Detection of Sentinel Nodes by Lymphoscintigraphy and Gamma Probe Guided Surgery in Vulvar Neoplasia

Lymphoscintigraphy and sentinel lymph node biopsy in vulvar carcinoma: update from a European expert panel

PURPOSE

This study aimed to update the clinical practice applications and technical procedures of sentinel lymph node (SLN) biopsy in vulvar cancer from European experts.

METHODS

A systematic data search using PubMed/MEDLINE database was performed up to May 29, 2019. Only original studies focused on SLN biopsy in vulvar cancer, published in the English language and with a minimum of nine patients were selected.

RESULTS

Among 280 citations, 65 studies fulfilled the inclusion criteria. On the basis of the published evidences and consensus of European experts, this study provides an updated overview on clinical applications and technical procedures of SLN biopsy in vulvar cancer.

CONCLUSIONS

SLN biopsy is nowadays the standard treatment for well-selected women with clinically negative lymph nodes. Negative SLN is associated with a low groin recurrence rate and a good 5-year disease-specific survival rate. SLN biopsy is the most cost-effective approach than lymphadenectomy in early-stage vulvar cancer. However, future trials should focus on the safe extension of the indication of SLN biopsy in vulvar cancer. Although radiotracers and optical agents are widely used in the clinical routine, there is an increasing interest for hybrid tracers like indocyanine-^99mTc-nanocolloid. Finally, it is essential to standardise the acquisition protocol including SPECT/CT images, and due to the low incidence of this type of malignancy to centralise this procedure in experienced centres for personalised approach.

Sentinel node assessment for diagnosis of groin lymph node involvement in vulval cancer

BACKGROUND

Vulval cancer is usually treated by wide local excision with removal of groin lymph nodes (inguinofemoral lymphadenectomy) from one or both sides, depending on the tumour location. However, this procedure is associated with significant morbidity. As lymph node metastasis occurs in about 30% of women with early vulval cancer, accurate prediction of lymph node metastases could reduce the extent of surgery in many women, thereby reducing morbidity. Sentinel node assessment is a diagnostic technique that uses traceable agents to identify the spread of cancer cells to the lymph nodes draining affected tissue. Once the sentinel nodes are identified, they are removed and submitted to histological examination. This technique has been found to be useful in diagnosing the nodal involvement of other types of tumours. Sentinel node assessment in vulval cancer has been evaluated with various tracing agents. It is unclear which tracing agent or combination of agents is most accurate.

OBJECTIVES

To assess the diagnostic test accuracy of various techniques using traceable agents for sentinel lymph node assessment to diagnose groin lymph node metastasis in women with FIGO stage IB or higher vulval cancer and to investigate sources of heterogeneity.

SEARCH METHODS

We searched MEDLINE (1946 to February 2013), EMBASE (1974 to March 2013) and the relevant Cochrane trial registers.

SELECTION CRITERIA

Studies that evaluated the diagnostic accuracy of traceable agents for sentinel node assessment (involving the identification of a sentinel node plus histological examination) compared with histological examination of removed groin lymph nodes following complete inguinofemoral lymphadenectomy (IFL) in women with vulval cancer, provided there were sufficient data for the construction of two-by-two tables.

DATA COLLECTION AND ANALYSIS

Two authors (TAL, AP) independently screened titles and abstracts for relevance, classified studies for inclusion/exclusion and extracted data. We assessed the methodological quality of studies using the QUADAS-2 tool. We used univariate meta-analytical methods to estimate pooled sensitivity estimates.

MAIN RESULTS

We included 34 studies evaluating 1614 women and approximately 2396 groins. The overall methodological quality of included studies was moderate. The studies included in this review used the following traceable techniques to identify sentinel nodes in their participants: blue dye only (three studies), technetium only (eight studies), blue dye plus technetium combined (combined tests; 13 studies) and various inconsistent combinations of these three techniques (mixed tests; 10 studies). For studies of mixed tests, we obtained separate test data where possible.Most studies used haematoxylin and eosin (H&E) stains for the histological examination. Additionally an immunohistochemical (IHC) stain with and without ultrastaging was employed by 14 and eight studies, respectively. One study used reverse transcriptase polymerase chain reaction analysis (CA9 RT-PCR), whilst three studies did not describe the histological methods used.The pooled sensitivity estimate for studies using blue dye only was 0.94 (68 women; 95% confidence interval (CI) 0.69 to 0.99), for mixed tests was 0.91 (679 women; 95% CI 0.71 to 0.98), for technetium only was 0.93 (149 women; 95% CI 0.89 to 0.96) and for combined tests was 0.95 (390 women; 95% CI 0.89 to 0.97). Negative predictive values (NPVs) for all index tests were > 95%. Most studies also reported sentinel node detection rates (the ability of the test to identify a sentinel node) of the index test. The mean detection rate for blue dye alone was 82%, compared with 95%, 96% and 98% for mixed tests, technetium only and combined tests, respectively. We estimated the clinical consequences of the various tests for 100 women undergoing the sentinel node procedure, assuming the prevalence of groin metastases to be 30%. For the combined or technetium only tests, one and two women with groin metastases might be 'missed', respectively (95% CI 1 to 3); and for mixed tests, three women with groin metastases might be 'missed' (95% CI 1 to 9). The wide CIs associated with the pooled sensitivity estimates for blue dye and mixed tests increased the potential for these tests to 'miss' women with groin metastases.

AUTHORS' CONCLUSIONS

There is little difference in diagnostic test accuracy between the technetium and combined tests. The combined test may reduce the number of women with 'missed' groin node metastases compared with technetium only. Blue dye alone may be associated with more 'missed' cases compared with tests using technetium. Sentinel node assessment with technetium-based tests will reduce the need for IFL by 70% in women with early vulval cancer. It is not yet clear how the survival of women with negative sentinel nodes compares to those undergoing standard surgery (IFL). A randomised controlled trial of sentinel node dissection and IFL has methodological and ethical issues, therefore more observational data on the survival of women with early vulval cancer are needed.

The EANM clinical and technical guidelines for lymphoscintigraphy and sentinel node localization in gynaecological cancers

The accurate harvesting of a sentinel node in gynaecological cancer (i.e. vaginal, vulvar, cervical, endometrial or ovarian cancer) includes a sequence of procedures with components from different medical specialities (nuclear medicine, radiology, surgical oncology and pathology). These guidelines are divided into sectione entitled: Purpose, Background information and definitions, Clinical indications and contraindications for SLN detection, Procedures (in the nuclear medicine department, in the surgical suite, and for radiation dosimetry), and Issues requiring further clarification. The guidelines were prepared for nuclear medicine physicians. The intention is to offer assistance in optimizing the diagnostic information that can currently be obtained from sentinel lymph node procedures. If specific recommendations given cannot be based on evidence from original scientific studies, referral is made to "general consensus" and similar expressions. The recommendations are designed to assist in the practice of referral to, and the performance, interpretation and reporting of all steps of the sentinel node procedure in the hope of setting state-of-the-art standards for high-quality evaluation of possible metastatic spread to the lymphatic system in gynaecological cancer. The final result has been discussed by a group of distinguished experts from the EANM Oncology Committee and the European Society of Gynaecological Oncology (ESGO). The document has been endorsed by the SNMMI Board.

Lymphatic mapping and sentinel lymph node biopsy in women with squamous cell carcinoma of the vulva: a gynecologic oncology group study

PURPOSE

To determine the safety of sentinel lymph node biopsy as a replacement for inguinal femoral lymphadenectomy in selected women with vulvar cancer.

PATIENTS AND METHODS

Eligible women had squamous cell carcinoma, at least 1-mm invasion, and tumor size ≥ 2 cm and ≤ 6 cm. The primary tumor was limited to the vulva, and there were no groin lymph nodes that were clinically suggestive of cancer. All women underwent intraoperative lymphatic mapping, sentinel lymph node biopsy, and inguinal femoral lymphadenectomy. Histologic ultra staging of the sentinel lymph node was prescribed.

RESULTS

In all, 452 women underwent the planned procedures, and 418 had at least one sentinel lymph node identified. There were 132 node-positive women, including 11 (8.3%) with false-negative nodes. Twenty-three percent of the true-positive patients were detected by immunohistochemical analysis of the sentinel lymph node. The sensitivity was 91.7% (90% lower confidence bound, 86.7%) and the false-negative predictive value (1-negative predictive value) was 3.7% (90% upper confidence bound, 6.1%). In women with tumor less than 4 cm, the false-negative predictive value was 2.0% (90% upper confidence bound, 4.5%).

CONCLUSION

Sentinel lymph node biopsy is a reasonable alternative to inguinal femoral lymphadenectomy in selected women with squamous cell carcinoma of the vulva.

Reliability of sentinel node assay in vulvar cancer: the first Croatian validation trial

OBJECTIVE

To evaluate the reliability of sentinel node assay in early stage vulvar cancer patients by using preoperative lymphoscintigraphy.

METHODS

Technetium-99m colloid albumin was injected intradermally around the tumor for lymphoscintigraphic mapping and intraoperative hand-held gamma probe detection of sentinel nodes. For all patients, sentinel node biopsy was followed by inguinofemoral lymphadenectomy, regardless of the sentinel lymph node status.

RESULTS

From December 2008 until May 2011, 25 consecutive patients with T1 or T2 stage of vulvar squamous cell cancer were enrolled. The median age of patients was 69 years (range, 48-79). The detection of sentinel lymph node was successful in all 25 patients. A total of 36 sentinel lymph nodes were harvested and metastatic carcinoma was identified in 12 sentinel nodes from 8 patients. There was 1 patient with metastatic non-sentinel lymph node despite the negative sentinel node. Two patients with negative sentinel nodes proven by routine histopathological examination were positive by immunohistochemical staining. The sensitivity, specificity and negative predictive value of sentinel node assay with immunohistochemistry included were 89%, 100%, and 94%, respectively.

CONCLUSIONS

Lymphoscintigraphy and sentinel lymph node biopsy under gamma-detecting probe guidance proved to be an easy and reliable method for the detection of sentinel node in early vulvar cancer. Immunohistochemical analysis improves the sensitivity for the detection of regional micrometastases. The sentinel node assay is highly accurate in predicting the status of the remaining inguinofemoral lymph nodes. Our results indicate that patients best suited to SLN assay have had a simple punch biopsy to confirm the diagnosis rather than a previous tumor excision. This technique represents a true advance in the selection of patients for less radical surgery.

Detection and credibility of sentinel node in vulvar cancer: a single institutional study and short review of literature

PURPOSE

To evaluate the detectability and credibility of sentinel lymph node (SLN) in vulvar cancer.

METHODS

With Tc99m-nanocolloid and methylene blue, we identified SLNs in 34 patients. In 27 cases both tracers were used, while in 7 only blue dye was used. Completion lymphadenectomy was performed in all patients. SLNs and non-SLNs were sent separately for pathologic evaluation.

RESULTS

At least one SLN was identified in all patients. Detection rate per groin was not significantly higher in the combined versus blue dye only technique (42/50 vs. 10/14, p = 0.43). 99m-Tc was not superior to blue dye in detecting SLN (42/50 vs. 50/64, p = 0.65). Midline location of the tumor did not seem to negatively affect the procedure. Four false negatives were observed in three patients with tumors >4 cm. Negative predictive value of SLN was 100% for grade I tumors ≤ 4 cm in patients ≤ 71 years.

CONCLUSION

Tc-99m does not seem to be superior to methylene blue in the detection of SLN in vulvar cancer. Patients of younger age with small, well-differentiated tumors appear to be the most suitable candidates for lymphatic mapping.

A comprehensive overview of radioguided surgery using gamma detection probe technology

The concept of radioguided surgery, which was first developed some 60 years ago, involves the use of a radiation detection probe system for the intraoperative detection of radionuclides. The use of gamma detection probe technology in radioguided surgery has tremendously expanded and has evolved into what is now considered an established discipline within the practice of surgery, revolutionizing the surgical management of many malignancies, including breast cancer, melanoma, and colorectal cancer, as well as the surgical management of parathyroid disease. The impact of radioguided surgery on the surgical management of cancer patients includes providing vital and real-time information to the surgeon regarding the location and extent of disease, as well as regarding the assessment of surgical resection margins. Additionally, it has allowed the surgeon to minimize the surgical invasiveness of many diagnostic and therapeutic procedures, while still maintaining maximum benefit to the cancer patient. In the current review, we have attempted to comprehensively evaluate the history, technical aspects, and clinical applications of radioguided surgery using gamma detection probe technology.

Lymphatic mapping and sentinel node biopsy in gynecological cancers: a critical review of the literature

Although it does not have a long history of sentinel node evaluation (SLN) in female genital system cancers, there is a growing number of promising study results, despite the presence of some aspects that need to be considered and developed. It has been most commonly used in vulvar and uterine cervivcal cancer in gynecological oncology. According to these studies, almost all of which are prospective, particularly in cases where Technetium-labeled nanocolloid is used, sentinel node detection rate sensitivity and specificity has been reported to be 100%, except for a few cases. In the studies on cervical cancer, sentinel node detection rates have been reported around 80–86%, a little lower than those in vulva cancer, and negative predictive value has been reported about 99%. It is relatively new in endometrial cancer, where its detection rate varies between 50 and 80%. Studies about vulvar melanoma and vaginal cancers are generally case reports. Although it has not been supported with multicenter randomized and controlled studies including larger case series, study results reported by various centers around the world are harmonious and mutually supportive particularly in vulva cancer, and cervix cancer. Even though it does not seem possible to replace the traditional approaches in these two cancers, it is still a serious alternative for the future. We believe that it is important to increase and support the studies that will strengthen the weaknesses of the method, among which there are detection of micrometastases and increasing detection rates, and render it usable in routine clinical practice.

Carcinoma of the vulva

The objective of this review is to summarize the published data about squamous carcinoma of the vulva and to identify promising areas for future investigation. Rather than the routine use of complete radical vulvectomy, a radical wide excision of the vulvar lesion to achieve at least a 1-cm gross margin appears sufficient to treat the primary lesion. A surgical assessment of the groin is required for all patients who have invasion greater than 1 mm. Ipsilateral groin node dissection can be performed through a separate incision. All the nodal tissue medial to the vessels and above the fascia should be removed. Sentinel node evaluation may be a significant step forward, but the false-negative rate is not well enough defined to consider this a standard. Patients with positive inguinal nodes at groin dissection should receive radiation therapy to the ipsilateral groin and hemipelvis. For those patients who have unresectable primary disease or if nodes are palpably suspicious, fixed, and/or ulcerated preoperatively, chemoradiation is the preferred option. Exenterative procedures may rarely be required. Chemotherapy for recurrent or metastatic disease has not been proven to be of value. Although survival rates are high for those with negative nodes, the morbidity associated with standard radical techniques has prompted innovation. Adequately powered trials aimed at further reducing morbidity without compromising survival are underway.

Comparison of recurrence after vulvectomy and lymphadenectomy with and without sentinel node biopsy in early stage vulvar cancer

OBJECTIVES

To determine the usefulness of sentinel lymph node biopsy in early stage vulvar cancer and to assess recurrences after surgical treatment with sentinel node identification or surgical treatment without sentinel node identification.

METHODS

We reviewed the records of 55 patients with early stage vulvar cancer operated on between 1995 and 2005. A prospective series of 28 patients who underwent vulvectomy and lymphadenectomy with intraoperative sentinel lymph node identification between 2000 and 2005 (SLN group) was compared with a retrospective series of 27 patients who underwent vulvectomy and lymphadenectomy without sentinel node procedure between 1995 and 2000 (non-SLN group). Patients in the sentinel node identification group underwent preoperative lymphoscintigraphy (technetium-99 colloid albumin injection around the tumor) and intraoperative mapping with isosulfan blue dye.

RESULTS

In the SLN group, 9 tumors were T1 and 19 were T2, with a total of 40 groins dissected and 9 positive nodes in 7 patients. Sixty-two sentinel lymph nodes were detected with a mean of 2.2 sentinel nodes per patient (range 0-4). A false negative case was found. In the non-SLN group, 7 tumors were T1 and 20 were T2, with a total of 49 groins dissected and 9 positive nodes in 6 patients. Recurrence occurred in 8 patients (28.6%) in the SLN group and in 6 (26.9%) in the non-SLN group (P=0.8).

CONCLUSIONS

Sentinel lymph node identification in early stage vulvar cancer is a feasible. Analysis of recurrence may allow considering this procedure as a possible alternative to inguino-femoral lymphadenectomy.

Sentinel Lymph Node Biopsy in Cutaneous Squamous Cell Carcinoma: A Systematic Review of the English Literature

BACKGROUND

Although most cutaneous squamous cell carcinoma (SCC) is curable by a variety of treatment modalities, a small subset of tumors recur, metastasize, and result in death. Although risk factors for metastasis have been described, there are little data available on appropriate workup and staging of patients with high-risk SCC.

OBJECTIVE

We reviewed reported cases and case series of SCC in which sentinel lymph node biopsy (SLNB) was performed to determine whether further research is warranted in developing SLNB as a staging tool for patients with high-risk SCC.

METHODS

The English medical literature was reviewed for reports of SLNB in patients with cutaneous SCC. Data from anogenital and nonanogenital cases were collected and analyzed separately. The percentage of cases with a positive sentinel lymph node (SLN) was calculated. False negative and nondetection rates were tabulated. Rates of local recurrence, nodal and distant metastasis, and disease-specific death were reported.

RESULTS

A total of 607 patients with anogenital SCC and 85 patients with nonanogenital SCC were included in the analysis. A SLN could not be identified in 3% of anogenital and 4% of nonanogenital cases. SLNB was positive in 24% of anogenital and 21% of nonanogenital patients. False-negative rates as determined by completion lymphadenectomy were 4% (8/213) and 5% (1/20), respectively. Most false-negative results were reported in studies from 2000 or earlier in which the combination of radioisotope and blue dye was not used in the SLN localization process. Complications were reported rarely and were limited to hematoma, seroma, cutaneous lymphatic fistula, wound infection, and dehiscence.

CONCLUSIONS

Owing to the lack of controlled studies, it is premature to draw conclusions regarding the utility of SLNB in SCC. The available data, however, suggest that SLNB accurately diagnoses subclinical lymph node metastasis with few false-negative results and low morbidity. Controlled studies are needed to demonstrate whether early detection of subclinical nodal metastasis will lead to improved disease-free or overall survival for patients with high-risk SCC.

The sentinel lymph node: Relevance in gynaecological cancers

AIMS

Sentinel lymph node (SLN) detection is widely practiced in the management of patients with malignant melanoma and beast cancer. Large studies on SLN detection and determination of nodal status have led to changes in the surgical management of the regional lymph nodes in these diseases. More recently attention has focused on other solid cancers, including gynaecological cancers.

METHODS

An extensive literature review of published reports on the SLN in gynaecological cancers was undertaken and the reports were categorised according to the level of evidence provided.

RESULTS

Vulva cancer is the most frequently investigated gynaecological cancer with regard to SLN detection because of its anatomical location and easily accessible nodal basin. Although there are no randomised controlled trials, some data suggest SLN detection in vulval cancer may alter clinical practice and reduce the number of groin lymphadenectomies. The lymphatic drainage of the other gynaecological organs is less predictable, the nodal basin less accessible or less well defined, the techniques not standardised and the evidence for the applicability of SLN detection in the management of these cancers is weak.

CONCLUSION

Sentinel lymph node detection in vulval cancer may reduce the need for radical groin lymphadenectomy and thereby reduce morbidity. SLN detection for other gynaecological cancers has little potential to alter clinical practice.

Lymphatic mapping and sentinel node detection in gynecologic malignancies of the lower genital tract

The utility of lymphatic mapping and sentinel lymph node biopsy in malignancies of the female lower genital tract-- vulvar, vaginal, and cervical cancers--is being explored in multiple centers internationally. For patients with these tumors, lymphatic mapping with sentinel lymph node biopsy holds the promise of increasing the identification of microscopically metastatic disease while decreasing the morbidity of complete lymphadenectomy. In this review article we present the published data on mapping techniques and discuss the advantages and pitfalls of these procedures.

A systematic review of the accuracy of diagnostic tests for inguinal lymph node status in vulvar cancer

OBJECTIVE

To determine the accuracy of minimally and non-invasive tests to assess the groin node status in squamous cell vulvar cancer.

METHODS

A systematic review of published research from 1979 to 2004 that compares the results of tests to determine groin node status with histology at inguinofemoral lymphadenectomy was made. Studies included in the review were those that compared the index test to the standard surgical intervention of inguinofemoral lymphadenectomy and allowed the construction of two-by-two tables. From these tables, sensitivity, specificity, and the likelihood ratios (with 95% confidence intervals) were reported and, where feasible, meta-analysis was used to pool results for each test separately. Sentinel node biopsy using technetium-99m-labelled nanocolloid ((99m)Tc) had a pooled sensitivity and negative LR of 97% (91-100 95% CI) and 0.12 (0.053-0.28 95% CI), respectively, and was the most accurate test reviewed.

CONCLUSION

Five diagnostic tests were identified in a total of 29 studies (961 groins). Although the studies were small and the design often poor, this represents the best summary of the data to date. Sentinel node identification using (99m)Tc appeared to be the most promising test for accurately excluding lymph node metastases in squamous cell vulvar cancer and potentially reducing the radicality of surgery. Its efficacy as a tool in reducing the need for radical surgery and associated patient morbidity without reducing survival needs further assessment probably in a randomised control trial.

Lymphatic mapping for gynecologic malignancies

In gynecologic malignancies, regional lymph node status is a major prognostic factor and a decision criterion for adjuvant therapy. This is the basis for lymphadenectomy. The sentinel node (SN) procedure has emerged as an alternative to systematic lymphadenectomy in various cancers, reducing treatment-related morbidity. In melanoma and breast cancer, SN biopsy is the standard procedure for determining nodal stage. Use of the SN procedure is also well established in vulvar cancer. In small series, combined SN detection based on blue dye and radiocolloid was suitable for the evaluation of lymph node status in cervical cancer. Although some investigators have reported the feasibility of the SN procedure in endometrial cancer, further studies and standardization are required before its routine use can be recommended.

The use of sentinel lymph nodes in gynaecological malignancies

PURPOSE OF REVIEW

Lymphatic mapping and sentinel node biopsy represent one of the most revolutionary advances in oncological surgery in recent years. In this review, the current state of sentinel node detection in gynaecological cancers and its use in vulvar and cervical cancer are assessed.

RECENT FINDINGS

Since the recent clinical application of sentinel node biopsy for melanomas and breast cancer, there has been extensive research on the implementation of this technique to most solid neoplasias. Studies on the feasibility of sentinel node biopsy in vulvar cancer have shown that the status of the sentinel node is an accurate predictor of the status of inguinal nodes. The clinical implementation of the procedure requires validation and is under investigation. In the last two years, several pilot studies on the feasibility of lymphatic mapping/sentinel node biopsy in cervical cancer have yielded promising results. There is minimal experience of its use in endometrial cancer. Detailed pathological study of a sentinel node biopsy with ultrastaging and immunohistochemical or polymerase chain reaction analyses can identify lymph node micrometastasis that conventional methods would identify as negative for metastatic disease. The best histopathological procedure for sentinel node biopsy, the clinical significance of micrometastases, and the appropriate management of such micrometastases are currently under investigation.

SUMMARY

Sentinel node biopsy is one of the main research interests in gynaecological oncological surgery. At present there are not enough data to permit modification of current treatment protocols. Large and multi-institutional trials are required in order to define the implementation of sentinel node biopsy in clinical practice with the objective of achieving safer and more conservative surgery.

Pathologic evaluation of inguinal sentinel lymph nodes in vulvar cancer patients: a comparison of immunohistochemical staining versus ultrastaging with hematoxylin and eosin staining

OBJECTIVES

To evaluate the value of immunohistochemical (IHC) staining of inguinal sentinel lymph nodes (SLN) found to be negative for metastatic disease by ultrastaging with hematoxylin and eosin (H&E) staining.

METHODS

An IRB approved study identified 29 patients who had undergone an inguinal sentinel lymph node dissection for squamous cell carcinoma of the vulva. All sentinel lymph nodes found to be negative for metastatic disease based on ultrastaging with H&E staining were reevaluated with pancytokeratin antibody (AE1/AE3) immunohistochemical (IHC) staining to detect micrometastasis.

RESULTS

Twenty-nine patients with squamous cell carcinoma of the vulva underwent an inguinal sentinel node dissection. Nineteen patients had inguinal dissections negative for metastatic disease, 2 patients had bilateral inguinal metastasis, and 8 patients had unilateral inguinal metastasis. A total of 42 groin dissections with SLN biopsies were performed; 12 groins were positive for metastatic disease and 30 were negative based on ultrastaging with eosin and hematoxylin staining. A total of 107 sentinel lymph nodes (2.5 SLN per groin) were obtained, of which 18 SLN contained metastatic disease identified by ultrastaging and staining with H&E. Two SLN contained micrometastasis less than 0.3mm in size and 16 SLN contained metastasis greater than 2mm in size. Eighty-nine SLN found to be negative for metastasis by ultrastaging with H&E staining were also negative for micrometastasis on evaluation with pancytokeratin antibody AE1/AE3 IHC staining.

CONCLUSIONS

The addition of immunohistochemical staining to ultrastaging with H&E staining in the pathologic evaluation of inguinal sentinel lymph nodes does not increase the detection of micrometastasis in patients with primary squamous cell carcinoma of the vulva.

Sentinel lymphonodectomy in nonmelanoma skin malignancies

BACKGROUND

Whereas the value of sentinel lymphonodectomy (SLNE) in malignant melanoma is established, experience with SLNE in nonmelanoma skin cancers is limited.

OBJECTIVES

The feasibility of SLNE in nonmelanoma skin tumours is evaluated.

METHODS

Thirty-seven patients with high-risk nonmelanoma skin tumours underwent SLNE: 11 squamous cell carcinomas (SCCs), seven Merkel cell carcinomas (MCCs), five cutaneous lymphomas, eight adnexal carcinomas and six other skin cancers, all clinical stage N0.

RESULTS

In nine patients (four MCCs, two SCCs, three lymphomas) the sentinel lymph nodes (SLNs) showed histological evidence of microinvolvement. In five of these nine patients, radical lymph node dissection (RLND) was performed, revealing further micrometastases in three patients (two SCCs, one MCC). No patient with negative SLN showed tumour dissemination during the follow-up over a mean of 2.5 years (range 2 months to 4.5 years, median 2.4 years).

CONCLUSIONS

Our data provide evidence that SLNE is a minimally invasive and highly sensitive staging tool in selected patients with high-risk nonmelanoma skin cancers.

The assessment and surgical management of early-stage vulvar cancer

The treatment of early vulvar cancer has undergone a major paradigm shift from a radical surgical approach to tissue-sparing surgery and preservation of sexual function. Stage I and II tumours represent two-thirds of the cases, and 5-year survival rates reach 80-90%. These tumours, with clinically negative nodes, do not require metastatic work-up, and the patients are submitted to surgery. Stage IA tumours, with a depth of stromal invasion of less than 1 mm, have a very low risk of lymph node (LN) involvement (<1%) and are treated by radical (wide) local excision without the need for lymphadenectomy. The remaining patients with stage I or II disease undergo radical (wide) local excision of the vulvar lesion, accompanied by some sort of inguinal lymphadenectomy. Evaluation of the lymph nodes using sentinel node mapping appears promising and is extensively reviewed. It should probably include serial sectioning and immunohistochemistry to detect micrometastases, although their true clinical importance remains to be determined. Molecular detection methods that reveal cancer cells in sites not detectable by routine histology have been introduced to evaluate sentinel lymph nodes and may eventually become part of the routine metastatic work-up.

Sentinel node identification and the ability to detect metastatic tumor to inguinal lymph nodes in squamous cell cancer of the vulva

OBJECTIVES

The goal of this study was to identify one or more inguinal sentinel nodes in patients with primary squamous cell carcinoma of the vulva and to determine the ability of the sentinel node to predict metastasis to the inguinal lymphatic basin.

METHODS

Techniques employing technetium-99m (Tc-99m) sulfur colloid and isosulfan blue dye were utilized to identify sentinel nodes in the inguinal lymphatic beds. Technetium-99m sulfur colloid was injected intradermally at the tumor margins 90-180 min preoperatively followed by a similar injection of isosulfan blue dye 5-10 min before the groin dissection. A handheld collimated gamma counter was employed to identify Tc-99m-labeled sentinel nodes. Lymphatic tracts that had taken up blue dye and their corresponding sentinel node were also identified and retrieved. A completion inguinal dissection was then performed. Each sentinel node was labeled as hot and blue, hot and nonblue, or cold and blue. The sentinel nodes were subjected to pathologic examination with step sections and nonsentinel nodes were evaluated in the standard fashion.

RESULTS

Twenty-one patients with a median age of 79 were entered onto protocol and a total of 31 inguinal node dissections were performed. A sentinel node was identified in 31/31 (100%) groin dissections with the use of Tc-99m. Isosulfan blue dye identified a sentinel node in 19/31 (61%) groin dissections. Surgical staging revealed 7 patients with stage I disease, 5 with stage II disease, 5 with stage III disease, and 4 with stage IV disease. Lymph nodes in 9 groin dissections were found to have metastatic disease, and in 4 of these dissections, the sentinel node was the only positive node. Lymph nodes in 22 groin dissections had no evidence of metastasis. No false-negative sentinel lymph nodes were obtained (sentinel node negative and a nonsentinel node positive).

CONCLUSION

Tc-99m sulfur colloid is superior to isosulfan blue dye in the detection of sentinel nodes in inguinal dissections of patients with vulvar cancer. A sentinel node dissection utilizing Tc-99m alone can identify a sentinel node in all inguinal dissections. Pathologic examination with step sections has shown the sentinel node to be an accurate predictor of metastatic disease to the inguinal nodal chain.

False-negative sentinel node in patients with vulvar cancer: a case study

Evidence from recent studies indicates that the technique of sentinel node biopsy might be a useful solution for detecting lymph node status for primary vulvar cancer without having to perform radical inguinal lymphadenectomy. The patient in this report underwent sentinel node biopsy, then bilateral inguino-femoral node dissection, and, lastly, radical vulvectomy. The histologic analysis showed a well differentiated squamous cell carcinoma with metastases in one right inguinal node and one left inguinal node and a false-negative right sentinel node. Technically the biopsy of groin sentinel nodes should be quite easy to perform. The use of preoperative lymphoscintigraphy and the intraoperative use of the gamma probe combined with blue dye helps considerably in identifying lymphatic drainage and the sentinel node for vulvar cancer. Further results are needed to confirm the value of sentinel node dissection in the treatment of early stage vulvar cancer.

Further data on the usefulness of sentinel lymph node identification and ultrastaging in vulvar squamous cell carcinoma

OBJECTIVE

The aim was to determine the feasibility of surgical identification and pathological ultrastaging of sentinel nodes (SNs) in vulvar carcinoma and to evaluate whether SN negativity rules out the possibility of metastasis in other nodes and can therefore avoid conventional lymphadenectomy.

MATERIAL AND METHODS

In 26 patients with vulvar squamous cell carcinoma the SNs were detected using both peritumoral injection of (99m)Tc and blue dye (isosulfan or methylene) before the surgical procedure. Dissection of the SNs was followed by standard lymphadenectomy and vulvar exeresis. For pathological ultrastaging at least eight histological sections of every node separated 400 microm were evaluated using hematoxylin & eosin and immunostaining against cytokeratin.

RESULTS

We identified the SNs in 25/26 patients (96%). In 19 patients (76%) the SN was unilateral and in 6 (24%) it was bilateral. A total of 46 SNs were isolated. Metastatic carcinoma was identified in 9 SNs from 8 patients (30.8%). Thirty-eight percent (3 of 8) patients with metastatic SNs presented micrometastasis detected only in ultrastaging. Seven (3.3%) of 239 nonsentinel nodes (non-SNs) showed metastasis. No metastatic implant was detected in non-SNs when SNs were negative in patients without clinical suspicious adenopathy (100% negative predictive value).

CONCLUSION

Inguinofemoral lymph nodes can be confidently avoided when sentinel node metastases are excluded by histological ultrastaging. This may reduce the surgical morbidity of conventional inguinofemoral lymphadenectomy, without worsening vulvar cancer prognosis.