Management of inguinal lymph node metastases from rectal and anal canal adenocarcinoma

The inguinal lymph nodes as regional lymph nodes in anal canal adenocarcinomas: a nationwide database analysis in Japan

PURPOSE

To establish if it is appropriate to treat the inguinal lymph node (LN) of anal canal adenocarcinoma (ACA) as the intermediate LN according to the Japanese classification.

METHODS

The characteristics of 346 ACA patients were examined from the nationwide registry. The effect of LN dissection was evaluated using the therapeutic value index (TVI). Furthermore, the prognostic classification ability of N factors and stage was evaluated using Akaike's information criterion (AIC), the concordance index (C-index), and the 5-year overall survival (OS) rate.

RESULTS

The rate of metastasis of the inguinal LN was 7.5% and the TVI was 3.05. Evaluation using AIC and the C-index showed better results when the inguinal LN was treated as the intermediate LN. The 5-year OS rate for 66 patients with perirectal or intermediate LN metastasis, 7 with inguinal LN metastasis, and 13 with inguinal and perirectal or intermediate LN metastasis were 49.2%, 68.6%, and 47.6%, respectively. When inguinal LN metastases were treated as N3, the 5-year OS rates were 66.7% for those with T1N3 and T2N3 disease, and 49.2% for those with T3N3 disease.

CONCLUSIONS

The inguinal LN of ACA was evaluated and staged as the intermediate LN to devise an appropriate treatment strategy.

A rare case of primary signet-ring adenocarcinoma of anorectal region in a young patient: Diagnostic challenges and therapeutic outcomes

Key Clinical Message

Primary signet-ring cell carcinoma of the anal canal and rectum is an extremely rare and aggressive malignancy. The present case underscores the importance of considering primary signet-ring cell carcinoma in differential diagnoses for young patients with chronic anorectal symptoms. It highlights the need for a multidisciplinary treatment approach (including surgery, chemotherapy, and radiotherapy) and comprehensive follow-up for managing this challenging condition and improving long-term patient outcomes.

Abstract

Primary signet-ring cell carcinoma of the anal canal and rectum is an exceedingly rare subtype of colorectal adenocarcinoma, often originating as an extension of rectal adenocarcinoma. This malignancy constitutes a small fraction of colorectal cancers and is scarcely reported in medical literature. We present the case of an 18-year-old male with a three-year history of progressively worsening hematochezia, anorectal pain, and defecation-associated prolapse. Initial conservative treatments failed, leading to further investigations that revealed a palpable, nodular anorectal mass. Imaging studies (including CT and MRI), and biopsy confirmed poorly differentiated adenocarcinoma with signet-ring cell morphology. The tumor exhibited extensive lymphovascular invasion and involved perirectal lymph nodes, and was staged as pT3, N2a. Immunohistochemical staining was positive for CK 7, CK 20, and SATB2, supporting the primary anorectal origin. The treatment regimen included initial diversion colostomies for symptom relief, followed by neoadjuvant chemotherapy with a modified 5-fluorouracil, leucovorin, irinotecan, and oxaliplatin (FOLFIRINOX) regimen and concurrent chemoradiation with Xeloda. The patient subsequently underwent an abdominoperineal resection (APR), which confirmed the diagnosis and achieved curative resection. Postoperative complications included transient ileus and wound infection, which were managed with supportive care. This case underscores the diagnostic and therapeutic challenges posed by primary signet-ring cell carcinoma of the anorectal region, highlighting the need for a high index of suspicion and comprehensive diagnostic workup in atypical presentations. The multimodal treatment approach, incorporating surgery, chemotherapy, and radiotherapy, was crucial in managing this locally advanced tumor. The rarity and aggressiveness of this carcinoma necessitate a tailored treatment strategy to improve patient outcomes. Long-term follow-up, including regular imaging and surveillance, is vital for monitoring disease recurrence and evaluating treatment effectiveness.

Short- and long-term outcomes of surgical treatment for inguinal lymph node metastasis in rectal and anal canal adenocarcinoma

AIM

The significance of lymphadenectomy and its indications in patients with inguinal lymph node metastasis (ILNM) of anorectal adenocarcinoma is unclear. This study aimed to clarify the surgical outcomes and prognostic factors of inguinal lymphadenectomy for ILNM.

METHOD

This study included patients who underwent surgical resection for ILNM of rectal or anal canal adenocarcinoma with pathologically positive metastases between 1997 and 2011 at 20 participating centres in the Study Group for Inguinal Lymph Node Metastasis from Colorectal Cancer organized by the Japanese Society for Cancer of the Colon and Rectum. Clinicopathological characteristics and short- and long-term postoperative outcomes were retrospectively analysed.

RESULTS

In total, 107 patients were included. The primary tumour was in the rectum in 57 patients (53.3%) and in the anal canal in 50 (46.7%). The median number of ILNMs was 2.34. Postoperative complications of Clavien-Dindo Grade III or higher were observed in five patients. The 5-year overall survival rate was 38.8%. Multivariate analysis identified undifferentiated histological type (P < 0.001), pathological venous invasion (P = 0.01) and pathological primary tumour depth T0-2 (P = 0.01) as independent prognostic factors for poor overall survival.

CONCLUSION

The 5-year overall survival after inguinal lymph node dissection was acceptable, and it warrants consideration in more patients. Further larger-scale studies are needed in order to clarify the surgical indications.

Management of Surgically Accessible Lymph Nodes Beyond Normal Resection Planes

This article discusses the management of isolated metastatic lymph nodes for colon and rectal cancer. There are traditionally significant differences in how certain regions of lymph nodes for colon and rectal cancer are managed in the East and West. This has led to the development of the lateral lymph node dissection for rectal cancer and extended lymphadenectomy techniques for colon cancer. This article will evaluate the literature on these techniques and what the surgical and oncological outcomes are at this time. In addition, colon and rectal cancers can occasionally have isolated distant lymph node metastases. These would traditionally be treated as systemic disease with chemotherapy. There is consideration though that these could be treated as similar to isolated liver or lung metastases which have been shown to be able to be treated surgically with good oncological results. The literature for these isolated distant lymph node metastases will be reviewed and treatment options available will be discussed.

Inguinal lymph node metastases from rectal adenocarcinoma: a systematic review

PURPOSE

Inguinal lymph nodes are a rare but recognised site of metastasis in rectal adenocarcinoma. No guideline or consensus exists for the management of such cases. This review aims to provide a contemporary and comprehensive analysis of the published literature to aid clinical decision-making.

METHODS

Systematic searches were performed using the PubMed, Embase, MEDLINE and Scopus and Cochrane CENTRAL Library databases from inception till December 2022. All studies reporting on the presentation, prognosis or management of patients with inguinal lymph node metastases (ILNM) were included. Pooled proportion meta-analyses were completed when possible and descriptive synthesis was utilised for the remaining outcomes. The Joanna Briggs Institute tool for case series was used to assess the risk of bias.

RESULTS

Nineteen studies were eligible for inclusion, encompassing 18 case series and one population-based study using national registry data. A total of 487 patients were included in the primary studies. The prevalence of ILNM in rectal cancer is 0.36%. ILNM are associated with very low rectal tumours with a mean distance from the anal verge of 1.1 cm (95% CI 0.92-1.27). Invasion of the dentate line was found in 76% of cases (95% CI 59-93). In patients with isolated inguinal lymph node metastases, modern chemoradiotherapy regimens in combination with surgical excision of inguinal nodes are associated with 5-year overall survival rates of 53-78%.

CONCLUSION

In specific subsets of patients with ILNM, curative-intent treatment regimens are feasible, with oncological outcomes akin to those demonstrated in locally advanced rectal cancers.

Lymph node metastasis in cancer progression: molecular mechanisms, clinical significance and therapeutic interventions

Lymph nodes (LNs) are important hubs for metastatic cell arrest and growth, immune modulation, and secondary dissemination to distant sites through a series of mechanisms, and it has been proved that lymph node metastasis (LNM) is an essential prognostic indicator in many different types of cancer. Therefore, it is important for oncologists to understand the mechanisms of tumor cells to metastasize to LNs, as well as how LNM affects the prognosis and therapy of patients with cancer in order to provide patients with accurate disease assessment and effective treatment strategies. In recent years, with the updates in both basic and clinical studies on LNM and the application of advanced medical technologies, much progress has been made in the understanding of the mechanisms of LNM and the strategies for diagnosis and treatment of LNM. In this review, current knowledge of the anatomical and physiological characteristics of LNs, as well as the molecular mechanisms of LNM, are described. The clinical significance of LNM in different anatomical sites is summarized, including the roles of LNM playing in staging, prognostic prediction, and treatment selection for patients with various types of cancers. And the novel exploration and academic disputes of strategies for recognition, diagnosis, and therapeutic interventions of metastatic LNs are also discussed.