Dynamic sentinel node biopsy for penile cancer: reliability of a staging technique

PURPOSE: We determine the value of dynamic sentinel node biopsy for staging squamous cell carcinoma of the penis. MATERIALS AND METHODS: A total of 90 patients with clinically node negative penile cancer were prospectively entered in this study. Preoperative lymphoscintigraphy was performed after intradermal injection of 99mtechnetium nanocolloid around the primary tumor. The sentinel node was intraoperatively identified with the aid of intradermal administered patent blue dye and a gamma ray detection probe. Histopathological examination of sentinel nodes included serial sectioning and immunohistochemical staining. Regional lymph node dissection was performed only if metastasis was found in a sentinel node. Median followup was 36 months (range 5 to 95). RESULTS: Lymphoscintigraphy visualized 217 sentinel nodes in 159 inguinal regions of 88 patients. A total of 208 sentinel nodes were intraoperatively identified in 149 inguinal regions of 88 patients. Sentinel node metastasis was found in 19 inguinal regions of 18 patients. Four of 8 patients with unilateral clinical stage N1 disease had a tumor positive sentinel node on the opposite site. Regional recurrence after excision of a tumor negative sentinel node or after nonvisualization was seen in 5 patients, resulting in a false-negative rate of 22% (5 of 23). The 3-year disease specific survival was 98% and 71% for patients with a tumor negative or tumor positive sentinel node, respectively (p = 0.0018). CONCLUSIONS: Occult lymph node metastases in penile cancer can be detected with a sensitivity of about 80% by dynamic sentinel node biopsy, including preoperative lymphoscintigraphy, vital dye and a gamma ray detection probe.     

Lymphoscintigraphy in penile cancer: limited value of sentinel node biopsy in patients with clinically suspicious lymph nodes

The staging lymph node dissection in patients with penile carcinoma is accompanied with a high morbidity. As many patients are free of nodal metastases the lymphoscintigraphic sentinel node biopsy is supposed to minimize perioperative morbidity in these patients. In the current study the accuracy of the lymphoscintigraphic sentinel node biopsy was verified against the gold standard of radical inguinal dissection. In particular, patients with enlarged lymph nodes have also been included since one half of these patients is known to have histologically negative lymph nodes. Between 2000 and 2004 fifteen patients with penile carcinoma were elected to undergo bilateral groin dissection, thus 30 inguinal areas have been dissected. Nine patients have had clinically palpable nodes. All patients underwent lymphoscintigraphy after injection of Tc99-nanocolloid subcutaneously into the peritumoral area. Intraoperatively the sentinel nodes were identified with the aid of a gamma ray detection probe and excised. Afterwards a standard groin dissection was performed and the different lymph nodes were histopathologically assessed separately. In all patients lymph nodes with high radioactivity uptake were detected bilaterally. In 10 out of 30 inguinal areas histopathologically positive lymph nodes were present. In four of them the sentinel node was positive for tumor but in six dissection areas lymph node metastases were found despite a negative sentinel node. These patients had clinically palpable lymph nodes in their histologically positive inguinal regions. If no palpable nodes were present dynamic sentinel biopsy detected the positive nodes. The current study showed that dynamic sentinel node biopsy in patients with clinically suspicious lymph nodes is of low value for detection of lymphatic spread in penile cancer. Therefore the gold standard in these patients remains the radical groin dissection. However, dynamic sentinel node biospy is still a promising strategy to identify lymphatic spreading in clinically N0 patients and therefore to prevent unnecessary groin dissection.     

Preoperative lymphoscintigraphy and dynamic sentinel node biopsy for staging penile cancer: results with pathological correlation

PURPOSE: We assessed the sensitivity of preoperative lymphoscintigraphy and dynamic sentinel node biopsy for staging the inguinal region of patients with penile cancer and no palpable inguinal adenopathy. MATERIALS AND METHODS: The records of 31 patients with invasive penile cancer and nonpalpable (29) or nonsuspicious (2) inguinal lymph nodes were reviewed. Preoperatively lymphoscintigraphy plus dynamic sentinel node biopsy with (99m)technetium labeled sulfur colloid and isosulfan blue dye was performed in 21 patients and dynamic sentinel node biopsy alone with blue dye only was done in 10. All patients underwent superficial lymph node dissection regardless of preoperative lymphoscintigraphy or dynamic sentinel node biopsy findings to establish pathological nodal status. RESULTS: Six of 32 groins that showed drainage on preoperative lymphoscintigraphy had inguinal node metastasis, as did 1 of 10 that was drainage negative. The sensitivity of preoperative lymphoscintigraphy drainage for cancer detection was 86%. Using dynamic sentinel node biopsy with blue dye plus radiotracer 5 sentinel lymph nodes were positive for cancer, although 2 false-negative results were obtained. Thus, the sensitivity of dynamic sentinel node biopsy per groin for cancer detection was 71%. CONCLUSIONS: In our experience preoperative lymphoscintigraphy and dynamic sentinel node biopsy as currently performed remain insufficient for detecting occult inguinal disease. Superficial lymph node dissection remains the gold standard for detecting inguinal microscopic metastasis in select patients.     

Lymphoscintigraphy with sentinel lymph node biopsy in cutaneous Merkel cell carcinoma.

Merkel cell carcinoma (MCC) is a rare cutaneous malignancy characterized by an aggressive clinical behavior with high rates of locoregional and systemic recurrence. Regional disease and distant metastases are associated with poor prognosis. Despite a predisposition of MCC to spread via the lymphatics, prophylactic lymph node dissection in the absence of clinically apparent lymph node involvement is controversial. The value of lymphoscintigraphy in cutaneous melanoma is established in lesions with ambiguous lymphatic drainage patterns. When used with sentinel lymph node biopsy (SLNB), it can identify subjects with occult regional node metastasis. The authors present 2 patients with MCC who underwent regional node staging with lymphoscintigraphy-directed SLNB. Both patients had sentinel nodes that were positive for metastatic disease. In patients with MCC, minimally invasive regional node staging SLNB may be useful in limiting the sequelae of routine lymphadenectomies. Whether early identification and treatment of patients with occult regional node disease can influence survival in MCC is not known.     

Anatomical mapping of lymphatic drainage in penile carcinoma with SPECT-CT: implications for the extent of inguinal lymph node dissection

BACKGROUND: Knowledge regarding the lymphatic drainage pattern of penile cancer is the basis for the extent of inguinal lymph node dissection for this disease. OBJECTIVE: To prospectively analyze the lymphatic drainage pattern of penile carcinoma using SPECT-CT and evaluate the implications for the extent of inguinal lymph node dissection. DESIGN, SETTING, AND PARTICIPANTS: The lymphatic drainage patterns of 50 patients scheduled for dynamic sentinel node biopsy were analyzed using a hybrid SPECT-CT scanner. MEASUREMENTS: A total of 86 clinically node-negative (cN0) inguinal and pelvic regions was evaluated. The sentinel and higher-tier nodes on SPECT-CT were divided into different zones in the groin and pelvic region. The groin was divided according to Daseler's five zones, four zones obtained by drawing a vertical and horizontal line over the saphenofemoral junction and one zone directly overlying this junction. The nodes in the pelvic region were classified into three zones: the external iliac/obturator zone, the common iliac zone, and the paraaortal zone. RESULTS AND LIMITATIONS: Lymphatic drainage was visualised in 82 of the 86 cN0 groins (95.3%). A total of 115 sentinel nodes and 182 higher-tier nodes was found. All sentinel nodes were located in superior and central inguinal zones. The higher-tier nodes were located in the groin and pelvic region. No lymphatic drainage was seen to the inferior two regions of the groin. A potential limitation of the study is that the unilateral lymphatic drainage seen in some patients could be normal, but it could also be caused by blockage of lymphatic drainage due to a grossly involved metastatic lymph node. Another possible limitation is that this study relies on the quality and accuracy of lymphoscintigraphy and the subsequent sentinel node procedure. CONCLUSIONS: All sentinel and higher-tier nodes were located in the superior and central inguinal zones and the pelvic region. No lymphatic drainage to the inferior inguinal zones was seen. This suggests that the extent of inguinal node dissection in cN0 patients could be reduced to removal of the superior and central inguinal zones. This may decrease the extensive morbidity associated with this procedure.     

Reoperative sentinel lymph node biopsy for ipsilateral breast tumor recurrence after previous axillary lymph node dissection: Report of a case

Sentinel lymph node biopsy has become a standard component of the evaluation of early-stage breast cancer, with a gradually increasing number of indications in this patient population. This report presents the case of a patient who underwent reoperative sentinel lymph node biopsy as part of an evaluation of ipsilateral breast tumor recurrence; she had previously undergone axillary lymph node dissection. Preoperative lymphoscintigraphy showed aberrant lymphatic drainage, and all three sentinel lymph nodes were positive for cancer. Although the optimal management of regional lymph nodes in patients with ipsilateral breast tumor recurrence who have already undergone axillary lymph node dissection has not been established, reoperative sentinel lymph node biopsy in this setting may therefore potentially enable the identification of subclinical, aberrantly located nodal metastasis.     

Lymphatic Mapping of the Breast: Locating the Sentinel Lymph Nodes

When the concept of sentinel lymph node biopsy was described in patients with melanoma, researchers quickly started to use lymphatic mapping techniques in breast cancer patients in an attempt to locate the sentinel node in the axilla. We have been performing mammary lymphoscintigraphy in this role for 6 years and have now studied 159 patients. Like others, we have found that most breast cancers (93%) have lymphatic drainage that includes the axilla, and we have found an average of 1.4 axillary sentinel nodes in these patients. Surgical biopsy of the axillary sentinel nodes accurately staged the node field in 96% of patients. We have also found, however, that the pattern of lymphatic drainage from the cancer site is unpredictable; and in 49% of patients lymphatic drainage occurred across the center line of the breast to axillary or internal mammary sentinel nodes. In more than half of our patients (56%) lymphatic drainage occurred to lymph nodes outside the axilla including the internal mammary (45%), supraclavicular (13%), and interpectoral and intramammary interval nodes (12%). These nodes are also sentinel nodes, and their presence indicates that a sentinel node biopsy procedure that stages only the status of the axillary lymph nodes has the potential to understage about half the patients with breast cancer. High quality lymphoscintigraphy allows accurate mapping of peritumoral lymphatic drainage in most patients with breast cancer. It is possible that in the future accurate nodal staging in each individual will involve biopsy of all sentinel lymph nodes, regardless of their location.     

Dynamic sentinel lymph node biopsy as the new paradigm for the management of penile cancer

ObjectivesThe management of patients with penile cancer who have high-risk features for micrometastasis with clinically negative inguinal lymph nodes is controversial. We describe the history of the sentinel lymph node biopsy and how it has evolved to become a useful adjunct in the management of penile caner.Materials and methodsUsing a PubMed search, we identified the evidence relating to the management of the inguinal lymph nodes in penile cancer between 1977 and 2010.ResultsThe concept of the sentinel lymph node (SLN) was first described in 1977 for penile carcinoma where lymphangiograms were performed via the dorsal lymphatics of the penis to locate the primary lymphatic drainage zone of the penis situated near the saphenofemoral junction. Then, in 1992, the lymphatic mapping concept was further advanced by performing intradermal injections of blue dye to directly visualize the lymphatic channels and SLN in the treatment of melanoma. In 1994, investigators from The Netherlands pioneered the use of dynamic sentinel lymph node biopsies (DSLNB) for penile cancer by combining the use of peri-lesional blue dye injection, lymphoscintigraphy, and other future modifications of the technique to achieve low false negative biopsy rates (4.8%) as well as much lower morbidity (5.7%), compared with the 30%–50% morbidity associated with a full inguinal node dissection.ConclusionDSLNB significantly decreases the morbidity associated with performing a standard or even modified inguinal lymph node dissection in patients with clinically negative inguinal lymph nodes. Performing DSLNB requires a multidisciplinary team of urologists, nuclear medicine radiologists, and pathologists working in cohesion to attain the best SLN detection rates with the lowest possible false-negative rates.     

Routine preoperative lymphoscintigraphy is not necessary prior to sentinel node biopsy for breast cancer.

BACKGROUND: This prospective study was performed to ascertain the added benefit of lymphoscintigraphy to a standard method of intraoperative lymphatic mapping and sentinel node biopsy for breast cancer. METHODS: Patients with invasive breast cancer were injected with 99mTc sulfur colloid prior to sentinel node biopsy; preoperative lymphoscintigraphy was then performed in half of the patient population. RESULTS: Sentinel node identification was possible in 45 of 50 patients (90%). All 14 patients (31%) with axillary nodal metastases had at least one histologically positive sentinel node (0% false negative rate). Lymphoscintigraphy revealed sentinel nodes in 17 of the 24 patients (70.8%) imaged. All 17 of these patients had one or more axillary sentinel nodes identified using intraoperative lymphatic mapping. In addition, 5 of 7 patients with a negative preoperative lymphoscintogram had an axillary sentinel lymph node(s) identified intraoperatively. None of the tumors showed drainage to the internal mammary lymph node chain by lymphoscintigraphy despite the fact that there were 5 patients with inner quadrant tumors. There was no significant advantage with respect to sentinel lymph node localization (91.7% versus 88.5%, P = not significant) or false negative rate (0%, both groups, P = not significant) in the group undergoing preoperative lymphoscintigraphy when compared with the patients in whom lymphoscintigraphy was not performed. CONCLUSIONS: Preoperative lymphoscintigraphy adds little additional information to intraoperative lymphatic mapping, and its routine use is not justified.     

Lymphatic mapping and sentinel node biopsy in gastric cancer

BACKGROUND: To determine the feasibility and significance of lymphatic mapping and sentinel lymph node biopsy (SLNB) in patients with gastric cancer. METHODS: From August 1999 to January 2002, 27 gastric cancer patients underwent lymphatic mapping and sentinel lymph node biopsy using isosulfan blue dye. RESULTS: The success rate of SLNB was 96.3% (26 of 27). Accuracy, sensitivity, and specificity were 100%. There were no false negatives. In 26 successful cases, 8 patients had positive sentinel lymph nodes and 18 had negative sentinel nodes. Of 8 patients with positive sentinel nodes, 6 had positive sentinel nodes only at N1 lymph node station, 1 only at N2 station, and 1 had positive sentinel nodes at both N1 and N2 stations. Of 18 patients with negative sentinel lymph nodes, 9 patients had sentinel nodes only at N1, 3 only at N2, 5 at both N1 and N2, and 1 at both N1 and N3. There were no cases in which sentinel lymph nodes were the only sites of metastases. CONCLUSIONS: Sentinel lymph node biopsy using isosulfan blue dye in gastric cancer is a feasible procedure with high sensitivity and accuracy. Sentinel lymph nodes demonstrate the varied lymphatic drainage. If the sentinel nodes at N2 are positive, it will guide surgeons to do a more extended lymph node dissection in early stage gastric cancer.     

Parotid selective lymphadenectomy in malignant melanoma.

Malignant melanoma of the head and neck can metastasize to lymph nodes within the parotid gland. Selective lymphadenectomy is the modern method of staging regional lymph node basins in clinically localized melanoma. This procedure involves intraoperative lymphatic mapping and directed, selective removal of the first draining nodes or sentinel lymph nodes (SLNs). Historically, the assessment of parotid lymph nodes would involve a superficial parotidectomy with facial nerve dissection. Since 1993, 28 patients with localized melanoma of the head and neck have demonstrated lymphatic drainage to parotid lymph nodes on preoperative lymphoscintigraphy. The overall success rate of parotid selective lymphadenectomy is 86% (24 of 28 patients). Of the 28 patients, there were 6 early patients in whom blue dye alone was utilized intraoperatively, and the success rate is 50% (3 of 6 patients). When blue dye and radiocolloid mapping techniques are combined, the parotid selective lymphadenectomy is successful in 95% of patients (21 of 22 patients). Four of the 24 patients (17%) had metastases to the SLNs and underwent therapeutic superficial parotidectomy and/or modified radical neck dissection. After completion of the therapeutic superficial parotidectomy, 1 of the 4 patients was found to have an additional parotid (nonsentinel) node with melanoma metastases. None of the patients incurred injury to the facial nerve by parotid selective lymphadenectomy. To date, 2 of 28 patients (7%) have had regional recurrence to the parotid gland. Failure of the SLN technique may occur when blue dye alone is used, when human serum albumin (not sulfur colloid) is the radiocolloid, when prior wide excision and skin graft is present before lymphatic mapping, and when all SLNs are not retrieved. We conclude that parotid selective lymphadenectomy is a safe and reliable alternative to superficial parotidectomy for staging clinically localized melanoma of the head and neck.     

Lymphatic mapping and detection of sentinel nodes in patients with bladder cancer

PURPOSE: We examined the possibility for detecting sentinel nodes in patients with bladder cancer and whether the histopathological status of identified sentinel nodes reflected that of the lymphatic field. MATERIALS AND METHODS: A total of 13 patients with bladder cancer who met the criteria qualifying them for radical cystectomy had intravesical injections of radioactive tracer and blue dye marker around the tumor followed by lymphoscintigraphy to visualize lymphatic drainage and detect sentinel nodes. Sentinel nodes were identified preoperatively by the blue color and increased radioactivity and were compared histopathologically with other routinely excised lymph nodes. RESULTS: Sentinel nodes were detected in 85% (11 of 13) of patients. There were 4 patients who had sentinel nodes containing tumor cells, and each metastasis was only seen in the detected sentinel node. There were no false-negative sentinel nodes. Of the metastatic sentinel nodes 3 were located outside the normally excised lymph nodes of the obturator fossa. CONCLUSIONS: Sentinel nodes can be detected in patients with bladder cancer. The histopathological status of the identified sentinel nodes was diagnostic for all other excised lymph nodes. Sentinel nodes often seem to be located outside the obturator lymphatic field, which is normally examined during preoperative staging of bladder cancer.     

Evaluation of dynamic lymphoscintigraphy and sentinel lymph-node biopsy for detecting occult metastases in patients with penile squamous cell carcinoma

OBJECTIVE: To evaluate the introduction of dynamic lymphoscintigraphy and sentinel lymph-node (SLN) biopsy (used to detect occult lymph node metastases in patients with penile cancer and clinically impalpable inguinal lymph nodes at presentation) at a UK tertiary referral centre for penile cancer. PATIENTS AND METHODS: In all, 75 patients with penile squamous cell carcinoma of stage T1, grade > or = 2, and unilateral or bilateral impalpable groin nodes, were prospectively enrolled over a 2-year period. Patients underwent lymphoscintigraphy with (99m)technetium-labelled nanocolloid which was injected intradermally around the tumour or into the distal penile shaft skin. Four hours later, the SLN(s) were identified during surgery using a hand-held gamma-probe and intradermal injections with blue dye. Completion lymph node dissection was subsequently used in patients with tumour-positive SLNs. RESULTS: In all, 255 SLNs were removed from 143 groins; all excised nodes had taken up the radioactive marker, and the blue dye was evident in 87%. Eighteen of 75 (24%) patients and 21 of 143 groins (15%) had a tumour-positive SLN. All but one patient went on to completion lymph node dissection. Three of these 18 (17%) had further disease in other than SLNs. Six of 143 (4%) groins developed minor complications. One false-negative result was reported at a median (range) follow-up of 11 (2-24) months. CONCLUSION: This technique is feasible for managing penile cancer in a UK tertiary referral centre. The initial results suggest that it can accurately identify the SLN(s), which can then be removed for pathological review with minimal morbidity.     

Is there a role for sentinel node biopsy in early N0 tongue tumors?

BACKGROUND: Detecting metastases to the cervical lymph nodes is the main problem in the management of squamous cell carcinoma of the tongue. We investigated the ability of sentinel node (SN) biopsy to predict neck status in 11 patients with lateral T1-T2, N0, and M0 squamous cell carcinoma of the tongue who underwent ipsilateral neck dissection 30 to 40 days after primary surgery. METHODS: In 5 patients, technetium 99m-labeled particles were injected close to the operation scar on the day before neck dissection, and the labeled neck nodes were revealed by lymphoscintigraphy. The next 6 patients underwent lymphoscintigraphy both before surgery and before neck dissection. During neck dissection, the ipsilateral SNs were identified by using a hand-held probe and removed separately. RESULTS: Three patients (27%) had metastatic neck nodes. In all cases, labeled nodes were revealed by scintigraphy. Ipsilateral SNs were removed from 8 patients and correctly predicted the state of the neck (6 negatives and 2 positives). Lymphoscintigraphy before and after surgery revealed that drainage was modified after surgery in 5 of 6 patients; the pre-surgery drainage pattern varied markedly among the 5 pN0 patients. CONCLUSIONS: The technique allows easy and safe identification of SNs and shows promise in guiding selective neck dissection. Surgery on the primary tumor often modifies lymphatic drainage, so that SN biopsy may only be useful if the primary operation and neck dissection are performed at the same time.     

Sentinel lymph node dissection for primary cutaneous melanoma: a community hospital's initial experience

Management of the regional lymph nodes remains the most controversial aspect of treating patients with intermediate-thickness cutaneous melanoma. Prospective studies have failed to demonstrate a significant survival advantage for patients undergoing elective lymph node dissection. The sentinel lymph node dissection (SLND) technique has been proposed as a method of accurately identifying patients with occult metastases in whom a regional lymph node dissection would be indicated. The majority of studies evaluating this technique have come from academic centers, most with dedicated melanoma clinics. This report describes the initial experience with SLND at a community hospital. Fifteen patients with intermediate-thickness primary cutaneous melanoma underwent preoperative lymphoscintigraphy with 99Tc-sulfur colloid. In addition, intraoperative lymphatic mapping using intradermally injected isosulfan blue was performed. Dissection was guided by radioactivity levels (in counts per second) as measured by a hand-held gamma probe. The resected lymph node or nodes were evaluated for micrometastases using routine hematoxylin and eosin staining and immunohistochemistry with S-100 and HMB-45. All patients were followed clinically for any evidence of recurrence. A sentinel node(s) was identified on preoperative lymphoscintigraphy in all 15 patients (100%). A single sentinel node was identified in 11 of 15 (73%), two nodes in 3 (20%), and one node in 1 (6.7%). The hand-held gamma probe reading correlated well with the site marked the "hot spot" (600-15,320 cps for the hot spot versus 10-350 cps for background). The sentinel lymph node was successfully identified and resected in all 15 patients. Blue-stained lymphatics and/or lymph nodes were present in 8 of 15 (53%) cases. Histopathology was negative for evidence of occult micrometastases in all patients. At mean follow-up of 221 days, all 15 patients remain with no evidence of disease. The outcomes for mapping and harvesting the sentinel node at a community institution compare favorably with results at major academic institutions. SLND may therefore be offered to patients with intermediate-thickness cutaneous melanoma in the community hospital setting with regional lymph node dissection and adjuvant interferon alpha-2b as options for patients with nodal micrometastases.     

Size of metastasis in the sentinel node predicts additional nodal involvement in penile carcinoma

PURPOSE: The majority of patients with penile cancer with a tumor positive sentinel node do not benefit from complementary lymph node dissection because of absent additional involved nodes. We analyzed factors that may determine the involvement of additional nodes. MATERIALS AND METHODS: A total of 158 patients with clinically node negative penile carcinoma underwent sentinel node biopsy. Complementary inguinal lymph node dissection was performed when the sentinel node was tumor positive. The size of the sentinel node metastasis was measured and classified as micrometastasis--2 mm or less, or macrometastasis--more than 2 mm. Sentinel and dissection specimen nodes were step-sectioned. Factors were analyzed for their association with additional nodal involvement, including stage, diameter, grade, absence or presence of vascular invasion of the primary tumor, and sentinel node metastasis size. RESULTS: Tumor positive sentinel nodes were found in 46 groins and complementary lymph node dissection was performed. Nine of these 46 groins (20%) contained additional involved lymph nodes. On univariate and multivariate analyses the size of the sentinel node metastasis proved to be the only significant prognostic variable for additional lymph node involvement (each p = 0.02). None of the 15 groins with only micrometastasis in the sentinel node contained additional involved nodes. CONCLUSIONS: In penile carcinoma additional nodal involvement was related to the size of the metastasis in the sentinel node. Sentinel node micrometastasis was not associated with other involved lymph nodes. This finding suggests that these patients can be spared complementary lymph node dissection.     

Radioisotope guided pelvic lymph node dissection for prostate cancer

PURPOSE: The localization of lymph node metastases in prostate cancer varies enormously. Due to high morbidity complete pelvic lymphadenectomy is often decreased to modified staging lymphadenectomy, resulting in loss of sensitivity for detecting micrometastases. Based on the promising results of intraoperative gamma probe application for identifying sentinel lymph nodes in malignant melanoma, breast and penis cancer, we identified sentinel lymph nodes in prostate cancer using a comparable technique. MATERIALS AND METHODS: In 117 patients 99mtechnetium nanocolloid was transrectally injected directly into the prostate under ultrasound guidance 1 day before pelvic lymphadenectomy. Thereafter dynamic lymphoscintigraphy was done. Initially lymph nodes identified as sentinel lymph nodes by the gamma probe were removed and subsequently modified pelvic lymphadenectomy was performed. RESULTS: Lymphatic metastasis was detected in 28 cases. An average of 4 sentinel lymph nodes were identified per patient in 25 of 27 patients with micrometastasis, of which those in 24 contained micrometastasis for 96% sensitivity. In contrast, sensitivity of modified pelvic lymphadenectomy was 81.5%. In 16 patients only sentinel lymph nodes were positive. An average of 21.8 lymph nodes (range 10 to 51) was dissected per patient at pelvic lymphadenectomy. Lymph node metastasis was noted in 6 of the 46 patients with a prostate specific antigen between 4 and 10 ng./ml. and in 8 of the 64 with a stage pT2 tumor. CONCLUSIONS: Our study shows individual variability of lymphatic drainage of the prostate and limited sensitivity for detecting positive lymph nodes when the pelvic dissection area is limited. Furthermore, our experience implies that the identification of sentinel lymph nodes is feasible, not only in breast cancer and malignant melanoma, but also in prostate cancer using a comparable technique.     

淋巴闪烁显像与乳腺癌前哨淋巴结活检

乳腺癌前哨淋巴结的精确定位是乳腺癌前哨淋巴结活检成功的先决条件之一,明确乳腺淋巴引流途径对乳腺癌前哨淋巴结的准确定位有重要指导意义。术前淋巴闪烁显像可提供个体化的淋巴引流特点,有助于确定前哨淋巴结的位置、数目及是否存在腋窝外前哨淋巴结。现对淋巴闪烁显像在乳腺癌前哨淋巴结活检中的应用现状和存在的问题进行综述。     

Lymphatic mapping and intraoperative lymphoscintigraphy for identifying the sentinel node in penile tumors

Lymph node mapping has become an integral part of the management of melanoma and breast cancer with regard to both staging and treatment. We report our technique for lymphatic mapping and intraoperative lymphoscintigraphy applied to a patient with penile melanoma. This technique may improve the sensitivity of identifying the sentinel lymph node in patients with malignant penile lesions.