaneous injections should be performed (II-III±I interdigital space of each hand/foot), avoiding intravascular injection. Deep lymphatic system of lower limbs should be evaluated in presence of dermal back-flow or lymphatic stasis (1-2 subfascial administrations in retro-malleolar or plantar region). Planar images should be acquired from injection site to liver with whole-body or serial static acquisitions 20' and 90' after subcutaneous administration. Additional information on lymphatic pathways is obtained after a quick and/or prolonged exercise protocol. SPECT/CT is recommended to study the thoracic, abdominal and pelvic territories. When required, deep lymphatic system of lower limbs should be evaluated with static acquisition 90' after subfascial administration. The report should describe administration and imaging procedure, exercise protocol, qualitative and semi-quantitative analysis (wash-out rate, transport index), potential sources of error. Due to the essential role fulfilled by lymphoscintigraphy in clinical management of primary and secondary lymphedema, an effort for the standardization of this technique should be made to provide the clinicians with a homogeneous and reliable technical methodology.

Compartimental harvesting of dual lymph node flap from the right supraclavicular area for the treatment of lower extremity lymphedema: A case series.

BACKGROUND: We report our clinical experience of a supraclavicular lymph node flap (LNF) using a novel method of harvesting based on the compartimental lymphatic and vascular anatomy of the right posterior neck triangle, which allows to harvest two independent LNFs from the same donor site. PATIENTS AND METHODS: We report a case series of 10 consecutive patients affected by cancer-related lower extremity lymphedema, who underwent compartimental dual LNF transfer from the right supraclavicular area to the affected lower limb, from August 2015 to March 2017. The superficial compartment flap (venous flap along the external jugular vein) was anastomosed in a flow-through fashion along the course of the great saphenous vein in the knee region, whereas the deep compartment flap (transverse cervical artery/vein flap) was anastomosed in an end-to-end fashion to the medial sural artery and comitantes vein. Flap viability was checked by color Doppler ultrasound postoperatively. Patients were assessed preoperatively and underwent follow-up at 6 and 12 months after surgery. Data were prospectively collected. RESULTS: All the flaps resulted to be viable. No major postoperative complications were observed neither at the donor nor at the recipient sites. Patients did not report dysesthesia of the homoteral chest. An overall reduction in the lower extremity lymphedema (LEL) index (mean ±â€¯SD: 33.7 ±â€¯22.5) and an improvement in the lymph flow and tracer appearance time at postoperative lymphoscintigraphy were observed. All the patients reported an improved quality of life after surgery. CONCLUSIONS: Compartimental supraclavicular dual LNF harvest seems promising in the treatment of peripheral lymphedema. Sparing of supraclavicular nerves might reduce the morbidity associated with the conventional surgical approach. Larger studies are needed to confirm our findings. LEVEL OF EVIDENCE: IV, therapeutic study.

The EANM practical guidelines for sentinel lymph node localisation in oral cavity squamous cell carcinoma.

PURPOSE: Sentinel lymph node biopsy is an essential staging tool in patients with clinically localized oral cavity squamous cell carcinoma. The harvesting of a sentinel lymph node entails a sequence of procedures with participation of specialists in nuclear medicine, radiology, surgery, and pathology. The aim of this document is to provide guidelines for nuclear medicine physicians performing lymphoscintigraphy for sentinel lymph node detection in patients with early N0 oral cavity squamous cell carcinoma. METHODS: These practice guidelines were written and have been approved by the European Association of Nuclear Medicine (EANM) and the International Atomic Energy Agency (IAEA) to promote high-quality lymphoscintigraphy. The final result has been discussed by distinguished experts from the EANM Oncology Committee, and national nuclear medicine societies. The document has been endorsed by the Society of Nuclear Medicine and Molecular Imaging (SNMMI). These guidelines, together with another two focused on Surgery and Pathology (and published in specialised journals), are part of the synergistic efforts developed in preparation for the "2018 Sentinel Node Biopsy in Head and Neck Consensus Conference". CONCLUSION: The present practice guidelines will help nuclear medicine practitioners play their essential role in providing high-quality lymphatic mapping for the care of early N0 oral cavity squamous cell carcinoma patients.

Stress Lymphoscintigraphy for Early Detection and Management of Secondary Limb Lymphedema.

Cancer treatments with axillary or pelvic lymph nodes dissection and radiation place patients at lifelong risk for the development of secondary lymphedema. Our aim was to evaluate the role of stress lymphoscintigraphy for early detection and management of secondary lymphedema. METHODS: Stress lymphoscintigraphy was performed within 1 year after surgery and the completion of chemotherapy and radiation treatments. All patients were classified by the International Society of Lymphology clinical stages from 0 to 3. A dose of 50 MBq of 99mTc-HSA-nanocolloidal in 0.4mL was injected intradermally at the first and fourth intermetacarpal spaces on the hand, for the upper limb with edema, or at the first intermetatarsal space and at the lateral malleolus for lower extremities. Two planar static scans at rest were acquired immediately after tracer injection. Stress scans were acquired after weight lifting for upper extremity or stepping for 2 minutes for lower-extremity edema. After that, the patients underwent prolonged muscular exercise limited by symptoms, and later scans were acquired at 60 minutes to visualize regional lymph nodes and the effects of sustained muscular exercise. Transport Index was evaluated. RESULTS: Five patterns of lymphoscintigraphy were observed. In our experience, patients with types I to III pattern benefit from an exercise program as a first-line treatment. Patterns IVand V seem to be predictive of lymphedema. CONCLUSIONS: The abnormal patterns found may provide the basis for earlier complex physical therapy or microsurgical treatment of lymphatic disorders in patients resulting in improved outcomes.

Lymphatic mapping of the upper limb with lymphedema before lymphatic supermicrosurgery by mirroring of the healthy limb.

INTRODUCTION: Supermicrosurgical lymphatic-venous anastomosis (LVA) can improve limbs lymphedema. We describe a technique that we employ for preoperative lymphatic mapping of the upper limb (UL), when indocyanine green (ICG) lymphography shows only dermal backflow (DB) and no lymphatic vessel is detectable. PATIENTS AND METHODS: Sixteen patients undergoing LVA for unilateral UL lymphedema, showing "stardust" or "diffuse" DB pattern, were included. Demographic, clinical data, and limbs measurements were recorded. LymQoL arm questionnaire was administered. Mean age of patients was 58.8 ± 13.1 years. Fifteen were females and 1 male. Lymphatic anatomy of the healthy limb was investigated by ICG lymphography and reported on the affected limb by a four steps technique: marking the main lymphatic pathway on the healthy limb, measuring of the distances at seven levels between the pathway and a line joining fixed landmarks, reporting these measurements on the affected limb with a correction proportional to the degree of swelling, marking skin incisions at the intersection of this pathway with venules, individuated by near infrared light system. Results were analyzed by postoperative questionnaire and changes of limb measurements. RESULTS: For every limb, we could find 3 ± 0.73 incision sites each containing at least one lymphatic vessel suitable for anastomosis. In every patient, we could perform 3.38 ± 0.62 anastomoses. Mean follow-up was 12.13 ± 2.73 months. After surgery, mean preoperative QoL score increased from 5.5 to 7.9 (P < .001), and mean difference between the mean circumferences of the affected and healthy limbs decreased from 4.3 ± 1.3 to 2.5 ± 1.3 cm, showing improvement of swelling after surgery (P < .01). CONCLUSION: This technique allowed to preoperatively map UL lymphatics even if diffuse DB was present.

The Progressive Advances of Sentinel Lymph Node Biopsy Technique in Head and Neck Cancer.

In this short review, the technical and clinical improvements of the sentinel lymph node biopsy in head and neck cancer are presented.

Sentinel Node in Oral Cancer: The Nuclear Medicine Aspects. A Survey from the Sentinel European Node Trial.

PURPOSE: Nuclear imaging plays a crucial role in lymphatic mapping of oral cancer. This evaluation represents a subanalysis of the original multicenter SENT trial data set, involving 434 patients with T1-T2, N0, and M0 oral squamous cell carcinoma. The impact of acquisition techniques, tracer injection timing relative to surgery, and causes of false-negative rate were assessed. METHODS: Three to 24 hours before surgery, all patients received a dose of Tc-nanocolloid (10-175 MBq), followed by lymphoscintigraphy. According to institutional protocols, all patients underwent preoperative dynamic/static scan and/or SPECT/CT. RESULTS: Lymphoscintigraphy identified 723 lymphatic basins. 1398 sentinel lymph nodes (SNs) were biopsied (3.2 SN per patient; range, 1-10). Dynamic scan allowed the differentiation of sentinel nodes from second tier lymph nodes. SPECT/CT allowed more accurate anatomical localization and estimated SN depth more efficiently. After pathological examination, 9.9% of the SN excised (138 of 1398 SNs) showed metastases. The first neck level (NL) containing SN+ was NL I in 28.6%, NL IIa in 44.8%, NL IIb in 2.8%, NL III in 17.1%, and NL IV in 6.7% of positive patients. Approximately 96% of positive SNs were localized in the first and second lymphatic basin visualized using lymphoscintigraphy. After neck dissection, the SN+ was the only lymph node containing metastasis in approximately 80% of patients. CONCLUSIONS: Best results were observed using a dynamic scan in combination with SPECT/CT. A shorter interval between tracer injection, imaging, and surgery resulted in a lower false-negative rate. At least 2 NLs have to be harvested, as this may increase the detection of lymphatic metastases.

Sentinel European Node Trial (SENT): 3-year results of sentinel node biopsy in oral cancer.

PURPOSE: Optimum management of the N0 neck is unresolved in oral cancer. Sentinel node biopsy (SNB) can reliably detect microscopic lymph node metastasis. The object of this study was to establish whether the technique was both reliable in staging the N0 neck and a safe oncological procedure in patients with early-stage oral squamous cell carcinoma. METHODS: An European Organisation for Research and Treatment of Cancer-approved prospective, observational study commenced in 2005. Fourteen European centres recruited 415 patients with radiologically staged T1-T2N0 squamous cell carcinoma. SNB was undertaken with an average of 3.2 nodes removed per patient. Patients were excluded if the sentinel node (SN) could not be identified. A positive SN led to a neck dissection within 3 weeks. Analysis was performed at 3-year follow-up. RESULTS: An SN was found in 99.5% of cases. Positive SNs were found in 23% (94 in 415). A false-negative result occurred in 14% (15 in 109) of patients, of whom eight were subsequently rescued by salvage therapy. Recurrence after a positive SNB and subsequent neck dissection occurred in 22 patients, of which 16 (73%) were in the neck and just six patients were rescued. Only minor complications (3%) were reported following SNB. Disease-specific survival was 94%. The sensitivity of SNB was 86% and the negative predictive value 95%. CONCLUSION: These data show that SNB is a reliable and safe oncological technique for staging the clinically N0 neck in patients with T1 and T2 oral cancer. EORTC Protocol 24021: Sentinel Node Biopsy in the Management of Oral and Oropharyngeal Squamous Cell Carcinoma.

The evolving methodology to perform limb lymphoscintigraphy: from rest to exercise acquisition protocol.

In this technical report, prepared following the kind invitation of Professor D'Amore, we describe the evolution in the methodology of performing the limb lymphoscintigraphy. In details we described and compared the rest protocol with subcutaneous injection of the radio-colloids vs. the exercise intradermal injection protocol. The latter appears to be faster and easier to interpret, moreover allowing an adequate measurements of quantitative parameters of lymph drainage and distribution.

Intradermal lymphoscintigraphy at rest and after exercise: a new technique for the functional assessment of the lymphatic system in patients with lymphoedema.

AIM: The aim of this study was to evaluate the effect of implementing a new technique, intradermal injection lymphoscintigraphy, at rest and after muscular exercise on the functional assessment of the lymphatic system in a group of patients with delayed or absent lymph drainage. METHODS: We selected 44 patients (32 women and 12 men; 15 of 44 with upper limb and 29 of 44 with lower limb lymphoedema). Thirty of 44 patients had bilateral limb lymphoedema and 14 of 44 had unilateral disease; 14 contralateral normal limbs were used as controls. Twenty-three patients had secondary lymphoedema after lymphadenectomy and the remaining 21 had idiopathic lymphoedema. Each of the 44 patients was injected with 50 MBq (0.3-0.4 ml) of (99m)Tc-albumin-nanocolloid, which was administered intradermally at the first interdigital space of the affected limb. Two planar static scans were performed using a low-energy general-purpose collimator (acquisition matrix 128 x 128, anterior and posterior views for 5 min), and in which drainage was slow or absent, patients were asked to walk or exercise for 2 min. A postexercise scan was then performed to monitor and record the tracer pathway and the tracer appearance time (TAT) in the inguinal or axillary lymph nodes. RESULTS: The postexercise scans showed that (i) 21 limbs (15 lower and six upper limbs) had accelerated tracer drainage and tracer uptake in the inguinal and/or axillary lymph nodes. Two-thirds of these showed lymph stagnation points; (ii) 27 limbs had collateral lymph drainage pathways; (iii) in 11 limbs, there was lymph drainage into the deeper lymphatic channels, with unusual uptake in the popliteal or antecubital lymph nodes; (iv) six limbs had dermal backflow; (v) three limbs did not show lymph drainage (TAT=not applicable). TAT=15 + or - 3 min, ranging from 12 to 32 min in limbs with lymphoedema versus 5 + or - 2 min, ranging from 1 to 12 min in the contralateral normal limbs (P<0.001). CONCLUSION: Intradermal injection lymphoscintigraphy gives a better imaging of the lymph drainage pathways in a shorter time, including cases with advanced lymphoedema. In some patients with lymphoedema, a 2-min exercise can accelerate tracer drainage, showing several compensatory mechanisms of lymph drainage. The effect of the exercise technique on TAT and lymphoscintigraphy findings could result in a more accurate functional assessment of lymphoedema patients.

The impact of superficial injections of radiocolloids and dynamic lymphoscintigraphy on sentinel node identification in oral cavity cancer: a same-day protocol.

AIM: To evaluate the role of dynamic lymphoscintigraphy with a same-day protocol for sentinel node biopsy in oral cavity cancer. METHODS: Twenty-two consecutive patients affected by cT1-2N0 squamous cell carcinoma of the oral cavity were enrolled between September 2001 and November 2005. After a local anaesthetic (10% lidocaine spray), a dose of 30-50 MBq of Tc human serum albumin nanocolloid, in ml saline, was injected superficially (1-2 mm subendothelial injection) into four points around the lesion. Dynamic lymphoscintigraphy was acquired immediately (256x256 matrix, 5 min pre-set time, LEGP collimator) in lateral and anterior projections. The imaging was prolonged until the lymph nodes of at least two neck levels were visualized (time required min). About 3 h later (same-day protocol) the patients had a radioguided sentinel node biopsy. Elective neck dissection was performed in the first 13 patients; whereas the last nine patients had elective neck dissection only if the sentinel node was positive. Sentinel nodes were dissected into 1 mm thick block sections and studied by haematoxylin & eosin staining and immunohistochemistry (anticytokeratin antibody). RESULTS: The sentinel nodes were found on the 1st neck level in 13 cases, on the 2nd neck level in eight cases, and on the 3rd neck level in one case (100% sensitivity). The average number of sentinel nodes was 2.2 for each patient. The sentinel node was positive in eight patients (36%); with six of them having the sentinel node as the exclusive site of metastasis. No skip metastases were found in the 14 patients with negative sentinel node (100% specificity). CONCLUSION: Our preliminary data indicate that superficial injections of radiocolloid and dynamic lymphoscintigraphy provide a high success rate in sentinel node identification in oral cavity cancers. Dynamic lymphoscintigraphy helps in distinguishing sentinel node from second-tier lymph nodes. The same-day protocol is advisable in order to correctly identify the first sentinel node, avoiding multiple and unnecessary node biopsies, without reducing sensitivity.