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.

Emerging predictive biomarkers for novel therapeutics in peripheral T-cell and natural killer/T-cell lymphoma.

Peripheral T-cell lymphoma (PTCL) and natural killer/T-cell lymphoma (NKTCL) are rare subtypes of non-Hodgkin's lymphoma that are typically associated with poor treatment outcomes. Contemporary first-line treatment strategies generally involve the use of combination chemoimmunotherapy, radiation and/or stem cell transplant. Salvage options incorporate a number of novel agents including epigenetic therapies (e.g. HDAC inhibitors, DNMT inhibitors) as well as immune checkpoint inhibitors. However, validated biomarkers to select patients for individualized precision therapy are presently lacking, resulting in high treatment failure rates, unnecessary exposure to drug toxicities, and missed treatment opportunities. Recent advances in research on the tumor and microenvironmental factors of PTCL and NKTCL, including alterations in specific molecular features and immune signatures, have improved our understanding of these diseases, though several issues continue to impede progress in clinical translation. In this Review, we summarize the progress and development of the current predictive biomarker landscape, highlight potential knowledge gaps, and discuss the implications on novel therapeutics development in PTCL and NKTCL.

Effect of HIPEC on Peritoneal Recurrence in Peritoneal Metastasis Treated With Cytoreductive Surgery: A Systematic Review.

BACKGROUND: Peritoneal metastasis (PM) is a late-stage manifestation of intra-abdominal malignancies. The current standard of care indicates that cure can only be achieved with cytoreductive surgery (CRS) which is often indicated with concurrent adjuvant hyperthermic intraperitoneal chemotherapy (HIPEC). However, the utility of HIPEC within subsets of PM is not fully understood. We seek to compare the effectiveness of HIPEC in improving peritoneal recurrence rates in PM of different origins. METHODS: We conducted a systematic review of trials on the PubMed, EMBASE, and Cochrane databases, last searched in August 2021. Biases were assessed using the Cochrane Collaboration's tool for assessing the risk of bias in randomized trials as well as the Methodological Index for Non-Randomized Studies (MINORS) framework. RESULTS: 7 gastric PM studies, 3 ovarian PM studies, and 3 colorectal PM studies were included. Recurrence-free survival was improved in the HIPEC + CRS cohort in 5 gastric trials but only 1 ovarian trial and none of colorectal origin. DISCUSSION: Our findings indicate decent effectiveness of HIPEC in gastric PM, but limited utility in ovarian and colorectal PM. Limitations in the current literature are attributed to the paucity of data available, a lack of homogeneity and consideration of novel and personalised treatment regimens. We implore for further studies to be conducted with a focus on patient selection and stratification, and suggest a reframing of approach towards modern molecular and targeted therapeutic options in future studies of HIPEC. SYSTEMATIC REVIEW REGISTRATION: https://www.researchregistry.com/browse-the-registry#registryofsystematicreviewsmeta-analyses/registryofsystematicreviewsmeta-analysesdetails/60c1ffff0c1b78001e8efbe3/, identifier reviewregistry1166.

Clinical Features of Plasmablastic Lymphoma: Case Series From an Asian Tertiary Cancer Center and Literature Review.

BACKGROUND: Plasmablastic lymphoma (PBL) is an aggressive subtype of mature B-cell non-Hodgkin lymphoma. Given its rarity, there remains a lack of clinicopathological data to guide its management, particularly on Asian patients. METHODS: We conducted a retrospective chart review of 10 patients diagnosed with PBL at the National Cancer Centre Singapore and performed a literature review of similar studies on Asian cohorts. RESULTS: Most patients were male (n = 9), with median age at diagnosis of 55 years (range, 33 - 91 years). Seven (70%) patients were considered to be immunocompromised. In the overall cohort, the median overall survival (OS) was 19.4 months with 5-year survival estimates given at 60% and 36% for OS and progression-free survival (PFS), respectively. At diagnosis, patients with HIV/AIDS (n = 5) were younger compared to others (median, 43 vs. 61 years; P = 0.0278), had greater number of nodal site involvement (median, 6 vs. 0; P = 0.0333), and higher international prognostic index (IPI) scores (P = 0.034 for trend). Amongst different chemotherapy used, etoposide, prednisone, vincristine, cyclophosphamide and doxorubicin (EPOCH)-based regimens (n = 6) elicited prominent complete response rates (83%) and led to durable responses even in the setting of advanced stage, high-risk IPI score and immunodeficiency. CONCLUSIONS: In conclusion, our study describes the features of PBL in an Asian cohort and highlights disease features unique to HIV-associated PBL.