Small-cell malignant lesions of the thyroid gland

Small cell carcinoma of the head and neck: a review

Small cell carcinoma (SCC) has become recognized as a distinct, though relatively infrequent, clinical pathology that occurs in multiple sites throughout the head and neck. Excluding cases that are considered to arise from skin, SCC in the head and neck has been found to develop in nearly all structures associated with the upper aerodigestive tract. Among the head and neck sites, the frequency of SCC is greatest in the larynx, with salivary glands and the sinonasal region comprising the other principle areas of origin. Controversy exist as to whether SCC can develop as a distinct entity in the thyroid, with most tumors that previously would have been considered as SCC now found to be lymphomas or variant forms of other types of thyroid malignancy. While there seems to be some differences among tumors arising from the various subsites, in general all SCC that originate in the head and neck have a tendency for aggressive local invasion and a strong propensity for both regional and distant metastasis. Treatment may include surgical resection, radiotherapy, chemotherapy, or some combination of these modalities. Due to the infrequency of these tumors, it is very unlikely that any large, controlled study will ever be done. For this reason, recommendations for treatment of SCC arising in the head and neck are based primarily on retrospective data from various small case series and on comparative data for treatment of SCC of bronchogenic and other extrapulmonary origin. Although patients with truly limited local disease may enjoy some prolonged survival, most patients with this tumor do poorly despite all current attempts at treatment.

Malignant lymphoma of the thyroid

Two cases of malignant lymphoma are reported and the clinical features of a further 6 cases collected over a 10-year period are presented. The literature is reviewed and the treatment, prognosis and relationship to Hashimoto's disease are discussed. It is suggested that lymph node biopsy at the time of operation is important in confirming the diagnosis and that the prognosis may be more hopeful than has previously been suggested.

MALIGNANT LYMPHOMA OF THE THYROID

Nine cases of malignant lymphoma of the thyroid are described; the clinical features and histological patterns are recorded and the latter related to results of serological tests for thyroid antibodies. The value of such tests in clinical assessment is discussed. The distribution of metastases and their predilection for the gastrointestinal tract is noted.

Primary lymphoma of the thyroid: clinical features, prognostic factors, and results of treatment

This study analyzes the results of 46 cases of biopsy-proven primary lymphoma of the thyroid, localized at diagnosis and treated at the Royal Marsden Hospital between 1948-1980. In all cases, disease was limited to the thyroid and cervical lymph nodes. There were 43 females and 3 males, with a mean age of 64.4 years (median 66 years; range 17-86). A short history (less than 3 months) of a neck mass and local compressive symptoms was the typical presentation. The majority of patients (91%) had adverse histologies, with diffuse histiocytic lymphomas being most common (78%). The overall crude 5-year survival rate was 40%, with 30% of patients surviving beyond 10 years. Disease-free and overall survival were virtually identical, indicating the ineffectiveness of salvage therapy. The important prognostic factors were: size of tumor, fixation, extra-capsular extension, and retrosternal involvement. Survival was not correlated with age, sex, histology, thyroid status, or stage of disease, as defined by the Ann Arbor classification. Patients who had total macroscopic removal of tumor had the highest rate of local control and long survival (p less than 0.005). No significant difference was seen between lobectomy, subtotal or total thyroidectomy, but 7 of 9 long-term survivors (58-129 months) have had total thyroidectomy. A radiotherapy dose to the tumor, of at least 40 Gy, was required to produce consistent local control in patients with unresected disease. The majority of patients who died had generalized disease. Only 52% of these patients were free of local recurrence. In view of the frequency of occult disseminated disease, adjuvant chemotherapy is one recommendation for patients with poor prognostic factors. For optimal local control, complete surgical eradication is recommended followed by high-dose local radiotherapy. The use of aggressive cytoreductive chemotherapy prior to radiotherapy is a possible alternative option which needs to be explored.

The value of immunocytochemical methods in the differential diagnosis of anaplastic thyroid tumours

The practical usefulness of a panel of monoclonal antibodies recognising epithelial and lymphoid antigens has been evaluated on a series of 10 routinely processed thyroid tumours of uncertain origin. All 6 small cell tumours were shown to be of lymphoid origin whereas of the 4 large cell tumours two were lymphomas and two carcinomas. Two of the tumours, one large cell and one small cell, were undiagnosable due to technical reasons (crush artefact or small size of biopsy) and emphasized the value of immunohistology in this context. Clinical follow-up of all 10 cases indicated that these distinctions are of both prognostic and therapeutic value. It is concluded that immunocytochemistry using a carefully selected panel of monoclonal antibodies is a valuable and convenient means of making an objective distinction between anaplastic thyroid tumours of epithelial or lymphoid origin.

Anaplastic small cell neoplasms of the thyroid: an immunoperoxidase study

The cell origins of ten anaplastic small cell neoplasms of the thyroid gland were investigated using the immunoperoxidase technique. Sections of the neoplasms were examined for immunostaining for the tissue markers of B lymphocytes, thyroid follicular cells, and C cells by incubation with antisera to the lambda and kappa light chains, human thyroxine and human calcitonin, respectively. Six neoplasms were identified as malignant lymphomas, and two were identified as anaplastic small cell follicular carcinomas. The cell origins of the remaining two neoplasms could not be determined. The prognosis for patients with malignant lymphoma was favorable compared with the prognoses for patients in the other two groups. The prognosis for patients with anaplastic small cell follicular carcinomas was better than for those with small cell malignancies of undetermined cell origins. These findings suggest an important role for the immunoperoxidase technique in the precise classification of anaplastic small cell neoplasms of the thyroid.

Malignant lymphoma of the thyroid gland: a clinicopathologic study

This study reviews 21 cases of thyroid lymphoma diagnosed between 1969 and 1980. The thyroid gland was the primary site in all but two cases. The 20 patients with non-Hodgkin lymphoma had a mean age of 66 years, 75% were women, and all were Caucasian. A rapidly growing thyroid mass with hoarseness, dysphagia, and difficulty in breathing was the initial finding. Most patients had diffuse histiocytic lymphomas. Associated Hashimoto thyroiditis was found histologically in 57% of the cases. Using the immunoperoxidase stain method on tissue sections, intracytoplasmic monoclonal immunoglobulin was demonstrated in 5 of 15 cases. All but two patients received radiation therapy, and 13 received chemotherapy. The median survival was 8 months; 20% died of unrelated causes and 32% are alive (average duration: 27 months). Dissemination, after local control by radiation therapy, was the leading cause of death. The prognosis was better in men, in patients under the age of 65 years, and in those patients who, on biopsy, did not have involvement of the extrathyroid soft tissue or regional lymph nodes.

The natural history of malignant thyroid lymphomas

Twelve patients with malignant thyroid lymphomas seen over a 12-year period were reviewed. Two of these patients developed intra-abdominal lymphoma and a third, adult coeliac disease. Treatment by radiotherapy and thyroxine was effective, with thyroid excision mainly reserved for obstructing lesions. Prognosis was not affected by local metastases. A plea is made for open thyroid biopsy and accurate clinical staging of patients with this disease.

Anaplastic carcinoma of the thyroid: a review of 84 cases of spindle and giant cell carcinoma of the thyroid

Eighty-four cases of spindle and giant cell carcinoma of the thyroid were reviewed. This is a swiftly growing, and rapidly fatal neoplasm that generally develops in the elderly. Treatment of this disease was generally unsuccessful with a 7.1% five-year survival rate and a mean survival period of 6.2 months from the time of tissue diagnosis. In the majority of cases, areas of well-differentiated thyroid carcinoma could be identified, supporting the concept that spindle and giant cell carcinoma results from the transformation of preexisting well-differentiated thyroid carcinoma. Because of the aggressive biologic activity of this neoplasm, we treat all cases as disseminated disease at the time of presentation. Our best therapeutic results have been obtained with a combination of surgery, irradiation, and chemotherapy; however, these results still leave much to be desired. Patients with only small foci of spindle and giant cell carcinoma, at the time of diagnosis, may have a better chance of prolonged survival.

Small cell malignant tumors of the thyroid. A light and electron microscopic study

Three small cell malignant tumors involving the thyroid gland were examined by light and electron microscopy. In each, numerous similarities were presented on light microscopic analysis rendering interpretation difficult. In the first patient the small cells were identified on electron microscopy as moderately well differentiated lymphocytes. This tumor occurred in an elderly woman as a locally invasive thyroid tumor, subsequently involving distant sites, including the liver, spleen, lymph nodes, and soft tissue. The tumor repeatedly regressed following radiotherapy. The patients eventually died with disseminated lymphocytic lymphoma. In the second patient the thyroid tumor, also locally invasive, was composed principally of neoplastic epithelial cells when studied on electron microscopy. This patient responded poorly to radiation and died within a year after diagnosis. The third patient presented with an enlarging thyroid mass, which ultrastructurally was found to be composed principally of well differentiated lymphocytes. Subsequent clinical evaluation established a diagnosis of chronic lymphocytic leukemia. Small cell malignant tumors of the thyroid represent a difficult diagnosis problem for surgical pathologists. Ultrastructural study, we believe, is a useful adjunct in the differentiation of these tumors.