Framework invasion by laryngeal carcinomas

Functional Anatomy and Oncologic Barriers of the Larynx

Laryngeal barriers to tumor spread are a product of laryngeal development, anatomic barriers, and enzymatic activity. Supraglottic and glottic/subglottic development is distinct and partially explains the metastatic behavior of laryngeal carcinoma. Dense connective tissues and elastic fibers provide anatomic barriers within the larynx. Laryngeal cartilage contains dense cartilage, enzyme inhibitors, and an intact perichondrium making it relatively resistant to tumor invasion; however, focal areas of vulnerability are created by ossified cartilage and natural interruptions in the perichondrium. Local inflammation and the enzymatic interplay between tumor and host are important factors in the spread of laryngeal tumor.

Head and neck cancer pain: systematic review of prevalence and associated factors

OBJECTIVES

Pain is a major symptom in patients with cancer; however information on head and neck cancer related pain is limited. The aim of this review was to investigate the prevalence of pain and associated factors among patients with HNC.

MATERIAL AND METHODS

The systematic review used search of MEDLINE, EMBASE and CINAHL databases to December 2011. Cancers of the oral mucosa, oropharynx, hypopharynx and larynx were included in this review with pain as main outcome. The review was restricted to full research reports of observational studies published in English. A checklist was used to assess the quality of selected studies.

RESULTS

There were 82 studies included in the review and most of them (84%) were conducted in the past ten years. Studies were relatively small, with a median of 80 patients (IQR 44, 154). The quality of reporting was variable. Most studies (77%) used self-administered quality of life questionnaires, where pain was a component of the overall scale. Only 33 studies reported pain prevalence in HNC patients (combined estimate from meta-analysis before (57%, 95% CI 43% - 70%) and after (42%, 95% CI 33% - 50%) treatment. Only 49 studies (60%) considered associated factors, mostly tumour- or treatment-related.

CONCLUSIONS

The study has shown high levels of pain prevalence and some factors associated with higher levels of pain. There is a need for higher quality studies in a priority area for the care of patients with head and neck cancer.

Total laryngectomy and postoperative radiotherapy for T4 laryngeal cancer: a 14-year review

OBJECTIVE

The most appropriate treatment of locally advanced carcinoma of the larynx remains to be ascertained. Management of T4 laryngeal cancer patients with postoperative radiotherapy after total laryngectomy is generally advocated and not often debated. However, the effects of this combined treatment approach are poorly documented. We reviewed the oncologic outcome and long-term survival of individuals treated by total laryngectomy and postoperative radiotherapy (TLPR) for T4 carcinoma of the larynx.

METHODS

Twenty-eight patients with a pathologic diagnosis of T4 laryngeal cancer treated by TLPR during a 14-year period were studied retrospectively. Median follow-up from treatment until the end of observation was 36 months (range 6 to 123 months).

RESULTS

The overall actuarial and disease-free survival rates at 7 years were 43% and 30%, respectively. Local recurrence, regional relapse, and distant metastasis developed in 4%, 4%, and 7% of the cases, respectively. Later esophageal stricture, dental caries, or carotid artery disease in 3 patients (11%) was successfully managed. Multivariate analysis showed patient age, bilateral true vocal cord-anterior commissure involvement by laryngeal cancer (horse-shoe lesion), and any type of treatment failure to be the most predictive variables affecting prognosis.

CONCLUSION

Long-term disease control and survival is achievable by TLPR with minimal late toxicity in patients with T4 carcinoma of the larynx.

Patterns of failure after total laryngectomy for glottic carcinoma

The 136 patients who underwent total laryngectomy as the primary treatment for squamous cell carcinoma of the glottis at the Mayo Clinic in 1970 through 1981 were followed by retrospective record review for at least 4 years or until death, local recurrence, neck recurrence, or delayed neck metastasis. Cancer recurred or progressed in a previously untreated area in 35 patients; for the 29 affected above the clavicles, the median time to manifestation was 9.9 months. A Cox model with four risk factors (P less than 0.05) was found to predict failure above the clavicles: lymph node metastasis in the laryngectomy specimen (Delphian, pretracheal, tracheoesophageal, parathyroid), primary tumor more than 1.5 cm in greatest diameter, subglottic extension, and lymph node metastasis in the neck dissection specimen. A simple risk score computed from the Cox model shows that the more factors present, the higher the risk of disease progression or recurrence.

Microlaryngology: an update on its modern use in laryngology--malignant early and advanced glottic carcinoma

The modern use of microlaryngology is improving the diagnosis and treatment of early and advanced glottic laryngeal lesions. Microlaryngology is a microscopic laryngoscopic technique that is used to carry out laryngeal tumor evaluation and biopsy. For early, small, and advanced laryngeal glottic lesions, a microscope is used to view the larynx through a laryngoscope that is placed transorally. This is a precise method of microsurgery to biopsy and stage early and advanced malignant tumors of the glottic area of the larynx. Recent advances using microscopic visualization, microsurgical instruments, and a CO2 laser as a tool to control bleeding and to debulk the tumors of patients with advanced lesions enable the operating surgeon to visualize accurately the involvement by tumor of the overlying mucosa or the underlying muscles and cartilages in this area and sometimes to restore the airway. Precise knowledge regarding the microscopic locational extent of these tumors is important in developing appropriate options for treatment of early and advanced malignant neoplasms of the glottic area of the larynx in order to cure the disease and save the voice of the patient.

Framework invasion by laryngeal carcinoma

Invasion of the laryngeal framework by cancer implies a tumor that has spread beyond the bounds of the organ of origin, which may affect the outcome of the disease. Framework invasion almost invariably takes place in ossified or calcified cartilage, and the reason for this has never before been adequately explained. The finding of increased density on some computerized tomography scans where the tumor was invading the framework stimulated this study of the mechanisms of this type of spread. One hundred fifty-eight consecutive laryngeal specimens were examined by a serial sectioning method to elucidate this. Several laryngeal specimens were examined for alkaline phosphatase in the tissues, and two specimens were examined for collagenase. A method of tetracycline labeling was used to measure the amount of osteoblastic activity in another two specimens. Framework invasion occurred mainly at the glottic level and exclusively in ossified or calcified cartilage. This type of invasion was associated with osteoblastic activity which appeared to be at least partially mediated by tumor-produced alkaline phosphatase. Osteoclastic activity took place hand-in-hand with the former process, and at this stage, tumor remained outside the perichondrium. Tetracycline labeling confirmed active bone deposition in these areas and appeared to explain the finding of increased ossification seen on computerized tomography scans where early invasion was taking place.

Biological studies of ten human squamous carcinoma cell lines: an overview

Ten cell lines established from surgical specimens of human squamous carcinomas of the tongue and larynx have been investigated with respect to their motility, ultrastructure, karyotypes, certain biochemical features, interaction with normal epithelial and stromal elements and capacity to infiltrate three-dimensional organoid systems. All the cell lines have maintained several morphological and biochemical characteristics indicating a common origin, although the extent to which each line displays this heritage is variable. The phenotypes of each of the individual cell lines are, however, notably stable. Data are provided for epithelial surface markers (including epidermal growth factor, EGF) and for the synthesis and release of prostaglandins and proteases which may be involved in invasive mechanisms. Encounters between the cell lines and organoid substrata (embryonic chick heart spheroids, human amnion, chick chorioallantoic membrane) are described: the results indicate a scale of invasiveness ranging from lack of penetration to full-thickness infiltration by cells showing various distinctive growth patterns. Correlation between in vitro and in vivo findings is discussed, and it is suggested that the biological heterogeneity of the lines may reflect inherent properties of the original carcinoma cell populations which are more distinctly expressed in vitro.

Patterns and mechanisms of localized bone invasion by tumors: studies with squamous carcinomas of the head and neck

Squamous carcinomas of the head and neck provide a useful model for analyzing patterns and mechanisms of tumor-associated bone destruction. Morphological studies show that a major part of the invasive process is mediated by local osteoclasts which erode bone in front of the advancing tumor. Functional studies indicate that both fresh tumors and tumor cell lines resorb calvarial bone in an in vitro test system, again by stimulating local osteoclasts. Prostaglandins of the E2 type are regularly released by the tumors, together with indomethacin-resistant, nonprostaglandin osteolysins. Control (nonneoplastic) tissues will resorb bone and release osteolytic factors, usually at lower levels of activity--such properties are thus tumor-associated rather than tumor-specific. Xenografts of squamous carcinomas resorb bone in vitro and synthesize osteolysins. They do not invade local bone in their hosts but some grafts regularly produce a systemic hypercalcemia. General implications are discussed, particularly for other human tumors which more frequently metastasize to bone. Possible pointers to the (partial) control of the destructive process are noted.

Significance and means by which laryngeal cancer invades thyroid cartilage

Involvement of the thyroid cartilage attracts a high T rating in all systems of classification for carcinoma of the larynx. Evaluation of 145 patients with laryngeal cancer treated by total laryngectomy emphasizes the difficulties of preoperatively determining cartilage invasion. The operative specimen was serially sectioned and studied to determine the means by which ossified and nonossified thyroid cartilage is invaded by carcinoma. A minimum 5-year follow-up of these cases indicates the prognostic significance of such invasion.

Patterns and mechanisms of bone invasion by squamous carcinomas of the head and neck

Patterns and mechanisms of local bone invasion by squamous carcinomas of the head and neck have been investigated. Detailed surgical pathology has shown that these tumors invade contiguous skeletal or metaplastic bone principally through an indirect process; the normal bone resorbing cells of the host (osteoclasts) are activated and erode bone in front of the advancing tumor edge. Tumor cells take over the destructive process when the osteoclast response has waned. These morphologic patterns have been reproduced in an in vitro model where calcium-45-labelled mouse calvaria, cocultured with a tumor for 3 days, are resorbed by osteoclasts. Freshly excised tumors, established tumor cell lines, and tumor xenografts release osteolysins in vitro which act as osteoclastic stimulants. They include both prostaglandins E2 and F2 alpha, and nonprostaglandin factors, and are derived from tumor cells and from the associated host stroma. Virtually all the tumors examined released osteolysins and resorbed bone in vitro independent of their site, size, degree of differentiation, and the presence or absence of clinical bone invasion.

Pain and Dysphagia in Patients with Squamous Carcinomas of the Head and Neck: The Role of Perineural Spread

Clinical and pathological features of perineural spread have been investigated in patients with squamous carcinomas at several sites in the head and neck. In 100 surgical cases, the clinical and pathological findings were congruent in 76%. Combined clinical and histological evidence of perineural invasion was recorded in 33% and the overall incidence of nerve involvement detected morphologically was 44%. Perineural infiltration was demonstrated histologically in 51% of major excisions from the buccal cavity and in 34% of resections from the oropharynx, hypopharynx and cervical oesophagus. The neurological findings were dominated by hypoaesthesia, dysaesthesia and referred pain — Mainly in the territories of cranial nerves V and IX. Multiple and/or sequential nerve involvement was occasionally seen. No correlation was established between nerve invasion and metastasis to regional lymph nodes. Long-distance infiltration of nerve trunks, and multiple involvement, are grave prognostic features.

In 17 terminal patients submitted to autopsy, 65% had combined clinical and pathological evidence of perineural spread and the overall incidence of nerve involvement detected morphologically was 88%. Sensory changes again predominated. Multiple nerve involvement was observed in 35%. An apparently new ‘dysphagia syndrome’ is described in 4 patients with oropharyngeal carcinomas in whom gross mechanical obstruction was simulated by a combination of perineural spread of tumour into the ipsilateral vagal trunk, sometimes accompanied by segmental infarction, variable invasion of the sympathetic chain, and ‘splinting’ of the pharynx by local fibrosis and tumour in the soft tissues of the neck. Short-term palliation was achieved in these patients with high-dose steroids.