Anal cancer: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up☆

Anal carcinoma - exploring the epidemiology, risk factors, pathophysiology, diagnosis, and treatment

Anal carcinoma is a relatively rare tumor that accounts for approximately 2% of gastrointestinal malignancies and less than 7% of anorectal cancers. Most anal tumors originate between the anorectal junction and the anal verge. Risk factors for the disease include human papillomavirus infection, human immunodeficiency virus, tobacco use, immunosuppression, female sex, and older age. The pathogenesis of anal carcinoma is believed to be linked to human papillomavirus-related inflammation, leading to dysplasia and progression to cancer. Squamous cell carcinoma is the most common type of anal tumor, with an annual incidence of approximately 1 to 2 per 100000 persons. Treatment regarding anal cancer has emerged over time. However, chemoradiation therapy remains the mainstay approach for early localized disease. Patients with metastatic disease are treated with systemic therapy, and salvage surgery is reserved for disease recurrence following chemoradiation. This article aims to provide background information on the epidemiology, risk factors, pathology, diagnosis, and current trends in the management of anal cancer. Future directions are briefly discussed.

Gastroenterology healthcare in LGBTQ+ individuals

Lesbian, gay, bisexual, transgender, queer, or questioning individuals, as well as those with another diverse identity (LGBTQ+), present specific nuances in healthcare that physicians must consider in clinical practice. Particularly, gastroenterologists are nowadays facing different issues in several fields regarding LGBTQ+ healthcare, such as endoscopy, inflammatory bowel disease, hepatology, and proctology. In this study, the authors provide a practice-oriented and up-to-date review reinforcing the importance of some of the most prevalent pathologies associated with sexuality that gastroenterologists may encounter in their clinical practice. In terms of endoscopy, authors describe the endoscopic findings related to human papillomavirus (HPV) infection: the esophageal squamous papilloma and cell carcinoma; also highlight the importance of retroflexion maneuver during a routine colonoscopy that allows detection of anal intraepithelial neoplasia lesions that can be anal cancer precursors. Regarding inflammatory bowel disease, some considerations are made about the differential diagnosis with infectious proctitis, and the topic of the risk of anal cancer due to HPV infection, in this specific population, is also addressed. Considering hepatology, the authors review the most important issues related to hepatotropic sexually transmitted infections. The authors also make some comments regarding the possibility of drug-induced liver injury in gender-affirming hormone therapy and pre-exposure prophylaxis for HIV prevention. Finally, considering the proctology field, an up-to-date review is performed regarding anal cancer screening, HPV infection and related diseases, and infectious proctitis management.

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.

Electron beam radiotherapy for the management of squamous cell carcinoma of the anal margin

PURPOSE AND OBJECTIVE

Squamous cell carcinoma of the anal margin (SCCAM) is an uncommon lesion that comprises one-third to a quarter of all anal squamous cell carcinoma. Treatment involves surgery or exclusive radiotherapy for small tumours, whereas the preferred treatment for larger tumours is chemoradiotherapy. In our department, selected patients with SCCAM are treated with electron beam radiotherapy using one perineal field. The present study evaluates this strategy.

MATERIAL AND METHODS

All consecutive patients with SCCAM and treated with electron beam radiotherapy from 2012 to 2022 were included. Data were retrospectively extracted from the medical records and analysed descriptively. Local control (LC) and overall survival (OS) were analysed using Kaplan-Meier statistics.

RESULTS

Forty patients were evaluated. Primary radiotherapy was delivered in 35 (87.5%) patients. Five (12.5%) patients had postoperative radiotherapy. Median prescription dose was 60.0 (range 45.0-60.2) Gy in 28 (range 10-30) fractions delivered with 8 (range 4-18) MeV using a standard circular aperture and bolus. At a median follow-up of 73 (range 9-135) months, 7 (17.5%) patients were diagnosed with local recurrences. The 5-year LC rate was 84.3% (95% CI: 71.4%-97.2%). Analysis of LC according to T-stage revealed a 5-year LC of 100% (95% CI: 100%-100%) in T1 tumours compared to 57.0% (95% CI: 27.4%-86.6%) in T2 tumours (p < 0.001). 5-year OS was 91.6% (95% CI: 83.0%-100%). Late grade 3 toxicity included ulceration in the skin and subcutis in 2 (5.0%) patients.

INTEPRETATION

Electron beam radiotherapy enables the delivery of 'eye-guided' radiotherapy directly to the tumour. LC is good in patients with T1 tumours. Patients with T2 tumours have less satisfactory LC and should be treated with chemoradiotherapy. Electron beam radiotherapy enables the delivery of "eye-guided" RT directly to the tumour. LC is excellent in patients with T1 tumours. Patients with T2 tumours have less satisfactory LC and should be treated with chemoradiotherapy.

Prognostic Value of 18F-FDG PET/CT Assessment After Radiotherapy of Squamous Cell Carcinoma of the Anus in Patients from the National Multicentric Cohort FFCD-ANABASE

This study aimed to evaluate the prognostic value of 18F-FDG PET/CT qualitative assessment in terms of recurrence-free survival (RFS), colostomy-free survival (CFS), and overall survival (OS) after radiation therapy (RT) of squamous cell carcinoma of the anus (SCCA). Secondary objectives were to evaluate the prognostic value of baseline and posttherapeutic quantitative 18F-FDG PET/CT parameters in terms of RFS, CFS, and OS. Methods: We included all consecutive patients from the French multicentric cohort FFCD-ANABASE who had undergone 18F-FDG PET/CT at baseline and 4-6 mo after RT or chemoradiotherapy for a localized SCCA. Qualitative assessments separated patients with complete metabolic response (CMR) and non-CMR. Quantitative parameters were measured on baseline and posttreatment 18F-FDG PET/CT. RFS, CFS, and OS were analyzed using the Kaplan-Meier method. Associations among qualitative assessments, quantitative parameters, and RFS, CFS, and OS were analyzed using univariate and multivariate Cox regression. Results: Among 1,015 patients treated between January 2015 and April 2020, 388 patients (300 women and 88 men) from 36 centers had undergone 18F-FDG PET/CT at diagnosis and after treatment. The median age was 65 y (range, 32-90 y); 147 patients (37.9%) had an early-stage tumor and 241 patients (62.1%) had a locally advanced-stage tumor; 59 patients (15.2%) received RT, and 329 (84.8%) received chemoradiotherapy. The median follow-up was 35.5 mo (95% CI, 32.8-36.6 mo). Patients with CMR had better 3-y RFS, CFS, and OS, at 84.2% (95% CI, 77.8%-88.9%), 84.7% (95% CI, 77.2%-89.3%), and 88.6% (95% CI, 82.5%-92.7%), respectively, than did non-CMR patients, at 42.1% (95% CI, 33.4%-50.6%), 47.9% (95% CI, 38.1%-56.8%), and 63.5 (95% CI, 53.2%-72.1%), respectively (P < 0.0001). Quantitative parameters were available for 154 patients from 3 centers. The following parameters were statistically significantly associated with 3-y RFS: baseline SUVmax (primitive tumor [T]) (hazard ratio [HR], 1.05 [95% CI, 1.01-1.1; P = 0.018]), SUVpeak (T) (HR, 1.09 [95% CI, 1.02-1.15; P = 0.007]), MTV 41% (T) (HR, 1.02 [95% CI, 1-1.03; P = 0.023]), MTV 41% (lymph node [N]) (HR, 1.06 [95% CI, 1.03-1.1; P < 0.001]), MTV 41% (T + N) (HR, 1.02 [95% CI, 1-1.03; P = 0.005]), and posttreatment SUVmax (HR, 1.21 [95% CI, 1.09-1.34; P < 0.001]). Conclusion: Treatment response assessed by 18F-FDG PET/CT after RT for SCCA has a significant prognostic value.18F-FDG PET/CT could be useful for adapting follow-up, especially for patients with locally advanced-stage tumors. Quantitative parameters could permit identification of patients with a worse prognosis but should be evaluated in further trials.

HPV status and immunohistochemical analysis of p16, p53 and PD‑L1 expression as prognostic biomarkers in patients with squamous cell anal cancer receiving definitive radiotherapy/chemoradiotherapy

Anal squamous cell carcinoma (SCC) treated with definitive radiotherapy (RT)/chemoradiotherapy (CRT) has shown high success rates, yet challenges such as treatment resistance and recurrence persist. The present study aimed to investigate the associations between immunohistochemical (IHC) evaluation, treatment response and prognosis in anal SCC. A retrospective cohort analysis included 42 patients with anal SCC treated at a single institution between 2006 and 2022. Human papillomavirus (HPV) status was determined, and the IHC analysis of p16, p53 and PD-L1 expression was conducted using formalin-fixed, paraffin-embedded biopsies. A complete response to RT/CRT was observed in 71.4% of patients. Recurrence occurred in 38.1% of cases, of which 7.1% had local-regional recurrence (LRR), 14.3% had distant recurrence (DR), and 16.7% had both LRR and DR. HPV positivity (71.4%) was significantly associated with p16 positivity. Lack of complete response was associated with HPV-negative status, p16-negative status, increased recurrence and DR. In addition, recurrence was significantly associated with p53-positive status, and p53 positivity was significantly associated with increased LRR. PD-L1 positivity, defined as a combined positive score (CPS) ≥1% was found in 73.8% of the patients, and exhibited significant associations with HPV positivity and p16 positivity. PD-L1 CPS ≥ 1% was also associated with an increased LRR. Univariate analysis revealed that age <65 years, a complete response and HPV positivity were associated with increased 5-year overall survival (OS), while a complete response, HPV positivity and p53-negative status were associated with increased 5-year disease-free survival (DFS). Multivariate analysis identified that age <65 years and HPV positivity are independent prognostic factors for 5-year OS, and a complete response and p53-negative status are independent prognostic factors for 5-year DFS. In conclusion, these findings suggust that the identification of HPV status and poor prognostic biomarkers at diagnosis may be used to guide personalized treatment strategies, with the combination of immunotherapy with standard CRT potentially providing improved outcomes.

Perianal disease in inflammatory bowel disease: Broadening treatment and surveillance strategies for anal cancer

The perianal disease affects up to one-third of individuals with Crohn's disease (CD), causing disabling symptoms and significant impairment in quality of life, particularly for those with perianal fistulising CD (PFCD). The collaborative effort between gastroenterologists and surgeons is essential for addressing PFCD to achieve fistula closure and promote luminal healing. Limited fistula healing rates with conventional therapies have prompted the emergence of new biological agents, endoscopic procedures and surgical techniques that show promising results. Among these, mesenchymal stem cells injection is a particularly hopeful therapy. In addition to the burden of fistulas, individuals with perianal CD may face an increased risk of developing anal cancer. This underscores the importance of surveillance programmes and timely interventions to prevent late diagnoses and poor outcomes. Currently, there is no established formal anal screening programme. In this review, we provide an overview of the current state of the art in managing PFCD, including novel medical, endoscopic and surgical approaches. The discussion also focuses on the relevance of establishing an anal cancer screening programme in CD, intending to propose a risk-based surveillance algorithm. The validation of this surveillance programme would be a significant step forward in improving patient care and outcomes.

Total pelvic exenteration extended to pelvic bones with subsequent VRAM flap reconstruction in patient with recurrent anal squamous cell carcinoma following chemoradiotherapy

Anal squamous cell carcinoma, typically associated with human papillomavirus infection, remains a rare malignancy. This article outlines a case of local recurrence in a male patient with a history of HIV and hepatitis C virus infection, previously treated with chemoradiotherapy. Extensive tumour involvement called for total pelvic exenteration extended to anterior osteomuscular compartment and genitalia. The surgical approach involved multidisciplinary collaboration and detailed preoperative planning using three-dimensional reconstruction. Key surgical considerations comprised the following: achieving tumour-free margins (R0 resection), extensive osteotomies and intricate pelvic floor reconstruction with prosthetic mesh and flap reconstruction. The procedure successfully yielded an R0 resection, maintaining adequate lower limb functionality. Our case report underscores the benefits of pelvic exenteration in locally advanced or recurrent pelvic tumours, invariably following careful patient selection and exhaustive preoperative studies.

Chemoradiotherapy versus radiotherapy alone in the management of early-stage anal squamous cell carcinoma: A comparative analysis of the French cohort FFCD-ANABASE

INTRODUCTION

Early-stage anal squamous cell carcinomas (ASCC) are usually treated with chemoradiotherapy (CRT), with good outcomes. Radiotherapy (RT) alone might be sufficient while reducing toxicity.

METHODS

Patients included in the French prospective FFCD-ANABASE and treated for T1-2N0 ASCC between 2015/01 and 2020/04 were divided into CRT and RT groups. Clinical outcomes and toxicity were reported. Propensity score matching was conducted for 105 pairs of patients.

RESULTS

440 patients were analyzed: 261 (59.3 %) in the CRT group and 179 (40.7 %) in the RT group. The median follow-up was 35.7 months. Patients receiving CRT were younger, had better Performance Status (PS) and larger tumors. No statistical difference was observed for 3-year Disease-free survival (85.3 % vs 83 %, p = 0.28), Overall survival (89.6 % vs 94.8 %, p = 0.69) and Colostomy-free survival (84.5 % vs 87.2 %, p = 0.84) between CRT and RT groups, respectively. Propensity score-matched analysis confirmed these findings. Treatment interruptions were significantly more frequent in the CRT group (36.3 % vs 21.9 %, p = 0.0013), resulting in an Overall Treatment Time (OTT) extended by 7 days. Grade 3 CTCAE v4.0 toxicities were more prevalent in the CRT group (46 % vs 19 %, p < 0.001).

CONCLUSION

Adding chemotherapy to radiotherapy did not significantly improve outcomes for T1-2N0 ASCC in our study, but increased toxicity and OTT.

Feasibility of weekly cisplatin and radiotherapy for localized anal cancer - A Danish anal cancer group report

BACKGROUND

Chemoradiotherapy (CRT) with flourouracil and mitomycin is the standard treatment for squamous cell carcinomas of the anus (SCCA), however the associated acute toxicity often hinders compliance. Although weekly cisplatin is a well-established treatment for other squamous cell carcinomas, it has not been explored in SCCA.

PURPOSE

To investigate if radiotherapy (RT) with weekly cisplatin is a feasible option for SCCA and to report the acute toxicity.

MATERIAL/METHODS

Patients were treated with RT and weekly cisplatin 40 mg/m2 between 1998-2020. Retrospective data from medical records (n=65) and prospectively collected data from an observational study (n=51) comprising physician assessed toxicity (NCI-CTCAE 4.0), patient-reported outcomes (EORTC-QlQC30 + CR29) baseline, mid-therapy, end of treatment and 2-4 weeks post-treatment were included. Disease-free survival (DFS) and overall survival (OS) were estimated using the Kaplan-Meier method.

RESULTS

We included 116 patients. T-stages were T1:4%, T2: 71%, T3: 17%, T4: 8% and 47% has N+ disease. RT doses were 53.75-64 Gy/45-51.2 Gy and the mean cumulative dose of cisplatin was 307.5 mg. The median overall treatment time was 43 days. Within 6 months after CRT 88.9 % had complete response. The median follow-up time was 4.5 years and 5-year DFS and OS were 77% (95%CI 68.7;84.5%) and 86.4% (95%CI 78.3;91.7%), respectively. Hospitalization occured in 20% with 2.6% being admitted due to febrile neutropenia. Hematological toxicity was low with 13.7% grade 3 and 3.9% grade 4. Anal pain, skin, gastrointestinal and urogenital toxicity were mild.

CONCLUSION

RT and weekly cisplatin for SCCA showed good outcome results and an acceptable acute toxicity profile.

Diffusion-weighted magnetic resonance imaging as an early prognostic marker of chemoradiotherapy response in squamous cell carcinoma of the anus: An individual patient data meta-analysis

Background and purpose

Squamous cell carcinoma of the anus (SCCA) can recur after chemoradiotherapy (CRT). Early prediction of treatment response is crucial for individualising treatment. Existing data on radiological biomarkers is limited and contradictory. We performed an individual patient data meta-analysis (IPM) of four prospective trials investigating whether diffusion-weighted (DW) magnetic resonance imaging (MRI) in weeks two to three of CRT predicts treatment failure in SCCA.

Material and methods

Individual patient data from four trials, including paired DW-MRI at baseline and during CRT, were combined into one dataset. The association between ADC volume histogram parameters and treatment failure (locoregional and any failure) was assessed using logistic regression. Pre-defined analysis included categorising patients into a change in the mean ADC of the delineated tumour volume above and below 20%.

Results

The study found that among all included 142 patients, 11.3 % (n = 16) had a locoregional treatment failure. An ADC mean change of <20 % and >20 % resulted in a locoregional failure rate of 16.7 % and 8.0 %, respectively. However, no other ADC-based histogram parameter was associated with locoregional or any treatment failure.

Conclusions

DW-MRI standard parameters, as an isolated biomarker, were not found to be associated with increased odds of treatment failure in SCCA in this IPM. Radiological biomarker investigations involve multiple steps and can result in heterogeneous data. In future, it is crucial to include radiological biomarkers in large prospective trials to minimize heterogeneity and maximize learning.

Clinical outcomes of pelvic bone marrow sparing radiotherapy for cervical cancer: A systematic review and meta-analysis of randomised controlled trials

Background

Concurrent chemoradiotherapy (CRT) is the standard treatment for locally advanced cervical cancer. We investigated how additional bone marrow sparing (BMS) affects the clinical outcomes.

Methods

We queried MEDLINE, Embase, Web of Science Core Collection, Google Scholar, Sinomed, CNKI, and Wanfang databases for articles published in English or Chinese between 2010/01/01 and 2023/10/31. Full-text manuscripts of prospective, randomised trials on BMS in cervical cancer patients treated with definitive or postoperative CRT were included. Risk of bias (RoB) was assessed using Cochrane Collaboration's RoB tool. Random-effects models were used for the meta-analysis.

Results

A total of 17 trials encompassing 1297 patients were included. The majority were single-centre trials (n = 1268) performed in China (n = 1128). Most trials used CT-based anatomical BMS (n = 1076). There was a comparable representation of trials in the definitive (n = 655) and postoperative (n = 582) settings, and the remaining trials included both.Twelve studies reported data on G ≥ 3 (n = 782) and G ≥ 2 (n = 754) haematologic adverse events. Both G ≥ 3 (OR 0.39; 95 % CI 0.28-0.55; p < 0.001) and G ≥ 2 (OR 0.29; 95 % CI 0.18-0.46; p < 0.001) toxicity were significantly lowered, favouring BMS. Seven studies (n = 635) reported data on chemotherapy interruptions, defined as receiving less than five cycles of cisplatin, which were significantly less frequent in patients treated with BMS (OR 0.44; 95 % CI 0.24-0.81; p = 0.016). There was no evidence of increased gastrointestinal or genitourinary toxicity.There were no signs of significant heterogeneity. Four studies were assessed as high RoB; sensitivity analyses excluding these provided comparable results for main outcomes. The main limitations include heterogeneity in BMS methodology between studies, low representation of populations most affected by cervical cancer, and insufficient data to assess survival outcomes.

Conclusions

The addition of BMS to definitive CRT in cervical cancer patients decreases hematologic toxicity and the frequency of interruptions in concurrent chemotherapy. However, data are insufficient to verify the impact on survival and disease control.

Screening and prevention of HPV-related anogenital cancers in women living with HIV in Europe: Results from a systematic review

BACKGROUND

Women living with HIV (WLWH) are at increased risk of human papillomavirus (HPV)-related cancers. Throughout Europe, there is great heterogeneity among guidelines for screening programmes, access to HPV testing and HPV vaccination. The aim of this systematic review is to summarize available data on screening and prevention measures for HPV-related anogenital cancers in WLWH across the WHO European Region (WER).

METHODS

The systematic review followed the PRISMA guidelines and was registered on Prospero. PubMed, Embase and Web of Science databases were searched to identify available studies, written in English and published between 2011 and 2022. A metanalysis was conducted using random-effects models to calculate pooled prevalence of HPV. Subgroup analyses were conducted according to country and HPV testing.

RESULTS

Thirty-four articles involving 10 336 WLWH met the inclusion criteria. Studies were heterogenous in their methodology and presentation of results: 73.5% of studies focused on cervical cancer prevention, and only 4.4% on anal cancer; 76.5% of studies conducted HPV testing as a routine part of screening. The prevalence of high-risk HPV was 30.5-33.9% depending on the detection method used. A total of 77% of WLWH had cervical cytology results reported. Six studies reported the positive association of CD4 cell count <200 cells/μL with HPV prevalence and cervical abnormalities. Anal HPV testing was conducted in <8% of participants. HPV vaccination was completed in 5.6% of women (106/1902) with known vaccination status. There was no information about the vaccination status of the majority of women in the analysed studies (8434/10336).

CONCLUSION

Data about screening of HPV-related anogenital cancer in WLWH in Europe are heterogenous and lacking, especially in relation to anal cancer. HPV DNA testing is not routinely done as part of screening for HPV-related cancer; guidelines should include indications for when to use this test. Low CD4 count is a risk factor for HPV infection and cytological abnormalities. HPV vaccination data are poor and, when available, vaccination rates are very low among WLWH in Europe. This review concludes that significant improvements are required for data and also consistency on guidelines for HPV screening, prevention and vaccination in WLWH.

Patient reported long-term side effects from treatment on urinary and sexual function in anal cancer survivors - 3- and 6-year results from the Swedish national ANCA study

AIM

The standard treatment for anal cancer is chemoradiotherapy. Most patients survive anal cancer but remain living with long-term side effects related to the treatment received. The aim of this study was to assess the occurrence of long-term impairment of urinary and sexual function at 3 and 6 years after diagnosis and to investigate the additive effect from chemotherapy in combined chemoradiotherapy on urinary incontinence, compared to radiotherapy alone.

METHOD

The ANal CAncer study (ANCA) is based on a national Swedish cohort of patients diagnosed with anal cancer between 2011 and 2013. All identified patients within the study were invited to respond to a study-specific questionnaire at 3 and 6 years. Descriptive analyses for the primary endpoint were performed. To investigate a possible additional effect from chemotherapy logistic regression was used.

RESULTS

A total of 388 patients were included in the study. At 3 years 264 patients were alive and invited to respond to an anal cancer specific questionnaire. The 3- and 6 year response rates were 195 (74%) and 155 patients (67%), respectively. The patient reported urinary function impairment at 3 years were urgency (63%), incomplete bladder emptying (47%), and incontinence (46%) and there was an absolute increase of the prevalence of urinary dysfunction in about 10% at 6 years. Three years after diagnosis, 77% reported that intercourse was not part of their sex life; this percentage increased at 6 years to 83%. We found no negative effect of chemotherapy in combined chemoradiotherapy versus radiotherapy alone on patient reported urinary incontinence.

CONCLUSION

For anal cancer survivors, urinary function was impaired after 3 years and continued to deteriorate as measured at 6 years after diagnosis. Anal cancer and its treatment negatively affected sexual function for both men and women. This may explain why patients reported that sexual activity and frequency of intercourse was not of importance in their life.

Perianal Fistulizing Crohn's Disease-Associated Anorectal and Fistula Cancers: Systematic Review and Expert Consensus

BACKGROUND & AIMS

Perianal fistulizing Crohn's disease (PFCD)-associated anorectal and fistula cancers are rare but often devastating diagnoses. However, given the low incidence and consequent lack of data and clinical trials in the field, there is little to no guidance on screening and management of these cancers. To inform clinical practice, we developed consensus guidelines on PFCD-associated anorectal and fistula cancers by multidisciplinary experts from the international TOpClass consortium.

METHODS

We conducted a systematic review by standard methodology, using the Newcastle-Ottawa Scale quality assessment tool. We subsequently developed consensus statements using a Delphi consensus approach.

RESULTS

Of 561 articles identified, 110 were eligible, and 76 articles were included. The overall quality of evidence was low. The TOpClass consortium reached consensus on 6 structured statements addressing screening, risk assessment, and management of PFCD-associated anorectal and fistula cancers. Patients with long-standing (>10 years) PFCD should be considered at small but increased risk of developing perianal cancer, including squamous cell carcinoma of the anus and anorectal carcinoma. Risk factors for squamous cell carcinoma of the anus, notably human papilloma virus, should be considered. New, refractory, or progressive perianal symptoms should prompt evaluation for fistula cancer. There was no consensus on timing or frequency of screening in patients with asymptomatic perianal fistula. Multiple modalities may be required for diagnosis, including an examination under anesthesia with biopsy. Multidisciplinary team efforts were deemed central to the management of fistula cancers.

CONCLUSIONS

Inflammatory bowel disease clinicians should be aware of the risk of PFCD-associated anorectal and fistula cancers in all patients with PFCD. The TOpClass consortium consensus statements outlined herein offer guidance in managing this challenging scenario.

Local excision versus radical surgery for anal squamous cell carcinoma: a multicenter study in Japan

BACKGROUND

The standard treatment for anal squamous cell carcinoma is chemoradiation therapy (CRT), but there is a possibility of over-treatment for early-stage disease. cTisN0 and cT1N0 disease is currently indicated for local excision, but it is unclear whether the indication of local excision can be expanded to cT2N0 disease.

METHODS

126 patients with cTis-T2N0 anal cancer treated at 47 centers in Japan between 1991 and 2015 were included. Patients were first classified into the CRT group and surgical therapy group according to the initial therapy, and the latter was further divided into local excision (LE) and radical surgery (RS) groups. We compared prognoses among the groups, and analyzed risk factors for recurrence after local excision.

RESULTS

The CRT group (n = 87) and surgical therapy group (n = 39) showed no difference in relapse-free survival (p = 0.29) and overall survival (p = 0.94). Relapse-free survival curves in the LE (n = 23) and RS groups (n = 16) overlapped for the initial 3 years, but the curve for the LE group went lower beyond (p = 0.33). By contrast, there was no difference in overall survival between the two groups (p = 0.98). In the LE group, the majority of recurrences distributed in locoregional areas, which could be managed by salvage treatments. Muscular invasion was associated with recurrence after local excision (hazard ratio: 22.91, p = 0.011).

CONCLUSION

LE may be applied to selected patients with anal cancer of cTis-T2N0 stage. Given the high risk of recurrence in cases with muscular invasion, it may be important to consider close surveillance and additional treatment in such patients.

Human papillomavirus infection and the risk of cancer at specific sites other than anogenital tract and oropharyngeal region: an umbrella review

BACKGROUND

Despite numerous studies having evaluated the associations between human papillomavirus (HPV) infection and risk of specific cancers other than anogenital tract and oropharyngeal, the findings are inconsistent and the quality of evidence has not been systematically quantified. We aimed to summarise the existing evidence as well as to evaluate the strength and credibility of these associations.

METHODS

We conducted an umbrella review of systematic reviews and meta-analyses of observational studies. PubMed, EMBASE, and Web of Science were searched from inception to March 2024. Studies with systematic reviews and meta-analyses that examined associations between HPV or HPV-associated genotypes infection and specific cancers were eligible for this review. The quality of the methodology was evaluated using A Measurement Tool to Assess systematic Reviews (AMSTAR). The credibility of the evidence was assessed using GRADE. The protocol was preregistered with PROSPERO (CRD42023439070).

FINDINGS

The umbrella review identified 31 eligible studies reporting 87 associations with meta-analytic estimates, including 1191 individual studies with 336,195 participants. Of those, 29 (93.5%) studies were rated as over moderate quality by AMSTAR. Only one association indicating HPV-18 infection associated with an increased risk of breast cancer (odds ratio [OR] = 3.48, 95% confidence interval [CI] = 2.24-5.41) was graded as convincing evidence. There were five unique outcomes identified as highly suggestive evidence, including HPV infection increased the risk of oral squamous cell carcinoma (OR = 7.03, 95% CI = 3.87-12.76), oesophageal cancer (OR = 3.32, 95% CI = 2.54-4.34), oesophageal squamous cell carcinoma (OR = 2.69, 95% CI = 2.05-3.54), lung cancer (OR = 3.60, 95% CI = 2.59-5.01), and breast cancer (OR = 6.26, 95% CI = 4.35-9.00). According to GRADE, one association was classified as high, indicating that compared with the controls in normal tissues, HPV infection was associated with an increased risk of breast cancer.

INTERPRETATION

The umbrella review synthesised up-to-date observational evidence on HPV infection with the risk of breast cancer, oral squamous cell carcinoma, oesophageal cancer, oesophageal squamous cell carcinoma, and lung cancer. Further larger prospective cohort studies are needed to verify the associations, providing public health recommendations for prevention of disease.

FUNDING

National Key Research and Development Program of China, Natural Science Foundation of China, Outstanding Scientific Fund of Shengjing Hospital of China Medical University, and 345 Talent Project of Shengjing Hospital of China Medical University.

Comparison between pelvic MRI, CT, and PET/CT in baseline staging and radiation planning of anal squamous cell carcinoma

PURPOSE

To investigate the differences in baseline staging of anal squamous cell carcinoma based on CT, MRI, and PET/CT, and the resultant impact on the radiation plan.

METHODS

This retrospective study included consecutive patients with anal squamous cell carcinoma who underwent baseline pelvic MRI, CT, and PET/CT (all examinations within 3 weeks of each other) from January 2010 to April 2020. CTs, MRIs, and PET/CTs were re-interpreted by three separate radiologists. Several imaging features were assessed; tumor stage was determined based on the eight edition of the American Joint Committee on Cancer (AJCC) staging manual; and T (tumor), N (node), and M (metastasis) categories were determined based on National Comprehensive Cancer Network (NCCN) guidelines. Radiologist assessments were then randomly presented to a radiation oncologist who formulated the radiation plan in a blinded fashion.

RESULTS

Across 28 patients (median age, 62 years [range, 31-78], T-category classification was significantly different on PET/CT compared to MRI and CT (p = 0.037 and 0.031, respectively). PET/CT staged a higher proportion of patients with T1/T2 disease (16/28, 57%) compared to MRI (11/28, 39%) and CT (10/28, 36%). MRI staged a higher proportion of patients with T3/T4 disease (14/28, 50%) compared to CT (12/28, 43%) and PET/CT (11/28, 39%). However, there was no significant difference between the three imaging modalities in terms of either N-category, AJCC staging, or NCCN TNM group classification, or in treatment planning.

CONCLUSION

Our exploratory study showed that MRI demonstrated a higher proportion of T3/T4 tumors, while PET/CT demonstrated more T1/T2 tumors; however, MRI, CT, and PET/CT did not show any significant differences in AJCC and TNM group categories, nor was there any significant difference in treatment doses between them when assessed independently by an experienced radiation oncologist.

Trends in epidemiology and primary treatment of anal squamous cell carcinoma in the Netherlands (1990-2021)

A rapid increase in the incidence of anal squamous cell carcinoma (SCC) was reported in several countries over the past decades. This study assessed trends in epidemiology and primary treatment over a 32-year period (1990-2021) using the Netherlands Cancer Registry. The study population included 4273 patients, 44.2% male and 55.8% female (median age 63 years). The age-standardised incidence rate (European Standardised Rate, ESR) increased from 0.5 to 1.6 per 100,000, which entailed an average annual percentage change (AAPC) of 5.0% (95% confidence interval [CI]: 4.5%-5.8%). While incidence among females increased continuously over the total period (AAPC 4.9%; 95%CI: 4.4%-5.6%), to 1.8 per 100,000 ESR in 2021, incidence among males increased until 2016 (annual percentage change [APC] of 6.3%; 95%CI: 5.6%-10.7%), after which it seemed to stabilise (APC -2.1%; 95%CI: -16.8%-4.5%). Significant trends were also observed in distribution of age, tumour stage and primary treatment modalities. Five-year relative survival (RS) was estimated using the Pohar-Perme estimator, and this improved from 56.1% in 1990-1997 (95%CI: 49.3%-62.4%) to 67.9% in 2014-2021 (95%CI: 64.7%-70.9%), but remained poor for stage IV disease. Evaluation through a multivariable Poisson regression model demonstrated diagnosis in the most recent period to be independently associated with better RS, in addition to female sex, younger age, early disease stage and any treatment. In conclusion, the rising incidence of anal SCC seems to decline in males, but not in females, and advances in diagnostics and therapeutic management have likely contributed to improved prognosis.

Unveiling the Role of Human Papillomavirus in Urogenital Carcinogenesis a Comprehensive Review

Human papillomavirus (HPV), an oncogenic DNA virus, is the most common sexually transmitted virus and significant public health concern globally. Despite the substantial prevalence of HPV infection among men, routine testing remains elusive due to the lack of approved HPV tests and the complexity of detection methods. Various studies have explored the link between HPV and genitourinary cancers, revealing different associations influenced by geographic variation, histological subtype and methodological differences. These findings underscore the importance of further research to elucidate the role of HPV in male urogenital cancers. This comprehensive review delves into the intricate relationship between HPV and male genitourinary cancers, shedding light on the virus's oncogenic mechanisms and its reported prevalence. A deeper understanding of HPV's implications for male health is essential for advancing public health initiatives and reducing the burden of urogenital cancers worldwide.

Characteristics, Clinical Outcomes, and Prognosis of Anal and Pouch-related Carcinoma in Patients With Crohn's Disease

BACKGROUND

This study described the clinical characteristics, outcomes, and prognosis of Crohn's disease (CD) patients with anal cancer in a tertiary referral center.

METHODS

The electronic medical records of 35 adult CD patients, including CD of the pouch, with anal carcinoma evaluated at Mayo Clinic Rochester, Florida, or Arizona between January 1989 and August 2022 were retrospectively reviewed.

RESULTS

Before cancer diagnosis, patients with pouch-related carcinoma had a shorter median duration of inflammatory bowel disease than those with anal carcinoma (10 vs 26 years). Twenty-six patients (74%) had perianal diseases or rectovaginal fistula, and 35% had a history of human papillomavirus infection. Twenty-one patients (60%) were diagnosed with cancer by anal examination under anesthesia (EUA). More than half of adenocarcinomas were mucinous. Sixteen patients (47%) were American Joint Committee on Cancer (AJCC) Tumor Nodes Metastasis (TNM) stage 3, and 83% were treated by surgery. At last follow-up, 57% of patients were alive without cancer. The 1-, 3- and 5-year overall survival rates were 93.8% (95% confidence interval [CI], 85.7%-100%), 71.5% (95% CI, 56.4%-90.7%), and 67.7% (95% CI, 51.2%-87.7%), respectively. Advanced AJCC TNM stage (hazard ratio, 3.20 per stage; 95% CI, 1.05-9.72; P = .040) was significantly associated with increased risk of death, whereas the period of cancer diagnosis in 2011-2022 (HR, relative to 1989-2000, 0.16; 95% CI, 0.04-0.72; P = .017) was significantly related to decreased risk of death.

CONCLUSIONS

Anal and pouch-related carcinomas were rare complications of CD, and long-standing perianal diseases were an important risk factor. Anal EUA improved the diagnostic yield. Newer cancer treatment strategies and surgery were associated with excellent survival outcome.

Atezolizumab plus modified docetaxel, cisplatin, and fluorouracil as first-line treatment for advanced anal cancer (SCARCE C17-02 PRODIGE 60): a randomised, non-comparative, phase 2 study

BACKGROUND

The modified docetaxel, cisplatin, and fluorouracil (mDCF) regimen has shown efficacy and safety as first-line treatment for advanced squamous cell carcinoma of the anus, making it a standard regimen. Inhibitors of programmed cell death protein 1 and its ligand, such as pembrolizumab, nivolumab, retifanlimab, avelumab, and atezolizumab, have shown some antitumour activity as monotherapy in advanced squamous cell carcinoma of the anus that is refractory to chemotherapy. This phase 2 study evaluated the combination of mDCF and atezolizumab as first-line treatment in advanced squamous cell carcinoma of the anus.

METHODS

In this randomised, open-label, non-comparative, phase 2 study, participants from 21 centres (academic, private, and community hospitals and cancer research centres) across France with chemo-naive, metastatic, or unresectable locally advanced recurrent squamous cell carcinoma of the anus, aged 18 years or older, and with an Eastern Cooperative Oncology Group performance status of 0 or 1, were randomly allocated (2:1) to receive either atezolizumab (800 mg intravenously every 2 weeks up to 1 year) plus mDCF (eight cycles of 40 mg per m2 docetaxel and 40 mg per m2 cisplatin on day 1 and 1200 mg per m2 per day of fluorouracil for 2 days, every 2 weeks intravenously; group A) or mDCF alone (group B). Randomisation was done centrally using a minimisation technique and was stratified by age (<65 years vs ≥65 years) and disease status. The primary endpoint was investigator-assessed 12-month progression-free survival in the modified intention-to-treat population in group A (35% for the null hypothesis and 50% for the alternative hypothesis). This trial is registered with ClinicalTrials.gov, NCT03519295, and is closed to new participants.

FINDINGS

97 evaluable participants (64 in group A and 33 in group B) were enrolled between July 3, 2018, and Aug 19, 2020. The median follow-up was 26·5 months (95% CI 24·8-28·4). The median age of participants was 64·1 years (IQR 56·2-71·6), and 71 (73%) were female. 12-month progression-free survival was 45% (90% CI 35-55) in group A and 43% (29-58) in group B. In participants with a PD-L1 combined positive score of 5 or greater, 12-month progression-free survival was 70% (95% CI 47-100) in group A and 40% (19-85) in group B (interaction p=0·051) Both groups showed high compliance. Adverse events of grade 3 or higher were observed in 39 (61%) participants in group A and 14 (42%) in group B. The most common grade 3-4 adverse events were neutropenia (nine [14%] participants in group A vs five [15%] in group B), anaemia (nine [14%] vs one [3%]), fatigue (three [5%] vs four [12%]), and diarrhoea (seven [11%] vs one [3%]). Serious adverse events occurred in 16 (25%) participants in group A and four (12%) in group B, and these were mDCF-related in seven (11%) participants in group A and four (12%) in group B. Atezolizumab-related serious adverse events occurred in nine (14%) participants in group A, including grade 2 infusion-related reaction in three (5%), grade 3 infection in two (3%), and grade 2 colitis, grade 3 acute kidney injury, grade 3 sarcoidosis, and a grade 4 platelet count decrease each in one participant (2%). There were no treatment-related deaths.

INTERPRETATION

Despite a higher incidence of adverse events, combining atezolizumab with mDCF is feasible, with similar dose intensity in both groups, although the primary efficacy endpoint was not met. The predictive value of a PD-L1 combined positive score of 5 or greater now needs to be confirmed in future studies.

FUNDING

GERCOR, Roche.

[Immunotherapy for gastrointestinal cancer]

Cancers of gastrointestinal tract make up the largest group of solid tumour diseases in Germany. The prognosis at diagnosis is often critical. Drug therapies reduce the risk of relapse after resection and can halt the progression of metastatic disease. Immunotherapies contribute increasingly to the treatment of gastrointestinal tumours. Monoclonal antibodies (mAB) against surface receptors from the epidermal growth factor receptor family (EGFR, Her2) are well established. The effect is partly based on the interruption of the oncogenic downstream signalling cascades and partly on immune effector mechanisms such as antibody-dependent cellular cytotoxicity. In clinical practice mAB directed against programmed cell death protein 1 (PD-1), its ligand (PD-L1) and cytotoxic T-lymphocyte-associated protein-4 (CTLA-4) - so-called immune checkpoint inhibitors - play an increasing role and change the natural history of some subgroups of gastrointestinal cancers, especially those with deficient DNA mismatch repair which leads to genomic microsatellite instability.

MRI morphological characteristics of lymph nodes in anal squamous cell carcinoma

OBJECTIVES

Pre-treatment staging of anal squamous cell carcinoma (ASCC) includes pelvic MRI and [18F]-fluorodeoxyglucose positron emission tomography with computed tomography (PET-CT). MRI criteria to define lymph node metastases (LNMs) in ASCC are currently lacking. The aim of this study was to describe the morphological characteristics of lymph nodes (LNs) on MRI in ASCC patients with PET-CT-positive LNs.

METHODS

ASCC patients treated at Skåne University Hospital between 2009 and 2017 were eligible for inclusion if at least one positive LN according to PET-CT and a pre-treatment MRI were present. All PET-CT-positive LNs and PET-CT-negative LNs were retrospectively identified on baseline MRI. Each LN was independently classified according to pre-determined morphological characteristics by two radiologists blinded to clinical patient information.

RESULTS

Sixty-seven ASCC patients were included, with a total of 181 PET-CT-positive LNs identified on baseline MRI with a median short-axis diameter of 9.0 mm (range 7.5-12 mm). MRI morphological characteristics of PET-CT-positive LNs included regular contour (87%), round shape (89%), and homogeneous signal intensity on T2-weighed images (67%). An additional 78 PET-CT-negative LNs were identified on MRI. These 78 LNs had a median size of 6.8 mm (range 5.5-8.0 mm). The majority of PET-CT-negative LNs had a regular contour, round shape, and a homogeneous signal that was congruent to the primary tumor.

CONCLUSIONS

There are MRI-specific morphological characteristics for pelvic LNs in ASCC. PET-CT-positive and negative LNs share similar morphological features apart from size, with PET-CT-positive LNs being significantly larger. Further studies are needed to determine discrimination criteria for LNM in ASCC.

ROAR-A: re-optimization based Online Adaptive Radiotherapy of anal cancer, a prospective phase II trial protocol

BACKGROUND

Chemo-radiotherapy with curative intent for anal cancer has high complete remission rates, but acute treatment-related gastrointestinal (GI) toxicity is significant. Toxicity occurs due to irradiation of surrounding normal tissue. Current radiotherapy requires the addition of large planning margins to the radiation field to ensure target coverage regardless of the considerable organ motion in the pelvic region. This increases the irradiated volume and radiation dose to the surrounding normal tissue and thereby toxicity. Online adaptive radiotherapy uses artificial intelligence to adjust the treatment to the anatomy of the day. This allows for the reduction of planning margins, minimizing the irradiated volume and thereby radiation to the surrounding normal tissue.This study examines if cone beam computed tomography (CBCT)-guided oART with daily automated treatment re-planning can reduce acute gastrointestinal toxicity in patients with anal cancer.

METHODS/DESIGN

The study is a prospective, single-arm, phase II trial conducted at Copenhagen University Hospital, Herlev and Gentofte, Denmark. 205 patients with local only or locally advanced anal cancer, referred for radiotherapy with or without chemotherapy with curative intent, are planned for inclusion. Toxicity and quality of life are reported with Common Terminology Criteria of Adverse Events and patient-reported outcome questionnaires, before, during, and after treatment. The primary endpoint is a reduction in the incidence of acute treatment-related grade ≥ 2 diarrhea from 36 to 25% after daily online adaptive radiotherapy compared to standard radiotherapy. Secondary endpoints include all acute and late toxicity, overall survival, and reduction in treatment interruptions.

RESULTS

Accrual began in January 2022 and is expected to finish in January 2026. Primary endpoint results are expected to be available in April 2026.

DISCUSSION

This is the first study utilizing online adaptive radiotherapy to treat anal cancer. We hope to determine whether there is a clinical benefit for the patients, with significant reductions in acute GI toxicity without compromising treatment efficacy.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT05438836. Danish Ethical Committee: H-21028093.

Systematic review of survival following liver or lung metastasectomy for metastatic anal squamous cell carcinoma

INTRODUCTION

Metastatic anal squamous cell carcinoma (SCC) carries a poor prognosis and the evidence base for surgical resection of metastases remains limited. The aim of this study was to establish the survival outcomes for patients undergoing metastasectomy for anal SCC.

METHODS

A systematic review was performed using the MEDLINE®, Embase®, Cochrane and PubMed® databases. Studies were considered for inclusion in the review if they involved patients aged >18 years with a diagnosis of stage IV anal SCC who underwent metastasectomy for liver and/or lung metastases. The primary outcome measure was overall survival. Secondary outcome measures were disease free survival, early morbidity according to the Clavien-Dindo classification and quality of life, measured using a validated scoring tool. Risk of bias was assessed with the ROBINS-I (Risk Of Bias In Non-randomised Studies - of Interventions) tool.

RESULTS

There were 10 studies with a total of 98 patients. There was heterogeneity in results reporting, with recurrence free survival the most reported outcome. For all studies reporting on liver metastasectomy, the one-year overall survival rate was 87%. In studies with adequate follow-up reported, the three and five-year overall survival rates were 53% and 38% respectively. Only one study reported on lung metastasectomy patients; the overall median survival was 24 months. None of the studies reported on quality of life measures. The ROBINS-I tool identified a critical risk of bias in six studies, a serious risk in one study and a moderate risk in three studies.

CONCLUSIONS

The evidence base for metastasectomy in metastatic anal SCC is limited. Further information is required to inform future treatment methods and use of a standardised outcomes reporting method is needed to support this.

A comprehensive review of anal cancer-with a special focus on anal cytology

The diagnosis of anal cancer is relatively uncommon, but its incidence has been steadily increasing in high-risk populations. In the 2001 Bethesda System for Reporting Cervical Cytology, anal cytology was introduced as a component. Since then, it has been recognized as a potential tool for screening anal cancer, often in conjunction with high-resolution anoscopy. There are notable similarities between anal cancer and cervical cancer, including the causative role of human papillomavirus. However, there are also significant differences, particularly in terms of disease prevalence. Anal cytology may be used as a primary screening test, and in the event of abnormalities, patients are subsequently directed for high-resolution anoscopy. However, the best approach for anal cancer screening is yet to be determined and uniformly implemented. This comprehensive review article provides an in-depth analysis of the epidemiology and incidence of anal precursor and malignant lesions. It explores the various methods of sample procurement, preparation, interpretation (including sensitivity and specificity), and reporting terminology in anal cytology. The article also addresses the significance of concurrent high-risk human papillomavirus screening in anal cytology and its role in screening programs. Furthermore, it discusses the follow-up, prevention, and subsequent management strategies for anal cancers. By synthesizing current knowledge in these areas, this review aims to provide a comprehensive understanding of anal cytology and its implications in the early detection, prevention, and management of anal neoplasia and cancer.

Brachytherapy for rectal and anal cancer: Where are we and current perspectives?

Anal and rectal cancers were some of the first disease sites treated with brachytherapy due to the anatomic ease of implantation. As external beam radiotherapy grew in popularity the use of ano-rectal brachytherapy declined. However, the past few years have seen a steady resurgence in the use of brachytherapy in the ano-rectum supported by the use of large clinical series and randomized trials. The increasing acceptance by the surgical community of organ preservation as a valid treatment strategy for rectal cancer has encouraged the use of nonsurgical approaches and brachytherapy has shown itself to be a valuable tool for this. The current role of anal and rectal brachytherapy is presented with perspectives on its future use.

Unraveling Emerging Anal Cancer Clinical Biomarkers from Current Immuno-Oncogenomics Advances

Anal squamous cell carcinoma (ASCC) is a rare gastrointestinal malignancy associated with high-risk human papillomavirus (HPV) and is currently one of the fastest-growing causes of cancer incidence and mortality in developed countries. Although next-generation sequencing technologies (NGS) have revolutionized cancer and immuno-genomic research in various tumor types, a limited amount of clinical research has been developed to investigate the expression and the functional characterization of genomic data in ASCC. Herein, we comprehensively assess recent advancements in "omics" research, including a systematic analysis of genome-based studies, aiming to identify the most relevant ASCC cancer driver gene expressions and their associated signaling pathways. We also highlight the most significant biomarkers associated with anal cancer progression, gene expression of potential diagnostic biomarkers, expression of therapeutic drug targets, and emerging treatment opportunities. This review stresses the urgent need for developing target-specific therapies in ASCC. By illuminating the molecular characteristics and drug-target expression in ASCC, this study aims to provide insights for the development of precision medicine in anal cancer.

Management of non-metastatic anal cancer in the elderly: ancillary study of the French multicenter prospective cohort FFCD-ANABASE

BACKGROUND

Standard care for non-metastatic squamous cell carcinoma of the anus (SCCA) is chemoradiotherapy, data about elderly patients are scarce.

METHODS

All consecutive patients treated for non-metastatic SCCA from the French multicenter FFCD-ANABASE cohort were included. Two groups were defined according to age: elderly (≥75 years) and non-elderly (<75).

RESULTS

Of 1015 patients, 202 (19.9%) were included in the elderly group; median follow-up was 35.5 months. Among the elderly, there were more women (p = 0.015); frailer patients (p < 0.001), fewer smokers (p < 0.001) and fewer HIV-infected (p < 0.001) than in the non-elderly group. Concomitant chemotherapy and inguinal irradiation were less frequent (p < 0.001 and p = 0.04). In the elderly group; 3-year overall survival (OS), recurrence-free survival (RFS) and colostomy-free survival (CFS) were 82.9%, 72.4% and 78.0%, respectively; complete response rate at 4-6 months was 70.3%. There were no differences between groups for all outcomes and toxicity. In multivariate analyses for the elderly, PS ≥ 2 and locally-advanced tumors were significantly associated with poor OS (HR = 3.4 and HR = 2.80), RFS (HR = 2.4 and HR = 3.1) and CFS (HR = 3.8 and HR = 3.0); and treatment interruption with poor RFS (HR = 1.9).

CONCLUSION

In the FFCD-ANABASE cohort, age did not influence tumor and tolerance outcomes of non-metastatic SCCA. Optimal curative treatment should be offered to elderly patients.

Radiation therapy of the primary tumour and/or metastases of digestive metastatic cancers

Metastatic gastrointestinal cancer is not an uncommon situation, especially for pancreatic, gastric, and colorectal cancers. In this setting, few data are available on the impact of the treatment of the primary tumour. Oligometastatic disease is associated with longer survival in comparison with more advanced disease. Metastasis-directed therapy, such as stereotactic body radiotherapy, seems related to better outcomes, but the level of evidence is low. In most tumour locations, prospective data are very scarce and inclusion in ongoing trials is strongly recommended.

Pathogenic alterations in PIK3CA and KMT2C are frequent and independent prognostic factors in anal squamous cell carcinoma treated with salvage abdominoperineal resection

The management of anal squamous cell carcinoma (ASCC) has yet to experience the transformative impact of precision medicine. Conducting genomic analyses may uncover novel prognostic biomarkers and offer potential directions for the development of targeted therapies. To that end, we assessed the prognostic and theragnostic implications of pathogenic variants identified in 571 cancer-related genes from surgical samples collected from a homogeneous, multicentric French cohort of 158 ASCC patients who underwent abdominoperineal resection treatment. Alterations in PI3K/AKT/mTOR, chromatin remodeling, and Notch pathways were frequent in HPV-positive tumors, while HPV-negative tumors often harbored variants in cell cycle regulation and genome integrity maintenance genes (e.g., frequent TP53 and TERT promoter mutations). In patients with HPV-positive tumors, KMT2C and PIK3CA exon 9/20 pathogenic variants were associated with worse overall survival in multivariate analysis (Hazard ratio (HR)KMT2C  = 2.54, 95%CI = [1.25,5.17], P value = .010; HRPIK3CA  = 2.43, 95%CI = [1.3,4.56], P value = .006). Alterations with theragnostic value in another cancer type was detected in 43% of patients. These results suggest that PIK3CA and KMT2C pathogenic variants are independent prognostic factors in patients with ASCC with HPV-positive tumors treated by abdominoperineal resection. And, importantly, the high prevalence of alterations bearing potential theragnostic value strongly supports the use of genomic profiling to allow patient enrollment in precision medicine clinical trials.

Progress in the treatment of anal cancer: an overview of the latest investigational drugs

INTRODUCTION

Anal cancer, a rare malignancy accounting for 2.5-3.0% of gastrointestinal cancers, primarily manifests as squamous cell carcinoma associated with HPV. Recent years have witnessed significant advancements in managing squamous cell carcinoma of the anus (SCCA), particularly with the introduction of immune checkpoint inhibitors (ICIs) and randomized data on front-line chemotherapy.

AREAS COVERED

This review discusses the current standard treatments for both early and advanced SCCA, based on published data. The authors then describe the new approaches, focusing on ICI combinations, targeted agents, T-cell adoptive therapy, and HPV-therapeutic vaccines.

EXPERT OPINION

The current standard treatment for SCCA includes front-line carboplatin and paclitaxel, with pembrolizumab and nivolumab as later-line options. While modified DCF has shown promise in single-arm studies, its role as a front-line therapy requires confirmation through randomized data. We eagerly anticipate the results of phase 3 trials investigating the front-line chemo-immunotherapy for metastatic SCCA and ICI consolidation following chemoradiation for early-stage SCCA. Novel approaches like T-cell adoptive therapy, HPV-therapeutic vaccines, and bifunctional antibodies combined with HPV vaccines are in early-stage trials for HPV-mediated tumors, including HPV-positive SCCA. These approaches targeting HPV epitopes may eventually gain tumor-agnostic approval, although their role in SCCA may take time to establish.

Association of the pathomics-collagen signature with lymph node metastasis in colorectal cancer: a retrospective multicenter study

BACKGROUND

Lymph node metastasis (LNM) is a prognostic biomarker and affects therapeutic selection in colorectal cancer (CRC). Current evaluation methods are not adequate for estimating LNM in CRC. H&E images contain much pathological information, and collagen also affects the biological behavior of tumor cells. Hence, the objective of the study is to investigate whether a fully quantitative pathomics-collagen signature (PCS) in the tumor microenvironment can be used to predict LNM.

METHODS

Patients with histologically confirmed stage I-III CRC who underwent radical surgery were included in the training cohort (n = 329), the internal validation cohort (n = 329), and the external validation cohort (n = 315). Fully quantitative pathomics features and collagen features were extracted from digital H&E images and multiphoton images of specimens, respectively. LASSO regression was utilized to develop the PCS. Then, a PCS-nomogram was constructed incorporating the PCS and clinicopathological predictors for estimating LNM in the training cohort. The performance of the PCS-nomogram was evaluated via calibration, discrimination, and clinical usefulness. Furthermore, the PCS-nomogram was tested in internal and external validation cohorts.

RESULTS

By LASSO regression, the PCS was developed based on 11 pathomics and 9 collagen features. A significant association was found between the PCS and LNM in the three cohorts (P < 0.001). Then, the PCS-nomogram based on PCS, preoperative CEA level, lymphadenectasis on CT, venous emboli and/or lymphatic invasion and/or perineural invasion (VELIPI), and pT stage achieved AUROCs of 0.939, 0.895, and 0.893 in the three cohorts. The calibration curves identified good agreement between the nomogram-predicted and actual outcomes. Decision curve analysis indicated that the PCS-nomogram was clinically useful. Moreover, the PCS was still an independent predictor of LNM at station Nos. 1, 2, and 3. The PCS nomogram displayed AUROCs of 0.849-0.939 for the training cohort, 0.837-0.902 for the internal validation cohort, and 0.851-0.895 for the external validation cohorts in the three nodal stations.

CONCLUSIONS

This study proposed that PCS integrating pathomics and collagen features was significantly associated with LNM, and the PCS-nomogram has the potential to be a useful tool for predicting individual LNM in CRC patients.

Patient reported long-term side effects on bowel function and anal pain in anal cancer survivors - 3- and 6-year results from the Swedish national ANCA study

AIM

The primary therapeutic option for anal cancer treatment is chemoradiotherapy resulting in 80% survival. The aim of this study was to assess long-term bowel function impairment and anal pain at 3 and 6 years after anal cancer diagnosis, based on a hypothesis of an increase in impairment over time. A secondary aim was to investigate if chemoradiotherapy increased the risk for bowel impairment, compared to radiotherapy alone.

METHOD

The ANal CAncer study (ANCA) consists of a national Swedish cohort of patients diagnosed with anal cancer between 2011-2013. Patients within the study were invited to respond to a study-specific questionnaire at 3- and 6-years after diagnosis. Descriptive analyses for the primary endpoint and ordinal logistic regressions for secondary endpoint were performed.

RESULTS

A total of 388 patients (84%) were included in the study. At 3 years of follow-up, 264 patients were alive. A total of 195 of these patients (74%) answered a study specific questionnaire, and at 6 years 154 patients (67%). Fifty-seven percent experienced bowel urgency at both 3 and 6 years. There was an increased risk for repeated bowel movement within 1 h (OR 2.44 [95% CI: 1.08-5.61, p = 0.03]) at 3 years in patients who had been treated by chemoradiation compared to radiotherapy alone.

CONCLUSIONS

Impairment in bowel function and anal pain after anal cancer treatment should be expected and remains after 6 years. This suggests that long-term follow-up may be necessary in some form after customary follow-up. The addition of chemotherapy increases long-term side effects of bowel function.

Magnetic resonance imaging of anal cancer: tumor characteristics and early prediction of treatment outcome

PURPOSE

To analyze tumor characteristics derived from pelvic magnetic resonance imaging (MRI) of patients with squamous cell carcinoma of the anus (SCCA) before and during chemoradiotherapy (CRT), and to compare the changes in these characteristics between scans of responders vs. nonresponders to CRT.

METHODS

We included 52 patients with a pelvic 3T MRI scan prior to CRT (baseline scan); 39 of these patients received an additional scan during week 2 of CRT (second scan). Volume, diameter, extramural tumor depth (EMTD), and external anal sphincter infiltration (EASI) of the tumor were assessed. Mean, kurtosis, skewness, standard deviation (SD), and entropy values were extracted from apparent diffusion coefficient (ADC) histograms. The main outcome was locoregional treatment failure. Correlations were evaluated with Wilcoxon's signed rank-sum test and Pearson's correlation coefficient, quantile regression, univariate logistic regression, and area under the ROC curve (AUC) analyses.

RESULTS

In isolated analyses of the baseline and second MRI scans, none of the characteristics were associated with outcome. Comparison between the scans showed significant changes in several characteristics: volume, diameter, EMTD, and ADC skewness decreased in the second scan, although the mean ADC increased. Small decreases in volume and diameter were associated with treatment failure, and these variables had the highest AUC values (0.73 and 0.76, respectively) among the analyzed characteristics.

CONCLUSION

Changes in tumor volume and diameter in an early scan during CRT could represent easily assessable imaging-based biomarkers to eliminate the need for analysis of more complex MRI characteristics.

Nodal Elective Volume Selection and Definition during Radiation Therapy for Early Stage (T1-T2 N0 M0) Perianal Squamous Cell Carcinoma: A Narrative Clinical Review and Critical Appraisal

Distinction between anal canal and perianal squamous cell carcinomas (pSCCs) is essential, as these two subgroups have different anatomical, histological, and lymphatic drainage features. Early-stage true perianal tumors are very uncommon and have been rarely included in clinical trials. Perianal skin cancers and aCCs are included in the same tumor classification, even though they have different lymphatic drainage features. Furthermore, pSCCs are treated similarly to carcinomas originating from the anal canal. Radiation therapy (RT) is an essential treatment for anal canal tumors. Guidelines do not differentiate between treatment volumes for perianal tumors and anal cancers. So far, in pSCC, no study has considered modulating treatment volume selection according to the stage of the disease. We conducted a narrative literature review to describe the sites at higher risk for microscopic disease in patients with early-stage perianal cancers (T1-T2 N0 M0) to propose a well-thought selection of RT elective volumes.

Immune-checkpoint inhibitors in anal squamous cell carcinoma: a systematic review and meta-analysis

INTRODUCTION

Squamous cell carcinoma of the anus (SCCA) is a rare tumor. While most patients with locally advanced disease are cured with chemo-radiotherapy, about a quarter eventually experience metastatic recurrence. Standard treatment for advanced disease is chemotherapy, but recently evidence on the activity of immunotherapy has been reported. We performed a systematic review and meta-analysis of prospective trials testing immune-checkpoint inhibitors (ICIs) in patients with SCCA.

OBJECTIVE

We aimed to evaluate the overall response rate (ORR) and the disease control rate (DCR) of ICIs in patients with advanced SCCA.

METHODS

We systematically searched PubMed, Embase, and Scopus, through December 31, 2022, for prospective trials assessing ICIs in patients with advanced SCCA. The primary and secondary endpoints were respectively ORR and DCR.

RESULTS

Six prospective trials were included in the analysis, one of which was randomized. Overall, seven treatment arms and 347 patients have been analyzed. Five treatment arms tested ICIs as monotherapy and two arms examined ICIs in combination with cetuximab and bevacizumab, respectively. The pooled ORR was 13% (95%CI, 10%-17%), with a DCR of 57% (95%CI, 40%-74%). Results did not change in a sensitivity analysis, which excluded the two treatment arms testing the combination of ICIs with other drugs.

CONCLUSIONS

The efficacy of ICIs in SCCAs is low. Combination strategies with targeted drugs or chemotherapy might represent a better therapeutic strategy for these patients. Further studies are awaited to identify resistance mechanisms to ICIs and optimize their efficacy.

PET/MRI in colorectal and anal cancers: an update

Positron emission tomography (PET) in the era of personalized medicine has a unique role in the management of oncological patients and offers several advantages over standard anatomical imaging. However, the role of molecular imaging in lower GI malignancies has historically been limited due to suboptimal anatomical evaluation on the accompanying CT, as well as significant physiological 18F-flurodeoxyglucose (FDG) uptake in the bowel. In the last decade, technological advancements have made whole-body FDG-PET/MRI a feasible alternative to PET/CT and MRI for lower GI malignancies. PET/MRI combines the advantages of molecular imaging with excellent soft tissue contrast resolution. Hence, it constitutes a unique opportunity to improve the imaging of these cancers. FDG-PET/MRI has a potential role in initial diagnosis, assessment of local treatment response, and evaluation for metastatic disease. In this article, we review the recent literature on FDG-PET/MRI for colorectal and anal cancers; provide an example whole-body FDG-PET/MRI protocol; highlight potential interpretive pitfalls; and provide recommendations on particular clinical scenarios in which FDG-PET/MRI is likely to be most beneficial for these cancer types.

Recent Advances in the Management of Anal Cancer

The incidence and mortality of squamous cell carcinoma of the anus (SCCA) is on the rise, which highlights the unmet need for advances in treatment options. The landscape of treatment for this cancer is rapidly evolving with novel combination strategies including immunotherapy, radiation therapy and biomarker-guided therapy. This review article features an overview of recent advancements in both locoregional and metastatic SCCA. The recent focus on locoregional SCCA management is to tailor treatment according to tumor burden and minimize treatment-related toxicities. Mitomycin plus either infusional 5-fluorouracil (5-FU) or capecitabine is used for first-line chemoradiotherapy (CRT), and intensity-modulated radiotherapy (IMRT) is the preferred modality for radiation for locoregional anal cancer. Locally recurrent disease is managed with surgical resection. Systemic treatment is first-line for metastatic SCCA and immunotherapy with nivolumab and pembrolizumab being included as second-line agents. Current and future clinical trials are evaluating treatments for SCCA including immunotherapy alone or in combination regimens, radiotherapies, targeted treatments and novel agents. Another critical aspect of current research in SCCA is the personalization of CRT and immunotherapies based on molecular characterization and biomarkers such as the programmed death-ligand 1 (PD-L1), epidermal growth factor receptor (EGFR) and circulating tumor DNA.

Diffusion-weighted imaging complements T2-weighted MRI for tumour response assessment in squamous anal carcinoma

OBJECTIVES

A published tumour regression grade (TRG) score for squamous anal carcinoma treated with definitive chemoradiotherapy based on T2-weighted MRI yields a high proportion of indeterminate responses (TRG-3). We investigate whether the addition of diffusion-weighted imaging (DWI) improves tumour response assessment in the early post treatment period.

MATERIALS AND METHODS

This retrospective observational study included squamous anal carcinoma patients undergoing MRI before and within 3 months of completing chemoradiotherapy from 2009 to 2020. Four independent radiologists (1-20 years' experience) scored MRI studies using a 5-point TRG system (1 = complete response; 5 = no response) based on T2-weighted sequences alone, and then after a 12-week washout period, using a 5-point DWI-TRG system based on T2-weighted and DWI. Scoring confidence was recorded on a 5-point scale (1 = low; 5 = high) for each reading and compared using the Wilcoxon test. Indeterminate scores (TRG-3) from each reading session were compared using the McNemar test. Interobserver agreement was assessed using kappa statistics.

RESULTS

Eighty-five patients were included (mean age, 59 years ± 12 [SD]; 55 women). T2-weighted TRG-3 scores from all readers combined halved from 24% (82/340) to 12% (41/340) with DWI (p < 0.001). TRG-3 scores changed most frequently (41%, 34/82) to DWI-TRG-2 (excellent response). Complete tumour response was recorded clinically in 77/85 patients (91%). Scoring confidence increased using DWI (p < 0.001), with scores of 4 or 5 in 84% (287/340). Interobserver agreement remained fair to moderate (kappa range, 0.28-0.58).

CONCLUSION

DWI complements T2-weighted MRI by reducing the number of indeterminate tumour responses (TRG-3). DWI increases radiologist's scoring confidence.

CLINICAL RELEVANCE STATEMENT

Diffusion-weighted imaging improves T2-weighted tumour response assessment in squamous anal cancer, halving the number of indeterminate responses in the early post treatment period, and increases radiologists' confidence.

KEY POINTS

Tumour response based on T2-weighted MRI is often indeterminate in squamous anal carcinoma. Diffusion-weighted imaging alongside T2-weighted MRI halved indeterminate tumour regression grade scores assigned by four radiologists from 24 to 12%. Scoring confidence of expert and non-expert radiologists increased with the inclusion of diffusion-weighted imaging.

A common [18F]-FDG PET radiomic signature to predict survival in patients with HPV-induced cancers

Locally advanced cervical cancer (LACC) and anal and oropharyngeal squamous cell carcinoma (ASCC and OPSCC) are mostly caused by oncogenic human papillomaviruses (HPV). In this paper, we developed machine learning (ML) models based on clinical, biological, and radiomic features extracted from pre-treatment fluorine-18-fluorodeoxyglucose positron emission tomography ([18F]-FDG PET) images to predict the survival of patients with HPV-induced cancers. For this purpose, cohorts from five institutions were used: two cohorts of patients treated for LACC including 104 patients from Gustave Roussy Campus Cancer (Center 1) and 90 patients from Leeds Teaching Hospitals NHS Trust (Center 2), two datasets of patients treated for ASCC composed of 66 patients from Institut du Cancer de Montpellier (Center 3) and 67 patients from Oslo University Hospital (Center 4), and one dataset of 45 OPSCC patients from the University Hospital of Zurich (Center 5). Radiomic features were extracted from baseline [18F]-FDG PET images. The ComBat technique was applied to mitigate intra-scanner variability. A modified consensus nested cross-validation for feature selection and hyperparameter tuning was applied on four ML models to predict progression-free survival (PFS) and overall survival (OS) using harmonized imaging features and/or clinical and biological variables as inputs. Each model was trained and optimized on Center 1 and Center 3 cohorts and tested on Center 2, Center 4, and Center 5 cohorts. The radiomic-based CoxNet model achieved C-index values of 0.75 and 0.78 for PFS and 0.76, 0.74, and 0.75 for OS on the test sets. Radiomic feature-based models had superior performance compared to the bioclinical ones, and combining radiomic and bioclinical variables did not improve the performances. Metabolic tumor volume (MTV)-based models obtained lower C-index values for a majority of the tested configurations but quite equivalent performance in terms of time-dependent AUCs (td-AUC). The results demonstrate the possibility of identifying common PET-based image signatures for predicting the response of patients with induced HPV pathology, validated on multi-center multiconstructor data.

Clinical and oncological outcomes of pelvic exenteration surgery for anal squamous cell carcinoma

AIM

Anal cancer incidence and mortality rates are rising in the United Kingdom (UK). Surgery is an important treatment modality for persistent or recurrent disease. There is a paucity of data on outcomes for patients undergoing pelvic exenteration for anal squamous cell carcinoma (SCC) for persistent or recurrent disease. The aim of this study was to investigate the outcomes for patients who were treated with pelvic exenteration for anal SCC from two high-volume, high-complexity pelvic exenteration units in the UK.

METHOD

A retrospective review of prospectively maintained databases from 2011 to 2020 was undertaken. Primary endpoints included R0 resection rates, overall and disease-free survival at 2 and 5 years.

RESULTS

From 2011 to 2020, 35 patients with anal SCC were selected for exenteration. An R0 resection was achieved in 26 patients (77%). Of the remaining patients, seven patients had an R1 resection and one had a R2 resection. One further patient was excluded from additional analysis as the disease was inoperable at the time of laparotomy. With a median follow-up of 19.5 months (interquartile range 7.9-53.5 months), overall survival was 50% (17/34). Patients with an R1/2 resection had a significantly poorer overall survival [0.27 (0.09-0.76), p = 0.021] than those patients in whom R0 resection was achieved. Disease-free survival was 38.2% (13/34) and an R1/R2 resection was associated with a significantly reduced disease-free survival [0.12 (0.04-0.36), p < 0.001].

CONCLUSION

Complete R0 resection for recurrent or persistent anal SCC is possible in the majority of patients and improves overall and disease-free survival compared with R1/R2 resection.

Predictors of recurrence following local excision for early-stage anal squamous cell carcinoma

INTRODUCTION

There is increasing use of local excision (LE) for definitive treatment of early-stage anal squamous cell carcinoma (ASCC) to avoid the morbidity associated with chemoradiotherapy (CRT). However, the importance of different histological variables on risk of recurrence is poorly understood.

METHODS

A detailed analysis of patient characteristics, histology results, recurrence patterns and salvage treatment was conducted in consecutive T1/T2N0 ASCC patients treated by LE 2010-2021 across a UK regional cancer network multi-disciplinary team (MDT). Associations between potential predictors of disease recurrence were explored using chi-squared and Kruskal-Wallis tests for categorical and continuous variables respectively.

RESULTS

Of 621 ASCC patients discussed in the network MDT, 164 had early-stage disease (T1/T2 N0). Of these, 36 (22%) were deemed suitable for LE (median age 61 years, female to male ratio 2:1). Twenty-two LE tumours were T1; 14 were T2. There were 12 well-differentiated tumours, 21 moderate and 3 poorly-differentiated. Seven out of 36 LE patients (19.4%) developed recurrence, all of whom went on to have salvage treatment with CRT (n = 4), re-excision (n = 2) or radiotherapy (n = 1). Predictors of disease recurrence following LE were: tumour differentiation (p = 0.024), tumour depth (p = 0.033) and R1 resection margin (p = 0.034). Tumour stage and site (margin/canal) were non-significant.

CONCLUSION

LE for T1/T2 N0 ASCC of the margin or canal is a viable treatment strategy to avoid the morbidity associated with CRT and salvage treatments are still available for patients that develop recurrence. Tumour differentiation, depth and margin status are all important factors to consider when discussing management of early-stage ASCC.

Prognostic impact of post-treatment FDG PET/CT in anal canal cancer: A prospective study

BACKGROUND AND PURPOSE

The aim of our prospective study was to assess the prognostic value of 18F-FDG PET/CT performed two months post treatment for anal canal neoplasm.

POPULATION AND METHODS

Consecutive patients with histologically proved anal cancer, with 18F-FDG PET/CT pre and two months post treatment were included. Patients were not previously treated for this neoplasm and then received radiotherapy ± chemotherapy. Clinical and pathologic data were collected and for 18F-FDG PET/CT visual and quantitative analysis (standardized uptake value, metabolic volume) were performed; response was classified according to EORTC and PERCIST criteria. The results were assessed for disease free survival and local recurrence free survival using the log-Rank test RESULTS: From December 2014 to September 2019, 94 consecutive patients were screened and 78 were included in this study. Median follow-up was 51 months. Two months post treatment, 37 patients (47.4%) had a complete radiological response according to both EORTC and PERCIST criteria, 66 patients (84.6%) had a clinical complete response. For disease free survival, the prognostic value of complete response was statistically significant (p=0.02) with 18F-FDG PET/CT and with clinical examination (p<0.001). For local recurrence free survival, the prognostic value with 18F-FDG PET/CT was lower (p=0.04) than clinical examination (p < 0.007).

CONCLUSION

While clinical examination remains the gold standard for post treatment evaluation in anal cancer, 18F-FDG PET/CT has a statistically significant prognostic value. These two assessments could be combined to improve early evaluation.

Case Report: Resolution of high grade anal squamous intraepithelial lesion with antibiotics proposes a new role for syphilitic infection in potentiation of HPV-associated ASCC

Introduction

Human Papillomavirus (HPV) is the primary risk factor for the development of anal intraepithelial neoplasia (AIN) and is a leading risk factor for anogenital squamous cell carcinoma (ASCC). Despite common shared risk factors for both HPV and syphilis, co-infection is not well documented, and the role of syphilitic infection in HPV-associated AIN and ASCC potentiation is not defined.

Case description/methods

A 72-year-old single male presented with complaints of mild rectal pain and intermittent rectal bleeding. A flexible sigmoidoscopy was performed, and a firm 4.5cm x 3cm perianal mass was detected and superficially biopsied. Pathology findings demonstrated evidence of a high grade squamous intraepithelial lesion (HGSIL, AIN II/III/AIS) with viral cytopathic effect, consistent with HPV infection. Much of the biopsied lesion showed acanthotic squamous mucosa with intraepithelial neutrophils and abundant submucosal plasma cells, suggesting possible syphilitic involvement. Subsequent immunohistochemical staining for p16 as a surrogate marker for HPV was positive, as was an immunohistochemical stain for spirochetes, supportive of co-infection with Treponema pallidum pallidum (T. pallidum), the causative agent in venereal syphilis. The patient was referred to an infectious disease specialist for syphilitic infection and was treated with penicillin with surprisingly complete resolution of the lesion. EUAs were performed 2- and 3-months following treatment without lesion recurrence. However, one year following diagnosis, a flexible sigmoidoscopy revealed a 5 mm recurrent HPV-related low-grade AIN 1 lesion at the dentate line.

Discussion

Resolution of the lesion by antibiotic treatment for syphilitic infection suggested that co-infection by T. pallidum may potentiate HPV-associated squamous cell carcinoma based on histological findings. Findings from this case, as well as a review of bacterial involvement and potentiation in various cancers, are reviewed here. Such findings offer new insight regarding the role of STI-associated bacteria and HPV co-infection in the establishment of AIN and may additionally propose new treatment modalities for ASCC.