THYROID HEMANGIOMA

Discussion

Thyroid hemangiomas are extremely rare, and there are only a few cases reported in literature reviews. Most thyroid hemangiomas are not palpable and are diagnosed incidentally during imaging examinations. A hemangioma is a benign vascular tumor of 2 common types, capillary and cavernous, based on the size of the vessels involved. In most cases, thyroid hemangiomas are secondary to trauma or fine-needle aspiration biopsy. Secondary hemangiomas have been described as pseudomalformations, representing vascular proliferation after organization of a thyroid hematoma.Two case reports described exuberant vascular proliferation in the thyroid occurring secondary to fine-needle aspiration. Organization of the hematoma generally results in complete resolution, but it can give rise to vascular and fibroblastic proliferative changes that resemble a cavernous hemangioma. Our patients had no history of trauma, fine-needle aspiration, biopsy, or other invasive procedures in the neck; therefore, we believe that our cases were primary thyroid hemangiomas. Primary hemangiomas are extremely rare developmental anomalies resulting from the inability of the angioblastic mesenchyme to form canals. Previous studies reported that preoperative diagnosis of a thyroid hemangioma is difficult because there are no specific pathognomonic findings on sonography, fine-needle aspiration cytologic examination, or even CT. Heterogeneous signal intensity and a serpentine pattern on magnetic resonance imaging are considered highly suggestive of cavernous hemangiomas. However, there are a few reports of sonographic findings of hemangiomas in other superficial organs such as the breast. These studies reported that hemangiomas were lobulated, well-circumscribed masses, usually with heterogeneous or complex echogenicity due to the presence of multiple vascular channels and phleboliths. Our cases of thyroid hemangiomas showed well-circumscribed hypoechoic lesions with internal multiple linear septations on sonography, which were very similar to previously reported sonographic findings of hemangiomas. Another sonographic characteristic of a superficially located hemangioma is the compressibility of the blood-filled lesion unless it is fully thrombosed.  During the sonographic examinations, our lesions were compressible under the probe, and the lesion volume decreased after the bloody content was aspirated on fine-needle aspiration. We think that these lesions were vascular malformations such as hemangiomas based on the characteristic sonographic findings and confirmation of bloody content during fine-needle aspiration.

Innumerable internal septations on sonography may be related to the presence of multiple small vascular channels seen pathologically in hemangiomas, and large blood-filled spaces or sinuses have been previously reported in cavernous hemangiomas.Our cases were pathologically confirmed to be cavernous hemangiomas after surgery. Pathologically, cavernous hemangiomas are typically discrete multiloculated lesions containing evidence of hemorrhage in various stages of evolution. They lack smooth muscle and elastic fibers and are lined by a single layer of endothelium and differing quantities of subendothelial fibrous stroma. In most reported series, cavernous hemangiomas underwent periodic rapid growth, but in our first case, there was no interval change on follow-up sonography after 6 months or 1 year.

Coarse calcifications are often suggested to be a reliable sign of hemangiomas. However, in our cases, there was no sign of calcifications in the lesions on sonography or CT. Fine-needle aspiration cytologic examination seems to be inconclusive in the diagnosis of hemangiomas because it reveals only blood. Multiple fine-needle aspiration biopsies have not been shown to be useful in obtaining sufficient cellular material. However, we think that confirmation of bloody content by aspiration could be very helpful for preoperative diagnosis of thyroid hemangiomas when combined with characteristic sonographic findings. Core needle biopsy is usually contraindicated in hemangiomas because of the high risk of bleeding, but many hemangiomas have been diagnosed by core needle biopsies in intramuscular sites and the breast, and some authors suggest that core needle biopsy is a safe diagnostic procedure for hemangiomas. The definite diagnosis of a thyroid hemangioma is based on histologic findings. Complete surgical excision is usually recommended when a hemangioma is diagnosed.

Although there is the widespread perception that preoperative diagnosis of thyroid hemangiomas on sonography is difficult because there are no specific pathognomonic findings, we suggest that a more careful interpretation of sonograms with reference to characteristic imaging findings, such as a well-circumscribed hypoechoic structure with innumerable internal septations, may lead to a precise preoperative diagnosis of a thyroid hemangioma. In addition, although fine-needle aspiration cytologic results are usually insufficient, confirmation of bloody content during aspiration can further support a diagnosis of a thyroid hemangioma.

The presence of heterogeneous signal intensity and a serpentine pattern on magnetic resonance imaging is usually considered diagnostic for hemangiomas. Other imaging modalities such as single-photon emission CT, digital subtraction angiography, and red blood cell scans can provide additional information in the diagnosis of hemangiomas; however, such examinations are often not performed routinely because of their high cost and nonavailability, as in the cases described here.

Accurate preoperative diagnosis allows better preoperative planning, and adequate preoperative characterization is very important because bleeding is common in hemangiomas; in one series, intraoperative blood loss was in excess of 2 L. A previous report emphasized the importance of ensuring that the integrity of a thyroid hemangioma is maintained to minimize blood loss during surgery. 

This report describes 2 cases of thyroid hemangiomas that were diagnosed on sonography. These cases demonstrate that thyroid hemangiomas can be diagnosed correctly by sonography with or without confirmation of bloody content in the lesions by fine-needle aspiration.

ADNEXAL FINDINGS in ECTOPIC PREGNANCY and TUBAL RUPTURE and HCG LEVELS

Discussion

There have been major advances in ultrasound equipment in the past 2 decades. The resulting improved resolution raises the question of whether the sonographic findings of ectopic pregnancy described in the early days of transvaginal sonography still apply today. It is possible that improved resolution has resulted in earlier identification of adnexal abnormalities, with a corresponding change in the distribution of imaging findings. Our study addresses this question and provides an updated understanding of the imaging characteristics of ectopic pregnancy and their relationship to fallopian tube rupture.

We found that the percentage of ectopic pregnancies with a yolk sac or cardiac activity was lower than previously reported. Embryonic cardiac activity was found in fewer than 10% of our patients, similar to a recent report  but much lower than in earlier series, in which up to 24% of ectopic pregnancies had cardiac activity.  The ectopic pregnancy in more than half of our patients appeared as a non-specific adnexal mass, which may have represented a blood clot in some cases. Our study confirms the previously published important point that, in a small number of patients, free fluid may be the only sonographic finding of ectopic pregnancy.

In the early 1990s, color Doppler imaging was suggested as a valuable adjunct for the diagnosis of ectopic pregnancy.  However, we found color Doppler imaging to be of little clinical value: there was no significant relationship between the color pattern and type of adnexal mass, and the addition of color Doppler imaging to the examination did not improve the ability to predict tubal rupture.

Among our patients who underwent surgery within 1 day of the study sonogram, 25.2% proved to have tubal rupture. However, the overall rate of tubal rupture is likely to be much lower, since the women who underwent surgery were not representative of our entire group. Although our study methods do not allow us to determine the overall rate of tubal rupture with ectopic pregnancy, our results do permit us to conclude, as had been noted previously, that sonographic findings are not reliable predictors of rupture. No  single adnexal mass appearance or color Doppler characteristic correlates with the presence or absence of tubal rupture. Only the presence of a moderate-to-large amount of free intraperitoneal fluid was significantly associated with a ruptured fallopian tube, but the finding of this amount of free fluid had poor sensitivity, specificity, and positive predictive value for tubal rupture.

The role of hCG in the diagnosis of ectopic pregnancy is widely debated in the literature. Our study, similar to others,  shows that hCG levels vary widely in women with ectopic pregnancy, from less than 10 mIU/mL in one of  our patients to greater than 100,000 mIU/mLin another, and reinforces the fact that there is no lower-level hCG cutoff value with ectopic pregnancy. The average hCG value increased as the grade of the adnexal mass increased, with the highest average hCG level found in those with cardiac activity, which also confirms other reports.  However, the hCG level did not correlate with the presence or absence of tubal rupture, so this serum measurement has little clinical value if an adnexal mass is seen on sonography.

This study had a few limitations. Measurements of nonspecific adnexal masses were somewhat subjective, since the borders of the masses were not always clear. In particular, some of the poorly defined masses may have represented blood clots, which often do not have discrete margins and may be difficult to measure accurately. Another limitation was that some patients had more than 1 sonographic examination performed before the time of diagnosis. We used the transvaginal sonogram obtained closest to the point of treatment, which may have biased this report toward larger and more advanced adnexal findings. Additionally, some of our patients did not have either surgical or pathologic proof of their ectopic pregnancies but were treated medically.

Vector Tissue Doppler Ultrasound Effective In Imaging Muscle, Tendon Motion

Scientists have developed a new approach that utilizes a Doppler ultrasound for quantifying muscle kinematics. The new technology, which has been designed to image muscle and tendon motion during dynamic tasks, can provide a complementary methodological tool for biomechanical studies in a clinical or laboratory setting. Injured and painful joints feature complicated dynamics the understanding of which can help clinicians figure out how to address a variety of conditions. To visualize the processes involved in muscle and tendon dynamic tasks, the patient has to be imaged while using the injured joint. The investigators have developed an innovative vector tissue Doppler imaging (vTDI) technique that can be used to measure musculoskeletal contraction velocity, strain, and strain rate with submillisecond temporal resolution during dynamic activities using ultrasound. The researchers from George Mason University (Fairfax, VA, USA; www.gmu.edu) have devised the new technology that uses existing modalities to provide a comprehensive picture as to how the musculoskeletal parts of the leg function. Little white balls are fixed to specific points all over the patient’s body and a Doppler ultrasound probe is attached to the leg. The patient is then asked to perform a number of tasks while the ultrasound is recording and cameras monitor the balls to determine exactly how the individual is moving. Fusing the two modalities together provides a new ability to optimize the effectiveness of biomechanical studies. Moreover, other techniques, such as electromyography (EMG), can be used in conjunction to gain additional data. The study’s findings were published in an open access article with a video in September 2013 in the journal JoVE. The aim of this early study was to investigate the repeatability and potential applicability of the vTDI technique in measuring musculoskeletal velocities during a drop-landing task,in healthy subjects. The vTDI measurements can be performed concurrently with other biomechanical techniques, such as three-dimensional (3D)motion capture for joint kinematics and kinetics, EMG for timing of muscle activation and force plates for ground reaction force. Integration of these complementary techniques could lead to a better understanding of dynamic muscle function and dysfunction underlying the pathogenesis and pathophysiology of musculoskeletal disorders. Diagnostic ultrasound can enable direct imaging of muscle and tendons in real time, and therefore is an attractive alternative for measuring musculoskeletal dynamics and function during ADL. Ultrasound-based quantitative measures of muscle morphology and architecture, such as muscle thickness, length, width, cross-sectional area (CSA), fiber pennation angle and fascicle length have been widely used. Image-processing methods have recently been employed to assess and quantify these quantitative measures during dynamic tasks. These advances have enabled a new methodological approach to understanding in vivo muscle function. However, these methods have primarily relied on using conventional grayscale (or B-mode) ultrasound imaging, and therefore have not fully exploited the possibilities of ultrasound to measure tissue velocities, strain, and strain rate using Doppler principles, that have been shown to be valuable in evaluating cardiac muscle function. The vTDI technique can make measurements of muscles and tendons during highly dynamic tasks (e.g., drop-landing, gait) at high frame rates. The investigators have implemented this method on a commercially available ultrasound system with a research interface, enabling this study to bemade in a clinical setting. Vector TDI is based on estimating the resultant velocity vector from Doppler velocity measurements taken from two or more independent directions. An ultrasound system with a research interface was used for developing vTDI. The research interface allowed low-level beam forming and pulse sequence control using a software development kit (SDK). A 5–14 MHz linear array transducer, consisting of 128 transducer elements and with a 38-mm field-of-view was used. The research interface was employed to split the array transducer into two transmit and receive apertures and steer the receive beams by 15° with respect to the normal. The transmit beam was focused in the region of interest (e.g., muscle belly). Transmit and receive apertures were set to 32 elements.

Image: Researchers have put together a system that uses existing technologies to give a detailed view of how the musculoskeletal components of the leg function (Photo courtesy of George Mason University).

VTI on ARFI: A NEW TECHNIQUE for BENIGN and MALIGNANT THYROID NODULES

Abstract


Objectives—Acoustic radiation force impulse elastography is a newly developed ultrasound elasticity imaging technique that included both Virtual Touch tissue quantification and Virtual Touch tissue imaging (VTI; Siemens Medical Solutions, Mountain View, CA). This study aimed to evaluate the usefulness of VTI in differentiating malignant from benign thyroid nodules.

 Methods—This study included 192 consecutive patients with thyroid nodules (n = 219) who underwent surgery for compressive symptoms or suspicion of malignancy. Tissue stiffness on VTI elastography was scored from 1 (soft) to 6 (hard). The VTI scores between malignant and benign thyroid nodules were compared. The intraobserver and interobserver agreement for VTI elastography was also assessed.

Results—On VTI elastography: score 1 was found in 84 nodules (all benign); score 2 in 37 nodules (3 papillary carcinomas and 34 benign nodules); score 3 in 25 nodules (1 medullary carcinoma, 6 papillary carcinomas, and 18 benign nodules); score 4 in 53 nodules (50 papillary carcinomas and 3 benign nodules); score 5 in 17 nodules (14 papillary carcinomas and 3 benign nodules); and score 6 in 3 nodules (all papillary carcinomas). A VTI elasticity score of 4 or greater was highly predictive of malignancy (P< .01), and the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 87.0% (67 of 77), 95.8% (136 of 142), 91.8% (67 of 73), 93.1% (136 of 146), and 92.7% (203 of 219), respectively. The κ values were 0.69 for intraobserver agreement and 0.85 for interobserver agreement.

Conclusions—Virtual Touch tissue elasticity imaging has great potential as an adjunctive tool combined with conventional sonography for differential diagnosis between benign and malignant thyroid nodules.

RTE of BENIGN and MALIGNANT CERVICAL LESIONS

Objectives—This study aimed to evaluate the clinical value of ultrasound elastography in the differential diagnosis of benign and malignant cervical lesions and to compare the accuracy of the elasticity score and strain ratio in differentiating cervical lesions.
Methods—B-mode sonography and ultrasound elastography were performed on 84 cervical lesions (40 benign and 44 malignant) in 84 patients. All of the images were obtained transvaginally. The elasticity score was determined by a 5-point scoring method. Calculation of the strain ratio was based on a comparison of the average strain measured in the lesion with the adjacent tissue of the same depth, size, and shape. The
findings were compared with histopathologic results. With the use of receiver operating characteristic curves, the diagnostic value of the elasticity score and strain ratio methods was determined.
Results—The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the elasticity score in the differential diagnosis of cervical lesions were 81.8%, 85.0%, 83.3%, 85.7%, and 81.0%, respectively, whereas those of the strain ratio were 90.9%, 90.0%, 90.5%, 90.9%, and 90.0%. A strain ratio cutoff value of 4.525 was used as a standard to distinguish benign from malignant lesions. The strain ratio values of malignant lesions were much higher than those of benign lesions (range, 4.85–8.91
versus 0.62–4.50). The differences were statistically significant (P < .01).

Conclusions—Ultrasound elastography is a promising technique that is easy and rapid to perform and can help identify cervical lesions that are likely to be malignant. It is obvious that the strain ratio yielded better results than the elasticity score. Both methods are semiquantitative, but quantification of the strain ratio is finer than that of the elasticity score.


Key Words—cervical lesions; elasticity score; gynecologic ultrasound; strain ratio; ultrasound elastography

HEART DEFECTS in FOETUSES and ULTRASOUND MISSINGS

NHÂN CA SARCOMA TÚI MẬT TẠI MEDIC (CA 243)

DISCUSSION

Sarcomas of the gallbladder are rare and represent  about 1.5% of all malignant gallbladder diseases. A variety of tumor types have been described including leiomyosarcoma, rhabdomyosarcoma, angiomyosarcoma, Kaposi’s sarcoma, malignant fibrous histiyocytoma, and synovial sarcoma [2]. Leiomyosarcoma of the gallbladder is an especially rare malignant tumor. By 1984, 105 cases of primary sarcomas of the gallbladder had been reported, with primary leiomyosarcomas accounting for 7% of them [3].

The diagnoses were established in accordance with the new World Health Organization classifications for soft tissue tumors and the most recent soft tissue criteria published. Leiomyosarcoma is defined as a malignant tumor composed of cells showing distinct smooth muscle features. In the macroscopy, leiomyosarcoma typically forms a fleshy mass, with colors varying from grey to white to tan. Large examples often display hemorrhage, necrosis or a cystic change. The typical histopathologic pattern of leiomyosarcoma is that of intersecting, sharply marginated groups of spindle cells. In the immunophenotype, desmin, h-caldesmon, and SMA were positive in a great majority of leiomyosarcomas. None of these are absolutely specific to smooth muscle and positivity for two of these markers were more supportive of leiomyosarcoma than positivity for one alone. Immunostains may be focally positive on CD34, epithelial membrane antigen (EMA), keratin and S100. A diagnosis should be made on the appropriate morphologic features, not only on the immunostains. In this case, immunopositive staining was strong for SMA and vimentin but the typical histopathologic pattern of leiomyosarcoma had appeared in the hematoxylin and eosin stain. Therefore other types of the sarcoma were excluded from the diagnosis.

Leiomyosarcoma is more frequent in women between the ages of 50 and 75 years and usually has a poor  prognosis. The presence of gallstones are invariable and the symptoms presented are those of chronic cholecystitis [4]. Histopathologically, the majority of these tumors are high grade and display an epithelioid morphology; but cases with features of well-differentiated leiomyosarcoma have been described.

According to the National Comprehensive Cancer Network clinical practice guideline in oncology ver. I. 2011, patients with a resectable intraabdominal sarcoma should undergo immediate surgical treatment with a grossly negative margin and and possible interoperative radiation therapy. The postoperative margin status was the most important factor contributing to long-term disease free survival [5]. Postoperative treatment options were dependent on the surgical outcomes and clinical, or pathological finding following surgery. Postoperative radiation therapy should be considered in patients with pathological findings of high grade disease following a negative margin resection (R0 resection) or for microscopic positive margins (R1 resection). For patients with unresectable or disseminated recurrences, preoperative RT and/or chemotherapy should be considered after a biopsy. Combination regimens with activity in soft tissue sarcoma include AD (doxorubicin, dacarbazine), AIM (doxorubicin, ifosfamide, mesna), MAID, and so on [6,7].

The single agents include dacarbazine, doxorubicin, epirubicin, gemcitabine, ifosfamide, liposomal doxorubicin and temozolomide [8,9].

The prognosis of sarcoma and leiomyosarcomas of the gallbladder is dismal, the five year survival rate being less than 5%. This is due to the fact that at the time of the diagnosis or surgery. Almost 75% of cases involve the liver [10]. 

Our patient was also diagnosed at an advanced stage, but he had no distant organ metastasis. Because R0 resection is expected in this case, an aggressive surgical approach was attempted. However, soon after, multiple liver metastasis and peritoneal seeding metastasis were detected in post-operative evaluations. Therefore additional aggressive multimodality treatments such as surgery with chemotherapy are the only way to increase the survival rate.

In conclusion, the five year survival rate of leiomyosarcoas of the gallbladder is less than 5%. However for young and healthy patients with leiomyosarcomas of the gallbladder, aggressive surgical treatment followed by adjuvant chemotherapy should increase the survival rate despite high mortality and morbidity. Because of limited experience with this disease,  there is no consensus about management. Further studies are needed to confirm the benefit of aggressive treatment for patients with leiomyosarcoma of the gallbladder. Also surgeons will have to tread very carefully in selection of candidates for surgical treatments.

Primary Leiomyosarcoma of Gallbladder, thesurgery.or.kr 407

PARASITIC THYROID NODULE

 Figure 1: Neck ultrasonography. The arrows show two submandibular nodes with thyroid tissue.

Abstract

Introduction

The presence of benign thyroid tissue that is located on the side of the neck is extremely rare and not related to the development of the thyroid, and it is difficult to differentiate it from thyroid carcinoma metastasis.

The parasitic thyroid nodule occurs when thyroid tissue located  in the lateral neck has no relationship or association with the lymph nodes, and may be defined  as a thyroid nodule entirely separate from the thyroid or attached to it by a narrow pedicle, presenting the same

histology and in the same facial plane as the thyroid, and should not be associated with lymph nodes. 

Case presentation

A 40-year-old Brazilian man without significant past medical history presented with a large volume multinodular thyroid goiter that caused deformity and symptoms suggestive of cervical spine compression. He underwent a total thyroidectomy. His  thyroid function was normal. Ultrasonography showed a heterogeneous thyroid nodule measuring 3.7cm to the right from midline and 3.3cm to the left from midline that was associated with two nodules in the left submandibular area measuring 1.43cm and 1.52cm.

Fine needle aspiration confirmed the benign nature of the gland and thyroid tissue etiology of the two submandibular nodules, located in level II of the neck. Since the ectopic thyroid tissue in his lateral neck was suggestive of metastasis of occult primary thyroid carcinoma,the patient underwent a total thyroidectomy plus a left modified radical neck dissection with preservation of level I. The diagnosis of multinodular goiter associated with two parasitic thyroid nodules was confirmed by immunohistochemistry.

Conclusions

We conclude that the parasitic thyroid nodule should be included in the differential diagnosis of lateral neck masses. The diagnosis and differentiation of these nodules from metastatic adenopathies of differentiated thyroid carcinoma has important therapeutic and prognostic implications, and can lead to avoidance of unnecessary surgeries.

Introduction

Ectopic thyroid tissue is a failure of migration of the thyroid during the embryonic period [1].It can be present anywhere, from the foramen cecum, which is at the base of the tongue, tothe normal position of the thyroid, which is between the second and fourth tracheal rings [1].

Lesions are usually midline, and this position is the most frequent  presentation of ectopicthyroid tissue, presenting in 90% of cases [2]. The terms, accessory thyroid gland or tissue,have been used in these instances.

The presence of benign thyroid tissue located on the side of the neck is extremely rare andnot related to the development of the thyroid, and it is difficult to differentiate from thyroidcarcinoma metastasis [3].

The parasitic thyroid nodule occurs when thyroid tissue located  in the lateral neck has norelationship or association with the lymph nodes, and may be defined  as a thyroid noduleentirely separate from the thyroid or attached to it by a narrow pedicle, presenting the samehistology and in the same facial plane as the thyroid, and should not be associated with lymph nodes [1]. We report the case of a parasitic thyroid nodule in a patient with multinodulargoiter that simulated metastasis of an occult primary thyroid carcinoma. 

Case presentation

A 40-year-old Brazilian man without significant past medical history presented to our institution in 2011 with a large volume multinodular thyroid goiter that caused deformity and symptoms suggestive of cervical spine compression. He underwent a total thyroidectomy. His

thyroid function was normal. Ultrasonography showed a heterogeneous thyroid nodule measuring 3.7cm to the right from midline and 3.3cm to the left from midline that was associated with two nodules in the left submandibular area measuring 1.43cm and 1.52cm (Figure 1).

Fine needle aspiration confirmed the benign nature of the gland and the thyroid tissue etiology of two submandibular nodules located in level II in his neck. The thyroglobulin levels were not measured in fine needle aspiration. A frozen section of two submandibular masses was performed before thyroidectomy. As a result, ectopic thyroid tissue was noted, but the pathologist did not exclude the possibility of metastasis of occult primary thyroid carcinoma. Our patient underwent a total thyroidectomy, plus a left modified radical neck dissection with preservation of level I. The diagnosis of multinodular goiter associated with two parasitic thyroid nodules was confirmed by immunohistochemistry.

Microscopically, the goiter was composed of thyroid tissue with normo- and macroscopic follicles that contained colloid and a coated monolayer of cells with regular, uniform nuclei that were round to oval and had fine chromatin, as well as homogeneous eosinophiliccytoplasm. There were no papillary formations, psammoma bodies or nuclear atypia, such as clear core, slit or pseudo nuclear inclusions (Figure 2). The material did not have characteristics consistent with malignancy. Expression of thyroid transcription factor (TTF-1)and thyroglobulin on immunohistochemistry confirmed the thyroid origin of the goiter (Figure 3). The findings corresponded to a parasitic thyroid nodule. 

Figure 2 Microscopy of goiter showing no signs of goiter malignancy.

Figure 3 Immunohistochemistry of nodules. a) Expression of TTF-1; b) expression of thyroglobulin. 

Discussion

Thyroid tissue can be located in the lateral region of the neck under three circumstances.

First, thyroid tissue can be present when there is mechanical deployment of the tissue after thyroid surgery or cervical trauma; second, when parasitic thyroid nodules are present without associated lymph nodes; and third, when there are metastases of thyroid tissue inlymph nodes [1].

The nodules are the result of a parasitic growth of extracapsular nodular thyroid waste that becomes separated from a preexisting nodular goiter. It has been proposed that mechanical action of the cervical muscles over a nodular goiter could cause the separation of these thyroid residues [4]. Portions of goiter that protrude through the fascia can be cut by muscle pressure on the thyroid. This explains why the thyroid gland and parasitic nodules have the same histology and parasitic thyroid nodules have no evidence of malignancy [5,6].

Conclusion

We conclude that the parasitic thyroid nodule should be included in the differential diagnosis of lateral neck masses. The confirmation of a parasitic thyroid nodule requires that it is in the same fascial plane of the thyroid, has similar histology as the  thyroid, and cannot be associated with lymph nodes. This benign condition is considered to be rare, and it can cause a serious dilemma if there is suspicion of an occult primary thyroid carcinoma. The diagnosis and differentiation of these nodules from metastatic adenopathies of differentiated thyroid carcinoma have important therapeutic and prognostic implications, and may prevent unnecessary medical examinations or treatments in the future.

Why does Breast US Find Cancers Mammography doesn't?

Why does breast US find cancers mammography doesn't?

By Kate Madden Yee, AuntMinnie.com staff writerFebruary 20, 2014 -- Most breast cancers detected at screening ultrasound are not seen on mammograms, even in retrospect, which suggests that supplemental screening with ultrasound is beneficial for high-risk women -- especially those with dense tissue, according to a new study published in the February issue of Radiology.

More states in the U.S. are passing breast density notification laws that require women with dense breast tissue at mammography to be told of their status and that additional screening may be beneficial. Ultrasound is an attractive screening technology because it is widely available and does not require contrast or radiation, wrote the researchers from Seoul National University College of Medicine in South Korea.
No published studies have uncovered why mammography misses cancers that ultrasound finds, according to lead author Dr. Min Sun Bae and colleagues. So Bae's team reviewed the mammograms of women with breast cancers detected at screening ultrasound to determine why they had not been found at mammography.
"The majority of breast cancers detected at screening US are obscured by overlapping dense breast tissue at mammography," the authors wrote. "However, some cancers may have subtle or evident mammographic findings that were overlooked or misinterpreted, and other cancers may reside in an anatomic area that is difficult to detect with mammography" (Radiology, February 2014, Vol. 270:2, pp. 369-377).
The study included 335 ultrasound-detected cancers found between 2003 and 2011 in 329 women with dense breast tissue (BI-RADS density type 2 or higher). Five blinded radiologists reviewed the mammograms to determine whether the findings on negative mammograms should be recalled; three unblinded radiologists re-reviewed the mammograms to determine the reasons the cancers had been missed. The cancers recalled by the blinded radiologists were compared with the reasons they weren't detected, as determined by the unblinded radiologists.
Of the 335 cancers found by screening ultrasound, 63 (19%) were recalled by three or more of the five blinded radiologists, and 272 (81%) showed no mammographic findings that required immediate action. Of these 272 cancers, 131 (48%) were rated as normal by all five blinded radiologists, 82 (30%) were rated as normal by four of the five blinded radiologists, and 59 (22%) were rated as normal by three of the five.
In the unblinded review, 263 (78%) of the cancers were obscured by overlapping dense breast tissue, and nine (3%) were not found at mammography because of difficult anatomic location or poor positioning.
Finally, 63 (19%) of the 335 cancers found at ultrasound and missed at mammography were considered interpretive errors. Of these, 52 (82%) were subtle findings (46 asymmetries and six calcifications) and 11 (18%) were evident (six focal asymmetries, one distortion, and four calcifications).
In women with dense breast tissue, supplemental screening with ultrasound can find cancers that mammography misses, or those that are too subtle for mammography to identify alone, Bae and colleagues concluded.
"Our data support the idea that screening ultrasound can improve cancer detection in women with dense breasts who are at increased or normal risk," they wrote.