Primary non-Hodgkin's lymphoma of the thyroid with bone marrow infiltration at presentation

Surgical Treatment of Primitive Thyroid Lymphoma

Aims and Background

Primitive thyroid lymphoma, although rare, is becoming more frequent. Its incidence is increasing, from 0.5% in the sixties to 1-5% of all thyroid neoplasms today. The diagnosis of such neoplasms is not always straightforward. In fact, it is often the result of pathologic findings on a gland resected for an apparently benign disease. Surgical dissection may prove more complicated than in standard cases of thyroidectomy for the possible tight adhesions existing between the gland's capsule and the surrounding structures. In cases of capsular infiltration, postoperative external local radiotherapy is indicated.

Methods

A retrospective observational analysis was performed to establish whether patients with incidental thyroid lymphomas who underwent total thyroidectomy for another pathology had major surgical complications and worse prognostic results than patients with an accurate preoperative diagnosis.

Results

Six cases of thyroid lymphoma were retrospectively reviewed: 4 diffuse large B-cell lymphomas and 2 MALT lymphomas. Of these, 2 were correctly preoperatively identified by fine-needle aspiration biopsy and 4 were an unexpected finding at histology: 3 cases of total thyroidectomy carried out for huge hypothyroid goiter in patients affected by Hashimoto's thyroiditis and in 1 case of total thyroidectomy carried out for anaplastic carcinoma in a patient affected by Hashimoto's thyroiditis.

Conclusions

In our experience, a correct preoperative diagnosis was extremely difficult (33%). In patients who underwent fine-needle aspiration, a correct diagnosis was made in 66% of cases. All patients with stage IE lymphoma who underwent total thyroidectomy had equivalent surgical complications and prognosis.

Whole-body (18)F-FDG PET/CT in primary non-Hodgkin's lymphoma of the thyroid associated with Hashimoto's thyroiditis and bilateral kidney infiltration

An 82-year-old female patient with hypothyroidism and Hashimoto's thyroiditis noted three years ago to have a small asymmetric goiter (left > right). Nevertheless, a rapid growth of the thyroid over 3-6 months caused dysphagia and shortness of breath. Ultrasound and a thyroid gammagram showed an image consistent with multinodular goiter with a hyperfunctioning nodule in the right lobe. Due to the history of Hashimoto's thyroiditis and a rapid increase in size of the thyroid gland, diagnoses of thyroid lymphoma and anaplastic thyroid cancer were considered. Thyroidectomy was attempted at an outside facility to relieve compressive symptoms. Fine needle aspiration was insufficient for diagnosis, and the product of thyroidectomy confirmed the diagnosis of diffuse large B-cell lymphoma. A positron emission tomography/computed tomography scan was performed in our institution for staging, revealing nodal and extranodal metastasis. Chemotherapy using cyclophosphamide, vincristine and dexamethasone (COP modified) led to a dramatic response of the tumor and a complete resolution of compressive symptoms.

Management of non-Hodgkin's lymphoma of the thyroid: the Royal Marsden Hospital experience

A retrospective review was conducted of patients treated for thyroid non-Hodgkin's lymphoma (TNHL) at the Royal Marsden Hospital between 1936 and 1996 to determine the effect of radiotherapy (RT) on outcome. 91 patients were identified from the Thyroid Unit Database. There were 77 females and 14 males with a median age of 65 years (range 22-87 years). RT was delivered according to two separate policies: (1) involved field radiotherapy (IFRT) to the thyroid bed and cervical lymph nodes; (2) extended field radiotherapy (EFRT) covering the thyroid bed, cervical and mediastinal lymph nodes. 89 patients received RT as part of definitive treatment following surgery, to a dose of approximately 40 Gy. 25 patients received IFRT and 64 patients EFRT. 27 patients received cytotoxic chemotherapy. 18 patients (72%) treated with IFRT died of TNHL with a median relapse free survival (RFS) of 10 months and a median overall survival (OS) of 21 months. In contrast, only 29 patients (46%) treated with EFRT died of TNHL with a median RFS of 76 months (p = 0.01 for RFS with respect to IFRT and p = 0.04 for OS). Significantly more patients treated with IFRT relapsed locally (52% vs 27%). There was no difference in the rates of systemic relapse (20% vs 22%). EFRT alone for Stage I, but not for Stage II disease, yielded acceptable rates of local control and disease free survival with doses of at least 40 Gy. These historical data strongly support the addition of combination chemotherapy to the treatment regimen in all patients with Stage II disease. Indeed, in recent years this has become the standard of care for all cases of thyroid lymphoma unless the histology is of marginal zone type (mucosa associated lymphoma tissue (MALT) lymphoma).

Clinical presentation and treatment of non-Hodgkin's lymphoma of the thyroid gland

BACKGROUND

Non-Hodgkin's lymphoma (NHL) of the thyroid is a rare malignancy. The traditional approach to curative treatment of localized (stages I and II) NHL of the thyroid gland is surgical resection. The recent success of multimodality chemoradiotherapy suggests that surgery should be reserved for providing a tissue diagnosis or relief from acute airway obstruction. It is questionable whether this has made an impact on treatment approaches.

METHODS

Retrospective chart review was conducted for all cases of localized NHL of the thyroid gland treated at Roswell Park Cancer Institute between January 1970 and January 1999.

RESULTS

Ten patients (8 women, 2 men) with a mean age of 56.8 years were identified. Nine patients (90%) presented with a neck mass; seven patients (70%) had a history of Hashimoto's disease. Nine patients (90%) had extensive investigations to rule out extrathyroidal disease. All patients were treated with either a total thyroidectomy (eight patients) or a thyroid lobectomy (two patients). Nine (90%) were initially treated outside of Roswell Park Cancer Institute and referred secondarily for consideration of further therapy. Adjuvant therapy consisting of cyclophosphamide-based chemoradiotherapy was administered to nine patients. Overall survival was 80% at a mean follow-up of 8.6 years with a disease-specific survival rate of 100%.

CONCLUSIONS

A review of the literature suggests that fine needle aspiration (FNA) with flow cytometry and immunohistochemistry can be used to accurately diagnose NHL of the thyroid gland. Open biopsy should be reserved for cases where this technique is not available or where the diagnosis can not be confirmed by FNA alone. Extrathyroidal NHL should be ruled out by chest x-ray, CT scan of the abdomen, and bone marrow biopsy. Further review suggests that the most efficacious therapy is systemic chemotherapy in combination with radiation for local control. Debulking surgery should be used only to provide relief from acute airway obstruction.