Prediction of plasma ctDNA fraction and prognostic implications of liquid biopsy in advanced prostate cancer.

No consensus strategies exist for prognosticating metastatic castration-resistant prostate cancer (mCRPC). Circulating tumor DNA fraction (ctDNA%) is increasingly reported by commercial and laboratory tests but its utility for risk stratification is unclear. Here, we intersect ctDNA%, treatment outcomes, and clinical characteristics across 738 plasma samples from 491 male mCRPC patients from two randomized multicentre phase II trials and a prospective province-wide blood biobanking program. ctDNA% correlates with serum and radiographic metrics of disease burden and is highest in patients with liver metastases. ctDNA% strongly predicts overall survival, progression-free survival, and treatment response independent of therapeutic context and outperformed established prognostic clinical factors. Recognizing that ctDNA-based biomarker genotyping is limited by low ctDNA% in some patients, we leverage the relationship between clinical prognostic factors and ctDNA% to develop a clinically-interpretable machine-learning tool that predicts whether a patient has sufficient ctDNA% for informative ctDNA genotyping (available online: https://www.ctDNA.org ). Our results affirm ctDNA% as an actionable tool for patient risk stratification and provide a practical framework for optimized biomarker testing.

Comparative effectiveness of intra-articular therapies in knee osteoarthritis: a meta-analysis comparing platelet-rich plasma (PRP) with other treatment modalities.

Introduction: Knee osteoarthritis (KOA) is a progressive joint disease commonly treated with intra-articular injections, including platelet-rich plasma (PRP), hyaluronic acid (HA), or corticosteroids (CS). This updated meta-analysis aims to enhance the statistical power of the results and provide comprehensive clinical evidence that reflects the most current research. By doing so, the authors aim to suggest a reliable estimate for the development of guidelines, addressing the pressing need for effective and minimally invasive treatment options. Methods: PubMed, Scopus, clinicaltrials.gov, Cochrane Central were searched until March 2023, for randomized controlled trials (RCTs) comparing the effectiveness of intra-articular injectable therapies, including PRP, HA, CS, and placebo, in KOA. Data extraction involved baseline characteristics and outcome measures [Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores, Visual Analog Scale (VAS) pain scores, KOOS, and IKDC scores] at 1, 3, 6 and 12 months. Statistical analysis, including subgroup analysis, assessment of heterogeneity, and publication bias, was conducted using Review Manager. Results: Our meta-analysis of 42 studies involving 3696 patients demonstrated that PRP treatment resulted in significant pain relief compared to HA injections, as evidenced by improved WOMAC pain (MD: -0.74; 95% CI: -1.02 to -0.46; P≤0.00001; I 2=94%) and VAS pain (MD: -0.65; 95% CI: -1.24 to -0.06; P=0.03; I2=97%) outcomes. Similarly, PRP showed greater efficacy in reducing WOMAC pain (MD: -8.06; 95% CI: -13.62 to -2.51: P=0.004; I 2=96%) and VAS pain (MD: -1.11; 95% CI: -1.64 to -0.59; P≤0.0001; I 2=68%) compared to CS injections, with the most significant improvement observed at 6 months. Conclusions: PRP is an effective treatment for KOA. It provides symptomatic relief, has the potential to reduce disease progression, and has sustained effects up to 12 months. PRP offers superior pain relief and functional enhancement compared to CS and HA injections.

Evolution of Castration-Resistant Prostate Cancer in ctDNA during Sequential Androgen Receptor Pathway Inhibition.

PURPOSE: Cross-resistance renders multiple lines of androgen receptor (AR) signaling inhibitors increasingly futile in metastatic castration-resistant prostate cancer (mCRPC). We sought to determine acquired genomic contributors to cross-resistance. EXPERIMENTAL DESIGN: We collected 458 serial plasma cell-free DNA samples at baseline and progression timepoints from 202 patients with mCRPC receiving sequential AR signaling inhibitors (abiraterone and enzalutamide) in a randomized phase II clinical trial (NCT02125357). We utilized deep targeted and whole-exome sequencing to compare baseline and posttreatment somatic genomic profiles in circulating tumor DNA (ctDNA). RESULTS: Patient ctDNA abundance was correlated across plasma collections and independently prognostic for sequential therapy response and overall survival. Most driver alterations in established prostate cancer genes were consistently detected in ctDNA over time. However, shifts in somatic populations after treatment were identified in 53% of patients, particularly after strong treatment responses. Treatment-associated changes converged upon the AR gene, with an average 50% increase in AR copy number, changes in AR mutation frequencies, and a 2.5-fold increase in the proportion of patients carrying AR ligand binding domain truncating rearrangements. CONCLUSIONS: Our data show that the dominant AR genotype continues to evolve during sequential lines of AR inhibition and drives acquired resistance in patients with mCRPC.

Effectiveness of first-line abiraterone versus enzalutamide among patients ≥80 years of age with metastatic castration-resistant prostate cancer: A retrospective propensity score-weighted comparative cohort study.

BACKGROUND: Metastatic castration-resistant prostate cancer (mCRPC) disproportionately affects the elderly. There is limited data assessing the efficacy and tolerability of abiraterone acetate (AA) versus enzalutamide in this population. OBJECTIVE: To compare the clinical efficacy and tolerability of AA versus enzalutamide in patients ≥ 80 years with mCRPC. DESIGN, SETTING AND PARTICIPANTS: A retrospective propensity-weighted comparative cohort study of first-line AA versus enzalutamide among patients with mCRPC aged ≥80 years. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Inverse probability treatment weights based on propensity scores were generated to assess the treatment effect of AA versus enzalutamide on time to PSA progression (TTPP), time to progression (TTP) (first of PSA/radiographic/clinical progression) and overall survival using a weighted Cox proportional hazards model. PSA response rate (PSA RR) was compared between groups using Χ2. RESULTS AND LIMITATIONS: One hundred fifty-three patients received AA, and 125 received enzalutamide. Enzalutamide was associated with higher PSA RR (61.6% vs 43.8%, P < 0.004), and TTP (hazard ratio [HR] 0.66, 95% confidence interval [CI] 0.50-0.88, P = 0.01) but not TTPP (HR 0.73, 95% CI 0.53-1.01, P = 0.06). There were significantly more dose reductions with enzalutamide (22.9% vs 44.8%, P > 0.001) but there was no interaction between median proportion of full dose received and TTPP or TTP for either drug. Rates of treatment discontinuation (for reasons other than progression) were also significantly different between AA and enzalutamide (28.8% vs 40.8%, respectively, P = 0.04). The most common reason for dose reductions and discontinuation of enzalutamide was fatigue (30.4% and 5.6%, respectively). CONCLUSIONS: Despite more dose reductions and a higher treatment discontinuation rate, enzalutamide was associated with a higher PSA RR and longer time to progression, than AA. Given that clinical outcomes were not adversely impacted by decreased treatment exposure, dose modification may be a useful treatment strategy to balance toxicity and tolerance.

Targeted drug delivery systems: synthesis and in vitro bioactivity and apoptosis studies of gemcitabine-carbon dot conjugates.

Gemcitabine (GEM) is used to treat various cancers such as breast, pancreatic, non-small lung, ovarian, bladder, and cervical cancers. GEM, however, has the problem of non-selectivity. Water-soluble, fluorescent, and mono-dispersed carbon dots (CDs) were fabricated by ultrasonication of sucrose. The CDs were further conjugated with GEM through amide linkage. The physical and morphological properties of these carbon dot-gemcitabine (CD-GEM) conjugates were determined using different analytical techniques. In vitro cytotoxicity and apoptosis studies of CD-GEM conjugates were evaluated by various bioactivity assays on human cell lines, MCF-7 (human breast adenocarcinoma), and HeLa (cervical cancer) cell lines. The results of kinetic studies have shown a maximum drug loading efficacy of 17.0 mg of GEM per 50.0 mg of CDs. The CDs were found biocompatible, and the CD-GEM conjugates exhibited excellent bioactivity and exerted potent cytotoxicity against tumor cells with an IC50 value of 19.50 µg ml-1 in HeLa cells, which is lower than the IC50 value of pure GEM (∼20.10 µg ml-1). In vitro studies on CD-GEM conjugates demonstrated the potential to replace the conventional administration of GEM. CD-GEM conjugates are more stable, have a higher aqueous solubility, and are more cytotoxic as compared to GEM alone. The CD-GEM conjugates show reduced side effects in the normal cells along with excellent cellular uptake. Hence, CD-GEM conjugates are more selective toward cancerous cell lines as compared to non-cancerous cells. Also, the CD-GEM conjugates successfully induced early and late apoptosis in cancer cell lines and might be effective and safe to use for in vivo applications.

Efficient Removal of Pb(II) from Aqueous Solutions by Using Oil Palm Bio-Waste/MWCNTs Reinforced PVA Hydrogel Composites: Kinetic, Isotherm and Thermodynamic Modeling.

Polyvinyl alcohol (PVA) hydrogel are still restricted for some applications because their lower mechanical strength and thermal stability. The PVA-based composites are drawing attention for the removal of heavy metals based on their specific functionality in adsorption process. The main objective of this work is to synthesize oil palm bio-waste (OPB)/multiwalled carbon nanotubes (MWCNTs) reinforced PVA hydrogels in the presence of N,N'-methylenebisacrylamide (NMBA) as a crosslinking agent and ammonium persulfate (APS) as an initiator via simple in-situ polymerization technique. The as-prepared reinforced nanocomposites were characterized by FESEM, BET surface area, differential scanning calorimetry (DSC), TGA and FTIR analysis. The possible influence of OPB and MWCNTs on the tensile strength, elongation at break and elastic modulus of the samples were investigated. It was found that reinforced nanocomposites exhibited enhanced mechanical properties as compared to non-reinforced material. The evaluation of reinforced nanocomposites was tested by the removal of Pb(II) aqueous solutions in a batch adsorption system. The pseudo-second-order kinetic model was used to illustrate the adsorption kinetic results and Langmuir isotherm was more suitable to fit the equilibrium results providing maximum adsorption capacities. The evaluation of thermodynamic parameters describes the spontaneous, endothermic and chemisorption adsorption process while activation energy reveals the physical adsorption mechanism. Therefore, the coordination effects among OPB, MWCNTs and PVA polymer hydrogels can produce a promising adsorbent material for wastewater treatment applications.

Optimal sequencing of enzalutamide and abiraterone acetate plus prednisone in metastatic castration-resistant prostate cancer: a multicentre, randomised, open-label, phase 2, crossover trial.

BACKGROUND: Abiraterone acetate plus prednisone and enzalutamide are both used for the treatment of metastatic castration-resistant prostate cancer. We aimed to determine the best sequence in which to use both drugs, as well as their second-line efficacy. METHODS: In this multicentre, randomised, open-label, phase 2, crossover trial done in six cancer centres in British Columbia, Canada, we recruited patients aged 18 years or older with newly-diagnosed metastatic castration-resistant prostate cancer without neuroendocrine differentiation and Eastern Cooperative Oncology Group performance status 2 or less. Patients were randomly assigned (1:1) using a computer-generated random number table to receive either abiraterone acetate 1000 mg orally once daily plus prednisone 5 mg orally twice daily until PSA progression followed by crossover to enzalutamide 160 mg orally once daily (group A), or the opposite sequence (group B). Treatment was not masked to investigators or participants. Primary endpoints were time to second PSA progression and PSA response (≥30% decline from baseline) on second-line therapy, analysed by intention-to-treat in all randomly assigned patients and in patients who crossed over, respectively. The trial is registered with ClinicalTrials.gov, NCT02125357. FINDINGS: Between Oct 21, 2014, and Dec 13, 2016, 202 patients were enrolled and randomly assigned to either group A (n=101) or group B (n=101). At the time of data cutoff, 73 (72%) patients in group A and 75 (74%) patients in group B had crossed over. Time to second PSA progression was longer in group A than in group B (median 19·3 months [95% CI 16·0-30·5] vs 15·2 months [95% CI 11·9-19·8] months; hazard ratio 0·66, 95% CI 0·45-0·97, p=0·036), at a median follow-up of 22·8 months (IQR 10·3-33·4). PSA responses to second-line therapy were seen in 26 (36%) of 73 patients for enzalutamide and three (4%) of 75 for abiraterone (χ2 p<0·0001). The most common grade 3-4 adverse events throughout the trial were hypertension (27 [27%] of 101 patients in group A vs 18 [18%] of 101 patients in group B) and fatigue (six [10%] vs four [4%]). Serious adverse events were reported in 15 (15%) of 101 patients in group A and 20 (20%) of 101 patients in group B. There were no treatment-related deaths. INTERPRETATION: Enzalutamide showed activity as a second-line novel androgen receptor pathway inhibitor, whereas abiraterone acetate did not, leading to a longer time to second PSA progression for the sequence of abiraterone followed by enzalutamide than with the opposite treatment sequence. Our data suggest that using a sequencing strategy of abiraterone acetate followed by enzalutamide provides the greatest clinical benefit. FUNDING: Canadian Cancer Society Research Institute, Prostate Cancer Canada, Movember Foundation, Prostate Cancer Foundation, Terry Fox New Frontiers Program, BC Cancer Foundation, Jane and Aatos Erkko Foundation, Janssen, and Astellas.

Clinical effectiveness of docetaxel for castration-sensitive prostate cancer in a real-world population-based analysis.

BACKGROUND: Adding docetaxel to androgen deprivation therapy (ADT) for the treatment of metastatic castration-sensitive prostate cancer (mCSPC) has known efficacy, with an overall survival benefit in Phase III clinical trials. The effectiveness of docetaxel with ADT in the general patient population remains undefined. PATIENTS AND METHODS: We conducted a population-based retrospective review using the British Columbia Provincial Pharmacy Database. To be included, patients had to have castration-sensitive prostate cancer not previously treated (except in the adjuvant setting) and have received at least one cycle of docetaxel, with complete records available for review. Safety and clinical effectiveness were evaluated. RESULTS: From April 2015 to February 2017, we identified 183 cases; 156 met inclusion criteria. Most patients had high-volume disease (80%). All 6 planned docetaxel cycles were delivered in 126 cases (81%). Dose reductions and delays were required in 39% and 16% of cases. Grade 3-4 adverse events were noted in 40%, with no treatment-related deaths. The rate of febrile neutropenia was 18% and was significantly associated with the presence of high-volume disease (P = 0.038). PSA ≤ 0.2 ng/L was achieved in 27% of patients after 6 months of ADT and maintained in 16% after 12 months. Patients with over 20 bone metastases had worse time to castration resistant prostate cancer (CRPC) and time to treatment for CRPC, and a trend toward worse overall survival. CRPC developed in 41% within 1 year, with a median time to CRPC of 14.4 months. Treatment for CRPC was given in 84 cases, with 90% receiving either abiraterone or enzalutamide in the first-line, with a PSA decline ≥50% occurring in 47%. CONCLUSIONS: The effectiveness of docetaxel with ADT in a general population of patients with mCSPC was associated with poorer outcomes and high rates of toxicity compared to the published studies. Response rates to first-line treatment for mCRPC with abiraterone or enzalutamide appear similar to reported outcomes.

Health-related Quality of Life for Abiraterone Plus Prednisone Versus Enzalutamide in Patients with Metastatic Castration-resistant Prostate Cancer: Results from a Phase II Randomized Trial.

BACKGROUND: Abiraterone and enzalutamide are associated with side effects that may impair health-related quality of life (HRQoL). OBJECTIVE: To assess patient-reported HRQoL, depression symptoms, and cognitive function for abiraterone versus enzalutamide. DESIGN, SETTING, AND PARTICIPANTS: We randomized 202 patients in a phase II study of abiraterone versus enzalutamide for first-line treatment of metastatic castration-resistant prostate cancer (ClinicalTrials.gov: NCT02125357). INTERVENTION: Patients completed Functional Assessment of Cancer Therapy-Prostate (FACT-P) and Patient Health Questionnaire-9 (PHQ-9) questionnaires, and Montreal Cognitive Assessment (MoCA) cognitive assessments at baseline and on treatment. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: To compare the change in FACT-P scores over time between treatment arms, we used a mixed model for repeated measures (MMRM). For FACT-P domains where there was an interaction between the treatment arm and age, we constructed separate models for patients aged <75 and ≥75yr. We compared the proportion of patients with clinically meaningful change from baseline for FACT-P, and the proportion of patients with an abnormal score and median change from baseline for PHQ-9 and MoCA using Fisher's exact test and Mann-Whitney U test. RESULTS AND LIMITATIONS: In the MMRM analysis, there was a positive test for interaction in the treatment arm by age for total FACT-P (p=0.048). FACT-P change from baseline over time was better for abiraterone than for enzalutamide in the ≥75-yr model (p=0.003), with no difference in the <75-yr model (p>0.9). A higher proportion of patients experienced clinically meaningful worsening with enzalutamide for the physical and functional well-being domains (37% vs 21%, p=0.013; 39% vs 23%, p=0.015). The distribution of change in PHQ-9 scores from baseline favored abiraterone at weeks 4, 8, and 12. These analyses were not prespecified, and results should be considered to be hypothesis generating. CONCLUSIONS: Patient-reported outcomes favored abiraterone compared with enzalutamide with differences in FACT-P HRQoL and PHQ-9 depression scores. Differences in the total FACT-P scores were seen only in the elderly patient subgroup. PATIENT SUMMARY: In this report, we examined the change in patient-reported quality-of-life scores from the start of treatment over time for patients treated with abiraterone versus enzalutamide for metastatic castration-resistant prostate cancer. We found that elderly patients treated with abiraterone had better quality of life over time, with no difference between treatments for the younger subgroup of patients.

Molecular Diagnostics in Colorectal Carcinoma: Advances and Applications for 2018.

The molecular pathogenesis and classification of colorectal carcinoma are based on the traditional adenomaecarcinoma sequence, serrated polyp pathway, and microsatellite instability (MSI). The genetic basis for hereditary nonpolyposis colorectal cancer is the detection of mutations in the MLH1, MSH2, MSH6, PMS2, and EPCAM genes. Genetic testing for Lynch syndrome includes MSI testing, methylator phenotype testing, BRAF mutation testing, and molecular testing for germline mutations in MMR genes. Molecular makers with predictive and prognostic implications include quantitative multigene reverse transcriptase polymerase chain reaction assay and KRAS and BRAF mutation analysis. Mismatch repair-deficient tumors have higher rates of programmed death-ligand 1 expression. Cell-free DNA analysis in fluids are proving beneficial for diagnosis and prognosis in these disease states towards effective patient management.

Molecular Diagnostics in the Neoplasms of Small Intestine and Appendix: 2018 Update.

Neoplasms of the small intestine are rare in comparison with colorectal tumors. The most common tumor types arising in the small intestine are adenocarcinomas, well-differentiated neuroendocrine tumors, gastrointestinal stromal tumors, and lymphoma. Primary appendiceal neoplasms are rare and found in less than 2% of appendectomy specimens with an incidence of approximately 1.2 cases per 100,000 people per year in the United States. This article explores molecular diagnostics in the neoplasms of small intestine and appendix.

Molecular Diagnostics in Esophageal and Gastric Neoplasms: 2018 Update.

Esophageal cancer (EC) is rapidly increasing in incidence in the United States. Genetic changes associated with the development of EC involve the p16, p53, and APC genes. Human epidermal growth factor 2 (HER-2) overexpression is seen in gastroesophageal junction carcinoma and a subset gastric carcinoma (GC). Interestingly, up to 50% cases of GC are related to Helicobacter pylori infection and up to 16% are related to EBV infection. Microsatellite instability is observed in up to 39% of GC and cell free nucleic acid analysis provides additional opportunities for diagnosis and prognosis of disease.

A randomized phase II study of pelareorep and docetaxel or docetaxel alone in men with metastatic castration resistant prostate cancer: CCTG study IND 209.

BACKGROUND: Pelareorep is an oncolytic virus with activity in many cancers including prostate. It has in vitro synergism with microtubule-targeted agents. We undertook a clinical trial evaluating pelareorep in mCRPC patients receiving docetaxel. PATIENTS AND METHODS: In this randomized, open-label phase II study, patients received docetaxel 75mg/m2 on day 1 of a 21-day cycle and prednisone 5mg twice daily, in combination with pelareorep (arm A) or alone (arm B). The primary endpoint was 12 weeks lack of disease progression rate (LPD). RESULTS: Eighty-five pts were randomized. Median age was 69, ECOG performance status was 0/1/2 in 31%/66%/3% of patients. Bone/regional lymph node/liver metastases were present in 98%/24%/6%. The median prognostic score was slightly higher in Arm A (144 vs. 129 p= 0.005). Adverse events were as expected but more prevalent in arm A. The 12-week LPD rate was 61% and 52.4% in arms A/B (p=0.51). Median survival was 19.1 on Arm A and 21.1 months on Arm B (HR 1.83; 95% CI 0.96 to 3.52; p=0.06). No survival benefit of pelareorep was found. CONCLUSION: Pelareorep with docetaxel was tolerable with comparable LPD in both arms but response and survival were inferior and so this combination does not merit further study.

Circulating Tumor DNA Genomics Correlate with Resistance to Abiraterone and Enzalutamide in Prostate Cancer.

Primary resistance to androgen receptor (AR)-directed therapies in metastatic castration-resistant prostate cancer (mCRPC) is poorly understood. We randomized 202 patients with treatment-naïve mCRPC to abiraterone or enzalutamide and performed whole-exome and deep targeted 72-gene sequencing of plasma cell-free DNA prior to therapy. For these agents, which have never been directly compared, time to progression was similar. Defects in BRCA2 and ATM were strongly associated with poor clinical outcomes independently of clinical prognostic factors and circulating tumor DNA abundance. Somatic alterations in TP53, previously linked to reduced tumor dependency on AR signaling, were also independently associated with rapid resistance. Although detection of AR amplifications did not outperform standard prognostic biomarkers, AR gene structural rearrangements truncating the ligand binding domain were identified in several patients with primary resistance. These findings establish genomic drivers of resistance to first-line AR-directed therapy in mCRPC and identify potential minimally invasive biomarkers.Significance: Leveraging plasma specimens collected in a large randomized phase II trial, we report the relative impact of common circulating tumor DNA alterations on patient response to the most widely used therapies for advanced prostate cancer. Our findings suggest that liquid biopsy analysis can guide the use of AR-targeted therapy in general practice. Cancer Discov; 8(4); 444-57. ©2018 AACR.See related commentary by Jayaram et al., p. 392This article is highlighted in the In This Issue feature, p. 371.

PANCREOX: A Randomized Phase III Study of Fluorouracil/Leucovorin With or Without Oxaliplatin for Second-Line Advanced Pancreatic Cancer in Patients Who Have Received Gemcitabine-Based Chemotherapy.

Purpose The standard of care for second-line therapy in patients with advanced pancreatic cancer after gemcitabine-based therapy is not clearly defined. The CONKO-003 phase III study reported a survival benefit with second-line fluorouracil (FU) and oxaliplatin using the oxaliplatin, folinic acid, and FU (OFF) regimen. 1 PANCREOX was a phase III multicenter trial to evaluate the benefit of FU and oxaliplatin administered as modified FOLFOX6 (mFOLFOX6; infusional fluorouracil, leucovorin, and oxaliplatin) versus infusional FU/leucovorin (LV) in this setting. Patients and Methods Patients with confirmed advanced pancreatic cancer who were previously treated with gemcitabine therapy and with an Eastern Cooperative Oncology Group performance status of 0-2 were eligible. A total of 108 patients were randomly assigned to receive biweekly mFOLFOX6 or infusional FU/LV until progression. Progression-free survival (PFS) was the primary end point. Results Baseline patient characteristics were similar in both arms. No difference was observed in PFS (median, 3.1 months v 2.9 months; P = .99). Overall survival (OS) was inferior in patients assigned to mFOLFOX6 (median, 6.1 months v 9.9 months; P = .02). Increased toxicity was observed with the addition of oxaliplatin, with grade 3/4 adverse events occurring in 63% of patients who received mFOLFOX6 and 11% of those who received FU/LV. More patients in the mFOLFOX6 arm withdrew from study due to adverse events than in the FU/LV arm (20% v 2%), whereas the use of postprogression therapy was significantly higher in the FU/LV arm (25% v 7%; P = .015). No significant differences were observed in time to deterioration on the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 global health scale. Conclusion No benefit was observed with the addition of oxaliplatin, administered as mFOLFOX6, versus infusional FU/LV in patients with advanced pancreatic cancer previously treated with first-line gemcitabine.

Molecular diagnostics in colorectal carcinoma.

Molecular pathogenesis and classification of colorectal carcinoma are based on the adenoma-carcinoma sequence in the Vogelstein model, serrated polyp pathway, and microsatellite instability. The genetic basis for hereditary nonpolyposis colorectal cancer is based on detection of genetic mutations. Genetic testing for Lynch syndrome includes microsatellite instability, methylator phenotyping, BRAF mutation, and molecular testing. Molecular makers include quantitative multigene reverse transcriptase-polymerase chain reaction assay and KRAS and BRAF mutation analysis. Potential biomarkers include one-step nucleic acid amplification and epigenetic inactivation of endothelin 2 and endothelin 3 in colon cancer. Molecular screening approaches in colorectal cancer using stool DNA are under investigation.

Molecular diagnostics in the neoplasms of small intestine and appendix.

Adenocarcinoma of the small intestine is relatively rare in comparison to colorectal carcinoma. Adenocarcinoma of the small intestine arises through the adenoma-carcinoma sequence in the colon. However, adenocarcinomas arising in the background of inflammatory bowel disease develop through the dysplasia-carcinoma sequence. Most of the cases occur in the duodenum; however, adenocarcinoma occurring in association with Crohn disease is more common in the ileum.

Molecular diagnostics in esophageal and gastric neoplasms.

Esophageal carcinoma is the most rapidly increasing tumor in incidence in the United States. It has an established association with a precursor lesion (Barrett esophagus). Gastric carcinoma (GC) is the second leading cause of cancer death in the world. The prognosis for patients with advanced stage GC and esophageal carcinoma is poor. Human epidermal growth factor 2 (HER-2) overexpression is seen in gastroesophageal junction carcinoma and a subset of GC. HER-2 overexpressing tumors are eligible for HER-2 targeted therapies, which lead to a better survival in these patients.

Molecular diagnostics in the neoplasms of the pancreas, liver, gall bladder, and extrahepatic biliary tract.

Pancreatic neoplasms, including ductal adenocarcinoma, intraductal papillary mucinous neoplasm, solid pseudopapillary neoplasm, pancreatic endocrine neoplasms, acinar cell carcinoma, and ampullary carcinoma, are associated with different genetic abnormalities. Liver neoplasms, including hepatic adenomas, hepatocellular carcinomas, and cholangiocarcinomas, are associated with identifiable risk factors and genetic changes. Gall bladder adenomas and adenocarcinomas arise from distinct molecular pathways. The molecular abnormalities seen in these tumors are not used routinely in the molecular diagnostic laboratory.

Current applications of molecular genetic technologies to the diagnosis and treatment of cutaneous melanocytic neoplasms.

Decades of research have brought knowledge to a point where physicians are beginning to understand human disease processes like oncogenesis on a molecular level. Molecular technologies are now being applied to current clinical settings such as the diagnosis and treatment of cutaneous melanocytic neoplasms. In particular, dermatopathologists are using fluorescence in situ hybridization to aid in the diagnosis of challenging melanocytic neoplasms. Pathologists are working with oncologists to use the sequences of specific genes in melanomas to choose more effective treatments. This article discusses how these technologies are altering the ways in which cutaneous melanocytic neoplasms are diagnosed and treated.