Inguinal lymph node recurrence in the untreated groin of patients with anal carcinoma

Nordic anal cancer (NOAC) group consensus guidelines for risk-adapted delineation of the elective clinical target volume in anal cancer

Background: To date, anal cancer patients are treated with radiotherapy to similar volumes despite a marked difference in risk profile based on tumor location and stage. A more individualized approach to delineation of the elective clinical target volume (CTVe) could potentially provide better oncological outcomes as well as improved quality of life. The aim of the present work was to establish Nordic Anal Cancer (NOAC) group guidelines for delineation of the CTVe in anal cancer.Methods: First, 12 radiation oncologists reviewed the literature in one of the following four areas: (1) previous delineation guidelines; (2) patterns of recurrence; (3) anatomical studies; (4) common iliac and para-aortic recurrences and delineation guidelines. Second, areas of controversy were identified and discussed with the aim of reaching consensus.Results: We present consensus-based recommendations for CTVe delineation in anal cancer regarding (a) which regions to include, and (b) how the regions should be delineated. Some of our recommendations deviate from current international guidelines. For instance, the posterolateral part of the inguinal region is excluded, decreasing the volume of irradiated normal tissue. For the external iliac region and the cranial border of the CTVe, we agreed on specifying two different recommendations, both considered acceptable. One of these recommendations is novel and risk-adapted; the external iliac region is omitted for low-risk patients, and several different cranial borders are used depending on the individual level of risk.Conclusion: We present NOAC consensus guidelines for delineation of the CTVe in anal cancer, including a risk-adapted strategy.

Current treatment and future directions in the management of anal cancer

Although rare, the rate of squamous cell carcinoma of the anus (SCCA) is rising globally. Most patients present with nonmetastatic disease and are curable with appropriate treatment, which has evolved significantly over the last several decades. Before the 1970s, SCCA was managed with radical surgery, resulting in a permanent colostomy. Researchers found that preoperative treatment with chemotherapy and concurrent radiation could achieve a pathologic complete response. After this observation, definitive therapy shifted from radical surgery to sphincter-preserving chemoradiation. Investigations into the necessity of chemotherapy and the optimal regimen found that chemotherapy with mitomycin-C and 5-fluorouracil is required for cure. Further studies evaluating the addition of induction or maintenance chemotherapy, monoclonal antibody therapy, or higher radiation doses have demonstrated no significant benefit to disease control. Advanced radiation delivery with intensity-modulated radiotherapy techniques is now considered the standard of care because of its prospectively determined, favorable acute toxicity profile compared with 3-dimensional conformal radiation. It is important to note that chemoradiation treatment response may be slow (up to 26 weeks) and should be assessed through serial clinical examinations. Today, surgical management of SCCA is reserved only for the lowest risk, early stage tumors or for recurrent/persistent disease. Current studies are evaluating radiation dose de-escalation in early stage disease and radiation dose escalation and the addition of immune checkpoint inhibitors in locally advanced cancers. In reviewing how and why modern-day treatment of SCCA was established, the objective of this report is to reenforce adherence to current treatment paradigms to assure the best possible outcomes for patients.

Tailoring the radiotherapy approach in patients with anal squamous cell carcinoma based on inguinal sentinel lymph node biopsy

BACKGROUND AND OBJECTIVES

The aim of our study was to analyze the results of selective inguinal node irradiation in patients with anal cancer, based on the biopsy of the inguinal sentinel lymph node (SLN), in terms of local control and prognosis.

METHODS

Records of patients with anal squamous cell carcinoma from January 2001 to December 2016 were retrospectively reviewed. Tc99 lymphoscintigraphy was performed in all the clinically inguinal negative patients, followed by radio-guided surgical removal of the inguinal SLN. All patients were treated with combined radiochemotherapy. In patients with negative sentinel nodes, the inguinal area was excluded in the radiotherapy field.

RESULTS

A total of 123 patients, 76 females (61.8%), mean age 60.1 ± 12.19 years old, underwent intraoperative lymph node retrieval. The histological analysis showed metastasis in the SLN in 28 patients (22.8%). The mean follow-up was 43.44 ± 31.86 months. No inguinal recurrence was observed in patients with negative inguinal sentinel node(s). A statistically significant difference was observed for overall and disease-free survivals in a patient with positive and negative inguinal sentinel nodes.

CONCLUSIONS

In patients with anal canal cancer, the exclusion of the inguinal regions from the radiotherapy field, in patients with negative SLN, does not compromise locoregional control nor prognosis.

Impact of sentinel lymph-node biopsy and FDG-PET in staging and radiation treatment of anal cancer patients

To assess the role of sentinel lymph-node biopsy (SLNB) and FDG-PET in staging and radiation treatment (RT) of anal cancer patients. This retrospective study was performed on 80 patients (male: 32, female: 48) with a median age of 60 years (39-89 years) with anal squamous cell carcinoma who were treated from March 2008 to March 2018 at the IRCCS San Raffaele Hospital. Patients without clinical evidence of inguinal LNs metastases and/or with discordance between clinical evidence and imaging features were considered for SLNB. FDG-PET was performed in 69/80 patients. Patients with negative imaging in inguinal region and negative SLNB could avoid RT on groin to spare inguinal toxicity. CTV included GTV (primary tumour and positive LNs) and pelvic ± inguinal LNs. PTV1 and PTV2 corresponded to GTV and CTV, respectively, adding 0.5 cm. RT dose was 50.4 Gy/28 fractions to PTV2 and 64.8 Gy/36 fractions to PTV1, delivered with 3DCRT (n = 24) or IMRT (n = 56), concomitant to Mitomycin-C and 5-FU chemotherapy. FDG-PET showed inguinal uptake in 21/69 patients (30%) and was negative in 48/69 patients (70%). Lymphoscintigraphy was performed in 11/21 positive patients (4 patients SLNB confirmed inguinal metastases, 6 patients false positive and 1 patient SLN not found), and in 29/48 negative patients (5/29 showed metastases, 23/29 true negative and 1 SLN not found). Sensitivity, specificity, positive and negative predictive value of FDG-PET were 62%, 79%, 40% and 82%, respectively. Median follow-up time from diagnosis was 40.3 months (range: 4.6-136.4 months): 69 patients (86%) showed a complete response, 10 patients (13%) a partial response, 1 patient (1%) a stable disease. Patients treated on groin (n = 54) versus not treated (n = 26) showed more inguinal dermatitis (G1-G2: 50% vs. 12%; G3-G4: 17% vs. 0%, p < 0.05). For patients treated on groin, G3-G4 inguinal dermatitis, stomatitis and neutropenia were significantly reduced with IMRT against 3DCRT techniques (13% vs. 36%, p = 0.10; 3% vs. 36%, p = 0.003; 8% vs. 29%, p = 0.02, respectively). SLNB improves the FDG-PET inguinal LNs staging in guiding the decision to treat inguinal nodes. IMRT technique significantly reduced G3-G4 toxicities when patients are treated on groin.

Recurrent ilioinguinal lymph node metastasis from primary anal adenocarcinoma: what should we do?-A case report and review of literature

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Anal adenocarcinoma is more common in the Asian population than previously thought.

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Treatment of ilioinguinal lymph node metastasis from anal canal squamous cell carcinoma has been well described, but the management for primary adenocarcinoma is less so.

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Groin dissection for recurrent ilioinguinal lymph node metastasis from primary anal adenocarcinoma is a reasonable approach.

Introduction

Anal canal tumors are uncommon amongst gastrointestinal tumors or anorectal tumors. While the majority of them seem to be squamous cell carcinoma in nature, adenocarcinoma may be equally as common amongst the Asian population. Recurrent nodal metastasis from a primary anal malignancy is not a rare occurrence in view of the anatomy of the anal canal.

Case presentation

A 70 year-old patient underwent surgery for synchronous sigmoid and anal adenocarcinoma in 2015. He then re-presented 2 years later with recurrence in the right inguinal lymph nodes. He subsequently underwent a right ilio-inguinal lymph node block dissection with a Sartorius flap creation.

Discussion

As most anal canal tumors are squamous cell carcinomas, the optimal treatment for recurrent ilioinguinal lymph node disease has been well-established. This usually involves groin dissection as surgical treatment, with consideration for adjuvant combined chemoradiotherapy. Such an approach is likely to be beneficial for ilioinguinal lymph node disease from primary anal canal adenocarcinomas as well.

Conclusion

Physicians caring for patients with primary anal adenocarcinoma should be vigilant for possible ilioinguinal lymph node metastasis as this is not a rare occurrence. Surgical treatment appears to be a reasonable approach, with consideration for adjuvant therapy.

What factors are associated with the poor prognosis of anal adenocarcinoma compared with low-lying rectal adenocarcinoma based on a population analysis: A propensity score matching study

PURPOSE

Anal adenocarcinoma (AA) represents a rare condition, and little is known about the predictive factors of the outcomes or the optimal TNM staging system for curable AA. Using population-based data, we preliminarily sought to determine the prognostic factors and evaluate the existing T and N staging criteria of AA.

METHODS

We analyzed the Surveillance, Epidemiology, and End Results 18 database to identify patients 20-80 years old who were diagnosed with AA or rectal adenocarcinoma (RA) and underwent abdominal perineal resection between 2004 and 2012. The difference between Kaplan-Meier survival curves was estimated by a log-rank test. A Cox proportional hazard regression model was used to adjust the effects of other covariates on survival in the propensity score-matched cohort, including age, gender, race, marital status, histology, grade of differentiation, tumor size, number of positive lymph nodes, radiotherapy, and chemotherapy.

RESULTS

Compared to patients with RA, patients with AA had a worse CSS after controlling for other covariates (hazard ratio [HR], 1.96; 95% confidence interval [CI], 1.25-3.07; P<0.01). For AA, the increasing tumor size (2-5 cm: HR, 0.62; 95% CI, 0.29-1.32; P>0.05; >5 cm: HR, 1.01; 95% CI, 0.49-2.07; P>0.05) had no significant influence on survival. The number of positive lymph nodes (1-3: HR, 2.93; 95% CI, 1.55-5.53; P<0.01; ≥4: HR, 4.24; 95% CI, 2.08-8.62; P<0.01) significantly influenced survival.

CONCLUSIONS

AA confers a worse prognosis than RA does. The T staging criteria of anal carcinoma, dominated by tumor size, seem to be invalid for AA, while the number of positive lymph nodes is a prognostic factor.

Dosimetric comparison of different radiation techniques (IMRT vs. 3-dimensional) of the "true" (deep) ano-inguinal lymphatic drainage of anal cancer patients

Introduction

The ano-inguinal lymphatic drainage (AILD) is located in the subcutaneous adipose tissue of the proximal medial thigh. Currently, there are no recommendations for an inclusion of the ‘true’ AILD in the clinical target volume (CTV) of definitive chemoradiation for anal cancer patients. To estimate the relevance of inguinal recurrence, we compared the incidental dose to the AILD in anal cancer (AC) patients who were treated either with Volumetric Arc Therapy – Intensity Modulated Radiation Therapy (VMAT-IMRT) or conventional 3D-radiation technique.

Methods

One VMAT-IMRT-plans and one 3D-plans were calculated on the same target volumes and identical dose prescription in ten patients. We defined the volume of the AILD on the planning CT-scans based on the information of new fluorescence methods. Furthermore, we defined several anatomical subvolumes of interest inside the AILD. We examined and compared absolute and relative dosimetric parameters of the AILD and different anatomical subunits.

Results

The Dmean of the AILD was 40 Gy in the 3D-group and 38 Gy in the IMRT-group. Dmean and Dmedian as well as the V30Gy of the AILD and all subvolumes of the caudal AILD were significant higher using 3D-RT compared to IMRT. Even though the absolute differences were small, in the caudal aspect of the ano-inguinal lymphatic drainage the V30Gy could be more than 10% less with VMAT-IMRT.

Conclusions

3D-RT was slightly superior to IMRT in terms of dose coverage of the AILD. However, the absolute differences were very small. Some relevant caudal parts of the AILD received an insufficient dose for treating potential micrometastases. Particularly in high-risk situations, this may lead to inguinal recurrence and therefore the true deep AILD should be included into the target volume in high risk patients.

Dosimetric quantification of the incidental irradiation of the 'true' (deep) ano-inguinal lymphatic drainage of anal cancer patients not described in conventional contouring guidelines

INTRODUCTION

The ano-inguinal lymphatic drainage (AILD) is located in the subcutaneous adipose tissue of the proximal medial thigh. Findings from fluorescence methods give us new information about anatomical conditions of the AILD. Current contouring guidelines do not advise the inclusion of the 'true' AILD into the clinical target volume (CTV). Aim of this work was the retrospective analysis of the incidental dose to the AILD in an anal cancer (AC) patient cohort who underwent definitive chemoradiation (CRT) therapy with Volumetric Arc Therapy - Intensity Modulated Radiation Therapy (VMAT-IMRT).

METHODS

VMAT-IMRT plans of 15 AC patients were analyzed. Based on findings from new fluorescence methods we created a new volume, the expected AILD. The examined dosimetric parameters were the minimal, maximal and mean dose and V10-V50 that were delivered to the AILD, respectively.

RESULTS

The median volume of AILD was 1047 cm³. Mean D_min, D_max and D_mean were 7.5 Gy, 58.9 Gy and 40.8 Gy for AILD. The clinical relevant dose of 30.0 Gray covered in mean 76% of the volume of the AILD, respectively.

CONCLUSIONS

Only 76% of the AILD-volume received at least an expected required treatment dose of 30 Gy incidentally. Concerning the low number of loco-regional relapses in AC patients after definitive CRT one has to balance increased side effects against a rigid oncological-anatomical interpretation of the local lymphatic drainage by including the AILD into the standard CTV.

Radiotherapy for anal squamous cell carcinoma: must the upper pelvic nodes and the inguinal nodes be treated?

BACKGROUND

Loco-regional failure is the predominant cause of death in anal squamous cell carcinoma. We assessed patterns of loco-regional recurrence to determine the impact of radiotherapy (RT) volumes on patient outcome.

METHODS

Retrospective clinical study, including patients treated curatively with RT or chemo-radiotherapy between 1994 and 2007. RT fields/volumes were reviewed and compared with patterns of failure. Patients were classified as having whole pelvic radiotherapy (WPRT) if RT extended to L5/S1 or lower pelvic radiotherapy (LPRT) if it extended to the lower sacroiliac joints or below. Patients with negative inguinal nodes either underwent prophylactic inguinal radiotherapy (PIRT) or had inguinal observation (IO). Patterns of failure were compared.

RESULTS

Twenty-seven patients (53%) had WPRT and 24 (47%) had LPRT. Forty-two patients had negative inguinal nodes: 29 (69%) had PIRT and 13 (31%) had IO. Median follow-up was 5.8 years. Twelve regional failures occurred in eight patients: three pelvic, one inguinal and four pelvic and inguinal. All patients with regional failure died of disease. Pelvic nodal failure was 7.7% in N0 and 33% in N1-3 patients (P = 0.012). There was no difference in pelvic regional failure between WPRT and LPRT (11% versus 16%, P = 0.64). There was only one possible regional failure above LPRT in this group (4%). Inguinal failure was 0% in the PIRT group compared with 23% in IO group (P = 0.009).

CONCLUSION

There was no difference in pelvic regional failure between WPRT and LPRT. LPRT is likely to be safe in N0 patients. Inguinal nodes should be treated in all patients.

Anal adenocarcinoma requires prophylactic inguinal nodal treatment: Results from a single Chinese institution

Background: Literature pertaining to prophylactic inguinal nodal treatment for anal adenocarcinoma in China is scarce.

Methods: In this retrospective study, we analyzed 126 patients from 1965 to 2015. Among these, 67 patients received surgery only, 18 patients received chemoradiotherapy only, 27 patients received a combination of both, and the remaining 14 patients received palliative treatment.

Results: The median follow up period was 30 months. The 1-year, 3-year, and 5-year overall survival rates were 85.8%, 62.5%, and 43.4%, respectively. The 5-year overall survival was 46.9% for patients with negative inguinal lymph nodes and 19.1% for patients with positive inguinal lymph nodes (p=0.007). The overall 5-year inguinal node relapse-free survival was 83.0%. The 5-year inguinal node relapse-free survival was 87.5% for stage I, 86.9% for stage II, and 76.5% for stage III cancers. Among those with negative inguinal nodes, the 5-year inguinal node relapse-free survival was 85.7% for negative regional lymph nodes and 75.4% for positive regional lymph nodes (p=0.089).

Conclusion: Inguinal lymph node is a high-risk subclinical area. Prophylactic inguinal nodal treatment is necessary for patients with anal adenocarcinoma irrespective of positive or negative inguinal lymph nodes.

New developments in colorectal surgery

PURPOSE OF REVIEW

Surgical management of diseases of the colon and rectum continues to evolve. This review examines the recent publications that have led to or may lead to changes in practice in this field.

RECENT FINDINGS

We identified and reviewed the recent publications in the areas of colon, rectal, and anal cancers; inflammatory bowel disease; incontinence; diverticulitis; hemorrhoids; fistulas; and quality improvement initiatives.

SUMMARY

New technologies and novel questions have changed practice and will improve patient outcomes. Multiinstitutional studies, ideally randomized, continue to be essential to answer the questions that will lead to identification of best practices.

Is elective inguinal radiotherapy necessary for locally advanced rectal adenocarcinoma invading anal canal?

Background

We investigated whether routine elective irradiation of a clinically negative inguinal node (IGN) is necessary for patients with locally advanced distal rectal cancer and anal canal invasion (ACI).

Methods

We reviewed retrospectively 1,246 patients with locally advanced rectal adenocarcinoma managed using preoperative or postoperative chemoradiotherapy and radical surgery between 2001 and 2011. The patients’ IGN was clinically negative at presentation and IGN irradiation was not performed. ACI was defined as the lower edge of the tumor being within 3 cm of the anal verge. Patients were divided into two groups, those with ACI (n = 189, 15.2%) and without ACI (n = 1,057, 84.8%).

Results

The follow-up period was a median of 66 months (range, 3–142 months). Among the 1,246 patients, 10 developed IGN recurrence; 7 with ACI and 3 without ACI. The actuarial IGN recurrence rate at 5 years was 0.7%; 3.5% and 0.2% in patients with and without ACI, respectively (p < 0.001). Isolated IGN recurrence occurred in three patients, all of whom had ACI tumors. These three patients received curative intent local treatments, and one was alive with no evidence of disease 10 years after IGN recurrence. Salvage treatments in the other two patients controlled successfully the IGN recurrence for >5 years, but they developed second malignancy or pelvic and distant recurrences. Seven patients with non-isolated IGN recurrence died of disease at 5–22 months after IGN recurrence.

Conclusion

The low IGN recurrence rate even with ACI and the feasibility of salvage of isolated IGN recurrence indicated that routine elective IGN irradiation is not necessary for rectal cancer with ACI.