Beyond a vestigial organ: effects of the appendix on gut microbiome and colorectal cancer

The role of appendectomy in the pathogenesis of colorectal cancer (CRC) is a recent topic of contention. Given that appendectomy remains one of the most commonly performed operations and a first-line management strategy of acute appendicitis, it is inherently crucial to elucidate the association between prior appendectomy and subsequent development of CRC, as there may be long-term health repercussions. In this review, we summarize the data behind the relationship of CRC in post-appendectomy patients, discuss the role of the microbiome in relation to appendectomy and CRC pathogenesis, and provide an appraisal of our current understanding of the function of the appendix. We seek to piece together the current landscape surrounding the microbiome and immunological changes in the colon post-appendectomy and suggest a direction for future research involving molecular, transcriptomic, and immunologic analysis to complement our current understanding of the alterations in gut microbiome.

Nivolumab Plus Chemotherapy in Epidermal Growth Factor Receptor-Mutated Metastatic Non-Small-Cell Lung Cancer After Disease Progression on Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors: Final Results of CheckMate 722

PURPOSE

The phase III CheckMate 722 trial (ClinicalTrials.gov identifier: NCT02864251) evaluated nivolumab plus chemotherapy versus chemotherapy in patients with epidermal growth factor receptor (EGFR)-mutated metastatic non-small-cell lung cancer (NSCLC) after disease progression on EGFR tyrosine kinase inhibitors (TKIs).

METHODS

Patients with disease progression after first- or second-generation EGFR TKI therapy (without EGFR T790M mutation) or osimertinib (with/without T790M mutation) were randomly assigned 1:1 to nivolumab (360 mg once every 3 weeks) plus platinum-doublet chemotherapy (once every 3 weeks) or platinum-doublet chemotherapy alone (once every 3 weeks) for four cycles. Primary end point was progression-free survival (PFS). Secondary end points included 9- and 12-month PFS rates, overall survival (OS), objective response rate (ORR), and duration of response (DOR).

RESULTS

Overall, 294 patients were randomly assigned. At final analysis (median follow-up, 38.1 months), PFS was not significantly improved with nivolumab plus chemotherapy versus chemotherapy (median, 5.6 v 5.4 months; hazard ratio [HR], 0.75 [95% CI, 0.56 to 1.00]; P = .0528), with 9- and 12-month PFS rates of 25.9% versus 19.8%, and 21.2% versus 15.9%, respectively. Post hoc PFS subgroup analyses showed a trend favoring nivolumab plus chemotherapy in patients with tumors harboring sensitizing EGFR mutations (HR, 0.72 [95% CI, 0.54 to 0.97]), one line of previous EGFR TKI (0.72 [95% CI, 0.54 to 0.97]), or both (0.64 [95% CI, 0.47 to 0.88]). Median OS was 19.4 months with nivolumab plus chemotherapy versus 15.9 months with chemotherapy, while ORR was 31.3% versus 26.7%, and median DOR was 6.7 versus 5.6 months, respectively. Grade 3/4 treatment-related adverse events occurred in 44.7% and 29.4% of patients treated with nivolumab plus chemotherapy and chemotherapy alone, respectively.

CONCLUSION

Nivolumab plus chemotherapy did not significantly improve PFS versus chemotherapy in patients with EGFR-mutated metastatic NSCLC previously treated with EGFR TKIs. No new safety signals were identified.

Toripalimab Plus Chemotherapy for Recurrent or Metastatic Nasopharyngeal Carcinoma: The JUPITER-02 Randomized Clinical Trial

Importance

There are currently no therapies approved by the US Food and Drug Administration for nasopharyngeal carcinoma (NPC). Gemcitabine-cisplatin is the current standard of care for the first-line treatment of recurrent or metastatic NPC (RM-NPC).

Objective

To determine whether toripalimab in combination with gemcitabine-cisplatin will significantly improve progression-free survival and overall survival as first-line treatment for RM-NPC, compared with gemcitabine-cisplatin alone.

Design, Setting, and Participants

JUPITER-02 is an international, multicenter, randomized, double-blind phase 3 study conducted in NPC-endemic regions, including mainland China, Taiwan, and Singapore. From November 10, 2018, to October 20, 2019, 289 patients with RM-NPC with no prior systemic chemotherapy in the RM setting were enrolled from 35 participating centers.

Interventions

Patients were randomized (1:1) to receive toripalimab (240 mg [n = 146]) or placebo (n = 143) in combination with gemcitabine-cisplatin for up to 6 cycles, followed by maintenance with toripalimab or placebo until disease progression, intolerable toxicity, or completion of 2 years of treatment.

Main Outcome

Progression-free survival as assessed by a blinded independent central review. Secondary end points included objective response rate, overall survival, progression-free survival assessed by investigator, duration of response, and safety.

Results

Among the 289 patients enrolled (median age, 46 [IQR, 38-53 years; 17% female), at the final progression-free survival analysis, toripalimab treatment had a significantly longer progression-free survival than placebo (median, 21.4 vs 8.2 months; HR, 0.52 [95% CI, 0.37-0.73]). With a median survival follow-up of 36.0 months, a significant improvement in overall survival was identified with toripalimab over placebo (hazard ratio [HR], 0.63 [95% CI, 0.45-0.89]; 2-sided P = .008). The median overall survival was not reached in the toripalimab group, while it was 33.7 months in the placebo group. A consistent effect on overall survival, favoring toripalimab, was found in subgroups with high and low PD-L1 (programmed death-ligand 1) expression. The incidence of all adverse events, grade 3 or greater adverse events, and fatal adverse events were similar between the 2 groups. However, adverse events leading to discontinuation of toripalimab or placebo (11.6% vs 4.9%), immune-related adverse events (54.1% vs 21.7%), and grade 3 or greater immune-related adverse events (9.6% vs 1.4%) were more frequent in the toripalimab group.

Conclusions and Relevance

The addition of toripalimab to chemotherapy as first-line treatment for RM-NPC provided statistically significant and clinically meaningful progression-free survival and overall survival benefits compared with chemotherapy alone, with a manageable safety profile. These findings support the use of toripalimab plus gemcitabine-cisplatin as the new standard of care for this patient population.

Trial Registration

ClinicalTrials.gov Identifier: NCT03581786.

Landscape of germline pathogenic variants in patients with dual primary breast and lung cancer

BACKGROUND

Cancer predisposition is most often studied in the context of single cancers. However, inherited cancer predispositions can also give rise to multiple primary cancers. Yet, there is a paucity of studies on genetic predisposition in multiple primary cancers, especially those outside of well-defined cancer predisposition syndromes. This study aimed to identify germline variants associated with dual primary cancers of the breast and lung.

METHODS

Exome sequencing was performed on germline DNA from 55 Singapore patients (52 [95%] never-smokers) with dual primaries in the breast and lung, confirmed by histopathology. Using two large control cohorts: the local SG10K_Health (n = 9770) and gnomAD non-cancer East Asians (n = 9626); and two additional local case cohorts of early-onset or familial breast cancer (n = 290), and lung cancer (n = 209), variants were assessed for pathogenicity in accordance with ACMG/AMP guidelines. In particular, comparisons were made with known pathogenic or likely pathogenic variants in the ClinVar database, pathogenicity predictions were obtained from in silico prediction software, and case-control association analyses were performed.

RESULTS

Altogether, we identified 19 pathogenic or likely pathogenic variants from 16 genes, detected in 17 of 55 (31%) patients. Six of the 19 variants were identified using ClinVar, while 13 variants were classified pathogenic or likely pathogenic using ACMG/AMP guidelines. The 16 genes include well-known cancer predisposition genes such as BRCA2, TP53, and RAD51D; but also lesser known cancer genes EXT2, WWOX, GATA2, and GPC3. Most of these genes are involved in DNA damage repair, reaffirming the role of impaired DNA repair mechanisms in the development of multiple malignancies. These variants warrant further investigations in additional populations.

CONCLUSIONS

We have identified both known and novel variants significantly enriched in patients with primary breast and lung malignancies, expanding the body of known cancer predisposition variants for both breast and lung cancer. These variants are mostly from genes involved in DNA repair, affirming the role of impaired DNA repair in the predisposition and development of multiple cancers.

Whole-exome sequencing of BRCA-negative breast cancer patients and case-control analyses identify variants associated with breast cancer susceptibility

BACKGROUND

For the majority of individuals with early-onset or familial breast cancer referred for genetic testing, the genetic basis of their familial breast cancer remains unexplained. To identify novel germline variants associated with breast cancer predisposition, whole-exome sequencing (WES) was performed.

METHODS

WES on 290 BRCA1/BRCA2-negative Singaporeans with early-onset breast cancer and/or a family history of breast cancer was done. Case-control analysis against the East-Asian subpopulation (EAS) from the Genome Aggregation Database (gnomAD) identified variants enriched in cases, which were further selected by occurrence in cancer gene databases. Variants were further evaluated in repeated case-control analyses using a second case cohort from the database of Genotypes and Phenotypes (dbGaP) comprising 466 early-onset breast cancer patients from the United States, and a Singapore SG10K_Health control cohort.

RESULTS

Forty-nine breast cancer-associated germline pathogenic variants in 37 genes were identified in Singapore cases versus gnomAD (EAS). Compared against SG10K_Health controls, 13 of 49 variants remain significantly enriched (False Discovery Rate (FDR)-adjusted p < 0.05). Comparing these 49 variants in dbGaP cases against gnomAD (EAS) and SG10K_Health controls revealed 23 concordant variants that were significantly enriched (FDR-adjusted p < 0.05). Fourteen variants were consistently enriched in breast cancer cases across all comparisons (FDR-adjusted p < 0.05). Seven variants in GPRIN2, NRG1, MYO5A, CLIP1, CUX1, GNAS and MGA were confirmed by Sanger sequencing.

CONCLUSIONS

In conclusion, we have identified pathogenic variants in genes associated with breast cancer predisposition. Importantly, many of these variants were significant in a second case cohort from dbGaP, suggesting that the strategy of using case-control analysis to select variants could potentially be utilized for identifying variants associated with cancer susceptibility.

Toripalimab or placebo plus chemotherapy as first-line treatment in advanced nasopharyngeal carcinoma: a multicenter randomized phase 3 trial

Gemcitabine-cisplatin (GP) chemotherapy is the standard first-line systemic treatment for recurrent or metastatic nasopharyngeal carcinoma (RM-NPC). In this international, double-blind, phase 3 trial (ClinicalTrials.gov identifier: NCT03581786), 289 patients with RM-NPC and no previous chemotherapy for recurrent or metastatic disease were randomized (1/1) to receive either toripalimab, a monoclonal antibody against human programmed death-1 (PD-1), or placebo in combination with GP every 3 weeks for up to six cycles, followed by monotherapy with toripalimab or placebo. The primary endpoint was progression-free survival (PFS) as assessed by a blinded independent review committee according to RECIST v.1.1. At the prespecified interim PFS analysis, a significant improvement in PFS was detected in the toripalimab arm compared to the placebo arm: median PFS of 11.7 versus 8.0 months, hazard ratio (HR) = 0.52 (95% confidence interval (CI): 0.36-0.74), P = 0.0003. An improvement in PFS was observed across key subgroups, including PD-L1 expression. As of 18 February 2021, a 40% reduction in risk of death was observed in the toripalimab arm compared to the placebo arm (HR = 0.603 (95% CI: 0.364-0.997)). The incidence of grade ≥3 adverse events (AEs) (89.0 versus 89.5%), AEs leading to discontinuation of toripalimab/placebo (7.5 versus 4.9%) and fatal AEs (2.7 versus 2.8%) was similar between the two arms; however, immune-related AEs (39.7 versus 18.9%) and grade ≥3 infusion reactions (7.5 versus 0.7%) were more frequent in the toripalimab arm. In conclusion, the addition of toripalimab to GP chemotherapy as a first-line treatment for patients with RM-NPC provided superior PFS compared to GP alone, and with a manageable safety profile.

Outcome of advanced lung cancer with central airway obstruction versus without central airway obstruction

Patients with central airway obstruction (CAO) from advanced lung cancer present with significant morbidity and are assumed to have lower survival. Hence, they are offered only palliative support. We asked if patients who have advanced lung cancer with CAO (recanalised and treated) will behave similarly to those with advanced lung cancer without CAO. This study was a retrospective review of the medical records of the patients managed for advanced lung cancer during 2010 and 2015 at our institution. 85 patients were studied. Median survival and 1-, 2- and 5-year survival were 5.8 months, 30.3%, 11.7% and 2.3% versus 9.3 months, 35.7%, 9.6% and 4.7%, respectively, in the CAO and no CAO groups (p=0.30). More patients presented with respiratory failure (15 (35%) versus none; p=0.0001) and required assisted mechanical ventilation (10 (23.3%) versus none; p=0.001) in the CAO group compared with the no CAO group. Fewer patients received chemotherapy in the CAO group (11 (25.5%)) compared with the no CAO group (23 (54.7%); p=0.008). There was no difference in survival among patients with advanced lung cancer whether they presented with CAO or without CAO. Survival was similar to those without CAO in patients with recanalised CAO despite greater morbidity and lesser use of chemotherapy, strongly advocating bronchoscopic recanalisation of CAO. These findings dispel the nihilism associated with such cases.

Optimisation of pharmacy content in clinical cancer research protocols: Experience of the United Kingdom Chemotherapy and Pharmacy Advisory Service

Background

Clarity and accuracy of the pharmacy aspects of cancer clinical trial protocols is essential. Inconsistencies and ambiguities in such protocols have the potential to delay research and jeopardise both patient safety and collection of credible data. The Chemotherapy and Pharmacy Advisory Service was established by the UK National Cancer Research Network, currently known as National Institute for Health Research Clinical Research Network, to improve the quality of pharmacy-related content in cancer clinical research protocols. This article reports the scope of Chemotherapy and Pharmacy Advisory Service, its methodology of mandated protocol review and pharmacy-related guidance initiatives and its current impact.

Methods

Over a 6-year period (2008–2013) since the inception of Chemotherapy and Pharmacy Advisory Service, cancer clinical trial protocols were reviewed by the service, prior to implementation at clinical trial sites. A customised Review Checklist was developed and used by a panel of experts to standardise the review process and report back queries and inconsistencies to chief investigators. Based on common queries, a Standard Protocol Template comprising specific guidance on drug-related content and a Pharmacy Manual Template were developed. In addition, a guidance framework was established to address ‘ad hoc’ pharmacy-related queries. The most common remarks made at protocol review have been summarised and categorised through retrospective analysis. In order to evaluate the impact of the service, chief investigators were asked to respond to queries made at protocol review and make appropriate changes to their protocols. Responses from chief investigators have been collated and acceptance rates determined.

Results

A total of 176 protocols were reviewed. The median number of remarks per protocol was 26, of which 20 were deemed clinically relevant and mainly concerned the drug regimen, support medication, frequency and type of monitoring and drug supply aspects. Further analysis revealed that 62% of chief investigators responded to the review. All responses were positive with an overall acceptance rate of 89% of the proposed protocol changes.

Conclusion

Review of pharmacy content of cancer clinical trial protocols is feasible and exposes many undetected clinically relevant issues that could hinder efficient trial conduct. Our service audit revealed that the majority of suggestions were effectively incorporated in the final protocols. The refinement of existing and development of new pharmacy-related guidance documents by Chemotherapy and Pharmacy Advisory Service might aid in better and safer clinical research.

Safety and tolerability of the poly(ADP-ribose) polymerase (PARP) inhibitor, olaparib (AZD2281) in combination with topotecan for the treatment of patients with advanced solid tumors: a phase I study

BACKGROUND

The aim of this phase I study was to determine the safety and tolerability and to establish the maximum tolerated dose (MTD) of orally administered olaparib (AZD2281) in combination with topotecan in patients with advanced solid tumors.

PATIENTS AND METHODS

Patients aged ≥ 18 years with histologically or cytologically diagnosed advanced solid tumors for whom no suitable effective therapy exists were included. Patients in four cohorts received topotecan (0.5 mg/m(2)/day × 3 days or 1.0 mg/m(2)/day × 3 days) intravenously in combination with oral olaparib 50, 100 or 200 mg bid for six cycles. The primary objectives were to determine the safety and tolerability and to establish the MTD of olaparib in combination with topotecan.

RESULTS

Twenty-one patients were enrolled and 19 received treatment. Dose-limiting toxicities were neutropenia and thrombocytopenia. The MTD was established as topotecan 1.0 mg/m(2)/day × 3 days plus olaparib 100 mg bid. The most common adverse events (AEs) included fatigue and gastrointestinal events. There was an olaparib and topotecan dose-related increase in neutropenia which was dose limiting.

CONCLUSIONS

Further development of olaparib and topotecan in combination was not explored due to dose-limiting hematological AEs and the resulting sub-therapeutic MTD.

Oxaliplatin-induced coronary artery spasm: first report of an important side-effect

A 67-year-old woman with metastatic colorectal cancer was given her first oxaliplatin infusion as part of the XELOX protocol. She developed chest pain with ECG changes leading subsequently to a diagnosis of coronary artery spasm. To our knowledge, this is the first report of oxaliplatin-induced coronary artery spasm.

Survey of the use and clinical effectiveness of HPA-1a/5b-negative platelet concentrates in proven or suspected platelet alloimmunization

The optimal treatment of neonatal alloimmune thrombocytopenia (NAIT) is the transfusion of compatible donor platelets. The National Blood Service in England has established panels of "accredited" donors negative for human platelet antigens HPA-1a and HPA-5b, the most commonly implicated alloantigens. We have retrospectively surveyed the frequency of use and clinical effectiveness of donations collected over a 13-month period from the Oxford accredited panel. Ninety-five per cent of hyperconcentrated platelets (HPCs) collected were issued, all for intrauterine transfusion to fetuses at risk of NAIT due to the presence of maternal platelet alloantibodies and previously affected siblings. Thirty-one per cent of paediatric platelet concentrates (PPCs) collected were issued, of which 57% were used for cases of suspected NAIT. Fifty-four per cent of adult therapeutic doses collected were issued; 5% of these were used in cases of suspected NAIT or proven post-transfusion purpura (PTP). Good increments were seen in most NAIT cases transfused with HPCs or PPCs, and a moderate increment in the one PTP case. We conclude that the establishment of accredited panels is justified and enables delivery of a clinically effective treatment for NAIT. Increased use and cost-effectiveness could be achieved by the delivery of an educational programme to neonatal unit clinical staff to increase the awareness and appropriate treatment of NAIT.

Favourable outcome for patients with myeloid disorders treated with fludarabine-melphalan reduced-intensity conditioning and allogeneic bone marrow stem cell transplantation without the use of T-lymphocyte-depleting antibodies

We report the use of reduced-intensity conditioning (RIC)-matched sibling allogeneic bone marrow stem cell transplantation as a method of establishing a graft-vs.-leukaemia (GvL) effect against myeloid disorders using a fludarabine-melphalan protocol without the use of T-lymphocyte-depleting antibodies. The 16 patients in this group had predominantly poor-risk acute myeloid leukaemia (AML) (n=10), AML/myelodysplasia (MDS) (n=2) and MDS (n=4). All but one patient achieved full haematopoietic engraftment. Thirteen of 16 patients are alive and in continued complete remission on completion of this study with a median follow-up of 426 d (range 83-1524). The actuarial 4 yr disease-free and overall survival is 79% for both. Only one patient relapsed following transplant, giving a relapse rate of 6% during the study period. The treatment-related mortality was 13% (n= 2). Overall, acute graft-vs.-host disease (GvHD) occurred in 53% (8/15), with acute GvHD grade II or above occurring in 47% (7/15). In the 13 evaluable patients, chronic GvHD occurred in 46% (6/13), with this being extensive in three patients. These results suggest that a GvL effect can be delivered against poor-risk myeloid disorders with a low non-relapse mortality using this fludarabine-melphalan RIC protocol.

Modulation of interleukin-6 expression in Hodgkin and Reed-Sternberg cells by Epstein-Barr virus

Variable proportions of Hodgkin's disease (HD) cases are associated with the Epstein-Barr virus (EBV), but the role of EBV in HD is not entirely clear. Hodgkin and Reed-Sternberg (HRS) cells of EBV-associated HD are characterized by expression of the EBV gene product LMP1. In other cellular environments, LMP1 has been shown to induce interleukin (IL)-6. In this study, 105 HD cases were tested for differences in IL-6 expression among LMP1-positive and -negative cases. Isotopic in situ hybridization and correlation with the presence of EBV gene products revealed significantly higher proportions of cases with IL-6-expressing tumour cells in LMP1-positive (31 of 37, 84 per cent) as compared with LMP1-negative HD cases (35 of 68, 51 per cent). Thus, although not exclusive to EBV-positive HRS cells, IL-6 expression appears to be upregulated in EBV-associated HD. IL-6 receptor (CD126) expression was tested by in situ hybridization and found in a broad spectrum of cell types, regularly including HRS cells. Superinduction of IL-6 expression may be among the mechanisms by which EBV confers a growth advantage on virus-infected HRS cells and by which the virus may contribute to the morphological and clinical peculiarities of HD.

Frequent expression of interleukin-10 by Epstein-Barr virus-harboring tumor cells of Hodgkin's disease

Tumor cells of Epstein-Barr virus (EBV)-associated Hodgkin's disease (HD) express the viral protein, latent infection membrane protein-1 (LMP1), but evade cytotoxic responses normally directed at this antigen. We tested whether local production of the immunoregulatory interleukins (IL)-4 and -10 may have a role in this process. IL-4 RNA was not detectable in any of the HD cases. By contrast, isotopic in situ hybridization and correlation with the presence of EBV gene products showed significantly higher proportions of cases with IL-10 expressing tumor cells in LMP1-positive (17 of 26, 66%) as compared with LMP1-negative HD cases (six of 37, 16%). Absence of EBV BCRF1 RNA indicated that the transcripts originated from the cellular IL-10 gene. Similarly, an association between IL-10 expression and EBV-infection of tumor cells was found in AIDS-related malignant non-Hodgkin lymphomas (ARL). Very small proportions of EBV-infected cells, mainly blasts, expressed IL-10 in infectious mononucleosis tonsils. Thus, although not entirely exclusive to EBV-positive cases, IL-10 expression is frequently associated with EBV-infection in HD and ARL and appears to be upregulated by EBV, most likely through LMP1. In view of the established inhibitory effects of IL-10 on cell mediated immunity, it is suggested that IL-10 expression may contribute to evasion of LMP1-positive cells from cytotoxicity directed at viral antigens.

Lymphotoxin, tumour necrosis factor and interleukin-6 gene transcripts are present in Hodgkin and Reed-Sternberg cells of most Hodgkin's disease cases

Tissue specimens from 26 cases of Hodgkin's disease (HD) and six HD-derived cell lines were analysed for tumour necrosis factor (TNF), lymphotoxin (LT), and interleukin (IL)-6 RNA transcripts by in situ hybridization, in some cases subsequent to immunohistology for CD30 antigen. LT and TNF transcripts were found in tumour cells of all cases; IL-6 gene transcripts were detectable in 19/23 cases. Presence of RNA specific for these cytokines was not correlated with any of the following parameters: sex, symptoms and histotype, as well as immunophenotype and association of the tumour cells with Epstein-Barr virus. Rather, the presence of LT, TNF and IL-6 transcripts appeared to characterize Hodgkin and Reed-Sternberg cells in general, supporting concepts which suggest that HD represents a malignancy of cytokine secreting activated cells, and that many of the features distinguishing HD from other malignant lymphomas may ultimately be due to expression of cytokines. LT and TNF RNA transcripts were also found in five HD-derived cell lines, whereas supernatants of these cell lines contained high levels of LT, but low or undetectable levels of TNF activity. This suggests that, although not detectable at the level of RNA transcripts, differences between HD cases may exist on the level of cytokine gene transcript processing, translation and polypeptide secretion.