Esophageal adenocarcinoma (EAC) is a poor prognostic disease, the 5-year survival rate for people with esophageal cancer is 20%. According to the current literature, the rate of HER2 positivity in EAC varies, ranging from 15 to 29%. Currently there is no data about the incidence rates of HER2-positive proximal EAC.
76-year old man presented in 2015 to our hospital, ECOG 1, with loss of weight and dysphagia. His Medical history was significant for primary hypertension and benign prostate hyperplasia. He was an active Smoker (30 pack-years) and Alcoholic. Denied family history for neoplasm.
Initial staging with upper gastroinstestinal (UGI) endoscopy shows a circumferential, friable, ulcerated and infiltrative lesion that is 19 cm from the ADS and extends up to 26 cm. CT showed thickening of the middle and proximal esophagus with regional lymph node enlargement. Presence of distant metastases was not detected.
Histopathological findings showed Proximal esophagus moderately differentiated, ulcerated and invasive adenocarcinoma. Immunohistochemical (IHC) analysis showed HER2 3+, CK7 positive, CK20 positive, CDX2 positive and GATA-3 negative.
At the time given the lack of accurate data on anti HER2 therapy for EAC, the sistemic chemotherapy (CT) chosen was carboplatin plus Paclitaxel. After 5 months he presented local progression. We chose Folfox as next line CT and after that local Radiotherapy. Follow up with CT Scans and UGI endoscopy.
After 4 years of stable disease patient presented to our hospital with odinophagy, increased esophageal lesion and loss of weight. we proposed modified FOLFOX (mFOLFOX) with dose reduction 5-FU and oxaliplatin. After 2 cycles of mFOLFOX the patient is currently presenting good clinical response.
Overexpression and amplification of HER2 is generally correlated with worse prognosis in solid malignancies. The impact of HER2 overexpression on EAC are conflicting, since studies do not differ EAC from gastric cancer and esophageal.
Recent studies shows negative results with adding Trastuzumab to standard of care. Despite that HER 2 remains an important target. Precision oncology is currently working on trials to access different ways to access these biomarkers.