Craniofacial Block-Resections in Malignant Tumors of a Skull Base

A.M. Zaitsev, V.A. Cherekaev, I.V. Reshetov, A.I. Belov

(Burdenko Research Institute of Neurosurgery, Moscow)

Treatment of cases with malignant craniofacial neoplasms is strongly dependent on improvement of diagnosis with the purpose of revealing early stages of the disease, development of effective methods of treatment, including pre- and postoperative radio- and chemotherapy, as well as removal of a pathologic mass within the limits of intact tissues. According to medical literature, a correct choice of treatment tactics allows to achieve a relapse-free period of five years in 40-60% of cases.

Development of effective methods of reconstructive and plastic surgery became the basis for performing block-resections in patients with malignant tumors of a skull base, when neoplasm was removed as a single block with adjacent intact tissues (dura, muscles, skull base and facial skeleton bones, mucosa, orbit tissues, skin).

Craniofacial block-resection is one of the stages, included into complex treatment of cases with malignant skull base tumors. Malignant craniofacial neoplasms tend to local spread and are a rare cause of both regional and remote metastases. This fact is the grounds for a conception of possible curability of malignant craniofacial tumors by their removal as a single block with adjacent intact tissues. Preparing a patient for block-resection, one should carry out a profound examination for excluding metastases and determining exact localization and spread, as it permits to plan a volume of resection and to choose a method of plasty.

There are two main methods of block-resection:

I. Anterior craniofacial block-resection.

The block includes a nasopharynx, ethmoidal and sphenoid sinuses, an olfactory fossa. Depending on a spread of a pathologic process, this block can become more extensive and involve an orbit, maxillary sinus and pterygopalatine fossa. Dura defects are closed by free fragments of fatty tissue with an advanced periosteal graft, placed above them. Extensive defects of bones and soft tissues are closed by a musculocutaneous graft on a vascular pedicle. Its cutaneous surface is used for forming a palatine area and a base for an eye prosthesis. A musculocutaneous graft is raised from the broadest muscle of the back, musculus serratus anterior, musculus pectoralis major, musculus rectus abdominis. In case of extensive damage of dura, it is more expedient to close these defects by a flap of the greater omentum, having a vascular pedicle.

II. Lateral craniofacial block-resection.

The block includes structures, forming an infratemporal fossa, articular and coronoid processes of the mandible, external segments of the temporal bone pyramid, a maxillary sinus, orbit and base of the anterior cranial fossa, which, in its turn, forms an orbit roof.

A lumbar drain is inserted before craniofacial block-resection. It is removed on the 6th-8th day after operation.

At present we have introduced a method of craniofacial block-resections into clinical practice. Operations are performed together with oncologists and plastic surgeons of the Moscow Research Oncologic Institute named after P.A.Gertsen. A tumor is removed as a block together with adjacent intact tissues. It is followed by plasty of defects with a musculocutaneous graft or a flap of the greater omentum and subsequent cosmetic correction.

During 1996-2002 we performed block-resection with primary plasty of defects in 23 cases. Distribution of tumors according to their histological structure was as follows: epithelial tumors 90%; sarcomas, malignant chondromas, esthesioneuroepitheliomas 10%.

A follow-up period was 5 years. A survival rate was 61%; 9 cases (39%) died during this period. A mean age was 40.1 years.