What are the management options for a rectosigmoid mass?

Management of Rectosigmoid Masses

The management of rectosigmoid masses requires a systematic approach based on the nature of the mass, with surgical resection being the cornerstone of treatment for most cases, particularly when malignancy is suspected or confirmed. 1

Diagnostic Evaluation

• Imaging studies:

  • Contrast-enhanced abdomino-pelvic CT scan to assess the extent of the mass, potential complications, and to rule out metastatic disease 1
  • Endorectal ultrasonography for local staging of rectal tumors 1
  • Virtual colonography if complete colonoscopy is not feasible 1

• Endoscopic evaluation:

  • Flexible colonoscopy for direct visualization and biopsy of the mass 1
  • Short flexible sigmoidoscopy during endoscopic detorsion if sigmoid volvulus is suspected 1

Management Algorithm Based on Mass Type

1. Malignant Rectosigmoid Masses (Adenocarcinoma)

Early Stage (T1-T2, N0)

• T1 tumors:
  • Complete surgical resection with sphincter preservation is the standard treatment 1
  • Local transanal excision may be considered for selected T1 tumors ≤3 cm that are mobile, node-negative, and well-differentiated 1

Locally Advanced (T3-T4 and/or Node-positive)

• Neoadjuvant therapy:

  • Preoperative radiotherapy is indicated for T3 and T4 tumors 1
  • May be indicated for T2 tumors with high-risk features 1
  • Minimum recommended dose is 45 Gy using three- or four-field technique 1
  • Consider adding concurrent chemotherapy (e.g., 5-FU based regimens) 2

• Surgical approach:

  • Total mesorectal excision (TME) is strongly recommended for rectal cancer 1
  • For upper third tumors: Anterior resection or colo-anal anastomosis with sphincter preservation 1
  • For middle third tumors: Anterior resection with sphincter preservation when possible 1
  • For lower third tumors: Abdomino-perineal resection is usually required 1
  • For tumors below the peritoneal reflection: Neoadjuvant therapy appears to reduce local recurrence rates 3

• Adjuvant therapy:

  • Postoperative radiotherapy (minimum 50 Gy) if surgical margins are positive or if the tumor was understaged preoperatively 1
  • Adjuvant chemotherapy with oxaliplatin-based regimens (e.g., FOLFOX) for stage III disease 2

2. Benign Rectosigmoid Masses

Colonic Lipomas

• Small, asymptomatic lipomas (<2 cm): Observation 4
• Symptomatic or large lipomas (>2 cm): Surgical resection 4
• Endoscopically treatable lipomas: Consider unroofing, EMR, or loop-assisted resection 4
• Large lipomas (>3 cm) with ulceration: Surgical resection due to risk of complications 4

Sigmoid Volvulus with Mass Effect

• Initial management: Endoscopic detorsion using flexible endoscopy 1
• Definitive treatment: Sigmoid resection should be offered to prevent recurrence, ideally during the index admission 1
• Emergency situations: Urgent sigmoid resection if endoscopic detorsion fails or if there is non-viable or perforated colon 1

Rectal Prolapse Presenting as a Mass

• Incarcerated rectal prolapse without ischemia: Attempt gentle manual reduction under sedation 1
• Strangulated rectal prolapse: Surgical management without delay 1

Special Considerations

• Surgical approach selection:

  • The decision between isolated sigmoid colectomy versus high anterior resection should be based on vascular supply of the remnant colon 1
  • The choice between primary colorectal anastomosis, defunctioned anastomosis, or end colostomy should consider the patient's overall condition and colon viability 1

• Follow-up after treatment:

  • History and rectosigmoidoscopy every 6 months for 2 years 1
  • Complete colonoscopy with resection of polyps every 5 years 1

Pitfalls and Caveats

• Rectal cancer may present as rectal prolapse in some cases; therefore, endoscopic examination is essential in patients with rectal prolapse 1
• Completion screening colonoscopy before surgery for sigmoid volvulus has limited value due to technical difficulties with the redundant colon 1
• Local recurrence rates may be higher after anterior resection compared to abdominoperineal resection for rectal cancer 5
• In sigmoid volvulus cases, recurrence rates after conservative management alone are high (45-71%), highlighting the importance of definitive surgical management 1
• For tumors below the peritoneal reflection, failure to provide neoadjuvant therapy may result in higher local recurrence rates 3

By following this systematic approach to the management of rectosigmoid masses, clinicians can optimize outcomes while minimizing morbidity and mortality for patients with these conditions.