Special subtypes can develop identical histopatho-logical pictures to those of ductal cancers of the breast: comedo-type structures, cribriform types, and papillary structures. Like ductal breast cancers, these types can also overexpress c-erb B2, and with it pl85 protein.
In addition to these cancer types, anaplastic, partly small-cell, cancers can occur (Figs. 18, 19).
Knowledge of the aspiration cytology of benign and malignant tumors in the head and neck region is frequently helpful in making decisions on performing surgery, extending of operative procedures and operation planning, essentially also with re
spect to SLN labeling and locoregional tumor clearance.
Both cancer subtypes developed in primarily benign lesions and malignant tumors in the salivary glands metastasize predominantly by the lympho-genous route, and in later stages, in some cases also hematogenously, mostly into the lungs. This holds true for both highly differentiated and less well-differentiated salivary cancer types.
Pre- or intraparotid lymph node involvement or check up of these nodes, for instance in cutaneous malignant melanomas of the face, is rare.
In diagnosis of parotid gland tumors (CT, MRI, FDG-PET etc.), 99mTc-nanocolloid labeling and/or blue dye labeling could be used for SLN detection.
It is astonishing that no activity has yet been encouraged in this direction: I think this is due not so much to fear of inducing the development of a salivary gland fistula as to lack of knowledge about the newly introduced SLN concept.
In summary, a sentinel node concept for primary salivary gland cancers, especially for the parotid gland cancers, does not exist.
Up to now, no SLN studies have been carried out and no published results are available. It might be that the imaging systems are sufficient enough to detect pre- and retroparotidean nodes. But the possibility that more precise locoregional cancer clearance can be achieved when the labeling procedures are used also cannot be excluded.
Usage of the sentinel node concept in the treatment of face tumors with pre- or intraparotidean SLNs does not seem to involve any great problems (see Table 3).
In comparative studies of 99mTc Re (Rhenium) and 99mTc HAS-D (human serum albumin diethy-lene-triamine pentaacetic acid), Sato et al. (2000) demonstrated that 99mTc-Re was superior to 99mTc HAS-D as an agent.
It might be that new compounds with higher efficiency can improve the SLN detection rate and help to overcome the problems encountered when primaries and sentinel nodes are too close to each other.
Was this article helpful?