P1877 - A Rare Case of Metachronous Squamous Cell Carcinoma of the Esophagus After Resolution of Prior Adenocarcinoma

Award: Presidential Poster Award

Sobaan Taj, MD¹, Azhar Hussain, MD², Harshavardhan Sanekommu, MD³, Jayasree Ravilla, MD⁴, Fnu Vikash, MD⁵, Henna Pervaiz, MD⁶, Saira Chaughtai, MD^3
1Hackensack Meridian Jersey Shore University Medical Center, Neptune, NJ; ²SUNY Upstate Medical University, New York, Syracuse, NY; ³Jersey Shore University Medical Center, Woodbridge, NJ; ⁴Monmouth Medical Center/RWJBH, Long Branch, NJ; ⁵Jacobi Medical Center, Albert Einstein College of Medicine, Bronx, NY; ⁶SUNY Downstate Medical Center, Brooklyn, NJ

Introduction: Esophageal cancer, primarily manifesting as adenocarcinoma and squamous cell carcinoma, ranks the sixth leading cause of cancer-related deaths globally. The term "metachronous" refers to multiple independent primary malignancies, with subsequent malignancies arising more than six months after diagnosing the first. It is scarce to see metachronous esophageal cancers with different histologic subtypes in a single patient. We present a unique, unreported case of this sequence.

Case Description/Methods: A 67-year-old male smoker, previously treated for T2N0Mx esophageal adenocarcinoma, presented with worsening dysphagia and one episode of hematemesis. Three years prior, he had been diagnosed with biopsy-proven esophageal adenocarcinoma (Figure 1A & 1B). Post chemoradiation and a year of remission, he presented again with recurring dysphagia symptoms. A computed tomography angiography (CTA) showed no active gastrointestinal bleeding but mild diffuse esophageal dilation and mid-distal esophageal wall thickening. An EGD revealed a medium-sized, fungating, non-bleeding, partially obstructing, and ulcerating mass in the lower third of the esophagus, where the previous adenocarcinoma was located (Figure 2). Biopsies confirmed moderately differentiated squamous cell carcinoma (Figures 3A & 3B), leading to the patient undergoing open gastrostomy tube placement and scheduling outpatient chemotherapy.

Discussion: The literature characterizes multiple primary malignant tumors (MPMT) as several malignancies originating from distinct tissues with unique morphologies. Malignancies appearing within six months are "synchronous," while those after six months are "metachronous." Esophageal adenocarcinoma (EAC) and squamous cell carcinoma (SCC) share risk factors like age, smoking, and male sex. This could account for the metachronous occurrence of SCC following EAC under "field cancerization." Studies suggest that thermal injury from radio-frequency ablation, used to eradicate adenocarcinoma, could predispose the tissue to squamous cell proliferation, considering the common progenitors of the columnar and squamous epithelium. Another explanation is radiation therapy-induced damage for previous cancers, a leading risk factor for SCC. MPMTs, with an incidence rate of 0.52% to 11.7%, underscore the importance of screening for recurrence and second primary malignancies, urging clinicians and endoscopists to maintain vigilance.



Disclosures:


Sobaan Taj, MD¹, Azhar Hussain, MD², Harshavardhan Sanekommu, MD³, Jayasree Ravilla, MD⁴, Fnu Vikash, MD⁵, Henna Pervaiz, MD⁶, Saira Chaughtai, MD³. P1877 - A Rare Case of Metachronous Squamous Cell Carcinoma of the Esophagus After Resolution of Prior Adenocarcinoma, ACG 2023 Annual Scientific Meeting Abstracts. Vancouver, BC, Canada: American College of Gastroenterology.