Sentinel nodes in gynecologic malignancies

Sentinel lymph node biopsy in gynecological malignancies: A modern approach to surgical staging - A narrative review

Sentinel lymph node biopsy (SLNB) has emerged as a valuable alternative to traditional lymphadenectomy in the surgical management of gynecological cancers. This narrative review delves into the advantages, practical applications, and future research directions of SLNB in this context. Compared to the more extensive lymphadenectomy, SLNB offers a minimally invasive approach to lymph node staging, leading to reduced surgical morbidity, faster recovery times, and improved quality of life for the patients involved. This narrative review highlights the high detection rates and accuracy of SLNB in predicting lymph node metastasis, particularly in early-stage endometrial, cervical and vulvar cancers. By accurately assessing lymph node status, SLNB provides crucial information for treatment planning, potentially guiding decisions regarding adjuvant therapies and assessing the need for further lymph node dissection. From clinical practice guidelines, prospective studies, and relevant research articles, this review provides a thorough understanding the evolving role of SLNB in managing gynecological malignancies. The findings presented underscore the potential of SLNB to improve patient outcomes by providing accurate staging while minimizing surgical complications.

Preliminary Study of Sentinel Node Identification with 99mTc Colloid and Blue Dye in Patients with Endometrial Cancer

Aims and Background

Intraoperative lymphatic mapping and sentinel node (SLN) biopsy have generated a tremendous amount of interest and are already established as part of the standard practice in the surgical management of breast cancer and melanoma. To reduce extensive radical procedures and decrease the morbidity in the treatment of gynecologic malignancies, much effort is being made to use less aggressive interventions. The purpose of our study was to determine the feasibility of SLN mapping in a group of patients with endometrial cancer at early stages.

Method and study design

Between September 2000 and May 2001 11 patients with endometrial cancer FIGO stage Ib (n = 10) and Ha (n = 1) underwent laparoscopic SLN detection during laparoscopy-assisted vaginal hysterectomy with bilateral salpingo-oophorectomy and bilateral systematic pelvic lymphadenectomy. Radioactive isotope injection was performed 24 hours before surgery and blue dye injection was performed just before surgery in the cervix at 3, 6, 9 and 12 hours. A 350 mm laparoscopic gamma scintyprobe MR 100 type 11, 99mTc settled (Pol Hi Tech), was used intraoperatively for SLN detection.

Results

Seventeen (17) SLNs were detected with lymphoscintigraphy (six bilateral and five unilateral). At laparoscopic surgery we found the same locations belonging at internal iliac lymph nodes (the so-called Lebeuf-Godard area, lateral to the inferior vesical artery, ventral to the origin of the uterine artery and medial or caudal to the external iliac vein). Fourteen (14) SLNs were negative on histological analysis and three were positive for micrometastases (mean SLN sections = 60). All other pelvic lymph nodes were negative at histological analysis. The same SLN locations detected with the gamma scintyprobe were observed at laparoscopy after patent blue dye injection.

Conclusions

Our preliminary data suggest that combined 99mTc-labeled colloid and vital blue-dye techniques are feasible for SLN detection in endometrial cancer; they represent a very promising tool to transform the management of early-stage endometrial cancer. The clinical validity of this combined technique should be evaluated prospectively.

Contrast-enhanced sonography for detection of secondary lymph nodes in a melanoma tumor animal model

OBJECTIVES

To investigate the use of contrast-enhanced ultrasound imaging (US) for detection of secondary lymph nodes (LNs) in a naturally occurring melanoma swine model compared to surgery and pathologic assessment.

METHODS

Twenty-seven Sinclair swine were studied. The perfluorobutane microbubble contrast agent Sonazoid (GE Healthcare, Oslo, Norway) was administered (1.0 mL total dose) around the melanoma, and contrast-enhanced US was used to localize contrast-enhanced sentinel lymph nodes (SLNs). Then Sonazoid (dose, 0.25-1.0 mL) was injected into the SLNs to detect contrast-enhanced efferent lymphatic channels and secondary LNs. After peritumoral injection of blue dye, a surgeon (blinded to the contrast-enhanced US results) performed a radical LN dissection. Contrast-enhanced US was used to guide removal of any enhanced secondary LNs left after radical LN dissection. Clustered conditional logistic regression analyzed the benefit of contrast-enhanced US-directed secondary LN dissection over radical LN dissection using pathologic findings as the reference standard.

RESULTS

A total of 268 secondary LNs were resected, with 59 (22%) containing metastases. Contrast-enhanced US detected 92 secondary LNs; 248 were identified by radical LN dissection; and 68 were identified by both methods. Metastases were detected in 20% (51 of 248) and 40% (37 of 92) of the secondary LNs identified by radical LN dissection and contrast-enhanced US, respectively. Thus, secondary LNs detected by contrast-enhanced US were nearly 5 times more likely to contain metastases than secondary LNs removed by radical LN dissection (odds ratio, 4.8; P < .0001). Twenty-two of the 180 secondary LNs (12%) identified only by radical LN dissection contained metastases, whereas contrast-enhanced US identified 20 secondary LNs after the surgeon completed the radical LN dissection, of which 8 (40%) contained metastases.

CONCLUSIONS

Secondary LNs can be detected by using contrast-enhanced US after injection of Sonazoid into SLNs. Secondary LNs detected with contrast-enhanced US are significantly more likely to contain metastases than those removed by radical LN dissection.

Lower extremity glandography (LEG): a new concept to identify and enhance lymphatic preservation

BACKGROUND

Lower extremity edema remains a major postoperative complication after inguinal lymphadenectomy for vulvar cancer. This study documents the lymphatic drainage of the vulva versus the lymphatic drainage of the lower extremity coming through the femoral triangle.

METHODS

Seven patients underwent either unilateral or bilateral inguinal lymphadenectomy in conjunction with a radical vulvar resection. Preoperatively, patients had technetium-99 injected into the vulvar cancer. Isosulfan blue was injected into the medioanterior thigh 10 cm below the inguinal ligament. The femoral triangle was opened, and a neoprobe was used to locate the "hot" node bearing the technetium-99. Gentle dissection located the blue lymphatic channel and any blue lymph nodes. The blue and hot nodes were resected and submitted separately. The patients then underwent a complete inguinal lymphadenectomy.

RESULTS

A total of 11 groin dissections were performed. In 9 of the 11 groins, the hot node was identified, and in 8 of the 11 groins, blue node or lymphatic channel was identified. The hot nodes were uniformly located on the superior medial aspect of the femoral triangle. The blue nodes were uniformly located on the lateral aspect of the femoral triangle just anterior to the femoral artery or vein. Three patients had hot lymph nodes containing cancer. Of those 3 patients, one had an additional node positive. None of the blue lymph nodes contained cancer.

CONCLUSIONS

This procedure demonstrates the alternative lymphatic drainage of the leg versus the vulva. Larger studies are necessary to document the exclusivity of these 2 drainage systems. Preservation of the lymphatic drainage of the leg may result in decreased lymphedema.

Mucosal melanomas: a case-based review of the literature

Mucosal melanoma is a rare cancer that is clearly distinct from its cutaneous counterpart in biology, clinical course, and prognosis. Recent studies have shown important differences in the frequencies of various genetic alterations in different subtypes of melanoma. Activating mutations in the c-KIT gene are detected in a significant number of patients with mucosal melanoma. This observation has resulted in the initiation of several clinical trials aimed at exploring the role of receptor tyrosine kinases that inhibit c-KIT in this patient population. We herein present a comprehensive literature review of mucosal melanoma along with case vignettes of a number of pertinent cases. We further discuss melanomas of the head and neck, the female genital tract, and the anorectum, which are the three most common sites of mucosal melanoma, with a particular focus on the diagnostic, prognostic, and therapeutic data available in the literature.

Sentinel node identification in cervical cancer patients undergoing transperitoneal radical hysterectomy: a study of 100 cases

We investigated the feasibility of sentinel lymph node (SN) identification using radioisotopic lymphatic mapping with technetium-99m-labeled nanocolloid and blue-dye injection in 100 patients with early cervical cancer (FIGO stage IB1 in 58, IB2 in 18, and IIA in 24) undergoing radical hysterectomy with pelvic lymphadenectomy. At least one SN was found in 84% on one side and in 66% on both sides. The sentinel detection rates according to the stages were as follows: 96.6% in IB1, 66.7% in IB2, and 62.5% in IIA with at least one SN on one side, and 86.2% in IB1, 38.9% in IB2, and 37.5% in IIA with at least one SN on both sides. Successful identification of at least one SN was less likely in patients with tumors >2 cm (54% of SN) compared with those with tumors </=2 cm (96% of SN). In 15/22 patients, the SNs were the only lymph nodes that were tumor positive. The false-negative rate for the SN procedure was 3% (3/100). In all false-negative SNs, the primary cervical tumor was above 2 cm and there was an isthmus infiltration. SN detection had 86.4% sensitivity (19/22), 100% specificity (66/66), and 95.5% negative predictive value (63/68). The sentinel node detection rate is relatively high and depends on the tumor size and FIGO stage.

Frozen section: Its role in gynaecological oncology

The use of frozen section has greatly impacted on the care of the gynaecological oncology patient. Frozen section allows intraoperative evaluation to distinguish benign from malignant tumors in order to tailor the extent of surgery necessary. Frozen section diagnosis in gynaecological oncology is sufficiently sensitive and specific for clinical use. Generally, the false negative rate is low and the false positive rate is negligible. Deferred diagnoses or incompatible frozen section diagnosis is usually due to technical limitations especially for the mucinous ovarian tumors. This review summarises the available literature on the accuracy, limitations and role of frozen section for individual gynaecological tumors.

What is the most appropriate scan timing for intraoperative detection of malignancy using 18F-FDG-sensitive gamma probe? Preliminary phantom and preoperative patient study

PURPOSE

To evaluate the appropriate post-injection timing for hand-held-gamma-ray-detecting probe (GDP) scanning for the intraoperative detection of malignancy after preoperative F-18 FDG (FDG) injection.

METHODS

Patient study with superficially located cancer was performed on three patients before operation by dual-phase whole-body PET at 2 and 6-7 hr post-injection of FDG (370 MBq), and by probe scanning from the skin at several points at 1, 3, 5, and 7 hr after FDG injection. TNRa (tumor-adjacent-normal ratio) and TNRc (tumor-contralateral-normal ratio) were calculated. Phantom study was also performed to determine basic GDP function.

RESULTS

The patient study revealed that tumors showed constant TNRa (0.9-1.3) and TNRc (1.1-3.0) by GDP count rate, and that there was no tendency of an increase in TNRa with time. The standard deviations of GDP count rate were lower at 1-3 hr post-injection compared with those of delayed scans. While delayed PET showed an increase or no change in the tumor FDG uptake, the decrease of normal tissue FDG uptake was not adequate to create higher TNRs. The phantom study revealed that LN model showed TNRa of 1.7 or greater by GDP count rate (cps) when background contained no FDG, but that they showed TNRa of 1.3 or less when the background contained 4% of the LN FDG activity per ml.

CONCLUSION

The present study suggests that higher FDG count rate of tumors at 1-3 hr postinjection would be more suitable for the gamma-probe detection compared with lower count rate at 6-7 hr delayed scans with wide standard deviations.

Lymphatic sparing, laparoscopic varicocelectomy: a new surgical technique

Several surgical options are available for managing varicoceles. Although conventional surgery offers good surgical results, the most common long-term complication of surgery is the development of hydroceles, thought to be due to interruption in the lymphatic outflow from the subservient testis. The authors describe a new technique of in vivo methylene blue mapping of testicular lymphatic vessels at laparoscopy, allowing these vessels to be spared during laparoscopic varicocelectomy. This novel method of in vivo staining of lymphatic vessels should prevent damage to the lymphatic system and avoid the late development of hydroceles. A prospective multicenter trial is currently underway to evaluate the medium- and long-term results.

Vulvar melanoma: a report of 20 cases and review of the literature

BACKGROUND

Vulvar melanoma is the second most common vulvar malignancy and represents a significant women's health issue.

OBJECTIVE

To report experience with 21 cases of vulvar melanoma in 20 patients and to review the literature about the condition.

METHODS

Parameters retrospectively reviewed included age at diagnosis, family history of melanoma, location on the vulva, atypical nevi, Breslow depth, ulceration status, histologic pattern, presenting signs and symptoms, and the results of sentinel lymph node biopsy. Molecular characterization of the melanocortin type 1 receptor was performed in 1 patient.

RESULTS

A family history of cutaneous melanoma was present in 15% of cases. The mean Breslow depth was 2.8 mm (range, 0.0-11.0 mm). Ten patients successfully underwent sentinel lymph node biopsy, results of which were positive in 2 (20%). Reported for the first time is that one patient had a germline mutation in the melanocortin type 1 receptor.

CONCLUSION

Vulvar and cutaneous melanoma behave similarly despite their unique pathogeneses. Sentinel lymph node biopsy can be performed successfully for vulvar melanoma.

Vulvar Melanoma: Review of Diagnosis, Staging, and Therapy

OBJECTIVES

To update, assimilate, and bridge the contemporary literature on vulvar and cutaneous melanoma regarding diagnosis, staging, and therapy to provide a useful clinical reference for managing and counseling for affected patients.

MATERIALS AND METHODS

A computerized search for reports in the literature up to June 2003 was carried out using PubMed and MEDLINE databases. Multidisciplinary involvement was used in evaluating the available data and formulating conclusions.

RESULTS

More than 300 reports were reviewed. Diagnosis, staging, and therapy aspects of vulvar melanoma are summarized.

CONCLUSIONS

Vulvar melanoma represents a subtype of cutaneous melanoma, with similar prognostic and staging factors. The most recent American Joint Committee on Cancer staging system for cutaneous melanoma is applicable to vulvar melanoma. Sentinel lymph node biopsy is reliable for staging the regional lymph node basin for vulvar melanoma. Standardized documentation of clinical and histopathologic parameters is needed to standardize grouping of cases for future comparison studies.

Pre-operative lymphatic mapping and intra-operative sentinel lymph node detection in early stage endometrial cancer

Lymphatic mapping and sentinel lymph node (SLN) biopsy are becoming increasingly useful for the identification of tumour lymphatic spread in a wide variety of neoplasms, such as breast cancer and melanoma, reducing unnecessary radical lymph node resection. The aim of our study was to determine the feasibility of lymphatic mapping with both labelled colloid and patent blue violet in patients with early stage endometrial cancer. Sixteen consecutive patients with endometrial cancer, stage International Federation of Gynecology and Obstetrics (FIGO Ib), were included in the study. Lymphoscintigraphy and laparoscopically assisted intra-operative SLN detection were performed in all patients. In addition, to verify the prognostic role of this method, 12 of 16 patients were followed up for a period of at least 1 year. In 15 of 16 patients, 24 SLNs (all internal iliac lymph nodes) were detected at lymphoscintigraphy (six monolateral and nine bilateral). At histological analysis, three of the 24 were positive for micrometastases, whereas the remaining 21 were negative. No other surgically dissected lymph nodes presented metastases. At 1 year of follow-up, none of the 12 patients presented relapse of their disease. In conclusion, in endometrial cancer, both pre-operative lymphoscintigraphy and intra-operative gamma-probe detection of SLNs represent promising tools for the visualization of SLNs. The status of the latter may yield a correct representation of pelvic lymph node involvement, providing important information for further treatment.

Aetiology and prevalence of lower limb lymphoedema following treatment for gynaecological cancer

OBJECTIVE

To determine the prevalence and incidence of lower limb lymphoedema (LLL) in a cohort of women who had treatment for gynaecological cancer between May 1995 and April 2000.

DESIGN

A retrospective survey.

SETTING

The study took place at an urban referral centre in an Australian tertiary referral women's hospital.

SAMPLE

The data collection was based on 66% of 743 women on the database of the Gynaecological Cancer Centre.

METHODS

Interviews and assessments were conducted to determine the status of lower limbs; medical records were reviewed for age, weight, site and type of cancer and treatment.

MAIN OUTCOME MEASURES

Leg swelling, diagnosed lower limb lymphoedema, no swelling of the legs and type of surgery were determined as the main outcome measures.

RESULTS AND CONCLUSIONS

The diagnosis of lower limb lymphoedema was made in 18% of the total sample: 53% of these were diagnosed within 3 months of treatment, a further 18% within 6 months, 13% within 12 months and the remaining 16% up to 5 years following treatment. Women most at risk for developing LLL were those who had treatment for vulvar cancer with removal of lymph nodes and follow up radiotherapy. For this subsample, the prevalence was 47%. The finding that LLL occurs within the first year is earlier than hitherto generally believed. It is therefore imperative for all health professionals to include care and assessment of the legs particularly during the immediate pre- and postoperative period.

Recent advances in the pathology of the vulva

This review addresses recent and important advances in our knowledge of several uncommon or rare disorders of the vulva including Paget's disease, vulva intraepithelial neoplasia, lichen sclerosus and squamous hyperplasia and their relationship to squamous carcinoma. Emphasis is placed on the two biologically different types of squamous carcinoma related and unrelated to human papillomavirus infection. Finally, the relatively recent concept of the sentinel node as applied to vulva carcinoma is discussed.