What is the treatment for mucosal cancer?

Treatment of Mucosal Cancer

The treatment for mucosal cancer depends on the type, location, and stage, with endoscopic resection being the first-line treatment for early mucosal cancers that have not invaded beyond the mucosa. 1

Diagnosis and Staging

Before treatment selection, proper diagnosis and staging are essential:

• Endoscopic evaluation with biopsy for histological confirmation
• Endoscopic ultrasound (EUS) to assess depth of invasion
• CT scan to evaluate for distant metastases
• PET scan may be helpful to identify otherwise undetected distant metastases 1

Treatment Algorithm by Stage and Location

Early Mucosal Cancer (Tis-T1a, N0)

1. Endoscopic Resection:

   • Endoscopic Mucosal Resection (EMR) or Endoscopic Submucosal Dissection (ESD) is the treatment of choice 1
   • For esophageal adenocarcinoma: EMR is preferred for small lesions, ESD for lesions >15mm 1
   • For gastric mucosal cancer: Both EMR and ESD should be considered 1

2. Criteria for curative endoscopic resection:

   • Complete resection (negative margins)
   • No lymphovascular invasion
   • No deep submucosal invasion
   • Well or moderately differentiated histology 2, 3

3. Risk factors requiring additional treatment:

   • Tumor invasion to the muscularis mucosa (OR 4.909)
   • Presence of ulceration (OR 1.982)
   • Undifferentiated-type histology (OR 4.233) 3

Mucosal Cancer with High-Risk Features

When endoscopic resection shows high-risk features or incomplete resection:

1. Esophageal cancer:

   • Surgical resection with appropriate lymphadenectomy 1
   • For squamous cell carcinoma, chemoradiotherapy may be considered as an organ-preserving alternative 1

2. Gastric cancer:

   • Surgical resection with D2 lymphadenectomy for fit patients 1
   • Limited gastric resections only for palliation or in very elderly patients 1

Locally Advanced Mucosal Cancer (T2-T4a or N+)

1. Esophageal cancer:

   • Preoperative chemoradiation followed by surgery for adenocarcinoma 1
   • Definitive chemoradiation for squamous cell carcinoma, particularly of the proximal esophagus 1
   • Perioperative chemotherapy for type II and III esophagogastric junction adenocarcinoma 1

2. Gastric cancer:

   • Perioperative combination chemotherapy followed by surgery 1
   • D2 lymphadenectomy for fit patients with stage II-III disease 1

3. Mucosal melanoma:

   • Surgical resection with clear margins 4
   • For vulvovaginal, anorectal, or head and neck mucosal melanoma, wide local excision is preferred
   • A "wait-and-see" policy is advocated for clinically N0 patients rather than elective lymph node dissection 5

Metastatic Disease

1. Palliative options:
   • Metal stent placement for esophageal obstruction 1
   • Single-dose brachytherapy may provide better long-term relief of dysphagia than stenting 1
   • Palliative chemotherapy for selected patients 1
   • For mucosal melanoma: immunotherapy is standard management; targeted therapy for cases with BRAF or c-KIT mutations 4

Special Considerations

Buccal Mucosal Squamous Cell Carcinoma

• Particularly aggressive with high locoregional failure rates
• Consider postoperative radiotherapy even for early T1-2N0 disease 6

Mucosal Melanoma

• Poor prognosis with less than 50% survival rate at 2 years
• Lower disease stage, thinner Breslow depth, and surgical resection associated with improved overall survival
• Elective node dissection and adjuvant biochemotherapy offer no survival advantage 5, 4

Follow-up

• Regular endoscopic surveillance after endoscopic resection
• For esophageal cancer: endoscopy with biopsy 5-6 weeks after completion of preoperative therapy 1
• For patients after definitive chemoradiation: close surveillance and salvage surgery for relapse 1

Pitfalls and Caveats

1. Underestimation of invasion depth: Preoperative staging may underestimate the depth of invasion, leading to inappropriate selection of endoscopic therapy.

2. Incomplete endoscopic resection: Piecemeal resection of lesions >15mm is associated with higher recurrence rates 2.

3. Overlooking high-risk features: Even small mucosal cancers with certain histological features (undifferentiated type, lymphovascular invasion) may have lymph node metastases 3.

4. Buccal mucosal cancers: These have high recurrence rates even in early stages and may require more aggressive multimodality treatment 6.