Disease-Free Survival and Time to Complete Response After Definitive Chemoradiotherapy for Squamous-Cell Carcinoma of the Anus According to HIV Infection

Brazilian Society of Surgical Oncology: Guidelines for the management of anal canal cancer

BACKGROUND

Anal canal squamous cell carcinoma (SCC) is a relatively uncommon neoplasia, and it is mostly a local-regional cancer, of low metastatic potential (only 15%), resulting in cure in most cases treated with definitive chemoradiation. On the other hand, its incidence has been steadily increasing over the last decades, which makes it an important public health problem. In an effort to provide surgeons and oncologists who treat patients with anal cancer with the most updated information based on the best scientific evidence, the Brazilian Society of Surgical Oncology (SBCO) has produced the present guideline for the management of anal canal SCC, focused on the main topics related to daily clinical practice.

OBJECTIVES

The SBCO developed the present guidelines to provide recommendations on the main topics related to the management of anal canal squamous cell carcinoma (SCC) based on current scientific evidence.

METHODS

Between October 2022 and January 2023, 14 experts met to develop the guidelines for the management of anal canal cancer. A total of 30 relevant topics were distributed among the participants. The methodological quality of a final list with 121 sources was evaluated, all the evidence was examined and revised, and the management guidelines were formulated by the 14-expert committee. To reach a final consensus, all the topics were reviewed in a meeting that was attended by all the experts.

RESULTS

The proposed guidelines contained 30 topics considered to be highly relevant in the management of anal canal cancer, covering subjects related to screening recommendations, preventive measures, tests required for diagnosing and staging, treatment strategies, response assessment after chemoradiotherapy, surgical technique-related aspects, and follow-up recommendations. In addition, screening and response assessment algorithms, and a checklist were proposed to summarize the important information and offer an updated tool to assist surgeons and oncologists who treat anal canal cancer and in providing the best care to their patients.

CONCLUSION

These guidelines summarize recommendations based on the most current scientific evidence on relevant aspects of anal canal cancer management and are a practical guide to help surgeons and oncologists who treat anal canal cancer make the best therapeutic decisions.

Accuracy and Clinical Impact of Persistent Disease Diagnosed on Diffusion-Weighted Imaging and Accuracy of Pelvic Nodal Assessment on Magnetic Resonance Imaging for Squamous Cell Carcinoma of the Anus in the 6-Month Interval Post Chemoradiotherapy

PURPOSE

To evaluate the diagnostic performance of diffusion-weighted imaging (DWI) in the 6-month interval post chemoradiation therapy (CRT) in determining persistent disease and whether persistent diffusion restriction on DWI at 6 months is associated with overall survival; and secondarily, to investigate the accuracy of pelvic lymph node assessment on T2-weighted imaging and DWI in the 6-month interval post CRT, in patients with squamous cell carcinoma of the anus.

METHODS AND MATERIALS

This retrospective study included patients with squamous cell carcinoma of the anus who underwent CRT followed by restaging rectal MRI from January 2010 to April 2020, with ≥1 year of follow-up after CRT. DW images were qualitatively evaluated by 2 junior and 2 senior abdominal radiologists to determine anal persistent disease. The reference standard for anal persistent disease was digital rectal examination/endoscopy and histopathology. Diagnostic performance was estimated using sensitivity, specificity, negative predictive value, and positive predictive value. Survival outcomes were evaluated via Kaplan-Meier analysis, and associations between survival outcomes and DWI status were tested for significance using the log-rank test. Additionally, DW and T2-weighted images were evaluated to determine lymph node status.

RESULTS

Among 84 patients (mean age, 63 ± 10.2 years; 64/84 [76%] female), 14 of 84 (17%) had confirmed persistent disease. Interreader agreement on DWI between all 4 radiologists was moderate (Light's κ = 0.553). Overall, DWI had a sensitivity of 71.4%, specificity of 72.1%, positive predictive value of 34.5%, and negative predictive value of 92.5%. Patients with a negative DWI showed better survival than patients with a positive DWI (3-year overall survival of 92% vs 79% and 5-year overall survival of 87% vs 74%), although the difference did not reach statistical significance (P = .063). All patients with suspicious lymph nodes (14/14, 100%) showed negative pathology or decreased size during follow-up.

CONCLUSIONS

At 6 months post CRT, DWI showed value in excluding anal persistent disease. Persistent diffusion restriction on DWI was not significantly associated with overall survival. Pelvic nodal assessment on DWI and T2-weighted imaging was limited in predicting persistent nodal metastases.

Machine learning and molecular simulation-based protocols to identify novel potential inhibitors for reverse transcriptase against HIV infections

Acquired immunodeficiency syndrome (AIDS) is a potentially fatal condition affecting the human immune system, which is attributed to the human immunodeficiency virus (HIV). The suppression of reverse transcriptase activity is a promising and feasible strategy for the therapeutic management of AIDS. In this study, we employed machine learning algorithms, such as support vector machines (SVM), k-nearest neighbor (k-NN), random forest (RF), and Gaussian naive base (GNB), which are fast and effective tools commonly used in drug design. For model training, we initially obtained a dataset of 5,159 compounds from BindingDB. The models were assessed using tenfold cross-validation to ensure their accuracy and reliability. Among these compounds, 1,645 compounds were labeled as active, having an IC50 below 0.49 µM, while 3,514 compounds were labeled "inactive against reverse transcriptase. Random forest achieved 86% accuracy on the train and test set among the different machine learning algorithms. Random forest model was then applied to an external ZINC dataset. Subsequently, only three hits-ZINC1359750464, ZINC1435357562, and ZINC1545719422-were selected based on the Lipinski Rule, docking score, and good interaction. The stability of these molecules was further evaluated by deploying molecular dynamics simulation and MM/GBSA, which were found to be -38.6013 ± 0.1103 kcal/mol for the Zidovudine/RT complex, -59.1761 ± 2.2926 kcal/mol for the ZINC1359750464/RT complex, -47.6292 ± 2.4206 kcal/mol for the ZINC1435357562/RT complex, and -50.7334 ± 2.5713 kcal/mol for the ZINC1545719422/RT complex.Communicated by Ramaswamy H. Sarma.

Clinicopathological Characteristics and Outcomes of Anal Squamous Cell Carcinoma Patients With and Without HIV Infection in Sub-Saharan Africa

PURPOSE

In the past 20 years, the burden of anal cancer (AC) increased by 60% in the United States and over three-fold in Africa. Rates of AC have increased by 20× in people living with HIV and the highest (50×) in men with HIV who have sex with men. However, in sub-Saharan Africa (SSA) where HIV is endemic, data on clinicopathological characteristics and outcomes of patients with AC are lacking. To address this, we have investigated AC disease presentation, treatment outcomes, and its predictors in a cohort of patients who were either HIV-infected or HIV-uninfected in SSA.

METHODS

We conducted a retrospective cohort study of patients with anal squamous cell carcinoma (SCC) treated at Ocean Road Cancer Institute in Dar es Salaam, Tanzania from January 2014 to December 2019. Associations between the study outcomes and their predictors were analyzed using univariate and multivariate analysis models.

RESULTS

A total of 59 patients with anal SCC were retrieved and had at least 2-year follow-up. The mean age was 53.9 (standard deviation ±10.5) years. While none of the patients presented with stage I disease, 64.4% had locally advanced disease. HIV infection was the major comorbidity (64.4%). The rate of complete remission at the end of treatment was at 49% while the 2-year overall survival (OS) and local recurrence-free survival were 86.4% and 91.3%, respectively. Despite high HIV coinfection in the cohort, AC treatment outcomes were not significantly associated with HIV status. Disease stage (P = .012) and grade (P = .030) were significantly associated with 2-year OS.

CONCLUSION

Patients with anal SCC in Tanzania present mainly with locally advanced disease associated with high HIV prevalence. In this cohort, the SCC grade was independently associated with treatment outcomes unlike other factors such as HIV coinfection.

Prognostic Factors of Long-Term Outcomes after Primary Chemo-Radiotherapy in Non-Metastatic Anal Squamous Cell Carcinoma: An International Bicentric Cohort

Anal squamous cell carcinoma (ASCC) is a rare malignancy with a rising incidence associated with human papillomavirus (HPV) infection. The locally advanced disease is associated with a 30% rate of treatment failure after standard chemoradiotherapy (CRT). We aimed to elucidate the prognostic factors for ASCC after curative CRT. A retrospective multicenter study of 176 consecutive patients with ASCC having completed CRT treated between 2010 and 2017 at two centers was performed. Complete response (CR), disease-free survival (DFS), and overall survival (OS) were analyzed by Kaplan–Meier estimates with log-rank tests. The hierarchical clustering on principal components (HCPC) method was employed in an unsupervised and multivariate approach. The CR rate was 70% and was predictive of DFS (p < 0.0001) and OS (p < 0.0001), where non-CR cases were associated with shorter DFS (HR = 16.5, 95% CI 8.19–33.21) and OS (HR = 8.42, 95% CI 3.77–18.81) in a univariate analysis. The median follow-up was 38 months, with a 3-year DFS of 71%. The prognostic factors for DFS were cT1-T2 (p = 0.0002), N0 (p = 0.035), HIV-positive (p = 0.047), HIV-HPV coinfection (p = 0.018), and well-differentiated tumors (p = 0.037). The three-year OS was 81.6%. Female sex (p = 0.05), cT1-T2 (p = 0.02) and well-differentiated tumors (p = 0.003) were associated with better OS. The unsupervised analysis demonstrated a clear segregation of patients in three clusters, identifying that poor prognosis clusters associated with shorter DFS (HR = 1.74 95% CI = 1.25–2.42, p = 0.0008) were enriched with the locally advanced disease, anal canal location, HIV-HPV coinfection, and non-CR. In conclusion, our results reinforce the prognostic value of T stage, N stage, sex, differentiation status, tumor location, and HIV-HPV coinfection in ASCC after CRT.

Characteristics and oncological results of epidermoid anal carcinoma: Comparison analysis between immunocompetent and immunosuppressed patients

OBJECTIVE

Most evidence, including recent randomized controlled trials, analysing anal squamous cell carcinoma (SCC) do not consider immunocompromise patient population. The aim of this study was to compare clinical and oncological outcomes among immunocompetent and immunocompromised patients with anal squamous cell carcinoma.

METHOD

Multicentric retrospective comparative study including 2 cohorts of consecutive patients, immunocompetent and immunocompromised, diagnosed with anal SCC. This study evaluated clinical characteristics, clinical response to radical chemoradiotherapy (CRT) and long-term oncological results including both local and distant recurrence, overall survival (OS) and disease-free survival (DFS).

RESULTS

A total of 84 patients, 47 (55.6%) female, diagnosed with anal SCC from January 2012 to December 2017 were included, 22 (26%) and 62 (74%) patients in immunocompromised and immunocompetent groups respectively. Patients in immunocompromised group were significantly younger (53 vs. 61 years; P = 0.001), with smaller tumoral size (P = 0.044) and reported higher rates of substance abuse including tobacco use (P = 0.034) and parenteral drug consumption (P = 0.001). No differences were found in administered therapies (P = 301) neither in clinical response to chemoradiotherapy (83 vs. 100%). Moreover, similar 5-year OS (60 vs. 64%; P = 0.756) and DFS (65 vs. 68%; P = 0.338) were observed.

CONCLUSION

The present study shows no significant differences in long-term oncological results among immunocompetent and immunocompromised patients diagnosed with anal SCC, with a similar oncologic treatment. This evidence might be explained due to the close monitoring and adequate therapeutic control of HIV positive patients.

Cure Rates According to Dose-Intensity of Chemoradiation in T2N0 Squamous Cell Carcinoma of the Anal Canal

BACKGROUND

Patients with T2N0 squamous cell carcinoma of the anal canal (SCCA) have comprised less than 30% of patients enrolled in phase III clinical trials of curative-intent definitive chemoradiation. We aimed to evaluate treatment outcomes of these patients according to dose-intensity of chemoradiation.

MATERIALS AND METHODS

Retrospective multicenter study of patients with T2N0 SCCA, with the primary endpoint to compare the progression-free survival (PFS) of patients treated with full definitive chemoradiotherapy (f-CRT, CRT with 2 drugs) versus a nonstandard treatment (NST; radiotherapy only or CRT with 1 drug). Secondary outcomes were rates of complete response (CR), salvage surgery, and colostomy. PFS time was analyzed using the Kaplan-Meier method and differences in survival outcomes were assessed using the log-rank test and adjusted for prognostic covariates using a multivariable Cox regression model RESULTS: From March 2006 to January 2020, 74 patients were included. Most patients (n = 58; 78.4%) received f-CRT. In a median follow up time of 66.1 months, the unadjusted median PFS was 128.3 months (95% confidence interval [CI] 105.5-151.1) for f-CRT versus 74.1 months for NST (95% CI 45.8-102.4; P = .067). CR was achieved by 51 (87.9%) versus 11 (68.9%; P = .065) patients treated with f-CRT or an NST, respectively. Comparing f-CRT versus NST, the colostomy rates were higher for those treated with an NST: 5 (32.8%) versus 5 (9.5%; P = .019) CONCLUSION: For patients with T2N0 SCCA, f-CRT remains the standard treatment, offering higher CR and less likelihood of colostomy.

Characteristics and oncological results of epidermoid anal carcinoma: Comparison analysis between immunocompetent and immunosuppressed patients

OBJECTIVE

Most evidence, including recent randomized controlled trials, analysing anal squamous cell carcinoma (SCC) do not consider immunocompromise patient population. The aim of this study was to compare clinical and oncological outcomes among immunocompetent and immunocompromised patients with anal squamous cell carcinoma.

METHOD

Multicentric retrospective comparative study including 2 cohorts of consecutive patients, immunocompetent and immunocompromised, diagnosed with anal SCC. This study evaluated clinical characteristics, clinical response to radical chemoradiotherapy (CRT) and long-term oncological results including both local and distant recurrence, overall survival (OS) and disease-free survival (DFS).

RESULTS

A total of 84 patients, 47 (55.6%) female, diagnosed with anal SCC from January 2012 to December 2017 were included, 22 (26%) and 62 (74%) patients in immunocompromised and immunocompetent groups respectively. Patients in immunocompromised group were significantly younger (53 vs. 61 years; P=0.001), with smaller tumoral size (P=0.044) and reported higher rates of substance abuse. including tobacco use (P=0.034) and parenteral drug consumption (P=0.001). No differences were found in administered therapies (P=301) neither in clinical response to chemoradiotherapy (83 vs. 100%). Moreover, similar 5-year OS (60 vs. 64%; P=0.756) and DFS (65 vs. 68%; P=0.338) were observed.

CONCLUSION

The present study shows no significant differences in long-term oncological results among immunocompetent and immunocompromised patients diagnosed with anal SCC, with a similar oncologic treatment. This evidence might be explained due to the close monitoring and adequate therapeutic control of HIV positive patients.

Anal squamous cell carcinoma: standards of care, new data and ongoing clinical trials

PURPOSE OF REVIEW

To summarize current standards of care, discuss results of recent studies and present ongoing clinical trials for anal squamous cell carcinoma (ASCC).

RECENT FINDINGS

Over the last year, no practice changing studies have been reported in the setting of localised ASCC. A number of retrospective analyses, however, have provided practice-informing data, such as those confirming the negative impact of low compliance to chemoradiotherapy (CRT) on patient outcomes. In contrast, and for the first time, randomized evidence has become available to inform the management of advanced tumours. The InterAACT trial represents a key milestone in the evidence-building process for this disease, establishing carboplatin plus paclitaxel as a new standard of care for treatment-naïve advanced ASCC patients. Furthermore, more data have accumulated about the value of triplet chemotherapy in the first-line setting and of immune checkpoint inhibitors (either as single agents or in combination with other agents) in the refractory setting.

SUMMARY

Recent findings have the potential to improve the treatment quality standards and overall outcome of patients with either localised or advanced ASCC. Results from ongoing clinical trials will hopefully provide useful insights into the management of this disease and further shape current treatment paradigms.

Evidence-based recommendations for gastrointestinal cancers during the COVID-19 pandemic by the Brazilian Gastrointestinal Tumours Group

PURPOSE

As of 2020, the world is facing the great challenge of the COVID-19 (Coronavirus disease 2019) pandemic, caused by the SARS-CoV-2 virus. While the overall mortality is low, the virus is highly virulent and may infect millions of people worldwide. This will consequently burden health systems, particularly by those individuals considered to be at high risk of severe complications from COVID-19. Such risk factors include advanced age, cardiovascular and pulmonary diseases, diabetes and cancer. However, few data on the outcomes of cancer patients infected by SARS CoV-2 exist. Therefore, there is a lack of guidance on how to manage cancer patients during the pandemic. We sought to propose specific recommendations about the management of patients with gastrointestinal malignancies.

METHODS

The Brazilian Gastrointestinal Tumours Group board of directors and members sought up-to-date scientific literature on each tumour type and discussed all recommendations by virtual meetings to provide evidence-based-and sometimes, expert opinion-recommendation statements. Our objectives were to recommend evidence-based approaches to both treat and minimise the risk of COVID-19 for cancer patients, and simultaneously propose how to decrease the use of hospital resources at a time these resources need to be available to treat COVID-19 patients.

RESULTS

Overall and tumour-specific recommendations were made by stage (including surgical, locoregional, radiotherapy, systemic treatments and follow-up strategies) for the most common gastrointestinal malignancies: esophagus, gastric, pancreas, bile duct, hepatocellular, colorectal, anal cancer and neuroendocrine tumours.

CONCLUSIONS

Our recommendations emphasise the importance of treating cancer patients, using the best evidence available, while simultaneously taking into consideration the world-wide health resource hyperutilisation to treat non-cancer COVID-19 patients.