Intra-arterial Chemotherapy

    A Welcome New Idea for the Management of Adenocystic Carcinoma of the Lacrimal Gland 

　　ADENOCYSTIC CARCINOMA is an aggressive disease with a propensity for perineural, hematogenous, and lymphatic invasion. The prognosis is grim; approximately 70% to 80% of patients succumb to the disease within 10 years of diagnosis despite aggressive and often disfiguring treatment, and recurrences can occur 15 or 20 years after excision, making true cures extremely rare.

　　Radical orbitectomy for adenoid cystic carcinoma is advocated by many orbital specialists. This disfiguring operation involves removing the orbital contents en bloc along with various amounts of orbital bone. More recent publications have recommended eye-sparing procedures. Comparison of survival rates for radical vs eyesparing procedures has failed to demonstrate improved survival with more radical surgery. Complete surgical excision of adenocystic carcinoma of the lacrimal gland is difficult to achieve even with radical surgery. In fact, the most common site of recurrence of adenocystic carcinoma of the lacrimal gland is local. Complex regional anatomy, an infiltrative growth pattern, and perineural spread explain the apparent inability to surgically resect every malignant cell, regardless of the surgical technique used. Just a small number of cells lurking in a sensory nerve outside the margins of the radical resection can result in a late recurrence 10 or 20 years down the road.

　　Because of the well-known limitations of surgery, nearly all patients undergoing resection of adenocystic carcinoma of the lacrimal gland receive postoperative radiotherapy to the tumor bed. However, the poor rate of local control and the tendency toward late metastasis suggest that radiotherapy is unable to “sterilize” the remaining tumor cells.

　　Adenocystic carcinoma of the lacrimal gland has many similarities to malignant epithelial tumors of the parotid and salivary glands. They share common morphology, embryogenesis, and the biological potential for perineural invasion. These tumors are equally frustrating to our colleagues in head and neck surgery: the mainstay of therapy has been radical surgical excision, but an infiltrative growth pattern and perineural invasion typically limits the surgeon's ability to completely excise these lesions. Resection of tumors of the salivary gland yield tumor-free margins in only one third of cases. Unfortunately, most patients succumb to metastatic disease, even when surgery and radiation therapy has resulted in local control.

　　Chemotherapy is the treatment of choice for tumors that metastasize early and cannot be controlled locally with a combination of surgery and radiation therapy. Some patients with adenocystic carcinoma of the salivary glands respond to chemotherapy. Neoadjuvant chemotherapy with cisplatin for adenocystic carcinoma of the salivary glands combined with surgery and radiation therapy has yielded some promising preliminary results. Neoadjuvant chemotherapy combined with surgery and radiation therapy is a rational treatment choice for adenocystic carcinoma of the lacrimal gland.

　　In this issue of the ARCHIVES, Meldrum and colleagues present a novel and innovative approach using intracarotid neoadjuvant chemotherapy to treat adenocystic carcinoma of the lacrimal gland. They describe 2 patients treated with intracarotid chemotherapy prior to surgery or radiation therapy who remain disease-free 7.5 and 9.5 years after diagnosis. The patients also received radiation therapy and intravenous chemotherapy. The sample size is small and the risk of recurrence remains even after 10 years of survival. Regardless, it is impressive that these patients have attained results that are distinctly better than the norm. Their case 1 is particularly encouraging. The patient had tumor margins extending out of the orbit through the superior orbital fissure. Chemotherapy shrunk the tumor and brought the tumor margins within the orbit. Other common malignant tumors that invade the orbit, such as basal cell and squamous cell carcinoma of the skin, demonstrate shrinkage after exposure to cisplatin and doxorubicin. Some patients with nonoperative orbital basal cell and squamous cell carcinomas that invade intracranially via the superior orbital fissure may have their tumors reduced to surgically curable lesions after intracarotid chemotherapy. Ophthalmologists who grapple with adenoid cystic carcinoma and other aggressive orbital cancers should stay abreast of this promising form of adjuvant therapy.