Sustained response of HER2-positive metastatic salivary adenocarcinoma, not otherwise specified, treated with trastuzumab.
OBJECTIVE
Adenocarcinoma-not otherwise specified (AD-NOS) is an aggressive salivary gland carcinoma subtype with poor prognosis. Her2/neu-targeted therapy may be beneficial in cases of overexpression (20% of AD-NOS). Here, a case of metastatic AD-NOS of the submandibular gland showing sustained complete response to trastuzumab is reported, and the existing literature is reviewed.


RESULTS
A 68-year-old male with poorly differentiated AD-NOS of the submandibular gland with multiple metastases (T3 N2 bM1) underwent radical surgery and adjuvant radiation. The primary lesion demonstrated Her2/neu overexpression, and treatment with trastuzumab was initiated. The patient remains alive without evidence of disease at 36-months after treatment (three cycles of trastuzumab). Literature review of all published trastuzumab-based therapy studies (1990-2015) for salivary gland carcinoma is included.


CONCLUSIONS
Definitive clinical trials of trastuzumab-based interventions are challenging to undertake in rare tumors. This report adds to increasing evidence for trastuzumab-based therapy in salivary carcinomas, where sustained partial response at 36-months is achievable.
Division of Oncology & Reconstructive Surgery, Department of Oral & Maxillofacial Surgery, Greenebaum Cancer Center, University of Maryland, Baltimore, MD, USA.
Naseem
N
Ghazali
Department of Pathology, University of Maryland Medical Center, Baltimore, MD, USA.
Lynette
L
Parker
Chesapeake Potomac Regional Cancer Center, Waldorf, MD, USA.
Kathleen
K
Settle
Division of Oncology & Reconstructive Surgery, Department of Oral & Maxillofacial Surgery, Greenebaum Cancer Center, University of Maryland, Baltimore, MD, USA. Electronic address: jlubek@umaryland.edu.
Joshua E
JE
Lubek
D000230:Adenocarcinoma / Q000188:drug therapy* / Q000556:secondary* / Q000628:therapy; D000368:Aged; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D003131:Combined Modality Therapy; D003937:Diagnosis, Differential; D003952:Diagnostic Imaging; D006801:Humans; D008113:Liver Neoplasms / Q000473:pathology; D008297:Male; D037981:Neck Dissection; D009367:Neoplasm Staging; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases; D012468:Salivary Gland Neoplasms / Q000188:drug therapy* / Q000556:secondary* / Q000628:therapy; D013249:Sternum / Q000473:pathology; D000068878:Trastuzumab / Q000627:therapeutic use*
D000970:Antineoplastic Agents; D018719:Erb-b2 Receptor Tyrosine Kinases; D000068878:Trastuzumab; C508053:ERBB2 protein, human