| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
|
by the American Institute of Ultrasound in Medicine J Ultrasound Med 29:111-115 • 0278-4297
The Tortoiseshell Pattern in One or Both Sides of the Submandibular Glands in Mucosa-Associated Lymphoid Tissue Lymphoma Is Related to Chromosomal Aberrations and the Disease ExtentDepartments of Laboratory Medicine (S.A., G.J., H.Ma., H.Mi.), Otolaryngology (K.O.), Pathology (N.N.), Internal Medicine, Section of Hematology (Y.Ogawa), and Dentistry and Oral Surgery (Y.Oh.), Tokai University School of Medicine, Isehara, Kanagawa, Japan; and Clinical Laboratory Center, Tokai University Hospital, Isehara, Kanagawa, Japan. (Y.Ogase). Address correspondence to Satomi Asai, MD, PhD, Department of Laboratory Medicine, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa 259-1193, Japan., E-mail: sa{at}is.icc.u-tokai.ac.jp
Objective. Lesions of mucosa-associated lymphoid tissue (MALT) lymphoma in the submandibular glands are localized or a part of systemic involvement in association with chromosomal aberrations. This series was undertaken to investigate the sonographic features of MALT lymphoma in the submandibular glands and their relationships with chromosomal aberrations and the disease extent. Methods. A total of 5 patients with MALT lymphoma without Sjögren syndrome in the submandibular glands were enrolled in this series. Patients underwent sonography of the submandibular glands with a high-resolution transducer before surgical biopsy of the main lesion. Sonographic characteristics of the lesions were described for their location, presence of a posterior echo, texture, and presence of an internal echo. Results. Sonography in all cases showed hypoechoic and solid masses with increased posterior echo enhancement. There was an arrangement of hypoechoic small compartments demarcated by hyperechoic contour lines, which had a tortoiseshell pattern. This pattern was classified into 2 types according to its location: a lesion in the right or left side and lesions in both sides of the submandibular glands, found in 3 and 2 patients, respectively. The latter 2 cases had chromosomal aberrations of t(11;18)(q23;q23) and t(12;18)(q22;q21), respectively, and were revealed as secondary organ involvement. Conclusions. The sonographic appearance of MALT lymphoma in the submandibular glands was characterized by the tortoiseshell pattern in both primary and secondary lesions. Detection of this pattern in both sides of the submandibular glands can be an indicator of chromosomal aberrations and systematic involvement of the disease.
Key Words: chromosomal aberration • infiltration • mucosa-associated lymphoid tissue lymphoma • sonography • submandibular glands Abbreviations: MALT, mucosa-associated lymphoid tissue
Mucosa-associated lymphoid tissue (MALT) lymphoma constitutes 7% to 8% of all B-cell lymphoma cases and up to 50% of primary gastric lymphoma cases, but it can develop in other sites, including the intestine, salivary glands, lung, head and neck, ocular adnexa, skin, thyroid, and breast.1 Subtypes of lymphoma in the salivary glands of patients with Sjögren syndrome and other autoimmune disorders are usually MALT lymphoma,2,3 whereas its histopathologic subtypes in those without such underlying disorders are various, with follicular lymphoma as the most common and MALT lymphoma on rare occasions.4,5 With recent advancement in ultrasound technology and devices, sonography has become widely used in the diagnosis of masses in the superficial organs, including the cervical area.6–9 Sonography of lymphomatous involvement of the salivary glands has been reported as showing hypoechoic or cystic masses, regardless of histopathologic subtypes.10–13 Different from previous reports, we reported a tortoiseshell appearance, an arrangement of hypoechoic compartments surrounded by hyperechoic lines, in a MALT lymphoma case without Sjögren syndrome.14 Mucosa-associated lymphoid tissue lymphoma is a low-grade and indolent type of B-cell lymphoma, its involvement being localized in a specific organ.1,15 Its clinical course is indolent, with a high response to therapeutic modalities, late relapses, and long overall survival. However, in some cases, chromosomal translocations of MALT lymphoma, such as t(11;18)(q21;q21) and t(1;14)(p22;q32), have been identified and reported to be often associated with systemic involvement.16,17 To further characterize the sonographic features of MALT lymphoma without Sjögren syndrome, we studied sonograms from 5 of those patients and investigated its association with chromosomal abnormalities and the disease extent.
Enrolled in this study were 5 patients with untreated MALT lymphoma in the submandibular glands who underwent sonographic examinations from January 2005 to April 2009 at Tokai University Hospital. They included a male patient and 4 female patients with a median age of 73 years (range, 56–78 years). None of these patients had a history of Sjögren syndrome. Sonography of their neck was performed with a real-time ultrasound scanner using 8- and 12-MHz linear array transducers (Aplio; Toshiba Medical Systems Co, Ltd, Tokyo, Japan). The patients underwent sonography of the submandibular glands followed by surgical biopsy of the main lesions. The sonograms were retrospectively reviewed by 2 independent observers, and the results were independently compared with those of the histopathologic examinations. Sonographic characteristics of the lesions in the submandibular gland were described for their location, presence of a posterior echo, texture, and presence of an internal echo. The sonographic characteristics were compared with the histopathologic and chromosomal analysis findings for the resected lesions.
Sonography of MALT lymphoma in the submandibular glands revealed a hypoechoic solid mass with increased posterior enhancement. Internally, there was an arrangement of small hypoechoic compartments demarcated by hyperechoic contour lines, which was described as the tortoiseshell pattern (Figure 1  ). This pattern was detected in one or both sides in 3 and 2 patients, respectively (Table 1).
Involvement of the submandibular glands by MALT lymphoma was diagnosed with histopathologic proof of lymphoma in the submandibular parenchyma. Histopathologic examinations of open biopsy specimens of the submandibular glands revealed lymphomatous involvement of the lesions with scattered vascular channels and fibrous bands (Figure 2 ). The histopathologic examinations of the 5 cases revealed basically the same findings except for their locations. The lymphoma cells were composed of uniformly small- to medium-sized cells with a round to slightly indented nucleus and clear cytoplasm. Lymphoepithelial lesions were occasionally observed. When the sonograms of the primary or secondary lesions in the submandibular glands were compared with the histopathologic findings, the hyperechoic lines or septumlike echoes that made the compartments corresponded to fibrous bands.
Both patients with lesions in both sides of the submandibular glands were found to have the chromosomal translocations of t(11;18)(q23;q23) and t(12;18)(q22;q21), respectively, and extraglandular lymphomatous involvement of the lungs or lymph nodes. On the other hand, the 3 patients with a lesion in only one side of the submandibular glands had normal karyotypes, and the disease was limited to the submandibular glands.
In all 5 cases of MALT lymphoma without Sjögren syndrome, sonography of the submandibular glands revealed the presence of swollen glands with a tortoiseshell pattern on one or both sides. The diagnosis of primary lymphoma of the submandibular glands can be made only with histopathologic proof of lymphoma in the submandibular parenchyma without any evidence of intraglandular nodal or extraglandular lymphomatous involvement. In 3 cases with MALT lymphoma, the lesions were limited to one side of the submandibular glands; thus, the diagnosis of primary lymphoma of the submandibular glands was suggested. In the other 2 cases, extraglandular lymphomatous involvement in the lungs or lymph nodes was shown, suggesting secondary lymphomatous involvement of the submandibular glands. Detection of a chromosomal translocation such as t(11;18) is confirmatory of the diagnosis of MALT lymphoma and is characteristic of extraglandular lymphomatous involvement of the lungs.16,17 Patients with Sjögren syndrome and other autoimmune diseases may have clinically overt MALT lymphoma in the salivary glands.2,18,19 In contrast, most patients who do not have this syndrome clinically have lesions in extrasubmandibular gland sites.1 In our series of MALT lymphoma of the submandibular glands in patients without Sjögren syndrome, we found both primary and secondary involvement of submandibular gland lesions. Sonography of the submandibular glands in all cases revealed the tortoiseshell pattern, an arrangement of hypoechoic small compartments demarcated by hyperechoic contour lines. This was supported by common histopathologic findings for the lesions in all cases. The appearance of the tortoiseshell pattern can be explained by indolent expansion of lymphomatous cells demarcated by residual fibrous tissues in the submandibular glands. To our knowledge, the tortoiseshell pattern has not been reported in other types of lymphoma in the cervical lymph nodes and salivary glands.6,14,20 Septum-like echoes have been observed in Hodgkin lymphoma, reflecting the histopathologic findings of prominent fibrous connective tissues and formation of a nodular structure surrounding each lymph node. It is frequently contiguous with an indentation of the contour, typically forming a contour or lobular pattern but not the tortoise-shell pattern.6,14 Of note in the findings from this series was that the only difference in the sonographic appearance between primary and secondary lesions of the submandibular glands in MALT lymphoma without Sjögren syndrome was disease involvement in either one or both sides of the glands, respectively. When this pattern is detected in both sides of the submandibular glands, one should consider a survey of extraglandular lymphomatous involvement such as the lungs and lymph nodes. To determine the possibility of chromosomal aberrations, chromosomal analysis of specimens from the lesions is also recommended. In summary, the sonographic appearance of MALT lymphoma lesions in the submandibular glands of patients without Sjögren syndrome is characterized by the tortoiseshell pattern in both the primary and the secondary lesions. The detection of this pattern in both sides of the submandibular glands can be an indicator of chromosomal aberrations and systematic involvement of the disease. Further studies with larger numbers of patients is warranted.
Received August 11, 2009, from the Departments of Laboratory Medicine (S.A., G.J., H.Ma., H.Mi.), Otolaryngology (K.O.), Pathology (N.N.), Internal Medicine, Section of Hematology (Y.Ogawa), and Dentistry and Oral Surgery (Y.Oh.), Tokai University School of Medicine, Isehara, Kanagawa, Japan; and Clinical Laboratory Center, Tokai University Hospital, Isehara, Kanagawa, Japan. (Y.Ogase). Revision requested September 9, 2009. Revised manuscript accepted for publication October 5, 2009.
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
Top
Abstract
Introduction
