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.     

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.     

Reliability and safety of current dynamic sentinel node biopsy for penile carcinoma

OBJECTIVES: Dynamic sentinel node biopsy (DSNB) has been performed at our department since 1994 to assess status of inguinal lymph nodes of clinically node-negative (cN0) patients with penile carcinoma. Over time, several modifications were made to reduce the false-negative rate and thus increase sensitivity. We compared the false-negative and complication rates of the current procedure, as performed at our institute since 2001, with the prior procedures. MATERIALS AND METHODS: The patients who underwent DSNB for penile carcinoma in the period from 1994 until July 2004 were divided into two cohorts: cohort A: patients treated from 1994 until 2001; cohort B: patients treated from 2001 until 2004. Cohort A consisted of 92 patients, in whom 157 groins were explored. Cohort B consisted of 58 patients, with a total of 105 explored groins. Medians for follow-up in cohorts A and B were 83 (range: 24-130) and 30 (range: 24-49) mo, respectively. The false-negative and complication rates were determined in both cohorts. RESULTS: In cohort A, 21 of 157 explored groins contained tumour-positive sentinel nodes, and five false-negative procedures were encountered, resulting in a false-negative rate of 19.2%. In cohort B, 20 of 105 explored groins contained tumour-positive sentinel nodes, and one procedure was false-negative. The false-negative rate was 4.8%. The rate of complications dropped from 10.2% in cohort A to 5.7% in cohort B. All complications were minor and transient. CONCLUSIONS: The false-negative and complication rates of DSNB have decreased since the procedure was modified. The current procedure has false-negative and complication rates of 4.8% and 5.7%, respectively. DSNB has matured into a reliable and safe method for assessing status of lymph nodes in cN0 penile carcinoma patients.     

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.     

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.     

Repeat dynamic sentinel node biopsy in locally recurrent penile carcinoma

Study Type – Diagnosis (case series)
Level of Evidence 4

OBJECTIVE

To explore the role of repeat dynamic sentinel‐node biopsy (SNB) in clinically node‐negative patients with locally recurrent penile carcinoma after previous penile surgery and SNB.

PATIENTS AND METHODS

Between 1994 and 2008, 12 patients (4% of the 304 in our prospectively maintained dynamic sentinel node database) with clinically node‐negative groins had a repeat SNB for locally recurrent penile carcinoma after previous penile surgery and SNB. Five of these patients had previously had a unilateral inguinal node dissection for groin metastases. The median disease‐free interval was 18 months. The protocol and technique of primary dynamic SNB and the repeat procedure were similar, including preoperative lymphoscintigraphy and blue‐dye injection. Completion inguinal node dissection was only done if there was an involved sentinel node.

RESULTS

No sentinel nodes were seen on preoperative lymphoscintigraphy in the five groins that had previously been dissected. A sentinel node was visualized on lymphoscintigraphy in the remaining 19 undissected groins. In 15 of these groins (79%) the sentinel node was identified during surgery. Histopathological analysis showed involved sentinel nodes in four groins of three patients. Additional metastatic nodes were found in one completion inguinal lymph node dissection specimen. During a median follow‐up of 32 months after the repeat SNB, one patient developed a groin recurrence 14 months after a tumour‐negative sentinel node procedure.

CONCLUSIONS

Repeat dynamic SNB is feasible in clinically node‐negative patients with locally recurrent penile carcinoma despite previous SNB.     

Morbidity of dynamic sentinel node biopsy in penile carcinoma

PURPOSE: We report on the morbidity of dynamic sentinel lymph node biopsy (DSNB) in penile squamous cell carcinoma (SCC). MATERIALS AND METHODS: Between 1994 and 2003 DSNB was performed in 129 patients with T2 or T3 penile SCC who had 243 clinically node negative groins. Patients with groins with a tumor positive sentinel node underwent additional standard inguinal lymphadenectomy. RESULTS: A total of 285 sentinel nodes were harvested in 223 explored groins. The sentinel nodes were tumor-free in 189 groins. A total of 34 standard inguinal lymphadenectomies were performed because of a tumor positive sentinel node. There were 6 regional relapses during a median followup of 50 months (range 5 to 124) resulting in a false-negative rate of 15% (6 of 40 groins). This rate was 17% when calculated per patient (6 of 35 patients). Early and/or late complications following DSNB only occurred in 7% (14 of 189) of the groins. After DSNB followed by a standard inguinal lymphadenectomy, the rate was 68% (23 of 34). All complications of DSNB were minor and easily managed. CONCLUSIONS: Morbidity of DSNB in penile SCC is low. However, an in field recurrence after a negative DSNB is perhaps the greatest complication of the procedure.     

Prognostic Factors for Occult Inguinal Lymph Node Involvement in Penile Carcinoma and Assessment of the High-Risk EAU Subgroup: A Two-Institution Analysis of 342 Clinically Node-Negative Patients

Background

The European Association of Urology (EAU) guidelines advise an elective bilateral lymphadenectomy in clinically node-negative (cN0) patients with high-risk penile carcinoma (≥pT2, G3, or lymphovascular invasion [LVI]).

Objective

Our aim was to assess prognostic factors for occult metastasis and to determine whether current EAU guidelines accurately stratify patients at high risk.

Design, setting, and participants

Data of 342 cN0 patients with histologically proven invasive penile squamous cell carcinoma who had undergone the current dynamic sentinel node biopsy (DSNB) protocol were analysed. A complete ipsilateral inguinal lymphadenectomy was only done if the sentinel node was tumour positive.

Measurements

The presence of occult metastasis was established by preoperative ultrasound and tumour-positive fine-needle aspiration cytology, tumour-positive sentinel nodes, and groin metastases during follow-up after a negative DSNB procedure. Median follow-up was 31 mo.

Results and limitations

Sixty-eight of 342 patients (20%) and 87 of 684 groins (13%) had occult nodal involvement including 6 patients (2%) with a groin metastasis after negative DSNB. Corpus spongiosum invasion, corpus cavernosum invasion, histologic grade, and LVI were each significant prognosticators for occult metastasis on univariate analysis. On multivariate analysis, grade (odds ratio [OR]: 3.3 for intermediate and 4.9 for poor, respectively) and LVI (OR: 2.2) remained predictive factors. In total, 245 patients (72%) were classified high risk according to EAU guidelines. Among them, the incidence of occult metastasis was 23% (57 of 245). A potential limitation of this study is the lack of external review.

Conclusions

Histologic grade and LVI are independent prognostic factors for occult metastasis in penile carcinoma. Although both predictors are incorporated into the current EAU guidelines, the stratification of patients needing a lymph node dissection is inaccurate. Approximately 77% of high-risk patients (188 of 245) would have had a negative bilateral inguinal lymphadenectomy. For the time being, DSNB is considered a more suitable staging method than EAU risk stratification for an accurate determination of patients who require lymph node dissection.     

Sentinel node biopsy with technetium-99m colloidal rhenium sulphide in patients with breast cancer

BACKGROUND: Sentinel node biopsy is emerging as a technique to replace routine axillary lymph node dissection. The lymphatic mapping technique is still at a developmental stage and no standard technique exists. This study used technetium-99m colloidal rhenium sulphide with a mean particle size of 100 (range 50-200) nm for sentinel node mapping. METHODS: Eighty-seven patients with breast cancer, but no clinical evidence of axillary metastasis, were studied. One day before operation technetium-99m colloidal rhenium sulphide was injected at four points into breast tissue surrounding the tumour. Lymphoscintigraphy was performed 2 h after injection, and surgery was usually performed after 20 h. A hand-held gamma probe guided sentinel node biopsy. RESULTS: Lymphoscintigraphy revealed axillary hot spots in all patients. During operation, the sentinel node was identified in all 87 patients (100 per cent). The number of sentinel nodes per patient ranged from 1 to 5 (mean 2). Metastatic sentinel nodes were identified in 37 of 87 patients. There were no false negatives. CONCLUSION: This study suggests that technetium-99m rhenium sulphide is a suitable agent for sentinel node mapping in patients with breast cancer.     

Nodal Staging in Penile Carcinoma by Dynamic Sentinel Node Biopsy After Previous Therapeutic Primary Tumour Resection

Background

Dynamic sentinel node biopsy (DSNB) is used to evaluate the nodal status of patients with penile carcinoma and clinically node-negative groins. This minimally invasive procedure is usually done at the same time as the treatment of the primary tumour.

Objective

Our aim was to evaluate results of so-called postresection DSNB, that is, DSNB after previous resection of the penile tumour.

Design, setting, and participants

All 40 patients who had undergone DSNB after previous penile carcinoma resection with histopathologically tumour-negative margins between February 2003 and July 2009 were analysed. Twenty patients (50%) had known unilateral nodal involvement, and DSNB was used to stage the clinically normal contralateral groin. Hence the study concerned 60 groins without palpable nodes. The median time between primary tumour resection and DSNB was 2.8 mo. The technique of postresection DSNB was similar to the standard procedure.

Measurements

The sentinel node visualisation rate, identification rate, histopathologic results, and outcome during follow-up were investigated.

Results and limitations

A sentinel node was visualised on the lymphoscintigrams of 56 of the 60 eligible groins (93%). A sentinel node was identified intraoperatively in all these 56 groins. A median of two sentinel nodes were removed. Histopathologic analysis revealed involvement of seven groins (12%) in seven patients (18%). The median size of these metastases was 6 mm. Additional dissemination was found in one completed ipsilateral inguinal node dissection specimen. No recurrences developed in the groins from which one or more tumour-free sentinel nodes had been taken during a median follow-up of 28 mo after the primary tumour resection. A potential limitation of this study is the short follow-up and relatively small cohort number.

Conclusions

Postresection DSNB is a suitable procedure to stage clinically node-negative penile carcinoma after previous therapeutic primary tumour resection. The results seem similar to the favourable experience with DSNB in patients with their tumour still present.     

Reproducibility of lymphoscintigraphy for lymphatic mapping in patients with penile carcinoma

PURPOSE: We evaluated the reproducibility of lymphoscintigraphy in the assessment of the location and number of sentinel nodes in patients with penile carcinoma. MATERIALS AND METHODS: A total of 20 patients were prospectively included in analysis. Lymphoscintigraphy was performed after intradermal injection of technetium nanocolloid around the tumor or excision scar. We performed 10-minute anterior dynamic imaging, and static anterior and lateral images were obtained at 30 minutes and 2 hours. The following day scintigraphy was repeated after a second injection of the radiolabeled colloid given in an identical fashion, preceded by acquisition of a starting image. An observer evaluated the paired images and count rates were calculated from the images. RESULTS: At least 1 sentinel node was visualized in all patients on the first lymphoscintigram. A total of 56 sentinel nodes were seen in 38 basins. Drainage to both groins was seen in 18 patients. In 1 of these patients drainage to the prepubic area was also observed. There were 2 patients with drainage to 1 groin. The second lymphoscintigram revealed the same drainage pattern in all patients- the same number of nodal basins and number of sentinel nodes were visualized at identical locations. All hotspots that were visualized during the first lymphoscintigram showed an unequivocal increase in radioactivity after repeat injection. Thus, the reproducibility of penile lymphoscintigraphy was 100% (95% CI 85%-100%). The Pearson correlation coefficient of the paired count rates was 0.69 (p <0.0001). CONCLUSIONS: Results of lymphoscintigraphy in patients with penile carcinoma are highly reproducible for assessment of the number and location of sentinel nodes.     

Detection of occult metastasis in squamous cell carcinoma of the penis using a dynamic sentinel node procedure

PURPOSE: We evaluated the so-called dynamic sentinel node procedure in patients with penile cancer. This new staging technique consists of excisional biopsy of the first lymph node onto which a tumor drains the so-called sentinel node, based on individual mapping of lymphatic drainage. MATERIALS AND METHODS: From 1994 to 1998, 55 consecutive patients with stage T2 or greater bilateral or unilateral node negative squamous cell carcinoma of the penis were prospectively entered in this study. Tumor stage was T2N0 in 42, T2N1 in 4 and T3N0 in 9 cases. To locate the sentinel node each patient underwent lymphoscintigraphy with 99mtechnetium nanocolloid injected intradermally around the tumor. The following day the sentinel node was identified intraoperatively using patent blue dye injected intradermally around the tumor and a gamma detection probe. Regional lymph node dissection was restricted to patients with a tumor positive sentinel node only. RESULTS: Scintigraphy revealed 125 sentinel nodes in 107 inguinal regions, including no sentinel node in 2 patients, 1 or more unilateral nodes in 10 and bilateral drainage in 43. At surgery 108 sentinel nodes were removed. In 8 patients with 2 or more sentinel nodes on lymphoscintigraphy only 1 was noted intraoperatively and in 9 an additional sentinel node was removed, which was not identified by scintigraphy. All nodes were identified with the gamma detection probe. In 1 patient a wound abscess developed. Regional lymph node dissection was performed in 11 patients with sentinel node metastasis. Median followup was 22 months (range 4.1 to 61). In 1 patient lymph node metastasis was noted at followup despite prior excision of a tumor-free sentinel node. CONCLUSIONS: The dynamic sentinel node procedure is a promising staging technique to detect early metastatic dissemination of penile cancer based on individual mapping of lymphatic drainage, and enables identification of patients with clinically node negative disease requiring regional lymph node dissection.     

High incidence of in-transit metastases after sentinel node biopsy in patients with melanoma

BACKGROUND: The occurrence of in-transit metastases in patients with a tumour-positive sentinel node varies greatly between centres and it has been suggested that the incidence is high in this patient group. METHODS: The incidence of in-transit metastases in 61 patients who had lymph node dissection because of a tumour-positive sentinel node was compared with that in 60 patients who had palpable nodal metastases dissected. RESULTS: The incidence of in-transit metastases was 23 per cent in patients with a positive sentinel node and 8 per cent in those with palpable nodes (P = 0.027). CONCLUSION: Sentinel node biopsy was associated with a higher risk of in-transit metastases. This finding does not support the routine use of sentinel node biopsy in the management of melanoma.     

The use of lymphoscintigraphy and PET in the management of head and neck melanoma.

OBJECTIVES: Lymphoscintigraphy with sentinel node dissection and 18 fluoro-2-deoxyglucose positron emission tomography (PET) are being used independently in the management of many intermediate and thick melanomas of the head and neck. We report a series of patients with melanoma of the head and neck with Breslow depths greater than 1.0 mm and clinically negative regional nodes that were evaluated prospectively with PET and lymphoscintigraphy. STUDY DESIGN AND SETTING: Between July 1, 1998 and December 30, 2000 PET scans were obtained preoperatively on 18 patients undergoing resection of head and neck melanoma. Lymphoscintigraphy and sentinel node dissection was performed. Resection of the primary lesion was then carried out with adequate margins and the defects were reconstructed. RESULTS: Sentinel node(s) were found in 17/18 patients (94.4%); 5/18 (27.8%) of cases had metastases. PET detected nodal metastasis preoperatively in 3 patients (16.7%), one of which had a positive sentinel node dissection. CONCLUSION: PET and lymphoscintigraphy offer complimentary ways of evaluation for metastatic melanoma.     

亚甲蓝检测阴茎癌前哨淋巴结在腹股沟淋巴结清扫中的意义

目的:探讨亚甲蓝检测阴茎癌前哨淋巴结(SN)在腹股沟淋巴结清扫中的意义。方法:22例阴茎癌患者采取阴茎原发病灶切除同时,采用亚甲蓝检测腹股沟SN作活检,并选择SN转移病例及时行该侧腹股沟区淋巴结清扫术,计算该方法的准确度,假阴性率。结果:95%(21/22)的患者术中可检测到SN,19例患者两侧均可检测到SN,2例为单侧。21例患者中40枚SN,其中阳性淋巴结11例(27.5%)。4例腹股沟SN阴性患者在随访中出现腹股沟淋巴结或盆腔淋巴结转移。亚甲蓝在检查阴茎癌SN阳性预测率100%,准确度81%,其中假阴性率28%。结论:本方法术前准备简单,操作方便,费用较低,可作为一种经济有效的检测方式。     

A Meta-analysis of the Prognostic Significance of Sentinel Lymph Node Status in Merkel Cell Carcinoma

BACKGROUND: Merkel cell carcinoma is an aggressive cutaneous neoplasm with a high propensity to metastasize to lymph nodes. OBJECTIVE: The objective of this study was to determine the prognostic significance of sentinel lymph node status in patients with Merkel cell carcinoma. METHODS: A meta-analysis of case series of patients with Merkel cell carcinoma managed with sentinel lymph node biopsy was performed. RESULTS: Forty of 60 patients (67%) had a biopsy-negative sentinel lymph node; 97% of this group had no recurrence at 7.3 months median follow-up. Twenty patients (33%) had a biopsy-positive sentinel lymph node; 33% of this group experienced local, regional, or systemic recurrence at 12 months median follow-up. Risk of recurrence or metastasis was 19-fold greater in biopsy-positive patients (odds ratio, 18.9; p = 0.005). None of 15 biopsy-positive patients who underwent therapeutic lymph node dissection experienced a regional recurrence; 3 of 4 who did not receive therapeutic lymphadenectomy experienced regional recurrence. CONCLUSION: Sentinel lymph node positivity is strongly predictive of a high short-term risk of recurrence or metastasis in patients with Merkel cell carcinoma. Therapeutic lymph node dissection appears effective in preventing short-term regional nodal recurrence. Aggressive adjuvant treatment should be considered for patients with positive sentinel lymph nodes.     

Reliability of sentinel lymph node biopsy with squamous cell carcinoma of the oral cavity.

OBJECTIVES: Although sentinel lymph node biopsy (SLNB) may reduce surgery-related complications related to unnecessary lymph node dissection and is now widely used for many patients with cutaneous melanoma and breast cancer, its use for oral cancer patients remains controversial. One of the main reasons for the reluctance to initiate SLNB for oral cancer is that the frequency of skip metastasis has not been clarified. The objectives of this study are to examine the frequency of skip metastasis and to evaluate SLNB for oral cancer. STUDY DESIGN: To shed light on these concerns, we first conducted a retrospective study of 296 patients with squamous cell carcinoma of the oral cavity who underwent neck dissection. Next, the accuracy of lymph node biopsy with and without detecting sentinel lymph node was examined. RESULTS: Ten patients showed skip neck metastasis in the level III-V region without level I-II involvement. Of these patients, 7 underwent neck dissection when their initially N0 neck progressed to N+, 2 underwent neck dissection when local recurrence occurred, and only 1 underwent surgery as an initial therapy. Most patients who underwent neck dissection as the initial therapy showed skip metastasis. Intraoperative lymph node biopsy without any attempt to detect sentinel lymph nodes by means of blue dye or lymphoscintigraphy was performed on 68 patients with oral cancer. Sixty-one (90%) were diagnosed correctly, whereas 7 diagnosed as N- actually had neck metastasis. SLNB with blue dye was performed on 21 patients. In 17 of them, sentinel lymph node was easily detected, resulting in a correct diagnosis for 16 patients (94%), while 1 with a false negative result actually had micrometastasis. CONCLUSION: These findings seem to suggest that SLNB is useful and can be applied to patients with oral cancer who undergo surgery as the initial therapy.     

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.     

Sentinel nodes outside lymph node basins in patients with melanoma

BACKGROUND: Lymphoscintigraphy occasionally reveals hot spots outside lymph node basins in patients with melanoma. The aim of this study was to evaluate such abnormally located hot spots. METHODS: Sentinel node biopsy was studied prospectively in 379 patients with clinically localized cutaneous melanoma. One day after lymphoscintigraphy, sentinel node biopsy was performed guided by vital blue dye and a gamma ray detection probe. RESULTS: Persisting hot spots outside the regional node basins were seen in 25 patients (6.6 per cent). Several specific drainage patterns were discerned. In five patients, aberrant sentinel nodes were not explored. The hot spot represented a lymphangioma in two patients. Radioactive lymph nodes were identified in the remaining 18 patients (4.7 per cent). Four patients had metastasis in one of these aberrant lymph nodes. CONCLUSION: Sentinel nodes were found outside a lymph node basin in 5 per cent of patients. Particular drainage patterns exist. It is recommended to incorporate such sites in the late scintigraphy images and to pursue aberrant sentinel nodes, as they may be the only sites of metastasis.     

Detection of sentinel lymph nodes in patients with papillary thyroid cancer

OBJECTIVES: To determine the feasibility of sentinel lymph node biopsy as a means of evaluating the cervical lymph nodes of patients with papillary thyroid cancer. METHODS: Isosulfan blue dye was injected around the tumour of 68 patients with papillary thyroid cancer; sentinel lymph node biopsy was performed in addition to subtotal thyroidectomy and central and modified lateral neck lymph node dissections. Surgical specimens were examined by routine processing to determine whether metastasis was present. RESULTS: Sentinel lymph nodes were identified in 63 (92.6%) of the 68 patients. There was concordance between the sentinel lymph node status and the final regional lymph node status in 58 (92.1%) of the 63 patients. There were five false-negative cases. Sentinel lymph node biopsy had a sensitivity of 87.5% (35/40), specificity of 100% (23/23), positive predictive value of 100% (35/35), negative predictive value of 82.1% (23/28), and accuracy of 92.1% (58/63). CONCLUSIONS: Sentinel lymph node biopsy may allow discrimination between patients with true lymph-node-negative papillary thyroid carcinoma and those with non-palpable metastatic lymph nodes. It may also be helpful in diagnosing metastases and avoiding unnecessary lymph node dissection in thyroid cancer.