Anal neoplasms

Immune Checkpoint Blockade in Lower Gastrointestinal Cancers: A Systematic Review

BACKGROUND

Limited therapy options exist for patients with treatment-refractory metastatic colorectal or anal cancers, prompting investigation into alternative therapies. Immunotherapy in the form of immune checkpoint blockade is one such emerging treatment that has demonstrated promising results in other tumour streams.x This review aims to assess the current use of immune checkpoint blockade in patients with lower gastrointestinal tumours.

PATIENTS AND METHODS

Embase, Medline and Cochrane databases were searched for included studies. Clinical trials published in English and utilising immune checkpoint blockade for primary tumours situated in the lower gastrointestinal tract were included. Databases were searched for studies reporting on at least one of overall survival, progression-free survival or response to therapy.

RESULTS

In total, 972 abstracts were screened, with 10 studies included in the final review. Eight trials (833 patients) assessed immune checkpoint blockade in the setting of colorectal cancers. These included pembrolizumab, nivolumab, durvalumab, atezolizumab, tremelimumab and ipilimumab. A total of 20 patients across all studies achieved a complete response, and 111 patients achieved a partial response to treatment. Two trials (62 patients) assessed immune checkpoint blockade in anal cancer, utilising nivolumab and pembrolizumab. Two patients across both studies achieved a complete response, and 11 patients achieved a partial response.

CONCLUSIONS

A number of patients with advanced lower gastrointestinal tumours achieved a complete response to treatment for what would otherwise be considered palliative disease. Presented data have highlighted that particular patients may benefit from first-line or combination immunotherapy, and thus, further investigation is warranted to individualise treatment.

Incidence and Survival Patterns of Rare Anal Canal Neoplasms Using the Surveillance Epidemiology and End Results Registry

Small cell, neuroendocrine tumors, and melanoma of the anus are rare. Limited data exist on the incidence and management for these rare tumors. A large, prospective, population-based database was used to determine incidence and survival patterns of rare anal neoplasms. The Surveillance, Epidemiology and End Results registry was queried to identify patients diagnosed with anal canal neoplasms. Incidence and survival patterns were evaluated with respect to age, sex, race, histology, stage, and therapy. We identified 7078 cases of anal canal neoplasms: melanoma (n = 149), neuroendocrine (n = 61), and small cell neuroendocrine (n = 26). Squamous cell carcinoma (SCC) (n = 6842) served as the comparison group. Anal melanoma (AM) demonstrated the lowest survival rate at 2.5 per cent. Neuroendocrine tumors (NETs) demonstrated similar survival as SCC (10-year survival for regional disease of 25 and 22.3%, respectively). Ten-year survival of small cell NETs resembled AM (5.3 vs 2.5%). Age 60 years or older, sex, black race, stage, and surgery were independent predictors of survival. This study presents the largest patient series of rare anal neoplasms. NETs of the anal canal demonstrate similar survival patterns to SCC, whereas small cell NETs more closely resemble AM. Accurate histologic diagnosis is vital to determine treatment and surgical management because survival patterns can differ among rare anal neoplasms.

Inguinal Lymph Node Dissection Does Not Improve Overall Survival in Anal Cancer Nodal Disease

BACKGROUND

Anal SCC is a rare disease mainly treated with chemoradiation. Abdominoperineal resection (APR), once the mainstay of treatment for anal cancer, now serves a role as salvage therapy for persistent or recurrent disease after chemoradiation. In addition, clinically positive nodes are currently treated by extending the radiation field to the groin. The role of inguinal lymph node dissection in recurrent or persistent anal SCC is unclear. The aim of the study is to determine the role of inguinal lymph node dissection in the management of inguinal lymph node metastasis for anal squamous cell carcinoma (SCC).

METHODS

Retrospective analysis of patients with anal SCC in the National Cancer Database with positive inguinal nodes undergoing salvage APR between 2004 and 2014 was performed. A comparison of overall survival between patients who underwent APR with lymph node dissection versus APR only was analyzed using Kaplan-Meier plot.

RESULTS

A total of 3424 patients underwent salvage APR, with 274 (8%) having clinically positive nodes. Within the subgroup that had clinically positive nodes, 195 (71%) underwent APR, whereas 79 (29%) underwent both APR and node dissection. Kaplan-Meier analysis demonstrates no difference in overall survival in the two groups (P = 0.99). Five-year survival for both groups was similar (36% versus 42%; P = 0.987). No significant difference was found when adjusted for age, gender, and Tumor Node Metastasis staging.

CONCLUSIONS

Inguinal lymph node dissection does not appear to improve overall survival in patients with advanced-stage anal cancer requiring salvage APR. Proper patient selection for node dissection is essential to spare patients from additional morbid procedures.

Long-term results achieved by guideline-based stage-dependent management of anal cancer in a non-HIV population

PURPOSE

Therapy of anal cancer follows national and international guidelines that are mainly derived from randomized trials. This study aimed to analyze long-term results of stage-dependent treatment of anal cancer in a non-selected patient cohort.

PATIENTS AND METHOD

All consecutive patients treated for anal cancer between 2000 and 2015 were retrieved from a prospective database. Risk-dependent screening for human immunodeficiency virus showed no infection. Main outcome measure was overall survival with respect to tumor site and treatment. Secondary endpoints were cause-specific survival, stoma free survival, and the rate of salvage operations.

RESULTS

In total, 106 patients were treated for anal cancer. Of those, 69 (65.1%) suffered from anal canal cancer and 37 (34.9%) from anal margin cancer. Three patients with synchronous distant metastases were excluded from analysis. The majority of patients (n = 79, 76.7%) were treated by chemoradiotherapy in curative intention. Twenty-two patients underwent local surgery. Five-year overall survival was 73.1% and cause-specific survival at 5 years was 87.4%. Overall, 14 patients (13.6%) needed salvage surgery. Their 5-year cause-specific survival was 57.7%. A permanent ostomy was avoided in 77.7%.

CONCLUSIONS

Treatment of anal cancer results in low rates of salvage surgery and permanent ostomies, when therapy was determined by a multidisciplinary team following national and international guidelines.

Premalignant and Malignant Perianal Lesions

Anal cancer is a heterogeneous and rare disease process that accounts for ∼1.5% of all gastrointestinal tract malignancies. The perianal skin plays host to a variety of different premalignant and malignant lesions, all with variable histology, treatment options, and prognosis. Anal cancers in general are notorious for having a delayed or missed diagnosis leading to treatment delays and may have an impact on survival. This delay is in part due to the nonspecific symptomatology and also improper physical examination of the sensitive and anatomically complex perianal region and anal canal. This article examines the various types of perianal cancers and their precursor lesions and will explore treatment options as well as outcomes and prognosis.

Perianal Goblet Cell Carcinoid With Pagetoid Spread

We present a case of perianal goblet cell carcinoid with pagetoid spread. Goblet cell carcinoid, also known as adenocarcinoid tumor, predominantly arises as a primary appendiceal tumor and contains nests of neuroendocrine and mucin-containing cells. When this tumor type is seen in other sites it usually represents a metastasis. We present the case of an 81-year-old woman with a perianal mass. Histologic and immunohistochemical examination following surgical excision showed a goblet cell carcinoid demonstrating pagetoid spread along the perianal squamous mucosa. There was no evidence of a primary appendiceal tumor by history or imaging studies. To our knowledge, this is the first report of a goblet cell carcinoid presenting in this manner. The patient died due to complications of metastatic disease 26 months after initial diagnosis.

Human papilloma virus and squamous cell carcinoma of the anus

The incidence of anal cancer is increasing. In the UK, the incidence is estimated at approximately 1.5 per 100,000. Most of this increase is attributed to certain at-risk populations. Persons who are human immunodeficiency virus (HIV)-positive and men who have sex with men (MSM), Organ transplant recipients, women with a history of cervical cancer, human papilloma virus (HPV), or cervical intraepithelial neoplasia (CIN) are known to have a greater risk for anal cancer. This paper will focus on HPV as a risk factor for anal intraepithelial neoplasia (AIN) and discusses the etiology, anatomy, pathogenesis, management of squamous cell carcinoma (SCC) of the anus.

Anal Cancer debuting as Cancer of Unknown Primary

Anal cancer usually presents with a visible or palpable tumour. In this case we describe a 54-year old man diagnosed with Cancer of Unknown Primary (CUP) with a single inguinal node as the only finding. Thorough examination failed to identify any primary tumour. The patient was treated with lymph node dissection and not until nearly two years after initial diagnosis, was the primary tumour found, and the patient was diagnosed with anal cancer. The patient was treated with chemoradiotherapy and 45 months after initial diagnosis there is still no sign of relapse. This case illustrates, that anal cancer can metastasise before the primary tumour is detectable. Furthermore, it demonstrates the necessity of thorough clinical follow-up after treatment of CUP since the primary tumour was found later. Finally this is a case of a long-term survivor following treatment for metastatic inguinal lymph nodes from an initially unknown primary cancer.

Neoplasms of anal canal and perianal skin

Tumors of the anus and perianal skin are rare. Their presentation can vary and often mimics common benign anal pathology, thereby delaying diagnosis and appropriate and timely treatment. The anatomy of this region is complex because it represents the progressive transition from the digestive system to the skin with many different co-existing types of cells and tissues. Squamous cell carcinoma of the anal canal is the most frequent tumor found in the anal and perianal region. Less-frequent lesions include Bowen's and Paget's disease, basal cell carcinoma, melanoma, and adenocarcinoma. This article aims to review the clinical presentation, diagnostic evaluation, and treatment options for neoplasms of the anal canal and perianal skin.

Racial disparity in death from colorectal cancer: does vitamin D deficiency contribute?

BACKGROUND

The reasons blacks have higher mortality rates from colorectal cancer (CRC) than non-Hispanic whites are not fully understood. Blacks have higher rates of vitamin D deficiency than non-Hispanic whites, and vitamin D deficiency has been associated with CRC. The authors of this report investigated the association of vitamin D deficiency with excess risk for CRC mortality for blacks in the Third National Health and Nutrition Examination Survey (NHANES III) that was conducted from 1988 to 1994.

METHODS

The association between serum 25(OH)D levels and CRC mortality and its contribution to elevated risk among blacks were studied using baseline data from NHANES III and CRC mortality data through 2006 from the National Death Index. By using survival models, the adjusted risk of death from CRC for African Americans was examined with and without adjusting for vitamin D deficiency, which was defined as an 25(OH)D level <20 ng/dL.

RESULTS

Black race (hazard ratio [HR], 2.03; 95% confidence interval [95% CI], 1.04-3.95), age (HR, 1.12; 95% CI, 1.09-1.15), not having health insurance (HR, 2.45; 95% CI, 1.12-5.36), and a history of CRC (HR, 7.22; 95% CI, 2.12-24.6) predicted CRC mortality. When added to the model, vitamin D deficiency was associated significantly with CRC mortality (HR, 2.11; 95% CI, 1.11-4.00), and the effect of race was decreased (HR, 1.60; 95% CI, 0.87-2.93); the 40% attenuation was statistically significant (F(1) (,49) = 4.85; P = .03). Similar results were observed when participants who had a history of CRC were excluded from the analysis.

CONCLUSIONS

The current findings were consistent with the hypothesis that vitamin D deficiency contributes to excess African-American mortality from CRC. Cancer 2011.