Harbor Occult Metastatic Disease Research Articles

Outcomes of event-free survival in patients with Wilms tumor undergoing preoperative chemotherapy. Analysis of lymph-node yield in a single-center cohort

The clinical value of lymph node sampling in Wilms tumor (WT) lies in its ability to accurately determine lymph node (LN) involvement. LN yield (LNY) is used as a valuable tool to measure LN retrieval, and a minimum of 6 LNs is one of the current recommendations. In patients who are managed with the SIOP strategy, preoperative chemotherapy decreases the retrieval of LN during surgery resulting in lower LNY values. To determine the mean LNY and to analyze survival outcomes in patients with WT who underwent preoperative chemotherapy at a single center. We performed a retrospective chart review of all patients between 6 months and 12 years of age with unilateral WT who underwent preoperative chemotherapy between 2010 and 2018. Patients with bilateral WT or without preoperative chemotherapy were excluded. Collected data included: demographics, tumor volume, tumor histopathology, number of LNs collected (LNY), presence or absence of tumor in the retrieved LNs, and disease stage according to these results. Kaplan Meier curves were calculated to estimate 5-year event-free survival (EFS) and overall survival (OS). 95 patients with a median follow-up of 25 months were included in the study. A total of 19 patients underwent laparoscopic surgery. Mean LNY for the entire cohort was 3.26 (95% CI, 2.4-3.6; SD, 3.62). Six patients (6.3%) had at least one positive LN. The estimated 5-year OS was 89.3% (95% CI, 82.1%-96.5%). EFS was 79.8 (95% CI, 74.8%-84.8%). Recurrence rate was 20% (n: 19). Four patients (4.2%) developed local recurrence and 15 patients (15.7%) developed pulmonary recurrence. The initial mean LNY in patients that relapsed was 4.16 (95% CI, 2.2-5.8; SD: 4.18), which was higher than in patients who did not relapse (LNY: 3; 95% CI, 2.33-3.67; SD, 3.39). No recurrences or deaths occurred in the laparoscopic group. The identification of a minimum LNY (i.e. threshold) to minimize the risk of harboring occult metastatic disease has been proposed to standardize the surgical procedure. Preliminary results in this study suggest that a limited LNY with acceptable survival outcomes is a possible scenario in patients treated according to the SIOP protocol. Systematic LN sampling to reduce the rate of false negatives is still strongly recommended. Our cohort presented with a relatively low LNY compared to standard recommendations. Our EFS, however, remained acceptable. Multivariate analysis would be necessary to determine the actual role of LN sampling as an isolated prognostic factor in unilateral WT.

How many lymph nodes are enough? Assessing the adequacy of lymph node yield for staging in favorable histology wilms tumor

PurposeCurrent investigational priorities in the treatment of favorable histology Wilms tumor (FHWT) center on accurate staging and risk-stratification. The extent of lymph node (LN) sampling has not been clearly defined; its importance cannot be overstated as it guides adjuvant therapy. The identification of a minimum LN yield to minimize the risk of harboring occult metastatic disease could help development of surgical guidelines. This study focuses on using the beta-binomial distribution to estimate the risk of occult metastatic disease in patients with FHWT. Materials & methodsThe National Cancer Database was queried for patients with unilateral FHWT from 2004 to 2013. Data were used to characterize nodal positivity for patients who underwent surgery and had ≥1 positive LN and ≥2 LNs examined. The probability of missing a positive LN (i.e., false negative) for a given LN yield was calculated using an empirical estimation and the beta-binomial model. Patients were then stratified by tumor size. Results422 patients met study criteria. To limit the chance of missing a positive LN to ≤10%, the empirical estimation and beta-binomial model estimated that 6 and 10 LNs needed to be sampled, respectively. Tumor size did not influence the result. Internal validation showed little variation to maintain a false negative rate ≤ 10%. ConclusionsUsing mathematical modeling, it appears that the desired LN yield in FHWT to reduce the risk of false-negative LN sampling to ≤10% is between 6 and 10. The current analysis represents an objective attempt to determine the desired surgical approach to LN sampling to accurately stage patients with FHWT. Level of evidenceII

Pathologic Risk Factors for Metastatic Disease in Postpubertal Patients With Clinical Stage I Testicular Stromal Tumors

To systematically review the existing literature to analyze the impact of previously identified pathologic risk factors on harboring occult metastatic disease (OMD) in patients with Clinical Stage I testicular stromal tumors (TSTs). A literature search using PubMed was conducted using the following terms: "testicular stromal tumors," "testicular Leydig cell tumors," "testicular Sertoli tumors," "testicular interstitial tumors," "testicular granulosa tumor," and "testicular sex cord tumors." For analysis, we included only studies with data on available recurrence, survival, and time-to-event. We hypothesized that patients with ≥2 risk factors would experience lower 5-year OMD-free survival (OMDFS) than those with <2 risk factors. Two hundred ninety-two patients from 47 publications were included with a median age at diagnosis of 35years (range 12-76). Five-year OMDFS and overall survival in patients with Stage I TSTs were 91.2% and 93.2%, respectively. When comparing those who harbored OMD to those who did not, we observed an increased risk of OMD for each additional risk factor (P < .001). Five-year OMDFS was 98.1% for those with <2 risk factors vs 44.9% for those with ≥2 risk factors (P < .001). The existing literature on pathologic risk factors for OMD in this population is insufficient to make broad clinical recommendations. However, these factors appear to risk-stratify patients and may be useful for future research investigating adjuvant therapy in higher-risk patients. This review indicates that such a stratification system has a rational basis.

Abstract C19: The role of resident liver macrophages in suppressing the progression of hepatic micrometastases from pancreatic ductal adenocarcinoma

Abstract Background: The majority of patients with localized pancreatic ductal adenocarcinoma (PDAC) die from metastatic disease, typically of the liver, despite a margin-negative (R0) resection. Therefore, these patients likely harbor occult metastatic disease in the liver at the time of surgery. In this study, we evaluated the role of resident liver macrophages in suppressing the progression of hepatic micrometastases using a murine model of micrometastatic PDAC with patient-derived xenografts (PDXs). Methods and Results: Low-passage, patient-derived KRAS-mutant tumor cells expressing firefly luciferase were injected into the spleens of athymic nude mice resulting in liver metastases, followed by splenectomy to remove the primary tumor. Hepatic tumor burden and metastatic growth kinetics were evaluated by bioluminescent imaging on post-injection days 1, 2, 3, 7, and weekly thereafter. Each of the PDX tumors exhibited a decline in tumor burden over the initial days after injection followed by a period of quiescence with a reproducible, PDX-specific time to proliferative outgrowth ranging from 15 days to greater than 200 days. To assess the role of apoptosis in initial tumor cell clearance and suppression of outgrowth, mouse liver preparations were analyzed for expression of cleaved caspase-3 and cleaved PARP in tumor cells using flow cytometry. There was low expression of both apoptosis markers, suggesting that apoptosis is not a major cell-clearance mechanism. Athymic nude mice lack cell-mediated immunity but have functioning innate immunity. Because there is a large population of resident macrophages in the liver, we hypothesized that macrophages play an important role in the clearance and suppression of hepatic PDAC metastases. To test this, hepatic metastasis outgrowth was assessed following macrophage ablation with liposomal clodronate treatment of mice 48 hours prior to tumor cell injection. Following macrophage ablation, there was a trend toward less robust initial tumor cell clearance and a significantly decreased time to proliferative outgrowth compared with control (13 days vs 26 days, p=0.039). H&amp;E sections demonstrated an abundance of hepatic macrophages surrounding tumor cells in the control group while this response was absent in the clodronate group. Splenic tumor cell injections were repeated using athymic nude mice vs NOD scid gamma (NSG) mice which lack both cell-mediated immunity as well as functional macrophages, dendritic cells, and NK cells. Initial tumor cell clearance was significantly reduced in the NSG mice vs nude mice (PDX 608: 35.6% vs 90.1% clearance at seven days, p&amp;lt;0.001; PDX 366: 40.4% vs 76.3% clearance at seven days, p=0.024). Average relative hepatic bioluminescence at 21 days was significantly increased for PDX 608 in the NSG mice (14.7 vs 0.355, p=0.014) and there was a trend toward increase for PDX 366 (3.07 vs 0.025, p=0.065). Conclusions: In a preclinical model of hepatic micrometastatic PDAC, resident liver macrophages are implicated in the initial clearance and the suppression of proliferation of tumor cells. Further investigation of the interaction of resident hepatic macrophages and micrometastatic PDAC cells may lead to novel strategies for therapy. Citation Format: Alex D. Michaels, Timothy E. Newhook, James M. Lindberg, Sara J. Adair, Sarbajeet Nagdas, Matthew G. Mullen, Edward B. Stelow, J. Thomas Parsons, Todd W. Bauer. The role of resident liver macrophages in suppressing the progression of hepatic micrometastases from pancreatic ductal adenocarcinoma. [abstract]. In: Proceedings of the AACR Special Conference: Function of Tumor Microenvironment in Cancer Progression; 2016 Jan 7–10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2016;76(15 Suppl):Abstract nr C19.

Neoadjuvant Treatment of High-Risk, Clinically Localized Prostate Cancer Prior to Radical Prostatectomy.

Multimodal strategies combining local and systemic therapy offer the greatest chance of cure for many with men with high-risk prostate cancer who may harbor occult metastatic disease. However, no systemic therapy combined with radical prostatectomy has proven beneficial. This was in part due to a lack of effective systemic agents; however, there have been several advancements in the metastatic and castrate-resistant prostate cancer that might prove beneficial if given earlier in the natural history of the disease. For example, novel hormonal agents have recently been approved for castration-resistant prostate cancer with some early phase II neoadjuvant showing promise. Additionally, combination therapy with docetaxel-based chemohormonal has demonstrated a profound survival benefit in metastatic hormone-naïve patients and might have a role in eliminating pre-existing ADT-resistant tumor cells in the neoadjuvant setting. The Cancer and Leukemia Group B (CALGB)/Alliance 90203 trial has finished accrual and should answer the question as to whether neoadjuvant docetaxel-based chemohormonal therapy provides an advantage over prostatectomy alone. There are also several promising targeted agents and immunotherapies under investigation in phase I/II trials with the potential to provide benefit in the neoadjuvant setting.

Risk Stratification of Pubertal Children and Postpubertal Adolescents with Clinical Stage I Testicular Nonseminomatous Germ Cell Tumors

The COG (Children's Oncology Group) currently recommends surveillance for all children and adolescents with clinical stage I testicular germ cell tumors. However, up to 30% of adults with clinical stage I testicular germ cell tumors harbor occult metastatic disease. In adults with clinical stage I nonseminoma some groups advocate a risk stratified approach. Occult metastases were noted in 50% of patients with features such as lymphovascular invasion or embryonal carcinoma predominance in the orchiectomy. However, to our knowledge there are no data on the impact of high risk features in such pubertal children and postpubertal adolescents. We reviewed an institutional testis cancer database for pubertal children and postpubertal adolescents younger than 21 years. We tested the hypothesis that lymphovascular invasion, or 40% or greater embryonal carcinoma in the orchiectomy specimen, would increase the risk of occult metastases, ie relapse during surveillance or positive nodes on retroperitoneal lymph node dissection. We identified 23 patients with a median age of 18.6 years (range 7.1 to 20.9) at diagnosis. Of these patients 14 (60.9%) were on surveillance, 9 (39.1%) underwent primary retroperitoneal lymph node dissection and none received initial chemotherapy. Seven patients (30.4%) had occult metastatic disease. High risk pathological features were found in the orchiectomy specimen in 12 patients (52.2%), including all 12 (52.2%) with 40% or greater embryonal carcinoma and 3 (13.0%) with lymphovascular invasion. Seven patients (58.3%) with high risk features had occult metastatic disease vs none (0%) without high risk features (log rank p = 0.031). Approximately half of pubertal children and postpubertal adolescents with high risk clinical stage I testicular germ cell tumors harbor occult metastatic disease. These results may be useful when discussing prognosis and treatment with patients and families.

Prediction of relapse in stage I nonseminomatous germ cell tumors (NSGCT) by CXCL12: Results from the MRC TE08 and TE22 clinical trials.

319 Background: Stage I NSGCT harbor occult metastatic disease in up to 50% of patients and undergo surveillance with chemotherapy at relapse or adjuvant treatment with excellent survival but concern around subsequent toxicity. Better prediction of relapse would minimize exposure to unnecessary treatments. Previous data suggested CXCL12 aided assessment of relapse risk (Gilbert DC, et al. J Pathol. 2009 Jan;217:94-102). MRC TE08 (Rustin GJ, et al. J Clin Oncol. 2007 Apr 10;25:1310-1315) and TE22 (Huddart RA, et al. J Clin Oncol. 2007 Jul 20;25:3090-3095) were clinical trials incorporating surveillance in stage I NSGCT. Methods: Tumor samples from patients enrolled in TE08 and TE22 were obtained with ethical approval and subjected to immunohistochemical staining for CXCL12. These were scored and CXCL12 analysed as a prognostic factor for relapse independently of vascular invasion (VI - the only currently validated marker). Results: Samples were obtained from 182/466 eligible patients. The 2-year relapse-free rate (RFR) was 76.4%. In CXCL12 moderate/strong cases this was 80.1% (95% CI 73.4-86.8). In CXCL12 absent/weak cases (&lt;1% cells staining moderately or strongly) this was 64.9% (49.6-80.2); hazard ratio 0.54 (95% CI 0.28-1.04). CXCL12 intensity was independently prognostic, p=0.006 (logrank test stratified by VI). Absent/weak CXCL12 expression was significantly associated with embryonal histology (p=0.001). In multivariate analysis including clinical and pathological features, only CXCL12 (HR 0.43, 95%CI 0.22-0.83) and VI (HR 4.77, 95%CI 2.49-9.13) were predictive of relapse. Conclusions: CXCL12 intensity is prognostic for relapse independently of VI. This additional prognostic information can identify groups at very low and very high risk of relapse with potential clinical utility. Acknowledgements: Supported by MRC Biomarkers Grant G0801477 and the NCRI Testis Cancer Clinical Studies Group. [Table: see text]

Neck Dissection for T1 Oral Tongue SCCA: The UCLA Experience

Objective: The study was carried out in order to 1) evaluate features that could identify patients having increased risks of regional recurrences, and 2) examine the prognostic and therapeutic implications of elective neck dissection among patients who presented with early-stage oral tongue squamous cell carcinoma with clinically negative neck (T1cN0). Method: A retrospective chart review of oral tongue cancer at a single tertiary institution identified 123 patients with T1cN0 oral tongue squamous cell carcinoma who underwent surgical tumor extirpation with/without adjuvant radiation treatment and/or chemotherapy from 1990 through 2009. This database was used to identify characteristics that are associated with occult lymph node metastases and measurement of patient outcomes. Results: Eighty-nine patients underwent elective neck dissection, of which 20 patient specimens (22%) were found to harbor occult metastatic disease. However, no significant differences were noted in the frequency of regional recurrence according to gender, age, tumor size, the presence of perineural invasion, or occult metastatic disease ( P = .70, .29, .54, .30, and .47, respectively). In addition, patients who underwent elective neck dissection experienced lower rate of regional recurrence, although this did not achieve a statistically significant level ( P = .52). Conclusion: Clinical observation of the clinically negative neck is justifiable for early stage T1 oral tongue squamous cell carcinoma. Elective cervical lymphadenectomy offers no benefit in preventing regional recurrence when compared to clinical observation. Furthermore, neither patient factors nor intrinsic tumor features demonstrated any prognostic significance in the setting of early stage T1 oral tongue carcinoma.

Margin Clearance and Outcome in Resected Pancreatic Cancer

Current adjuvant therapies for pancreatic cancer (PC) are inconsistently used and only modestly effective. Because a high proportion of patients who undergo resection for PC likely harbor occult metastatic disease, any adjuvant trials assessing therapies such as radiotherapy directed at locoregional disease are significantly underpowered. Stratification based on the probability (and volume) of residual locoregional disease could play an important role in the design of future clinical trials assessing adjuvant radiotherapy. We assessed the relationships between margin involvement, the proximity to operative resection margins and outcome in a cohort of 365 patients who underwent operative resection for PC. Microscopic involvement of a resection margin by tumor was associated with a poor prognosis. Stratifying the minimum clearance of resection margins by 0.5-mm increments demonstrated that although median survival was no different to clear margins based on these definitions, it was not until the resection margin was clear by more than 1.5 mm that optimal long-term survival was achieved. These data demonstrate that a margin clearance of more than 1.5 mm is important for long-term survival in a subgroup of patients. More aggressive therapeutic approaches that target locoregional disease such as radiotherapy may be beneficial in patients with close surgical margins. Stratification of patients for entry onto future clinical trials based on this criterion may identify those patients who benefit from adjuvant radiotherapy.

Stage I Testicular Cancer Management and Necessity for Surgical Expertise

The treatment of patients with testicular germ cell tumors (GCT) has evolved significantly over the past 30 years, primarily because cisplatin-based chemotherapy plus adjunctive surgery cures advanced, metastatic tumors. Treatment of localized and regional disease has also been influenced by the availability of effective systemic therapy. The multiplicity of available treatment approaches has resulted in management controversies, including the optimal treatment of clinical stage I nonseminomatous germ cell tumor (NSGCT). Nerve-sparing retroperitoneal lymph node dissection (RPLND), adjuvant chemotherapy with two cycles of bleomycin, etoposide, and cisplatin (BEP 2), or surveillance have all achieved long-term survival in nearly 100% of patients with clinical stage I NSGCT. Treatment recommendations are frequently governed by patientand tumor-specific factors, such as lymphovascular invasion (LVI). Patients with T1 tumors (organ confined, lacking LVI) have an approximately 15% to 20% chance of relapse after orchiectomy. For these patients, active surveillance with appropriate therapy at relapse (often full-course chemotherapy) at relapse is the preferred option. Management with active surveillance assumes that the patient meets defined criteria, including compliance for follow-up. In contrast, patients with T2 stage I NSGCT (usually associated with LVI) have an approximately 50% chance of harboring occult metastatic disease. In the United States, nerve-sparing RPLND is the preferred option for patients with T2-4 stage I tumors, as well as for those with T1 tumors who are not compliant for rigorous follow-up or who choose NSRPLND over active surveillance. A third, more recent, treatment option has been studied in patients with T2 tumors. BEP 2 is associated with relapse-free survival in more than 95% of instances. This approach was developed in response to the possibility of systemic disease and relapse after RPLND, and to address the lack of experienced urologists outside of specialized centers. The experience reported with this approach has involved patients with high-risk stage I (T2-4; mostly organ-confined tumors with LVI [T2]) because these patients have a 50% probability of harboring regional or distant metastases. The main disadvantage to this approach is the exposure of all patients to the acute and longterm toxicities associated with cisplatin-based combination chemotherapy. Late consequences of chemotherapy are now well recognized, and the spectrum broadens as long-term follow-up of GCT patients who received cisplatin-based chemotherapy increases. Regardless of the approach, it is imperative that the chosen strategy adheres to established follow-up protocols, proven surgical techniques, and standard chemotherapy programs. In the United States, guidelines have been established by the National Comprehensive Cancer Network. In this issue, Albers et al report the results of a phase III multiinstitutional study that compared one cycle of BEP to a unilateral RPLND in an unselected group of patients with clinical stage I NSGCT, nearly 60% of whom had T1 tumors. Three issues need to be considered: stage of disease at treatment, unilateral RPLND, and one cycle of BEP. With 60% of patients having T1 disease, it could be anticipated that approximately 80% of these patients would be cured by orchiectomy alone. Furthermore, among the 40% with greater than T1 disease, six patients in the RPLND arm had pathologic stage IIB disease and one had IIC disease. It is unlikely that that one cycle of BEP would achieve a significant cure rate in these high-volume, clinically understaged tumors. In addition, among studies reporting the results of BEP 2, identification of relapse after chemotherapy would include those occurring as a consequence of chemotherapy resistant, persistent disease in the retroperitoneum, such as growing teratoma and slow-growing NSGCT tumors. Because many relapses from these tumors would be expected at a later time, they have not yet been realized in this study with relatively short follow-up. Thus, the patient population with a high likelihood of cure from orchiectomy alone (than with T1 disease) and the relatively short follow-up likely affected the comparison of one cycle of BEP to surgery. The use of one cycle of BEP remains investigational for patients with clinical stage I NSGCT; if chemotherapy only is chosen as the treatment option, BEP 2 for T2 disease remains the standard regimen. Thirty-two patients (18%) in the RPLND arm of the Albers et al study had tumor-positive nodes (pN1-25; pN2-6, pN3-1) found at RPLND, and all received BEP 2 postoperatively, twice as much chemotherapy as their unresected, randomly assigned counterparts in the one cycle of BEP arm. Given the high proportion of locoregional failures in RPLND node negative–patients who did not receive chemotherapy, additional relapses would likely have occurred in the pathologic stage II patients had they not received BEP 2 adjuvant chemotherapy. Hence, the chemotherapy comparisons are not equivalent. JOURNAL OF CLINICAL ONCOLOGY E D I T O R I A L VOLUME 26 NUMBER 18 JUNE 2

A Phase II Prospective Multi-institutional Trial of Adjuvant Active Specific Immunotherapy Following Curative Resection of Colorectal Cancer Hepatic Metastases: Cancer and Leukemia Group B Study 89903

Patients with curatively resected colorectal cancer hepatic metastases often harbor occult metastatic disease and are at high risk of experiencing recurrence. This patient cohort is ideally suited to test novel therapies such as immunotherapy. We treated patients-post-hepatic resection-with anti-idiotype monoclonal antibody vaccines to the tumor-associated antigens carcinoembryonic antigen (CeaVac) and human milk fat globule (TriAb), both of which are co-expressed in more than 90% of colorectal cancer patients. Vaccinations commenced 6-12 weeks post-hepatic resection and consisted of four biweekly treatments of 2 mg CeaVac and TriAb, then monthly treatments for 2 years, then on every other month for 3 years. The primary endpoint was to investigate the proportion of patients recurrence-free at 2 years, and the objective of the study was to demonstrate that at least 58% would be recurrence-free at this time to consider the regimen worthy of further study. Between July 2001 and October 2004, 56 patients were accrued; 52 patients with margin-negative resection were eligible for analysis. Hepatic lobectomy was performed in 56% of patients with a median of one metastasis (range 1-3). Of the 52 eligible patients, 49 were evaluable for the primary end point. Median follow-up was 3.1 years. The proportion of patients recurrence-free at 2 years was 39%, with a lower confidence bound (LCB) of 0.29. Median recurrence-free survival was 16 months. The 2-year overall survival was 94% (95% CI, 0.81, 0.98). Only 10% of patients had documented grade-3 adverse events. Anti-idiotype monoclonal antibody vaccine therapy with CeaVac and TriAb as an adjuvant to curative resection of colorectal cancer hepatic metastases is well tolerated but did not improve 2-year recurrence-free survival when compared with the expected value of 40% reported for hepatic resection alone.

Indirect MR lymphangiography of the head and neck using conventional gadolinium contrast: A pilot study in humans

To evaluate indirect magnetic resonance lymphangiography (MR-LAG) using interstitial injection of conventional gadolinium contrast (gadoteridol and gadopentetate dimeglumine) for delineating the primary lymphatic drainage of head-and-neck sites. We performed head-and-neck MR-LAG in 5 healthy volunteers, with injection of dermal and mucosal sites. We evaluated the safety of the procedure, the patterns of enhancement categorized by injection site and nodal level, the time course of enhancement, the optimal concentration and volume of contrast, and the optimal imaging sequence. The worst side effects of interstitial contrast injection were brief, mild pain and swelling at the injected sites that were self-limited. MR-LAG resulted in consistent visualization of the primary lymphatic drainage pattern specific to each injected site, which was reproducible on repeated examinations. The best enhancement was obtained with injection of small volumes (0.3-0.5 mL) of either agent diluted, imaging within 5-15 min of injection, and a three-dimensional fast spoiled gradient echo sequence with magnetization transfer. We found head-and-neck MR-LAG to be a safe, convenient imaging method that provides functional information about the lymphatic drainage of injected sites. Applied to head-and-neck cancer, it has the potential to identify sites at highest risk of occult metastatic spread for radiotherapy or surgical planning, and possibly to visualize micrometastases.

The Risk of In-Transit Melanoma Metastasis Depends on Tumor Biology and Not the Surgical Approach to Regional Lymph Nodes

Although the majority of patients newly diagnosed with cutaneous melanoma present with clinically negative regional nodal basins, many of these patients harbor occult regional lymph node metastases. Historically, the initial treatment strategy for patients with clinically negative regional lymph nodes has been controversial. Treatments have included elective dissection, the goal of which was improved survival, and observation followed by dissection when clinical relapse developed. A more rational selective approach, involving lymphatic mapping and sentinel lymph node biopsy (SLNB), has now been widely adopted. SLNB is a minimally invasive technique for identifying the approximately 20% of patients who harbor occult metastatic disease and who may therefore benefit from comple

Laparoscopy and peritoneal cytology in the staging of pancreatic cancer.

Staging laparoscopy in patients with pancreatic cancer allows identification of metastatic disease which is beyond the resolution of computed tomography. Laparoscopic ultrasound, dissection, and/or peritoneal cytology may be used to enhance the sensitivity of the staging procedure. Our experience at Massachusetts General Hospital with staging laparoscopy and peritoneal cytology over the past 8 years (N = 239) reveals that approximately 30% of patients without metastases by computed tomography harbor occult metastatic disease at laparoscopy. Additionally, published series demonstrate accurate determination of resectability in greater than 75% of patients after staging laparoscopy. Staging laparoscopy in patients with pancreatic cancer allows optimization of resources and avoidance of unnecessary surgery.

Modified radical neck dissection: Terminology, technique, and indications

The terminology relating to the various modifications of radical neck dissection is loose and confusing. A simple system of nomenclature has been suggested which allows specification of the node levels dissected and the structures preserved. A technique of modified neck dissection, which excludes dissection of the posterior triangle and spares the sternocleidomastoid muscle and spinal accessory nerve, has been described. We believe this operation is appropriate when local disease is advanced and clinically uninvolved neck nodes are likely to harbor occult metastatic disease, when resection of the primary tumor is through the neck, or when clinical disease in the neck is minimal. Patients with multiple palpable nodes, patients with nodes larger than 3 cm in diameter, patients with disease in the posterior triangle, and patients in whom radiotherapy to the neck has failed may be better served by radical neck dissection.