[Surgical management of persistent diarrhea].

Area of Science:

• Endocrinology
• Oncology
• Surgical Oncology

Background:

• Medullary thyroid carcinoma (MTC) is a neuroendocrine tumor originating from thyroid parafollicular C-cells.
• Long-term surveillance is crucial for detecting recurrence, especially in patients with a history of MTC.
• Refractory diarrhea can be an unusual presenting symptom of metastatic or recurrent MTC due to calcitonin hypersecretion.

Observation:

• An 82-year-old patient with a history of MTC surgery 16 years prior presented with a cervical lesion and chronic, refractory diarrhea.
• The patient had not undergone regular tumor follow-up since the initial surgery.
• Elevated calcitonin levels and an abnormal octreotide scan suggested disease recurrence.

Findings:

• Recurrent medullary thyroid carcinoma was diagnosed based on clinical presentation, biochemical markers (high calcitonin), and imaging (octreotide scan).
• Surgical intervention (redo surgery) was performed to address the recurrent tumor.
• Post-operative resolution of the refractory diarrhea was observed, indicating the tumor was the cause of the symptoms.

Implications:

• This case underscores the potential for late recurrence of medullary thyroid carcinoma, even decades after initial treatment.
• It highlights the critical role of consistent and long-term oncologic surveillance in MTC patients to detect recurrence early.
• The successful management of diarrhea through surgical resection emphasizes the importance of identifying and treating the underlying cause of paraneoplastic syndromes associated with MTC.