Transcriptome-guided resolution of tumor microenvironment interactions in pheochromocytoma and paraganglioma subtypes

BACKGROUND

Pheochromocytomas and paragangliomas (PCPG) are rare catecholamine-secreting endocrine tumors deriving from chromaffin cells of the embryonic neural crest. Although distinct molecular PCPG subtypes have been elucidated, certain characteristics of these tumors have yet to be fully examined, namely the tumor microenvironment (TME). To further understand tumor-stromal interactions in PCPG subtypes, the present study deconvoluted bulk tumor gene expression to examine ligand-receptor interactions.

METHODS

RNA-sequencing data primary solid PCPG tumors were derived from The Cancer Genome Atlas (TCGA). Tumor purity was estimated using two robust algorithms. The tumor purity estimates and bulk tumor expression values allowed for non-negative linear regression to predict the average expression of each gene in the stromal and tumor compartments for each PCPG molecular subtype. The predicted expression values were then used in conjunction with a previously curated ligand-receptor database and scoring system to evaluate top ligand-receptor interactions.

RESULTS

Across all PCPG subtypes compared to normal samples, tumor-to-tumor signaling between bone morphogenic proteins 7 (BMP7) and 15 (BMP15) and cognate receptors ACVR2B and BMPR1B was increased. In addition, tumor-to-stroma signaling was enriched for interactions between predicted tumor-originating delta-like ligand 3 (DLL3) and predicted stromal NOTCH receptors. Stroma-to-tumor signaling was enriched for interactions between ephrins A1 and A4 with ephrin receptors EphA5, EphA7, and EphA8. Pseudohypoxia subtype tumors displayed increased predicted stromal expression of genes related to immune-exhausted T-cell response, including those for inhibitory receptors HAVCR2 and CTLA4.

CONCLUSION

The current exploratory study predicted stromal and tumor through compartmental deconvolution and yielded previously unrecognized interactions and putative biomarkers in PCPG.

What to do When Decompressive Gastrostomies and Jejunostomies are not Options? A Scoping Review of Transesophageal Gastrostomy Tubes for Advanced Malignancies

BACKGROUND

In advanced malignant bowel obstruction, decompressive gastrostomy tubes (GTs) may not be feasible due to ascites, peritoneal carcinomatosis, and altered gastric anatomy. Whereas nasogastric tubes (NGTs) allow temporary decompression, percutaneous transesophageal gastrostomy tubes (PTEGs) are an alternative method for long-term palliative decompression. This study performed a scoping review to determine outcomes with PTEG in advanced malignancies.

METHODS

A systematic literature search was performed to include all studies that reported the clinical results of PTEGs for malignancy. No language, national, or publication status restrictions were used.

RESULTS

The analysis included 14 relevant studies with a total of 340 patients. In 11 studies, standard PTEGs were inserted with a rupture-free balloon's placement into the mouth or nose and esophageal puncture under fluoroscopy or ultrasound, followed by a guidewire into the stomach with placement of a single-lumen tube. Of 340 patients, 65 (19.1%) had minor complications, and 5 (2.1%) had significant complications, including bleeding and severe aspiration pneumonia. Of 171 patients, 169 with PTEGs (98.8%) reported relief of nasal discomfort from NGT and alleviation of obstructive symptoms. The one randomized controlled trial reported a significantly higher quality of life with PTEGs than with NGTs.

CONCLUSIONS

When decompression for advanced malignancy is technically not feasible with a gastrostomy tube, the PTEG is a viable, safe option for palliation. The PTEG is associated with lower significant complication rates than the gastrostomy tube and significantly higher patient-derived outcomes than the NGT.

Cost-Benefit Analysis of Robotic vs. Laparoscopic Hepatectomy: A Propensity-Matched Retrospective Cohort Study of American College of Surgeons National Surgical Quality Improvement Program Database

BACKGROUND

Robotic and laparoscopic hepatectomies having increased utilization as minimally invasive techniques are explored for hepatobiliary malignancies. Although the data on outcomes from these 2 approaches are emerging, the cost-benefit analysis of these approaches remains sparse. This study compares the costs associated with robotic vs. laparoscopic liver resections, taking into account 30-day complications.

METHODS

Using the American College of Surgeons National Surgical Quality Improvement Program database, a propensity-matched cohort of patients with laparoscopic or robotic liver resections between 2014 and 2017 was identified. Costs were assigned to perioperative variables, including operating room (OR) time, length of stay, blood transfusions, and 30-day complications. Cost estimates were obtained from the Centers for Medicare and Medicaid Services billing data (2017), American Hospital Association data (2017), relevant literature, and local institutional cost data.

RESULTS

In our matched cohort of 454 patients (227 per group), total costs associated with laparoscopic liver resections were estimated at $5.5 M ($24 K per patient) vs. $6.8 M ($29.8 K per patient) for robotic liver resections (21.3% difference, P < .001). The higher cost associated with robotic hepatectomies was related to blood transfusions ($22.0 K vs. $12.1 K, P = .02), length of stay ($2.05 M vs. $1.76 M, P = .046), and OR time ($4.01 M vs. $3.24 M, P < .0001).

DISCUSSION

Robotic hepatectomies were associated with higher costs compared to laparoscopic hepatectomies. The 2 major contributors to the cost disparity were increased OR time and increased length of stay. Future studies are warranted to analyze high-volume Minimally Invasive Surgery surgeons' impact in specialty centers on potentially mitigating this current cost disparity.

Simple Versus Radical Resection for Duodenal Adenocarcinoma: A Propensity Score Matched Analysis of National Cancer Database

BACKGROUND

Duodenal adenocarcinoma treatment consists of either simple or radical surgical resection. Existing evidence suggests similar survival outcomes between the two but is limited by small numbers and single-institution analysis. We aim to compare survival after partial versus radical resection for duodenal adenocarcinoma using the National Cancer Database (NCDB).

METHODS

Using NCDB results from 2004 to 2014, we compared patients with duodenal adenocarcinoma undergoing partial resection (n = 1247) and radical resection (n = 1240) by age, sex, facility type, facility location, cancer stage, cancer grade, lymph node sampling, node status, tumor size, margin status, neoadjuvant therapy, and adjuvant therapy using chi-square analysis. Survival was compared using propensity matching.

RESULTS

Patients undergoing partial resection had overall earlier cancer stage, more favorable tumor grade, and were less likely to undergo lymph node sampling and neoadjuvant therapy. When overall survival was compared between the 2 propensity-matched groups, the median survival was 46.7 months after partial resection and 43.2 months after radical resection (P = .329), and overall survival was similar between the 2 groups (P = .894). The use of adjuvant therapy demonstrated improved survival over either surgery alone (P < .0001, P = .0037).

CONCLUSION

Partial resection did not demonstrate worse survival outcomes than radical resection for duodenal adenocarcinoma. The use of adjuvant therapy in addition to surgery demonstrated improved survival regardless of surgery type and played a larger role in survival than the type of surgery. Our findings provide evidence to support the continued use of both partial and radical surgical resections to treat duodenal malignancy.

Omental patch versus gastric resection for perforated gastric ulcer: Systematic review and meta-analysis for an unresolved debate

BACKGROUND

Perforated gastric ulcers are surgical emergencies with paucity of data on the preferred treatment modality of resection versus omental patch. We aim to compare outcomes with ulcer repair and gastric resection surgeries in perforated gastric ulcers after systematic review of literature.

METHODS

A systematic literature search was performed for publications in PubMed Medline, Embase, and Cochrane Central Register of Controlled Trials. We included all studies which compared ulcer repair vesus gastric resection surgeries for perforated gastric ulcers. We excluded studies which did not separate outcomes gastric and duodenal ulcer perforations.

RESULTS

The search included nine single-institution retrospective reviews comparing ulcer repair (449 patients) versus gastric resection surgeries (212 patients). Meta-analysis was restricted to perforated gastric ulcers and excluded perforated duodenal ulcers. The majority of these studies did not control for baseline characteristics, and surgical strategies were often chosen in a non-randomized manner. All of the studies included were at high risk of bias. The overall odds ratio of mortality in ulcer repair surgery compared to gastric resection surgery was 1.79, with 95% CI 0.72 to 4.43 and p-value 0.209.

CONCLUSION

In this meta-analysis, there was no difference in mortality between the two surgical groups. The overall equivalence of clinical outcomes suggests that gastric resection is a potentially viable alternative to ulcer repair surgery and should not be considered a secondary strategy. We would recommend a multicenter randomized control trial to evaluate the surgical approach that yields superior outcomes.

LEVEL OF EVIDENCE

Systematic review and meta-analysis, level III.

Role of metastasectomy for liver metastasis in stage IV anal cancer

INTRODUCTION

There is a paucity of data on the role of metastasectomy for metastatic anal cancer on survival outcomes. We aim to define the role of metastasectomy in stage IV anal cancer.

METHODS

National Cancer Database (NCDB) from 2004 to 2014 was accessed to include patients with metastatic anal cancer, excluding adenocarcinoma, neuroendocrine, and 'other' histologies. We compared patients undergoing metastasectomy (n = 165) to those who did not have metastasectomy (n = 2093) by age, sex, cancer grade, and site of metastasis, including metastasis to bone, liver, and lung, using chi-square analysis. The primary outcome was overall survival.

RESULTS

Patients had equal distribution of metastatic sites between those who underwent metastasectomy versus no metastasectomy: bone (7.64% vs 4.85%, p = 0.22), brain (0.24% vs 0%, p = 1.0), liver (23.22% vs 29.70%, p = 0.07), and lung (11.85% vs 9.09%, p = 0.38). Survival following metastasectomy was increased at one year (71% vs. 61%, p = 0.016), two years (50% vs. 38%, p = 0.014), and five years (30% vs. 19%, p = 0.025). Median overall survival was increased (23 months vs. 16 months; p = 0.015) for patients with metastasectomy. Survival increases were demonstrated only in the group with liver metastasis undergoing metastasectomy. When stratifying for liver metastases only, median overall survival time was further increased (34 months vs. 16 months; p < 0.0001) following metastasectomy.

CONCLUSION

These results demonstrate a survival benefit for hepatic metastasectomy in stage IV anal cancer. Our findings demonstrate a potential survival benefit in highly select patients with metastatic anal cancer to the liver. These findings support further investigation in a randomized clinical trial to delineate these findings.

Implications for the use of telehealth in surgical patients during the COVID-19 pandemic

•Telehealth has become a medical necessity during the COVID-19 pandemic. •Surgeons must integrate this new technology into surgical practice. •Effective for detecting post-operative complications and preoperative counseling.

Primary Malignancy Is an Independent Determinant of Morbidity and Mortality after Liver Resection

Although outcomes after liver resection have improved, there remains considerable perioperative morbidity and mortality with these procedures. Studies suggest a primary liver cancer diagnosis is associated with poorer outcomes, but the extent to which this is attributable to a higher degree of hepatic dysfunction is unclear. To better delineate this, we performed a matched pair analysis of primary versus metastatic malignancies using a national database. The American College of Surgeons National Surgical Quality Improvement Program (2005-2013) was analyzed to select elective liver resections. Diagnoses were sorted as follows: 1) primary liver cancers and 2) metastatic neoplasms. A literature review identified factors known to impact hepatectomy outcomes; these variables were evaluated by a univariate analysis. The most predictive factors were used to create similar groups from each diagnosis category via propensity matching. Multivariate regression was used to validate results in the wider study population. Outcomes were compared using chi-squared test and Fisher exact test. Matched groups of 4838 patients were similar by all variables, including indicators of liver function. A number of major complications were significantly more prevalent with a primary diagnosis; overall major morbidity rates in the metastatic and primary groups were 29.3 versus 41.6 per cent, respectively. The mortality rate for primary neoplasms was 4.6 per cent (vs 1.6%); this represents a risk of death nearly three-times greater (95% confidence interval = 2.20-3.81, P < 0.0001) in cancers of hepatic origin. Hepatectomy carries substantially higher perioperative risk when performed for primary liver cancers, independent of hepatic function and resection extent. This knowledge will help to improve treatment planning, patient education, and resource allocation in oncologic liver resection.

Primary Malignancy is an Independent Determinant of Morbidity and Mortality after Liver Resection

Although outcomes after liver resection have improved, there remains considerable perioperative morbidity and mortality with these procedures. Studies suggest a primary liver cancer diagnosis is associated with poorer outcomes, but the extent to which this is attributable to a higher degree of hepatic dysfunction is unclear. To better delineate this, we performed a matched pair analysis of primary versus metastatic malignancies using a national database. The American College of Surgeons National Surgical Quality Improvement Program (2005–2013) was analyzed to select elective liver resections. Diagnoses were sorted as follows: 1) primary liver cancers and 2) metastatic neoplasms. A literature review identified factors known to impact hepatectomy outcomes; these variables were evaluated by a univariate analysis. The most predictive factors were used to create similar groups from each diagnosis category via propensity matching. Multivariate regression was used to validate results in the wider study population. Outcomes were compared using chi-squared test and Fisher exact test. Matched groups of 4838 patients were similar by all variables, including indicators of liver function. A number of major complications were significantly more prevalent with a primary diagnosis; overall major morbidity rates in the metastatic and primary groups were 29.3 versus 41.6 per cent, respectively. The mortality rate for primary neoplasms was 4.6 per cent (vs 1.6%); this represents a risk of death nearly three-times greater (95% confidence interval = 2.20–3.81, P < 0.0001) in cancers of hepatic origin. Hepatectomy carries substantially higher perioperative risk when performed for primary liver cancers, independent of hepatic function and resection extent. This knowledge will help to improve treatment planning, patient education, and resource allocation in oncologic liver resection.

Bullous pemphigoid associated with a lymphoepithelial cyst of the pancreas

Bullous pemphigoid (BP) is an acquired, autoimmune, subepidermal blistering disorder. A possible paraneoplastic association has been suggested; however, debate remains regarding the precise relationship of these neoplasms with BP. We present a case of recalcitrant BP in a 67-year-old man with a pancreatic neoplasm that was found to be a lymphoepithelial cyst. Immunoperoxidase staining of the cyst demonstrated C₃d along the basement membrane of the stratified squamous epithelium, suggesting that the BP may have involved the lymphoepithelial cyst itself. Shortly after excision of the cyst, BP rapidly resolved without any immunosuppressive treatment, raising the possibility that the immunologic process involving the lymphoepithelial cyst of the pancreas was the inciting factor for the patient's cutaneous disease. Although rare, some cases of BP may be a paraneoplastic process. A thorough screening via patient history and directed laboratory studies may be warranted in recalcitrant cases.

The utility of the MELD score in predicting mortality following liver resection for metastasis

BACKGROUND

The MELD score has been demonstrated to be predictive of hepatectomy outcomes in mixed patient samples of primary and secondary liver cancers. Because MELD is a measure of hepatic dysfunction, prior conclusions may rely on the high prevalence of cirrhosis observed with primary lesions. This study aims to evaluate MELD score as a predictor of mortality and develop a risk prediction model for patients specifically undergoing hepatic metastasectomy.

METHODS

ACS-NSQIP 2005-2013 was analyzed to select patients who had undergone liver resections for metastases. A receiver operating characteristic (ROC) analysis determined the MELD score most associated with 30-day mortality. A literature review identified variables that impact hepatectomy outcomes. Significant factors were included in a multivariable analysis (MVA). A risk calculator was derived from the final multivariable model.

RESULTS

Among the 14,919 patients assessed, the mortality rate was 2.7%, and the median MELD was 7.3 (range = 34.4). A MELD of 7.24 was identified by ROC (sensitivity = 81%, specificity = 51%, c-statistic = 0.71). Of all patients above this threshold, 4.4% died at 30 days vs. 1.1% in the group ≤7.24. This faction represented 50.1% of the population but accounted for 80.3% of all deaths (p < 0.001). The MVA revealed mortality to be increased 2.6-times (OR = 2.55, 95%CI 1.69-3.84, p < 0.001). A risk calculator was successfully developed and validated.

CONCLUSIONS

MELD>7.24 is an important predictor of death following hepatectomy for metastasis and may prompt a detailed assessment with the provided risk calculator. Attention to MELD in the preoperative setting will improve treatment planning and patient education prior to oncologic liver resection.

Phase II Trial of Paclitaxel/Cisplatin Followed by Surgery and Adjuvant Radiation Therapy and 5-Fluorouracil/Leucovorin for Gastric Cancer (ECOG E7296)

BACKGROUND

Randomized trials have shown an increase in survival with perioperative chemotherapy as well as with postoperative chemoradiation. It was hypothesized that combining induction chemotherapy with postoperative chemoradiation would be well tolerated and improve pathologic complete response.

METHODS

Patients with resectable cancers of the stomach/gastroesophageal junction were eligible. Neoadjuvant chemotherapy consisted of 3 cycles of paclitaxel and cisplatin. Adjuvant therapy consisted of 1 cycle of 5-fluorouracil (FU) and leucovorin (LV) followed by chemoradiation (45 Gy with concurrent 5-FU/LV). Chemoradiation was followed by 2 additional cycles of 5-FU/LV. Response to neoadjuvant therapy was based on pathology.

RESULTS

From 1999 to 2002, 38 eligible patients were enrolled; 35 completed induction chemotherapy, and 29 went on to surgery. Sixteen patients did not develop metastatic progression, 10 developed metastatic disease, and 12 were unevaluable. There were no pathologic complete responses after induction therapy. Twenty-five of 38 patients suffered grade 3-4 toxicities during induction paclitaxel/cisplatin. Six of the 7 patients who received postoperative therapy suffered grade 3-4 toxicities. Only 3 of 38 (7.9%) eligible patients completed all assigned treatment. The median overall survival was 1.6 years, and the 2-year survival was 40%.

CONCLUSIONS

This regimen of neoadjuvant paclitaxel/cisplatin followed by postoperative 5-FU/LV-based chemoradiation did not have a high enough response rate and proved to be too toxic for further development.

Early experience with robotic radiosurgery for local control of liver metastasis

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Background: Liver toxicity limits radiation therapy for liver metastasis; however, robotic radiosurgery delivers effective doses with limited toxicities. Robotic radiosurgery may be an effective treatment for liver metastases in patients with lesions not amenable to surgical resection.

Methods: We conducted a retrospective study of patients treated with robotic radiosurgery for liver metastasis at our institution from June 2008 and June 2010. Medical records were reviewed and all cases discussed in multi-disciplinary conference. Preradiosurgery and follow-up abdominal computed tomography (CT) scans reviewed for treatment response. Our primary endpoint was local recurrence, defined as increased enhancement or tumor progression within the treatment field on follow-up CT scan.

Results: Thirty-three patients had 37 liver metastasis treated with robotic radiosurgery (17 colorectal, 4 ovarian, 4 breast, 3 melanoma, 2 liver, 2 lung, 1 gastric, 1 cholangiocarcinoma, 1 pancreas, 1 anal, 1 bladder). Eighteen of 33 patients (54.5%) had isolated liver metastasis. Prior to radiosurgery 27 of 33 patients (81.8%) had undergone surgical resection of primary tumor, 26 of 33 patients (78.8%) were treated with chemotherapy for metastatic disease, and 15 of 33 patients (45.5%) had non-liver radiation therapy. Median time from primary diagnosis to radiosurgery treatment was 33.3 months (5.7 to 320 months). Patients received median radiation dose of 30 Gy (22.5 to 42) over 3 to 5 fractions. Median follow up was 8.1 months (1.2 to 23.5). There were no cases of liver failure. Sixteen patients had disease progression outside the treatment field (15 liver, 6 systemic) with a median time to progression of 4.6 months (0.9 to 17.6). Five lesions (13.5%) had in field progression with a median time to progression of 10 months (2.6 to 13.1). Seventeen patients (51.5%) died during follow-up.

Conclusions: Robotic radiosurgery offers a potential local therapy for patients with metastatic liver disease with limited toxicity. Longer follow-up and more patients are required to better assess its safety. Robotic radiosurgery may fill a role for patients with lesions not amenable to traditional ablative and surgical techniques.

Time of day is associated with postoperative morbidity: an analysis of the national surgical quality improvement program data

OBJECTIVE

To examine the association between surgical start time and morbidity and mortality for nonemergent procedures.

SUMMARY BACKGROUND DATA

Patients require medical services 24 hours a day. Several studies have demonstrated a difference in outcomes over the course of the day for anesthetic adverse events, death in the ICU, and dialysis care. The relationship between operation start time and patient outcomes is yet undefined.

METHODS

We performed a retrospective cohort study of 144,740 nonemergent general and vascular surgical procedures performed within the VA Medical System 2000-2004 and entered into the National Surgical Quality Improvement Program Database. Operation start time was the independent variable of interest. Logistic regression was used to adjust for patient and procedural characteristics and to determine the association between start time and, in 2 independent models, mortality and morbidity.

RESULTS

Unadjusted later start time was significantly associated with higher surgical morbidity and mortality. After adjustment for patient and procedure characteristics, mortality was not significantly associated with start time. However, after appropriate adjustment, operations starting between 4 pm and 6 pm were associated with an elevated risk of morbidity (OR = 1.25, P < or = 0.005) over those starting between 7 am and 4 pm as were operations starting between 6 pm and 11 pm (OR = 1.60, P < or = 0.005).

CONCLUSIONS

When considering a nonemergent procedure, surgeons must bear in mind that cases that start after routine "business" hours within the VA System may face an elevated risk of complications that warrants further evaluation.

Postoperative mortality after esophagectomy for cancer: development of a preoperative risk prediction model

BACKGROUND

Surgical resection for the treatment of esophageal cancer remains a high-risk procedure. To develop a model to predict risk of postoperative death, we sought to identify factors associated with postoperative mortality for Medicare patients undergoing esophagectomy for cancer.

METHODS

We evaluated patients in the Surveillance, Epidemiology, and End Results Program (SEER)-Medicare database who underwent esophagectomy for esophageal cancer from 1997 to 2003. Variables evaluated were patient age, race, marital status, sex, tumor stage, Charlson score, and hospital volume. Hospital volume was evaluated in tertiles of even volume groups (low, < .67 cases a year; medium, .68 to 2.33 cases a year; high, > 2.33 cases a year). The primary outcome measure was postoperative mortality, defined as death within 30 days of esophagectomy or death during the hospitalization in which the primary surgical procedure was performed. In-hospital deaths more than 30 days after esophagectomy were included in the outcomes to more accurately estimate the true mortality of this procedure. Multivariable logistic regression analyses were performed to evaluate the relationship between patient and provider characteristics and postoperative mortality. Finally, characteristics identified by the regression analysis were used to generate a simplified, clinically applicable model predicting risk of postoperative mortality in the Medicare population.

RESULTS

A total of 1172 patients underwent esophageal cancer surgery during this study period. Overall postoperative mortality was 14%. Multivariable logistic regression demonstrated that age, Charlson score, and hospital volume were statistically significant predictors of postoperative mortality. The other variables such as race, martial status, sex, and disease stage were not found to be significant. The odds of postoperative mortality at low-volume hospitals were almost twice those at a high-volume hospital. Age greater than 80 increased odds of mortality almost twofold. Similarly, Charlson scores of > or = 2 resulted in more than a 1.5-fold risk of postoperative mortality. Our prediction model using these variables accurately stratified postoperative mortality for this population.

CONCLUSIONS

Postoperative mortality (30-day and in-hospital) remains high after esophagectomy. Age, Charlson score, and hospital volume were identified as independent predictors of postoperative mortality. A simple risk prediction model that uses preoperative clinical data accurately predicted patient postoperative mortality for this SEER-Medicare population.

Identification of high-risk patients among those diagnosed with thin cutaneous melanomas

PURPOSE

Most patients with melanoma have microscopically thin (< or = 1 mm) primary lesions and are cured with excision. However, some develop metastatic disease that is often fatal. We evaluated established prognostic factors to develop classification schemes with better discrimination than current American Joint Committee on Cancer (AJCC) staging.

PATIENTS AND METHODS

We studied patients with thin melanomas from the US population-based Surveillance, Epidemiology, and End Results (SEER) cancer registry (1988 to 2001; n = 26,291) and those seen by the University of Pennsylvania's Pigmented Lesion Group (PLG; 1972 to 2001; n = 2,389; Philadelphia, PA). AJCC prognostic factors were thickness, anatomic level, ulceration, site, sex, and age; PLG prognostic factors also included a set of biologically based candidate prognostic factors. Recursive partitioning was used to develop a SEER-based classification tree that was validated using PLG data. Next, a new PLG-based classification tree was developed using the expanded set of prognostic factors.

RESULTS

The SEER-based classification tree identified additional criteria to explain survival heterogeneity among patients with thin, nonulcerated lesions; 10-year survival rates ranged from 89.1% to 99%. The new PLG-based tree identified groups using level, tumor cell mitotic rate, and sex. With survival rates from 83.4% to 100%, it had better discrimination.

CONCLUSION

Prognostication and related clinical decision making in the majority of patients with melanoma can be improved now using the validated, SEER-based classification. Tumor cell mitotic rate should be incorporated into the next iteration of AJCC staging.

HIV protease inhibitor nelfinavir inhibits growth of human melanoma cells by induction of cell cycle arrest

HIV protease inhibitors (HIV PI) are a class of antiretroviral drugs that are designed to target the viral protease. Unexpectedly, this class of drugs is also reported to have antitumor activity. In this study, we have evaluated the in vitro activity of nelfinavir, a HIV PI, against human melanoma cells. Nelfinavir inhibits the growth of melanoma cell lines at low micromolar concentrations that are clinically attainable. Nelfinavir promotes apoptosis and arrests cell cycle at G(1) phase. Cell cycle arrest is attributed to inhibition of cyclin-dependent kinase 2 (CDK2) and concomitant dephosphorylation of retinoblastoma tumor suppressor. We further show that nelfinavir inhibits CDK2 through proteasome-dependent degradation of Cdc25A phosphatase. Our results suggest that nelfinavir is a promising candidate chemotherapeutic agent for advanced melanoma, for which novel and effective therapies are urgently needed.

Targeting HER-2/neu in Early Breast Cancer Development Using Dendritic Cells with Staged Interleukin-12 Burst Secretion

Overexpression of HER-2/neu (c-erbB2) is associated with increased risk of recurrent disease in ductal carcinoma in situ (DCIS) and a poorer prognosis in node-positive breast cancer. We therefore examined the early immunotherapeutic targeting of HER-2/neu in DCIS. Before surgical resection, HER-2/neu(pos) DCIS patients (n = 13) received 4 weekly vaccinations of dendritic cells pulsed with HER-2/neu HLA class I and II peptides. The vaccine dendritic cells were activated in vitro with IFN-gamma and bacterial lipopolysaccharide to become highly polarized DC1-type dendritic cells that secrete high levels of interleukin-12p70 (IL-12p70). Intranodal delivery of dendritic cells supplied both antigenic stimulation and a synchronized preconditioned burst of IL-12p70 production directly to the anatomic site of T-cell sensitization. Before vaccination, many subjects possessed HER-2/neu-HLA-A2 tetramer-staining CD8(pos) T cells that expressed low levels of CD28 and high levels of the inhibitory B7 ligand CTLA-4, but this ratio inverted after vaccination. The vaccinated subjects also showed high rates of peptide-specific sensitization for both IFN-gamma-secreting CD4(pos) (85%) and CD8(pos) (80%) T cells, with recognition of antigenically relevant breast cancer lines, accumulation of T and B lymphocytes in the breast, and induction of complement-dependent, tumor-lytic antibodies. Seven of 11 evaluable patients also showed markedly decreased HER-2/neu expression in surgical tumor specimens, often with measurable decreases in residual DCIS, suggesting an active process of "immunoediting" for HER-2/neu-expressing tumor cells following vaccination. DC1 vaccination strategies may therefore have potential for both the prevention and the treatment of early breast cancer.

Regional Nodal Metastatic Disease Is the Strongest Predictor of Survival in Patients with Thin Vertical Growth Phase Melanomas: A Case for SLN Staging Biopsy in These Patients

BACKGROUND

The benefit of sentinel lymph node (SLN) biopsy for patients with thin (< or =1.0 mm) melanomas, even for prognostic value, is controversial. This may partly result from the relatively small number and short follow-up of SLN-positive patients in this group. Previously, we have shown that clinical regional nodal metastatic disease (RNMD) serves as a good surrogate for SLN positivity. Here, we use RNMD as a validated surrogate for SLN positivity and examine its prognostic value in a large pre-SLN group of patients with thin vertical growth phase (VGP) lesions who would today commonly be offered SLN biopsy in our practice.

METHODS

Between 1972 and 1991, 472 patients with thin VGP melanomas with at least 10 years' follow-up were eligible for the study. Kaplan-Meier survival curves were computed for patients with and without RNMD. A multivariate Cox model and classification tree analysis were used to evaluate clinical and histopathologic predictors of survival.

RESULTS

Sixty-seven patients (14.2%) developed recurrence, 53.7% of whom developed RNMD. Forty-five patients (9.5%) experienced melanoma-related deaths (MRD). The most statistically significant predictor of MRD was RNMD (hazard ratio [HR] 13.5, P < .0001). Thickness (HR 10.5, P = .004), axial location (HR 4.6, P = .001), and age >60 years (HR 2.7, P = .005) additionally were independently associated with an increased risk of MRD. RNMD patients demonstrated a 44.4% 10-year disease-specific mortality.

CONCLUSIONS

RNMD was the most statistically significant factor associated with MRD in patients with thin VGP lesions. This supports the prognostic use of SLN biopsy in this group, recognizing that additional factors, including thickness, axial location, and older age were independently associated with a worse survival outcome.

Predicting sentinel node status in AJCC stage I/II primary cutaneous melanoma

BACKGROUND

Sentinel lymph node (SLN) status is an important prognostic factor for survival for patients with primary cutaneous melanoma. To address the issue of selecting patients at high and low risk for a positive SLN, prognostic factors were sought that predict SLN involvement by examining characteristics of both the primary tumor and the patient within the context of a biological model of melanoma progression.

METHODS

The study included 682 patients with primary vertical growth phase (VGP) melanoma and no clinical evidence of metastatic disease who underwent SLN biopsy (1995-2003). Logistic regression and classification tree analyses were used to investigate the association between SLN positivity and Breslow thickness, Clark level, tumor infiltrating lymphocytes (TIL), ulceration, mitotic rate (MR), lesion site, gender, and age. RESULTS.: In all, 88 of the 682 patients had > or =1 positive SLN (12.9%). In the multivariate analysis, MR, TIL, and thickness were found to be independent prognostic factors for SLN positivity. In the classification tree, four different risk groups were defined, ranging from minimal risk (2.1%) to high risk (40.4%). In lesions < r =2.0 mm, MR was important in risk-stratifying patients, and in lesions >2.0 mm TIL was important.

CONCLUSIONS

By incorporating biologically based variables such as VGP, TIL, and MR along with thickness into a prognostic model, both patients at high risk and minimal risk for SLN positivity can be identified. If validated, this model can be used in patient management and trial design to select patients to undergo or be spared SLN biopsy.

Preferential involvement of CX chemokine receptor 4 and CX chemokine ligand 12 in T-cell migration toward melanoma cells

Our previous analysis of the role of chemokines in T lymphocyte trafficking toward human tumor cells revealed the migration of a melanoma patient's cytotoxic T lymphocytes (CTL) toward autologous tumor cells, resulting in tumor cell apoptosis, in an organotypic melanoma culture. CTL migration was mediated by CX chemokine receptor (CXCR) 4 expressed by the CTL and CX chemokine ligand (CXCL) 12 secreted by the tumor cells, as evidenced by blockage of CTL migration by antibodies to CXCL12 or CXCR4, high concentrations of CXCL12 or small molecule CXCR4 antagonist. Here, we present the results of T cell migration in one additional melanoma patient and T cell and tumor cell analyses for CXCR4 and CXCL12 expression, respectively, in 12 additional melanoma patients, indicating the preferential role of CXCR4 and CXCL12 in CTL migration toward melanoma cells. These studies add to the increasing body of evidence suggesting that CXCL12 is a potent chemoattractant for T cells.

Use of Radiotracer for Sentinel Lymph Node Mapping in Breast Cancer Optimizes Staging Independent of Site of Administration

PURPOSE

In an effort to optimize sentinel lymph node (SLN) mapping for breast cancer, sites of mapping agent administration and types of mapping agents used continue to be evaluated. This study compares SLN mapping using peritumoral (PT) or subareolar (SA) injection of radiolabeled colloid and examines the relative contributions of radiotracer and blue dye to SLN identification.

MATERIALS AND METHODS

A retrospective review was performed of 456 patients with breast cancer and clinically negative axillae who underwent SLN mapping. Sequential groups of patients were injected with filtered Tc-99m SC, 326 peritumorally (group 1) and 130 subareolarly (group 2). All patients had intraoperative SA injection of 1% isosulfan blue dye.

RESULTS

The SLN identification and isotope success rates were 97% and 96% in group 1 and 98% and 98% in group 2, respectively. Eighty-one patients (25%) in group 1 and 44 patients (34%) in group 2 had positive SLNs. Of these patients, 15% from group 1 and 14% from group 2 had only positive nodes detected by radiotracer, and 9 of these patients (6 from group 1 and 3 from group 2) had other nodes identified by both radiotracer and blue dye that were negative for metastases. Six percent of patients with positive SLNs were upstaged because of use of radiotracer.

CONCLUSIONS

PT and SA injection of radiotracer have comparable success rates for axillary SLN identification. Given that 15% of patients in group 1 and 14% in group 2 had only positive SLNs detected by radiotracer, independent of site of administration, radiotracer remains essential for optimizing breast SLN mapping.

Predictors of regional nodal disease in patients with thin melanomas

BACKGROUND

Most melanoma patients present with thin (<or=1.0 mm) lesions. Indications for sentinel lymph node (SLN) biopsy are not well defined for this group. Previously, we reported an association between mitotic rate (MR) and SLN positivity in these patients. The study was limited by a relatively small sample size and low statistical power. In this study, we evaluated a large population of patients with thin melanoma from the pre-SLN era to identify predictors of regional nodal disease (RND) that may serve as a surrogate for SLN positivity.

METHODS

Eight hundred eighty-two patients evaluated between 1972 and 1991 were included in the study. Univariate and multivariate regression analyses were performed by using clinical and histological data to identify factors associated with RND. A multivariate logistic regression model was developed and applied to the previously reported group of patients with thin melanomas who underwent SLN biopsy between 1996 and 2004 for validation.

RESULTS

Thirty-eight patients (4.3%) had evidence of RND. In the multivariate analysis, a MR>0, vertical growth phase (VGP), male sex, and ulceration were statistically significant predictors of RND. Patients at the highest risk according to a classification tree analysis (VGP and MR>0) had an RND rate of 11.9%. The regression model developed predicted well the SLN status in the validation sample.

CONCLUSIONS

Investigation of a large pre-SLN population identified MR>0, ulceration, VGP, and male sex as independently predictive of RND in patients with thin melanomas. These factors may help to identify subgroups of these patients that have clinically significant risks of SLN positivity.

Should all melanoma patients undergo sentinel lymph node biopsy?

PURPOSE OF REVIEW

It is now well established that sentinel lymph node biopsy is a powerful test to predict prognosis for melanoma patients. Controversy exists, however, regarding the appropriate selection of patients for sentinel lymph node biopsy, especially among patients with thin melanomas (< 1 mm Breslow thickness), thick melanomas (> 4 mm Breslow thickness), or locally recurrent melanoma.

RECENT FINDINGS

The majority of the studies in the past 2 years regarding sentinel lymph node biopsy have been concerned with identifying factors that can better predict regional nodal metastasis and survival. Other studies have proposed a better risk stratification model, which includes these factors, to best select those patients at increased risk of nodal positivity.

SUMMARY

Although much research has been done to select appropriate patients for sentinel lymph node biopsy based on multiple prognostic factors, further studies are necessary to completely define the indications for this procedure in patients with thin, thick and locally recurrent melanomas.

AKT activation and response to interferon-beta in human cancer cells

Significant growth inhibition and induction of apoptosis by IFN-beta in cancer cells including colorectal cancer cells have been observed. We and others have previously reported the Stat 1 induction of TRAIL is a crucial step in the IFN-beta induced apoptosis pathway. However, when evaluating the sensitivity of a panel of colorectal cancer cell lines, we found no clear correlation between activation of the Jak/Stat signaling pathway and response to interferon. In the present study, we have evaluated the interaction of the PI3k/Akt pathway and IFN-beta induced apoptosis in human colorectal cancer cells. The results demonstrate a correlation between Akt activity, phosphorylation of Bad and resistance to interferon-induced apoptosis in these cells. The association of activation of Akt, phosphorylation of Bad and resistance to IFN-beta-induced apoptosis was further supported by the observation that disruption of the pathway in a more resistant cell line led to sensitization, and expression of an activated Akt in a more sensitive cell line led to increased resistance. Taken together, this data indicates that the PI3/Akt kinase pathway may be an important contributor to IFN-beta sensitivity and resistance in colorectal cancer cells. This data demonstrates a potential pathway by which cells may develop resistance to IFN, and further elucidation of this process may allow us to better target IFN therapy.

Mitotic rate as a predictor of sentinel lymph node positivity in patients with thin melanomas

BACKGROUND

Lymphatic mapping and sentinel lymphadenectomy (LM/SL) provide important prognostic information for patients with early-stage melanoma. Although the use of this technique in patients with thin melanomas (< or =1.00 mm) is not routine, risk factors that may predict sentinel lymph node (SLN) positivity in this patient population are under investigation. We sought to determine whether mitotic rate (MR) is associated with SLN positivity in thin-melanoma patients and, therefore, whether it may be used to risk-stratify and select patients for LM/SL.

METHODS

Clinical and histopathologic variables were reviewed for 181 patients with thin melanomas who underwent LM/SL from January 1996 through January 2004. Univariate and multivariate logistic regression analyses were performed to identify factors associated with SLN positivity. Risk groups were defined on the basis of the development of a classification tree.

RESULTS

The overall SLN positivity rate was 5%. All patients with positive SLNs had an MR of >0. By univariate analysis, MR and thickness were significant predictors of SLN positivity. The association between MR and SLN positivity remained significant controlling for each of the other variables evaluated. On the basis of a classification tree, patients with an MR >0 and tumor thickness > or =.76 mm were identified as a higher-risk group, with an SLN positivity rate of 12.3%.

CONCLUSIONS

In patients with thin melanomas, MR >0 seems to be a significant predictor of SLN positivity that may be used to risk-stratify and select patients for LM/SL. To confirm these results, the predictive value of MR for SLN positivity needs to be validated in other populations of thin-melanoma patients.

Combined 5-fluorouracil/systemic interferon-beta gene therapy results in long-term survival in mice with established colorectal liver metastases

Preclinical in vitro and in vivo studies have demonstrated synergistic interactions between 5-fluorouracil (5-FU) and type I and II IFNs against human colorectal cancer cells. Despite these activities, randomized human trials have failed to identify a clinical benefit for this combination treatment. These limited clinical results may be secondary to the short half-life of recombinant IFN protein and the increased systemic toxicities of 5-FU/IFN combinations. We have previously reported an adenoviral-mediated IFN-beta gene therapy strategy, which may circumvent the pitfalls of recombinant IFN therapy. However, a dose-dependent toxicity and acute inflammatory response to systemically administered adenovirus vectors may limit the clinical application of this therapy. The combination of adenoviral-mediated IFN-beta gene therapy and 5-FU resulted in tumor regression, apoptosis, and improved survival in an established liver metastases model. These therapeutic effects were observed at a significantly lower vector dose than we had previously reported and with limited toxicity. This approach may allow for an effective clinical application of this therapy and warrants additional investigation.

Gene therapy for cancer and metastatic disease

Gene therapy has been applied to the treatment of cancer and metastatic disease for over ten years. Research in this area has utilised multiple gene therapy approaches including targeting tumour suppressor genes and oncogenes, stimulating the immune system, targeted chemotherapy, antiangiogenic strategies, and direct viral oncolysis. In recent years, gene delivery vectors have been developed that selectively target tumour cells through tumour-specific receptors, deletion of certain viral gene sequences, or incorporation of tumour-specific promoter sequences that drive gene expression. Preclinical models have produced promising results, demonstrating significant tumour regression and reduction of metastatic disease. Unfortunately, only limited responses have been observed in clinical trials. The main limitations in treating metastatic disease include poor vector transduction efficiencies and difficulties in targeting remote tumour cells with systemic vector delivery. Currently, various groups are investigating means to improve gene delivery and clinical responses by continuing to modify gene delivery vectors and by concentrating on combination gene therapy and multimodality therapy.

Stat1-dependent induction of tumor necrosis factor-related apoptosis-inducing ligand and the cell-surface death signaling pathway by interferon beta in human cancer cells

Type I IFNs are known to inhibit tumor cell growth and stimulate the immune system. However, little is known of the mechanism of type I IFN-induced apoptosis in human cancer cells. In this study, we have IFN-beta treatment of a human colorectal cell line (KM12L4) and a resistant clone of this cell line, L4RIFN. We demonstrate the induction of apoptosis in the parent cell line. This process was associated with the induction of the Jak-Stat signaling pathway, induction of the proapoptotic mediator tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), and activation of procaspase-3, -8, -9, and -10. Additionally, we evaluated the role of Stat1 in mediating IFN-beta induction of these proapoptotic signals in a fibrosarcoma cell line (2ftgh) and a Stat1-deficient clone (U3A). Our results demonstrate that IFN-beta induction of apoptosis and the induction of proapoptotic mediator TRAIL is Stat1 dependent. Evaluation of a stable transfectant of the KM12L4 cell line expressing c-FLIP supports the role of TRAIL and the cell-surface death signaling pathways in IFN-beta induction of apoptosis. Studies evaluating the TRAIL promoter indicate induction of TRAIL promoter activity by IFN-beta. These results may represent a novel pathway by which IFN-beta may induce therapeutic effects.

Changes in the surgical management of patients with breast carcinoma based on preoperative magnetic resonance imaging

BACKGROUND

Breast magnetic resonance imaging (MRI) is a developing technique for the evaluation of patients with primary breast carcinoma. The authors assessed the impact of preoperative breast MRI on surgical management.

METHODS

The current study was a retrospective review of 267 patients with primary breast tumors who had MRI studies prior to undergoing definitive surgery.

RESULTS

Two hundred sixty-seven patients with invasive breast carcinoma who had preoperative breast MRI studies and had complete clinical, radiologic, and pathologic data available were identified and formed the basis of this analysis. The overall sensitivity of MRI for detecting primary, intact breast tumors was 95%. Planned surgical management was altered in 69 of 267 patients (26%); and, in 49 of those patients (71%), there was pathologic verification of malignancy in the surgical specimen that confirmed the need for wider or separate excision or mastectomy. Forty-four of 267 patients (16.5%) had conversion of planned breast conservation to mastectomy. In a univariate analysis, change in management was associated significantly with histology; management was altered in 11 of 24 lobular tumors (46%) compared with 58 of 243 ductal tumors (24%; P = 0.02).

CONCLUSIONS

Breast MRI was very sensitive for the detection of primary, intact, invasive breast carcinoma and improved local staging in almost 20% of patients. Preoperative breast MRI studies may be particularly useful in surgical planning for and management of patients with lobular carcinoma.

Intraperitoneal photodynamic therapy causes a capillary-leak syndrome

BACKGROUND

In patients undergoing intraperitoneal (IP) photodynamic therapy (PDT), the combination of aggressive surgical debulking and light therapy causes an apparent systemic capillary-leak syndrome that necessitates significant intensive care unit (ICU) management after surgery.

METHODS

From May 1997 to May 2001, 65 patients underwent surgical debulking and PDT as part of an ongoing phase II trial for disseminated IP cancer. Perioperative data were reviewed retrospectively, and statistical analyses were performed to determine whether any identifiable factors were associated with the need for mechanical ventilation for longer than 1 day and with the occurrence of postoperative complications.

RESULTS

Forty-three women and 22 men (mean age, 49 years) were treated. Operative time averaged 9.8 hours, and mean estimated blood loss was 1450 mL. The mean crystalloid requirement for the first 48 hours after surgery was 29.3 L, and 49 patients required blood products. Twenty-four patients were intubated for longer than 24 hours, with a mean of 8.3 days for those intubated longer than 1 day. The median ICU stay was 4 days. Overall, 110 complications developed in 45 (69%) of the 65 patients. Significant complications included 6 patients with acute respiratory distress syndrome, 28 patients with infectious complications, and 4 patients with anastomotic complications. Statistical analyses revealed that surgery-related factors were significantly associated with these complication outcomes.

CONCLUSIONS

Patients who undergo surgical debulking and IP PDT develop a significant capillary-leak syndrome after surgery that necessitates massive volume resuscitation, careful ICU monitoring, and, frequently, prolonged ventilatory support.

Magnetic resonance imaging-guided biopsy of mammographically and clinically occult breast lesions

BACKGROUND

Breast magnetic resonance imaging (MRI) is a very sensitive technique for detection of breast cancer. We report on MRI-guided needle localization for biopsy of abnormalities seen only on MRI.

METHODS

A retrospective review was performed of 231 patients with invasive breast cancer or ductal carcinoma-in-situ who had MRI as part of their evaluation and treatment at the University of Pennsylvania between 1992 and 1998. Clinical, radiological, and pathologic data were examined.

RESULTS

MRI needle localization was performed in 41 (18%) patients. MRI needle localization was required for a finding of a mammographically or clinically occult lesion in 31 patients, better MRI definition of tumor in 5 patients, and surgeon's choice in 5 patients. In all cases, MRI localization and excisional biopsy were successfully completed. Nineteen of 31 patients were found to have additional mammographically and clinically occult tumors. There were 12 (29%) false-positive MRI scans.

CONCLUSIONS

MRI has a high sensitivity for detection of breast cancer; additional mammographically and clinically occult sites of tumor are detected in approximately 1 (15%) of 7 breast cancer patients. These otherwise occult sites of disease can be appropriately biopsied with MRI needle-localization techniques.

Magnetic resonance imaging-guided biopsy of mammographically and clinically occult breast lesions

BACKGROUND

Breast magnetic resonance imaging (MRI) is a very sensitive technique for detection of breast cancer. We report on MRI-guided needle localization for biopsy of abnormalities seen only on MRI.

METHODS

A retrospective review was performed of 231 patients with invasive breast cancer or ductal carcinoma-in-situ who had MRI as part of their evaluation and treatment at the University of Pennsylvania between 1992 and 1998. Clinical, radiological, and pathologic data were examined.

RESULTS

MRI needle localization was performed in 41 (18%) patients. MRI needle localization was required for a finding of a mammographically or clinically occult lesion in 31 patients, better MRI definition of tumor in 5 patients, and surgeon's choice in 5 patients. In all cases, MRI localization and excisional biopsy were successfully completed. Nineteen of 31 patients were found to have additional mammographically and clinically occult tumors. There were 12 (29%) false-positive MRI scans.

CONCLUSIONS

MRI has a high sensitivity for detection of breast cancer; additional mammographically and clinically occult sites of tumor are detected in approximately 1 (15%) of 7 breast cancer patients. These otherwise occult sites of disease can be appropriately biopsied with MRI needle-localization techniques.

Subareolar and peritumoral injection identify similar sentinel nodes for breast cancer

BACKGROUND

Sentinel lymph node (SLN) mapping with radioisotope and blue dye is rapidly becoming the standard of care for breast cancer. The optimal location for injection of radioisotope and blue dye is still being investigated. The goal of this study was to determine whether blue dye injection into the subareolar (SA) location localized the same sentinel nodes as the peritumoral (PT) location for patients with breast cancer.

METHODS

Three hundred thirty-two patients with biopsy-proven operable breast cancer or ductal carcinoma in situ at two institutions underwent SLN mapping. Eighty-three patients had PT injection of blue dye (group 1), and 249 patients had SA injection of blue dye (group 2). All patients underwent PT injection of (99m)Tc-labeled sulfur colloid.

RESULTS

The two groups were similar in age, previous biopsy type, and tumor size, location, and histology. The mean number of SLNs identified was 2.4 (range, 0-9) in group 1 and 2.5 (range, 0-11) in group 2. The SLN identification rate was 95% for group 1 and 97% for group 2. The isotope success rate was 94% for both groups. The blue dye success rate was 84% for group 1 and 90% for group 2. The isotope/blue dye concordance rate was 87% for group 1 and 90% for group 2. At a median follow-up of 28 months (range, 14 to 40), there were no axillary recurrences in any of the 332 patients.

CONCLUSIONS

These data suggest that delivery of mapping reagents in the SA and PT locations identifies similar lymph nodes. Because of simplicity and the similarity in node identification between SA and PT injection, further investigation of the SA site for delivery of SLN mapping reagents for breast cancer is warranted.

Intra-arterial delivery of a recombinant adenovirus does not increase gene transfer to tumor cells in a rat model of metastatic colorectal carcinoma

Hepatic artery infusion of adenoviral vectors has been shown to increase transduction of certain hepatocellular malignancies in preclinical studies. In addition, clinical trials have begun evaluating the efficacy of gene transfer of cytotoxic genes to metastatic colorectal tumors through hepatic artery infusion. Here we evaluate the extent of gene expression and therapeutic effect following various routes of administration of recombinant adenovirus in a rat model of metastatic colorectal carcinoma. We administered adenovirus (AdCMVlacZ) to rats with established colorectal metastases through infusion into the hepatic artery, intravenous infusion, or direct injection into a tumor. Intravenous administration resulted in transduction of hepatocytes, but not tumor cells. Hepatic arterial administration failed to substantially increase transduction of tumor cells. In addition, ligation of the hepatic artery following infusion of adenovirus or the addition of lipiodol infusion had no effect on the transduction of tumor cells. We administered AdCMVp53 by direct injection into tumors, intravenous administration, or hepatic artery infusion to evaluate the delivery of a therapeutic gene. Direct injection of AdCMVp53 into established hepatic colorectal metastases resulted in a therapeutic response in comparison with both hepatic arterial and intravenous infusion of vector. These preclinical studies fail to support a strategy of infusion through the hepatic artery of recombinant adenovirus targeting tumor cells in the treatment of colorectal cancer liver metastases.

Systemic IFN-beta gene therapy results in long-term survival in mice with established colorectal liver metastases

Most patients succumbing to colorectal cancer fail with liver-predominant metastases. To make a clinical impact in this disease, a systemic or whole-liver therapy may be required, whereas most cancer gene therapy approaches are limited in their ability to treat beyond local disease. As a preclinical model for cancer gene therapy, recombinant adenovirus containing the human IFN-beta (hIFN-beta) cDNA was delivered systemically in nude mouse xenograft models of human colorectal cancer liver metastases. The vector targeted hepatocytes that produced high levels of hIFN-beta in the liver, resulting in a profound apoptotic response in the tumors and significant tumor regression. hIFN-beta gene therapy not only resulted in improved survival and long-term cure in a micrometastatic model, but provided similar benefits in a clinically relevant gross disease model. A similar recombinant adenovirus containing the murine IFN-beta (mIFN-beta) cDNA also resulted in a therapeutic response and improved survival in syngeneic mouse models of colorectal cancer liver metastases. Depletion studies demonstrate a contribution of natural killer cells to this therapeutic response. The toxicity of an adenoviral vector expressing murine IFN-beta in a syngeneic model is also presented. These encouraging results warrant further investigation of the use of cancer gene therapy for targeting metastatic disease.

Preliminary report of photodynamic therapy for intraperitoneal sarcomatosis

INTRODUCTION

Sarcomatosis is the disseminated intraperitoneal spread of sarcoma. It is a condition for which there is no effective treatment. Photodynamic therapy (PDT) is a cancer treatment modality that uses a photosensitizing agent and laser light to kill cells. We report our preliminary Phase II clinical trial experience using PDT for the treatment of intraperitoneal sarcomatosis.

METHODS

From May 1997 to December 1998 eleven patients received twelve PDT treatments for intraperitoneal sarcomatosis. Photofrin (PF) 2.5 mg/kg was administered intravenously 48 hours before surgical debulking to a maximum residual tumor size of less than 5 mm. Light therapy was administered at a fluence of 2.5 J/cm2 of 532 nm green light to the mesentery and serosa of the small bowel and colon; 5 J/cm2 of 630 nm red light to the stomach and duodenum; 7.5 J/cm2 of red light to the surface of the liver, spleen, and diaphragms; and 10 J/cm2 of red light to the retroperitoneal gutters and pelvis. Light fluence was measured with an on-line light dosimetry system. Response to treatment was evaluated by abdominal CT scan at 3 and 6 months, diagnostic laparoscopy at 3 to 6 months, and clinical examination every 3 months.

RESULTS

Adequate tumor debulking required an omentectomy in eight patients (73%), small bowel resection in seven patients (64%), colon resection in four patients (36%), splenectomy in one patient (9%), and a left spermatic cord resection in one patient. Five patients (45%) have no evidence of disease at follow-up (range, 1.7-17.3 months), including patients at 13.8 and 17.3 months examined by CT. Two patients (18%) died from disease progression. Four patients (36%) are alive with disease progression. Toxicities related to PDT included substantial postoperative fluid shifts with volume overload, transient thrombocytopenia, and elevated liver function tests. One patient suffered a postoperative pulmonary embolism complicated by adult respiratory distress syndrome (ARDS).

CONCLUSIONS

Debulking surgery with intraperitoneal PDT for sarcomatosis is feasible. Preliminary response data suggest prolonged relapse-free survival in some patients. Additional follow-up with more patients will be necessary for full evaluation of the added benefit of PDT and aggressive surgical debulking in these patients.

Gene therapy of metastatic disease: progress and prospects

Gene therapy remains a new and exciting therapy that holds the potential to impact the care of many diseases. Cancer gene therapy strategies encompass a major part of this developing field. Initial preclinical and phase I clinical trials have demonstrated the ability to transfer genetic material to cells in vitro and in vivo with resultant expression of biologically active protein. Most of these studies have involved direct injection or local installation of vector. A majority of patients succumbing to cancer do so because of metastatic disease. Clearly, to broaden the impact of cancer gene therapy on these patients' outcome, new strategies for targeting regional or systemic disease are required. This article offers a review of current vectors and therapeutic strategies along with the application of these in human cancers.

Phase II trial of debulking surgery and photodynamic therapy for disseminated intraperitoneal tumors

BACKGROUND

Photodynamic therapy (PDT) combines photosensitizer drug, oxygen, and laser light to kill tumor cells on surfaces. This is the initial report of our phase II trial, designed to evaluate the effectiveness of surgical debulking and PDT in carcinomatosis and sarcomatosis.

METHODS

Fifty-six patients were enrolled between April 1997 and January 2000. Patients were given Photofrin (2.5 mg/kg) intravenously 2 days before tumor-debulking surgery. Laser light was delivered to all peritoneal surfaces. Patients were followed with CT scans and laparoscopy to evaluate responses to treatment.

RESULTS

Forty-two patients were adequately debulked at surgery; these comprise the treatment group. There were 14 GI malignancies, 12 ovarian cancers and 15 sarcomas. Actuarial median survival was 21 months. Median time to recurrence was 3 months (range, 1-21 months). The most common serious toxicities were anemia (38%), liver function test (LFT) abnormalities (26%), and gastrointestinal toxicities (19%), and one patient died.

CONCLUSIONS

Photofrin PDT for carcinomatosis has been successfully administered to 42 patients, with acceptable toxicity. The median survival of 21 months exceeds our expectations; however, the relative contribution of surgical resection versus PDT is unknown. Deficiencies in photosensitizer delivery, tissue oxygenation, or laser light distribution leading to recurrences may be addressed through the future use of new photosensitizers.

Incidence of sentinel node metastasis in patients with thin primary melanoma (< or = 1 mm) with vertical growth phase

BACKGROUND

Patients with thin primary melanomas (< or = 1 mm) generally have an excellent prognosis. However, the presence of a vertical growth phase (VGP) adversely impacts the survival rate. We report on the rate of occurrence of nodal metastasis in patients with thin primary melanomas with a VGP who are offered sentinel lymph node (SLN) biopsy.

METHODS

Among 235 patients with clinically localized cutaneous melanomas who underwent successful SLN biopsy, 71 had lesions 1 mm or smaller with a VGP. The SLN was localized by using blue dye and a radiotracer. If negative for tumor by using hematoxylin and eosin staining, the SLN was further examined by immunohistochemistry.

RESULTS

The rate of occurrence of SLN metastasis was 15.2% in patients with melanomas deeper than 1 mm and 5.6% in patients with thin melanomas. Three patients with thin melanomas and a positive SLN had low-risk lesions, based on a highly accurate six-variable multivariate logistic regression model for predicting 8-year survival in stage I/II melanomas. The fourth patient had a low- to intermediate-risk lesion based on this model. At the time of the lymphadenectomy, one patient had two additional nodes with metastasis.

CONCLUSIONS

VGP in a melanoma 1 mm or smaller seems to be a risk factor for nodal metastasis. The risk of nodal disease may not be accurately predicted by the use of a multivariate logistic regression model that incorporates thickness, mitotic rate, regression, tumor-infiltrating lymphocytes, sex, and anatomical site. Patients with thin lesions having VGP should be evaluated for SLN biopsy and trials of adjuvant therapy when stage III disease is found.

Up-regulation of the proapoptotic mediators Bax and Bak after adenovirus-mediated p53 gene transfer in lung cancer cells

Overexpression of wild-type p53 in cancer cells by adenovirus-mediated p53 gene transfer can result in the induction of apoptosis. To identify the potential mediators of this p53-induced apoptosis, we examined apoptotic protein levels in human lung cancer cells after Adp53 gene transfer. We observed up-regulation of Bax and Bak protein levels 18-36 h after transduction with Adp53 in H1299, H358, and H322 lung cancer cells. Contrary to expected observations, no changes in Bcl-2 and Bcl-X(L) protein levels were observed. Morphological cell changes and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling staining showed evidence of apoptosis in all cell lines 48 h after transduction with Adp53. These results indicate that the induction of apoptosis by adenovirus-mediated p53 transfer may be mediated by the induction of proapoptotic mechanisms rather than suppression of antiapoptotic mechanisms.