Systemic therapy in pancreatic ductal adenocarcinomas (PDACs)-basis and current status

A major shift in the approach to the management of pancreatic ductal adenocarcinomas (PDACs) has been the recognition of the systemic nature of the disease even in clinically and radiologically limited disease stages. The recalcitrant nature of PDAC is intrinsically related to the lack of therapeutic targets and dense surrounding stroma that limits the activity of currently available chemotherapeutic options. However, research is increasingly focusing on intensifying systemic management options in PDAC, resulting in gradual improvements in survival. Currently effective chemotherapeutic regimens like modified 5-fluorouracil-leucovorin-irinotecan-oxaliplatin and gemcitabine-nab-paclitaxel have improved outcomes in resectable and advanced PDAC. An increasing use of these regimens has also resulted in greater conversion of borderline resectable and locally advanced cancers to resection, though the most effective approach in this subgroup is yet to be identified. The current review presents an outline of the basic systemic nature of PDAC and current options of systemic therapy, predominantly chemotherapy .

Practice Patterns and Survival in Patients with Resected Pancreatic Ductal Adenocarcinomas (PDAC) - Results from the Multicentre Indian Pancreatic & Periampullary Adenocarcinoma Project (MIPPAP) Study

BACKGROUND

There is limited data from India with regard to presentation, practice patterns and survivals in resected pancreatic ductal adenocarcinomas (PDACs).

METHODS

The Multicentre Indian Pancreatic & Periampullary Adenocarcinoma Project (MIPPAP) included data from 8 major academic institutions across India and presents the outcomes in upfront resected PDACs from January 2015 to June 2019.

RESULTS

Of 288 patients, R0 resection was achieved in 81% and adjuvant therapy was administered in 75% of patients. With a median follow-up of 42 months (95% CI: 39-45), median DFS for the entire cohort was 39 months (95% CI: 25.4-52.5), and median overall survival (OS) was 45 months (95% CI: 32.3-57.7). A separate analysis was done in which patients were divided into 3 groups: (a) those with stage I and absent PNI (SI&PNI-), (b) those with either stage II/III OR presence of PNI (SII/III/PNI+), and (c) those with stage II/III AND presence of PNI (SII/III&PNI+). The DFS was significantly lesser in patients with SII/III&PNI+ (median 25, 95% CI: 14.1-35.9 months), compared to SII/III/PNI + (median 40, 95% CI: 24-55 months) and SI&PNI- (median, not reached) (p = 0.036)).

CONCLUSIONS

The MIPPAP study shows that resectable PDACs in India have survivals at par with previously published data. Adjuvant therapy was administered in 75% patients. Adjuvant radiotherapy does not seem to add to survival after R0 resection.

Practice Patterns and Incidence of Febrile Neutropenia in Patients Receiving Triplet Drug Chemotherapeutic Regimens in GUT Cancers: Do We Need to Add WBC Growth Factors? (ForGeT GCSF Study)

Background and Objectives: There are limited data on the requirement and duration of white blood cell (WBC) growth factor (GF) administration in patients receiving biweekly docetaxel, oxaliplatin, leucovorin, 5 Fluorouracil (mFLOT) or modified FOLFIRINOX (oxaliplatin, irinotecan, leucovorin, 5 Fluorouracil (mFOLFIRINOX) regimens.

Methods: The data of 749 patients with pancreatic, gastric, and colorectal adenocarcinomas treated with mFOLFIRINOX or mFLOT for at least three cycles between January 2018 and December 2022 were retrieved.

Results: Of the 749 patients, 387 (52%) received mFLOT, while 362 (48%) received mFOLFIRINOX. Increased use of GF was seen in patients with diabetes mellitus (70 vs. 53%; p < 0.001), prior chemotherapy (82 vs. 49%; p < 0.001), prior pelvic radiotherapy (89 vs. 54%; p < 0.001), prior surgery (70 vs. 49%; p < 0.001), and stage I to III cancers as opposed to stage IV cancers (61 vs. 48%; p = 0.006). The use of GF resulted in a statistically lesser incidence of all-grades neutropenia (2.6 vs. 18.4%; p < 0.001), grade 3/4 neutropenia (1.2 vs. 12.5%; p < 0.001), and the primary endpoint of febrile neutropenia (FN; 1.2 vs. 6.1%; p = 0.001). There were no differences in the incidence of all grades of neutropenia (3.7 vs. 1.9%; p = 0.527), grade 3/4 neutropenia, and the primary endpoint of FN (1.2 vs. 1.1%; p = 0.079) in patients receiving single-day versus multiday GF, respectively.

Interpretation and Conclusion: The use of GF reduces the rates of FN by approximately 80% in patients receiving mFLOT and mFOLFIRINOX, although incidences of FN are low with these regimens. The incidence of febrile neutropenia was similar with single-dose versus multiday GF in efficacy when administered with mFLOT and mFOLFIRINOX chemotherapy.

Real-World Evidence for Comparative Outcomes between Innovator and Biosimilar Bevacizumab in Advanced Colorectal Cancers

PURPOSE

Generic versions of bevacizumab are commonly used in India in patients with advanced/metastatic colorectal cancers (mCRCs), but there is limited real-world evidence (RWE) about their efficacy in comparison to the innovator bevacizumab.

METHODS

Patients diagnosed with mCRC between January 2017 and January 2022 and receiving a combination of chemotherapy and bevacizumab were retrospectively analyzed for demographic variables and survivals. The primary endpoint of the study was the estimation and comparison of median progression-free survival (mPFS) between patients receiving innovator versus generic bevacizumab as first-line therapy (CT1) by the Kaplan-Meier method.

RESULTS

A total of 944 patients were included in the analysis, of whom 652 patients (69%) received bevacizumab as CT1, 449 patients (48%) during second-line chemotherapy (CT2), and 74 patients (8%) during third-line therapy (CT3). The innovator was administered to 132 patients (14%), while the remaining 812 patients (86%) received a generic molecule. With a median follow-up of 18 months, there was no difference in mPFS between patients receiving the innovator or biosimilar (10 vs. 9.3 months, p  = 0.62). Similarly, there was no difference in median overall survival (mOS) between patients receiving the innovator or biosimilar during CT1 (17.8 vs. 18 months, p  = 0.85). Among the patients who received bevacizumab during CT2, there was no statistically significant difference in mPFS between the innovator and the biosimilar (5.5 vs. 5.8 months, p  = 0.97), nor was there a difference in mOS between patients receiving the innovator or biosimilar during CT2 (8.15 vs. 8.58 months, p  = 0.16).

CONCLUSION

The current study offers RWE to suggest similar outcomes with innovator and generic bevacizumab when combined with chemotherapy in mCRCs. This has significant implications in India and other low- and middle-income countries besides providing oncologists with greater confidence to use these molecules in their clinical practice.

The use of immune checkpoint inhibitors in advanced gastric/gastroesophageal adenocarcinomas - real-world evidence and the use of alternative dosing

BACKGROUND

Immune check point inhibitors (ICIs) have an established role in Microsatellite-Instability-High (MSI-H) and Combined Positive Score (CPS) high advanced gastric/gastroesophageal (G/GE) adenocarcinomas, but there is limited real world data with regard to practice patterns, and efficacy of standard doses (SD-ICIs) and alternative lower doses (LD-ICIs).

METHODS

A retrospective study of patients with advanced G/GE adenocarcinomas receiving ICIs was conducted. The primary endpoint of the study was 12-month overall survival (OS), which was computed by Kaplan-Meier method.

RESULTS

A total of 91 patients were available for analysis during the study period. Seventy-four patients (81%) received nivolumab, while the remaining received pembrolizumab. Fifteen patients (16%) had MSI-H status and had a 12-month OS of 60% and median OS of 15 months (median follow-up - 38.3 months). In the Microsatellite-Stable (MSS) cohort (84%; n = 76), ICIs (combined with chemotherapy) were used predominantly in pre-treated patients (54%; n = 41). Patients with CPS ≥5 (72%; n = 55) had improved survival compared to patients with CPS <5 (28%; n = 21) (12-month OS: 52% vs. 26%; Median OS: 12.8 months vs. 3.2 months; p = 0.005). There was no difference in survival between patients who received SD-ICIs (54%; n = 41) and LD-ICIs (46%; n = 35) (12-month OS: 42% vs. 48%; Median OS: 8.7 months vs. 11 months; p = 0.44).

CONCLUSIONS

Patients with advanced G/GEJ adenocarcinomas in the real world predominantly received ICIs during later lines of therapy as opposed to first line therapy. Using a CPS cutoff of ≥5 as opposed to CPS <5 predicts for improved survivals in MSS patients and patients receiving low dose ICIs have similar survival outcomes to patients receiving standard dose ICIs within the confines of a heterogenous study cohort.

Gemcitabine Cisplatin and Durvalumab Experience in Advanced Biliary Tract Cancers: A Real-World, Multicentric Data From India

PURPOSE

Biliary tract cancers (BTCs) are usually diagnosed in advanced stages, where treatment options are either palliative chemotherapy and/or best supportive care. The breakthrough results of the TOPAZ-1 trial demonstrated a 24% decrease in risk of death at 2 years with the addition of durvalumab to chemotherapy.

MATERIALS AND METHODS

This was a multicenter retrospective cohort study conducted across 14 institutions in India. All the patients were diagnosed with advanced BTCs. The primary objective was to assess median overall survival (mOS) with the use of durvalumab in combination with chemotherapy backbone. The patient details, treatment details, laboratory results, and outcome parameters were recorded from the prospectively collected databases.

RESULTS

A total of 148 patients were included with a median age of 57.5 years; 36 (24.3%) patients had borderline Eastern Cooperative Oncology Group performance status ≥2. The most common subtype was gall bladder cancer (GBC), seen in 94 patients (63.5%); 126 (85.1%) patients presented with de novo metastases. At a median follow-up of 6.8 months (95% CI, 5.9 to 7.8), the estimated mOS for the entire cohort was 12 months (95% CI, 7.8 to 16.3) and median progression-free survival was 8.2 months (95% CI, 7.1 to 9.4) with objective response achieved in 44 (29.7%) patients, and the estimated 2-year OS being 25%. Immune-related grade 3/4 adverse events were reported in 11 (7.4%) patients. In multivariate analysis, age <60 years (P = .001) and standard dose of durvalumab (P < .001) were found to have improved OS compared with age >60 years and low dose of durvalumab.

CONCLUSION

To our knowledge, these real-world data provide the first evidence in Indian context of the efficacy and safety of durvalumab plus chemotherapy in patients with advanced/metastatic BTCs especially in GBC.

Non-operative management in low-lying rectal cancers undergoing chemoradiation

PURPOSE

To evaluate the outcomes of post-neoadjuvant chemoradiation (NACTRT) wait-and-watch Strategy (WWS) in distal rectal cancers.

MATERIALS AND METHODS

All consecutive patients from December 2012 to 2019 diagnosed with distal rectal tumors (T2-T4 N0-N+) having a complete or near-complete response (cCR or nCR, respectively) post-NACTRT and wishing for the non-surgical treatment option of WWS were included in this study. Patients were observed with 3 monthly magnetic resonance imaging (MRIs), sigmoidoscopies, and digital rectal examination for 2 years and 6 monthly thereafter. Organ preservation rate (OPR), local regrowth rate (LRR), non-regrowth recurrence-free survival (NR-RFS) and overall survival (OAS) were estimated using the Kaplan-Meier method, and factors associated with LRR were identified on univariate and multivariate analysis using the log-rank test (P < 0.05 significant).

RESULTS

Sixty-one consecutive patients post-NACTRT achieving cCR[44 (72%)] and nCR[17 (28%)], respectively, were identified. All patients received pelvic radiotherapy at a dose of 45-50Gy conventional fractionation and concurrent capecitabine. An additional boost dose with either an external beam or brachytherapy was given to 39 patients. At a median follow-up of 39 months, 11 (18%) patients had local regrowth, of which seven were salvaged with surgery and the rest are alive with the disease, as they refused surgery. The overall OPR, NR-RFS, and OS were 83%, 95%, and 98%, respectively. Seven (11%) patients developed distant metastasis, of which six underwent metastatectomy and are alive and well. LRR was higher in patients with nCR versus cCR (P = 0.05).

CONCLUSION

The WWS is a safe non-operative alternative management for selected patients attaining cCR/nCR after NACTRT with excellent outcomes.

Modified FOLFIRINOX (mFOLFIRINOX) as neoadjuvant therapy and 'salvage' in patients with high risk locally advanced rectal cancers - tolerance and early outcomes

BACKGROUND

There is limited data with regard to the use of modified 5-fluoroural-leucovorin-irinotecan-oxaliplatin (mFOLFIRINOX) in terms of tolerance and enabling total mesorectal excision (TME) of locally advanced rectal adenocarcinomas (LARC) with high-risk characteristics (T4b status, signet ring histology etc) post standard neoadjuvant long course chemoradiation (NACTRT) or short course radiation (SCRT) and chemotherapy.

MATERIALS AND METHODS

Patients with LARC from January 2018 to December 2020 receiving mFOLFIRINOX post NACTRT/SCRT to facilitate TME were evaluated. The primary endpoint was assessment of grade 3 and grade 4 treatment related toxicity and TME rates. Event free survival (EFS), where event was defined as disease progression or recurrence post resection after mFOLFIRINOX, was calculated by Kaplan Meier method.

RESULTS

Forty-seven patients were evaluated with a median age of 33 years (Range:18-59), 45% T4b status, 96% radiological circumferential margin (CRM) involved (79% CRM positive post NACTRT/SCRT), 43% extramural venous invasion (n=33) and 36% signet ring histology. 62% had received prior NACTRT and 38% had received SCRT with chemotherapy before receiving mFOLFIRINOX. The most common grade 3 and grade 4 treatment related side effects included diarrhoea (7%), anaemia (4%) and infections (4%). Intended duration of mFOLFIRINOX or beyond was completed in 94% of patients. 60% of patients underwent curative local resection with R0 resection rates of 100% (n=28) and pathological complete response rates of 21%. The most common surgeries done were exenterations and abdominoperineal in 22% and 17% patients respectively. With a median follow up of 19 months, 24 patients had recurred or progressed for a median EFS of 20 months [95% confidence interval (CI): 15-24].

CONCLUSIONS

Locally advanced rectal cancers with high-risk characteristics are a niche group of cancers with less-than-optimal outcomes post standard neoadjuvant strategies. mFOLFIRINOX appears to be well tolerated and enables TME in a significant proportion of these patients.

MRI in rectal cancer patients on 'watch and wait': patterns of response and their evolution

PURPOSE

Evaluate MR patterns of response and their evolution in rectal cancer patients on watch and wait (WW).

METHODS

We retrospectively reviewed 337 MRIs of 60 patients (median follow-up: 12 months; range: 6-49 months). Baseline MRIs (available in 34/60 patients) were evaluated for tumor morphology, location, thickness, circumferential involvement, nodal status and EMVI. First post-treatment MRIs (in all patients) were additionally evaluated for pattern of response on T2 and DWI. Change in post-treatment scar thickness and scar depth angle between the first and second post-treatment scans was also evaluated. Evolution of the response pattern/recurrence were evaluated till the last available scan.

RESULTS

On the baseline scans, 20/34 (59%) patients had polypoidal tumor with 12/20 having ≤ 25% circumferential wall involvement. We saw five patterns of response-normalized rectal wall (2/60-3%), minimal fibrosis (23/60-38%), full thickness fibrosis (16/60-27%), irregular fibrosis (11/60-18%) and split scar (6/60-10%), with 2/60 (3%) showing possible residual disease. On the first post-treatment scans, 12/60 (20%) had restricted diffusion, with 3/12 having persistent restriction till last follow-up. Post-treatment fibrosis/split scar remained stable in 44/60 (73%) cases and improved further in the rest. 9/60 (15%) patients developed regrowth/recurrence. Patients with recurrence had < 10 mm scar thickness and < 21° change in scar angle between the first and second post-treatment MRIs.

CONCLUSION

Most patients on WW protocol developed minimal or full thickness fibrosis, majority of which remained stable on follow-up.

A randomized phase II/III trial of rosuvastatin with neoadjuvant chemo-radiation in patients with locally advanced rectal cancer

Aim

Statins have been shown to improve the possibility of a pathological complete response (pCR) in patients with locally advanced rectal cancer when given in combination with neo-adjuvant chemo-radiation (NACTRT) in observational studies. The primary objective of this phase II randomized controlled trial (RCT) is to determine the impact of rosuvastatin in improving pCR rates in patients with locally advanced rectal cancer who are undergoing NACTRT. The secondary objectives are to compare adverse events, postoperative morbidity and mortality, disease-free survival (DFS), and overall survival in the two arms and to identify potential prognostic and predictive factors determining outcomes. If the study is positive, we plan to proceed to a phase III RCT with 3-year DFS as the primary endpoint.

Methods

This is a prospective, randomized, open-label phase II/III study. The phase II study has a sample size of 316 patients (158 in each arm) to be accrued over 3 years to have 288 evaluable patients. The standard arm will receive NACTRT while the intervention group will receive 20 mg rosuvastatin orally once daily along with NACTRT for 6 weeks followed by rosuvastatin alone for 6-10 weeks until surgery. All patients will be reviewed after repeat imaging by a multidisciplinary tumor board at 12-16 weeks after starting NACTRT and operable patients will be planned for surgery. The pathological response rate, tumor regression grade (TRG), and post-surgical complications will be recorded.

Conclusion

The addition of rosuvastatin to NACTRT may improve the oncological outcomes by increasing the likelihood of pCR in patients with locally advanced rectal cancer undergoing NACTRT. This would be a low-cost, low-risk intervention that could potentially lead to the refinement of strategies, such as "watch and wait", in a select subgroup of patients.

Clinical trial registration

Clinical Trials Registry of India, identifier CTRI/2018/11/016459.

Factors Predicting Prognosis in Metastatic Grade 1 Gastro-entero-pancreatic Neuroendocrine Tumors

INTRODUCTION

The incidence of gastroenteropancreatic neuroendocrine tumors (GEP-NET) has steadily increased. These tumors are considered relatively indolent even when metastatic. What determines survival outcomes in such situations is understudied.

MATERIALS AND METHODS

Retrospective analysis of a prospectively maintained NET clinic database, to include patients of metastatic grade 1 GEP-NET, from January 2018 to December 2021, to assess factors affecting progression-free survival (PFS).

RESULTS

Of the 589 patients of GEP-NET treated during the study period, 100 were grade 1, with radiological evidence of distant metastasis. The median age was 50 years, with 67% being men. Of these, 15 patients were observed, while 85 patients received treatment in the form of surgery (n = 32), peptide receptor radionuclide therapy (n = 50), octreotide LAR (n = 22), and/or chemotherapy (n = 4), either as a single modality or multi-modality treatment. The median (PFS) was 54.5 months. The estimated 3-year PFS and 3-year overall survival rates were 72.3% (SE 0.048) and 93.4% (SE 0.026), respectively. On Cox regression, a high liver tumor burden was the only independent predictor of PFS (OR 3.443, p = 0.014). The 5-year OS of patients with concomitant extra-hepatic disease was significantly lower than that of patients with liver-limited disease (70.7% vs. 100%, p = 0.017).

CONCLUSION

A higher burden of liver disease is associated with shorter PFS in patients with metastatic grade I GEP-NETs. The OS is significantly lower in patients with associated extrahepatic involvement. These parameters may justify a more aggressive treatment approach in metastatic grade 1 GEP-NETs.

1657 Resected Gastric Adenocarcinomas at a Single Institution: Outcomes and Trends over 17 Years

BACKGROUND

Outside of clinical trials, real-world data of advanced gastric cancers (AGCs) managed with perioperative or adjuvant chemotherapy with a backbone of D2 lymphadenectomy is limited.

PATIENTS AND METHODS

Curative resections for gastric adenocarcinoma between January 2003 and January 2020 at the Tata Memorial Centre were analyzed, comparing three time periods marking major increments in annual gastric resections (GRs).

RESULTS

1657 radical gastric resections were performed with a morbidity and mortality rate of 34.9% and 1.4%, respectively. Over three consecutive periods, the number of annual GRs increased from 56/year to 97/year to 156/year (P < 0.001) with a significant escalation in surgical magnitude and complexity. Improvement in surgical quality indicators (median lymph node yield from 15 to 25, P < 0.001 and margin negativity from 8.2 to 5.5%, P = 0.002) was observed with no corresponding increase in severe complications (6.9%) or mortality (1.4%). The proportion of distal and signet ring cancers was found to decrease over time, with an increase in proximal cancers and younger age at presentation. Overall, 90% of GRs were for AGCs with a median overall survival (OS) of 4.4 years (± 6 months), and 5-year OS rate of 47.6% (± 1.9%).

CONCLUSIONS

Change in pattern of tumor characteristics was observed. Aggressive treatment options for AGC were employed progressively with excellent survival. With increase in volumes, improvements in surgical quality indicators, and a relative improvement in postoperative mortality was observed. These results provide a roadmap for developing dedicated gastric cancer centers.

Gastrointestinal Stromal Tumor – An Overview

Gastrointestinal stromal tumors (GISTs) are rare tumors but are most common mesenchymal tumors of the digestive tract. They are commonly seen in the stomach (60%) and small intestine (30%). GISTs are likely derived from the interstitial cells of Cajal or their stem cell precursors. They are best characterized by computerized tomography and have a specific staining pattern on immunohistochemistry, i.e., C-Kit and DOG-1. The treatment of GIST is based on the risk assessment for relapse, and patients with localized GIST require resection with or without adjuvant imatinib mesylate (IM). Advanced unresectable tumors are usually treated with IM, with a number of further options available for patients post progression on IM. There is an increasing emphasis on identifying C-Kit and platelet-derived growth factor receptor alpha mutations in all patients with GIST, as these are driver mutations with current and future therapeutic implications.

Preventing futile surgery in Intrahepatic and Perihilar cholangiocarcinomas: Can we identify preoperative factors to improve patient selection and optimize outcomes?

BACKGROUND

Intraoperative unresectability, postoperative deaths and early recurrences remain devastating futile events in the surgical management of Intrahepatic cholangiocarcinomas (iCCA) and Perihilar cholangiocarcinomas (pCCA). The present study aims to determine the preoperative predictors of futile surgery in cholangiocarcinomas.

METHODS

Consecutive hepatectomies for iCCA and pCCA, between September 2010 and June 2022 were included. Futility of surgery was defined as either intraoperative unresectability, postoperative 30-day mortality or recurrence within six months of surgery. Multivariable logistic regression was used to identify predictors of futility.

RESULTS

One hundred and fifty patients of iCCA and pCCA underwent surgery during the time period. Thirty-seven (38.1 %) out of 97 patients of iCCA and 25(47.16 %) out of 53 patients of pCCA underwent futile resection. The predictive factors of futile surgery for iCCA were tumour number (≥2) (OR, 9.705; 95%CI, 2.378-39.614; p = 0.002), serum aspartate transaminase (OR, 8.31; 95%CI, 2.796-24.703; p < 0.001) and serum CA-19.9 (>37 U/ml) (OR, 2.95; 95%CI, 1.051-8.283; p = 0.04). The predictive factors of futility for pCCA were lymph node involvement (OR, 7.636; 95%CI, 1.824-31.979; p = 0.005) and serum alkaline phosphatase (>562.5 U/L) (OR, 11.211; 95%CI, 1.752-71.750; p = 0.011).

CONCLUSION

Futile surgery was observed in over one third of our patients. Five strong preoperative predictors of futility were identified. Careful analysis of these factors may reduce futile surgical explorations.

Treatment practices for metastatic pancreatic cancer: Can we deliver an appropriately efficacious and safe regimen in Indian patients?

INTRODUCTION

The median overall survival (mOS) in metastatic pancreatic cancers (PCs) hovers between 6 months to 11 months.

MATERIALS AND METHODS

The study is a retrospective analysis of metastatic PC patients who were evaluated from August 2013 to August 2016 in the Department of Gastrointestinal (GI) Medical Oncology, Tata Memorial Hospital (TMH).

RESULTS

Out of 218 patients, 24 patients (11%) were not planned for chemotherapy and referred to the Department of Palliative Care for further supportive care. One hundred and fifty-three patients received palliative chemotherapy in TMH with median age of 56 years (range: 23-79), male (60.1%), and nonresident in Maharashtra (60.1%). Regimens used most commonly were gemcitabine-nab-paclitaxel in 60 patients (39.2%), gemcitabine-erlotinib in 25 patients (16.3%), and modified FOLFIRINOX in 21 patients (13.7%). A total of 58 patients (43%; n = 135) had Grade 3/4 toxicities. As of cutoff date for the analysis of outcomes, 139 patients (90.8%) patients had ceased first-line chemotherapy, due to radiologically proven progressive disease (PD) in 89 patients (64%), repeated Grades 3 and 4 adverse events in 26 patients (18.7%), and clinically PD in 18 patients (12.9%). With a median follow-up of 278 days, the mOS was 217 days (95% confidence interval [CI]: 175-258), and the median event-free survival was 125 days (95% CI: 107-122).

CONCLUSION

Dose modifications for chemotherapy are required commonly when treating metastatic PC, with common reasons for dose reduction being toxicities, Eastern Cooperative Oncology Group performance status >=2, and low albumin levels. Studies evaluating logistic and financial aspects of treating metastatic PC with chemotherapy in India are warranted.

Performance of Low-Dose Immunotherapy and Standard-Dose Immunotherapy in Microsatellite Instability-High Metastatic Colorectal Cancer: Real-World Data (CLouD-High Study)

PURPOSE

Standard-dose immune checkpoint inhibitors (SD-ICIs) are the standard of care as initial therapy in microsatellite instable-high (MSI-H) advanced/metastatic colorectal adenocarcinomas (mCRC), but there are preclinical data to suggest that low-dose ICIs (LD-ICI) might also have similar efficacy.

MATERIALS AND METHODS

A retrospective study of patients with MSI-H mCRC receiving ICIs between June 2017 and January 2023 was conducted. The primary end point of the study was 12-month progression-free survival (PFS), which was computed using the Kaplan-Meier method.

RESULTS

A total of 65 patients were available for analysis during the study period. Sixty patients (92%) received nivolumab, whereas the remaining received pembrolizumab. First-line ICIs were received by 18 patients (28%), whereas 47 patients (72%) received ICIs during later lines. Thirty patients (47%) received LD-ICIs (all received nivolumab), with the remaining receiving SD-ICIs (53%). At a median follow-up of 16.5 (95% CI, 11.8 to 21.2) months, median PFS was not reached in the entire cohort. The 12-month PFS rate in the LD-ICI cohort was 90%, whereas it was 75.8% in the SD-ICI cohort. There were no statistical differences in patients receiving ICIs as first-line therapy (12 months PFS-94.4%) or during later lines of therapy (12-month PFS-77.9%; P = .56).

CONCLUSION

ICIs in the current study show survivals which are similar to those seen in seminal trials in patients with MSI-H mCRC. Low-dose ICIs appear to work in MSI-H mCRC and should be explored prospectively in clinical trials. Patients with MSI-H status should be exposed to ICIs, whether initially or later during treatment, whenever feasible.

Tata Memorial Centre Evidence Based Management of Colorectal cancer

This review article examines the evidence-based management of colorectal cancers, focusing on topics characterized by ongoing debates and evolving evidence. To contribute to the scientific discourse, we intentionally exclude subjects with established guidelines, concentrating instead on areas where the current understanding is dynamic. Our analysis encompasses a thorough exploration of critical themes, including the evidence surrounding complete mesocolic excision and D3 lymphadenectomy in colon cancers. Additionally, we delve into the evolving landscape of perioperative chemotherapy in both colon and rectal cancers, considering its nuanced role in the context of contemporary treatment strategies. Advancements in surgical techniques are a pivotal aspect of our discussion, with an emphasis on the utilization of minimally invasive approaches such as laparoscopy and robotic surgery in both colon and rectal cancers, including advanced rectal cases. Moving beyond conventional radical procedures, we scrutinize the feasibility and implications of endoscopic resections for small tumors, explore the paradigm of organ preservation in locally advanced rectal cancers, and assess the utility of total neoadjuvant therapy in the current treatment landscape. Our final segment reviews pivotal trials that have significantly influenced the management of colorectal liver and peritoneal metastasis.

Prognostic Significance of EMVI in Rectal Cancer in a Tertiary Cancer Hospital in India

Background  Presence of extramural venous invasion (EMVI) is a poor prognostic factor for rectal cancer as per literature. However, India-specific data are lacking. Aim  The aim of the study is to determine the prognostic significance of EMVI in locally advanced rectal cancer on baseline MRI. Materials and Methods  We retrospectively reviewed 117 MRIs of operable non-metastatic locally advanced rectal cancers in a tertiary cancer institute. Three dedicated oncoradiologists determined presence or absence of EMVI, and its length and thickness, in consensus. These patients were treated as per standard institutional protocols and followed up for a median period of 37 months (range: 2-71 months). Kaplan-Meier curves (95% CI) were used to determine disease-free survival (DFS), distant-metastases free survival (DMFS), and overall survival (OS). Univariate analysis was performed by comparing groups with log-rank test. Results  EMVI positive cases were 34/114 (29%). More EMVI-positive cases developed distant metastasis compared with EMVI-negative cases (14/34-41% vs. 22/83-26%). The difference, however, was not statistically significant ( p  = 0.146). After excluding signet-ring cell cancers ( n  = 14), EMVI showed significant correlation with DMFS ( p  = 0.046), but not with DFS or OS. The median thickness and length of EMVI was 6 and 14 mm, respectively in patients who developed distant metastasis, as compared with 5 and 11 mm in those who did not, although this difference was not statistically significant. Conclusion  EMVI is a predictor of distant metastasis in locally advanced non-metastatic, non-signet ring cell rectal cancers. EMVI can be considered another high-risk feature to predict distant metastasis.

The Prevalence of BRAF, PIK3CA, and RAS Mutations in Indian Patients with Colorectal Cancer

Omshree ShettyVikas OstwalIntroduction  The present study evaluates the mutation pattern and frequency of BRAF , PIK3CA and RAS in colorectal carcinoma observed in the tertiary cancer center in India. Materials and Methods  Consecutive cases of colorectal adenocarcinoma ( n  = 330) registered from January 2015 to December 2019 (5-year duration) were selected for the study. Molecular analysis for BRAF . PIK3CA (exon 9 and 20) and RAS ( KRAS & NRAS ) was performed on representative formalin-fixed paraffin-embedded tissues by Sanger sequencing. Results were correlated with clinicopathological features. Patient overall survival (OS) was obtained using Kaplan-Meier method. Results  The study cohort was in the age range of 22 to 81 years (median age: 52 years) that included 202 males and 96 females (male: female ratio 2.1:1). BRAF V600E mutation was observed in three cases (1%), while 17 cases (5.7%) had mutations in the PIK3CA gene (exon 9 or exon 20). Mutation analysis for RAS gene ( KRAS & NRAS ) was observed among 42 (15.4%) cases with KRAS mutation and 11 (4%) cases were positive for NRAS mutations. Among RAS, KRAS G12D was the predominant mutation. Median OS with wild-type RAS was 46.6 months (95% confidence interval [CI]: 22.4-70.8), while for RAS mutated patients, it was 25.6 months (95% CI: 16.7-34.5), hazard ratio: 1.7 (95% CI: 1.1-2.7, p  = 0.025). Conclusion  This study evaluated the prevalence of BRAF, PIK3CA and RAS mutations in the Indian cohort and its impact on clinical behavior. There was lower incidence of BRAF mutations in this cohort and PIK3CA mutation (single) did not impact survival of the patients.

Impact of FDG PET/CT Scan in Changing Management of Well-Differentiated Neuroendocrine Tumors With Ki67 Index Less Than or Equal to 5

OBJECTIVES

This study aimed to see the impact of FDG PET/CT with somatostatin receptor PET (SSTR PET) in directing the treatment plan in lower-grade well-differentiated neuroendocrine tumors (NETs) with Ki67 index ≤5%.

METHODS

Sixty-three NET cases with Ki67 index ≤5% with both FDG PET and SSTR PET ( 68 Ga-DOTANOC PET) were included for this retrospective observational study. FDG PET findings were classified into positive, weakly positive, and negative based on a visual scale. Clinical factors considered while referring for FDG PET scan were audited from electronic medical records. The addition of chemotherapy was considered as FDG-directed change in treatment.

RESULTS

Sixty patients showed intense SSTR expression in the primary and metastatic sites (if present). Three patients showed no evidence of SSTR expression, in whom the scans were done after resection of the primary tumor. The FDG PET was positive in 25 (39.6%), weakly positive in 11 (17.4%), and negative in 27 (42.8%). Specific clinical reason for doing FDG PET was found in 34 patients, and in the remaining 29, there was no justification or specific indication for doing the FDG study; 73.5% of patients from the former group was either FDG positive or weakly positive, and 26.5% were negative; in the other group, 62.1% were FDG-negative, and 37.9% were positive ( P = 0.004). Treatment-naive patients with symptom duration of ≤5 months were associated with more FDG positivity than patients with >5 months' symptom duration ( P = 0.006). FDG PET/CT led to change in management in 17.4% of all the patients, 9.6% of grade 1, and 25% of grade 2 patients.

CONCLUSIONS

In lower-grade NET, FDG positivity was seen in a sizable number of the cases, and this led to change in management in 17.4% of the cases. Specific clinical features could be utilized to successfully discriminate between FDG-avid and non-FDG-avid disease in lower-grade NETs, and this had impact in management change as well.

Docetaxel-oxaliplatin-capecitabine/5-fluorouracil (DOX/F) followed by docetaxel versus oxaliplatin-capecitabine/5-fluorouracil (CAPOX/FOLFOX) in HER2-negative advanced gastric cancers

BACKGROUND

We evaluated whether the addition of docetaxel (D) to a combination comprising 5-fluorouracil/leucovorin (5-FU/LV) or capecitabine (C) plus oxaliplatin (O) (DOF/DOX) improved overall survival (OS) compared with 6 months of 5-fluorouracil (5-FU) or capecitabine in combination with oxaliplatin (FOLFOX/CAPOX) alone in advanced HER2-negative gastroesophageal junction and gastric adenocarcinomas (G/GEJ).

METHODS

This study was an investigator-initiated, open-label, multi-institutional, randomized phase III trial in adult patients with HER2-negative advanced G/GEJs. The primary endpoint of the study was a comparison of median OS by Kaplan-Meier method. Next-generation sequencing was performed on tissue.

RESULTS

Of the 324 patients randomly assigned between July 2020 and November 2022, 305 patients were evaluable for analysis (FOLFOX/CAPOX: 156; DOF/DOX: 149). With a median follow-up time of 19.2 months (95% Confidence Interval [CI] = 16.5 months to 21.9 months) for the entire cohort, the median OS was 10.1 months (95% CI = 9.2 to 10.9) for FOLFOX/CAPOX and 8.9 months (95% CI = 7.3 to 10.5) for DOF/DOX, and this difference was not statistically significant (P = .70). An increased proportion of grade 3 or grade 4 neutropenia (21% vs 3%; P < .001) and grade 2/3 neuropathy (17% vs 7%; P = .005) was seen in patients receiving DOF/DOX. Genomic profiling revealed a low incidence of microsatellite instability (1%) and a high incidence of BRCA1 (8.4%) and BRCA2 (7.5%) somatic alterations.

CONCLUSION

FOLFOX or CAPOX chemotherapy for 6 months remains one of the standards of care in advanced HER2-negative gastroesophageal junction and gastric adenocarcinomas, with no additional survival benefit seen with the addition of docetaxel. Genomic profiling of patients revealed a higher than previously known incidence of somatic BRCA alterations, which requires further evaluation.CTRI (Clinical Trial Registry of India: CTRI/2020/03/023944).