Hyperdensity at CT was due to the high hemoglobin content of retracted clot or sedimented blood. The various patterns seen can be related to sequential changes occurring in blood following hemorrhage. Should I worry about dense breast tissue? Being told you have dense breast tissue should not cause undue anxiety. If you have dense breast tissue, this means you have a higher proportion of glandular breast tissue to fatty tissue. Having dense breast tissue can make it more difficult to see breast cancer on a mammogram.
Are breast nodules cancerous? Although any lump formed by body cells may be referred to technically as a tumor. Not all tumors are malignant cancerous.
Following are examples of the most common benign breast conditions which produce lumps. How big is a 6mm nodule? They appear as round, white shadows on a chest X-ray or computerized tomography CT scan. Lung nodules are usually about 0. A larger lung nodule, such as one that's 30 millimeters or larger, is more likely to be cancerous than is a smaller lung nodule. What does cancer look like on an ultrasound? The images from a breast ultrasound are in black and white. Cysts, tumors, and growths will appear dark on the scan.
The majority of breast lumps are noncancerous, so more testing is needed to determine whether the lump is malignant. Does Spiculated mean cancer? Cancers appear spiculated because of direct invasion into adjacent tissue or because of a desmoplastic reaction in the surrounding breast parenchyma. Even at autopsy, the prevalence of thyroid nodules is high with multiple thyroid nodules seen in Thyroid nodules are ubiquitous but thyroid malignancy is rare with just 1 of 20 clinically detected nodules being malignant.
This justifies against the use of screening US for thyroid nodules in the general population. Controversy exists in many areas of management of thyroid nodules, including the most cost-effective approach in their diagnostic evaluation. Practice guidelines from several expert groups such as the American Association of Clinical Endocrinologists, the American Thyroid Association and the Society of Radiologists in Ultrasound attempt to address them.
However, there is still a lack of consensus on certain key areas. A thyroid nodule is defined as a discrete lesion within the thyroid gland that is radiologically distinct from the surrounding thyroid parenchyma [ 6 ] Fig.
Pathologically, they are classifiable into 5 types with distinct histologic features: hyperplasic, neoplastic, colloid, cystic and thyroid nodules [ 7 ]. Fundamental to their evaluation is differentiating medical from surgical disease and identifying the odd malignant one.
Clinical information may often give a clue to this. Nodules increasing in size are suspicious for malignancy, but lesions with rapid increase in size over a few hours are likely to be haemorrhagic. Haemorrhagic changes are more commonly encountered in malignant than benign nodules [ 8 ]. A benign multinodular goitre MNG grows in size over the years but malignancy typically grows in weeks.
Rapid growth during levothyroxine therapy is especially suggestive of cancer [ 2 ]. Even thyroiditis can cause rapid increase in size but the ancillary findings usually enable the differentiation. Symptoms from mass effect such as airway compression, hoarseness, and dysphagia are more often seen with MNG.
However, if these symptoms are seen in the absence of MNG, invasive forms of thyroid carcinoma are likely. Most of the well-differentiated thyroid carcinomas DTC are smaller and are unlikely to cause alarming symptoms. Any lesion within the thyroid gland that is radiologically distinct from the surrounding thyroid parenchyma qualifies as a thyroid nodule. High-resolution ultrasound can detect much smaller nodules.
The best initial laboratory test of thyroid function in a patient with thyroid nodule is serum thyroid stimulating hormone TSH. If a patient is not euthyroid, the diagnosis points towards a benign functional disorder, such as Hashimoto thyroiditis or a toxic nodule. A single, non-stimulated calcitonin measurement can be used in the initial workup of thyroid nodules as a marker for tumours of parafollicular cell origin [ 3 ].
High-resolution US is the most sensitive test available to detect thyroid lesions, measure their dimensions, identify their structure, and evaluate diffuse changes in the gland [ 3 ]. We scan the patient in a supine position with the neck hyperextended. In the first stage, the shape of the gland and the size of both lobes 3 dimensions and the anterior-posterior thickness of the isthmus are measured and the continuity of the thyroid capsule is confirmed.
The normal thyroid gland is uniformly echogenic relative to the strap muscles of the neck Fig. Thyroid nodules are identified and their various gray scale and Doppler interrogation characteristics are assessed for the risk of malignancy. This gives better orientation for the referring clinician as well as the for the radiologist doing the biopsy, and makes future comparisons at follow-up US more reliable and practical.
The neck is then screened for lymph nodes. Images of the nodules are stored in both axial and longitudinal planes and the diameter is recorded along all 3 axes, preferably on a single screen shot. Transverse grayscale mode image of a normal thyroid gland that is uniformly echogenic relative to overlying strap musculature arrows a. In comparison, b shows a thyroid gland with heterogeneous parenchymal echotexture and diffuse enlargement consistent with thyroiditis.
This patient had Graves disease. Tissue harmonic imaging, three-dimensional US and compound imaging can add value to routine US evaluation [ 10 ]. However, currently the use of CEUS is restricted to definition of the size and limits of necrotic zones after US-guided ablation procedures.
There is considerable overlap between the appearance of benign and malignant nodules and no single imaging feature can be considered pathognomonic. However, the simultaneous presence of 2 or more suspicious sonographic findings increases the risk of thyroid malignancy [ 13 , 14 ]. The following discussion comments on the relative value of the various US features of thyroid nodules in suspecting thyroid malignancy.
The patterns of calcifications seen in the thyroid are: microcalcifications, rim calcifications and coarse calcifications Figs. Compared with a non-calcified predominantly solid nodule, the presence of microcalcifications increases the cancer risk three-fold, and coarse macro-calcifications increase cancer risk two-fold [ 15 ].
The major drawback is the low sensitivity In comparison, coarse calcifications are less specific for malignancy as they are more frequently seen in benign nodules of multinodular goitre than in malignancy Fig.
The limitation of this US feature that needs to be kept in mind while interpreting images is the low sensitivity with coarse calcifications noted in 9.
This grayscale image of the left lobe of the thyroid along its long axis in a patient with multinodular goitre shows a nodule with coarse chunky calcification arrow. At histology, this was found to be benign. However, coarse calcifications when present in a solitary nodule are highly suspicious for malignancy. These images show microcalcifications in various thyroid pathologies. Although one of the most specific US features of malignancy, microcalcifications may also be seen in benign conditions.
At histology, this was diagnosed as a follicular adenoma. Surgery confirmed multifocal papillary thyroid carcinoma. An invasive papillary carcinoma. Both coarse and microcalcifications are seen in this nodule.
At colour Doppler interrogation b there is chaotic vascularity in the entire nodule. Examples of eggshell calcifications. This was a follicular adenoma at surgical excision. Pathologically they correspond to clusters of psammoma bodies [ 16 ]. Traditionally a hallmark of papillary thyroid carcinoma PTC , microcalcifications are also seen in benign lesions such as hyperplastic nodular goitre, Graves disease or lymphocytic thyroiditis.
Inspissated colloid in benign thyroid lesions may mimic microcalcifications in thyroid malignancies, but the former can be distinguished from the latter if the comet tail or reverberation artefacts are appropriately demonstrated Fig. The person performing the US scan needs to give due attention to this technical aspect to avoid misinterpretation. Coarse calcification manifests as echogenic focus with posterior shadowing. It may appear as spicules, fragmented plates, or granular deposits.
They represent dystrophic amorphous deposits of calcium in fibrous tissue or necrotic material. When seen in a solitary nodule, some groups recommend surgery, regardless of the result of fine-needle biopsy FNB [ 18 ]. Coarse calcifications may coexist with microcalcifications in papillary cancers, Fig.
Eggshell-like rim calcification Fig. Although formerly considered a feature of benignity, eggshell calcifications have been reported in thyroid cancers, mostly in papillary carcinoma and rarely in follicular carcinoma [ 21 ].
Various histology proven benign thyroid nodules. The isoechoic nodule is seen better in the transverse section TS and the echogenic one in the longitudinal section LS.
Besides the echotexture that favours benignity in both these nodules, they also show a well-defined hypoechoic halo that strongly favours benignity. Such nodules are usually benign and do not need biopsy.
Thyroid cancer is not common in predominantly cystic nodules and purely cystic nodules are almost never malignant. This appearance is diagnostic of a colloid cyst. Most thyroid nodules, both malignant and benign, have ovoid-to-round shape and a well-defined smooth margin.
Iso- or hyperechoic nodules may show a hypoechoic halo representing a pseudocapsule of fibrous connective tissue or compressed thyroid tissue and vessels Fig.
A complete, uniform halo around a nodule Fig. Such a nodule is 12 times more likely to be benign than malignant. Even if the halo is incomplete, it is 4 times more likely to be benign [ 23 ]. The nodule margins are described as well-defined regular, well-defined irregular or ill-defined [ 4 ].
Irregular margins Fig. The irregular spiculated or microlobulated margin is suggestive of malignancy; an ill-defined margin can be seen in both benign and malignant nodules [ 17 ]. There is considerable ambiguity in the interpretation of the nodule margin. The distinction between irregular and ill-defined margins is the subject of some debate. It has the highest interobserver variability among all the routinely evaluated sonographic features of thyroid nodule [ 24 ].
Some of this ambiguity may be unarguably attributed to the type of US probe used. With high-resolution probes, a previously described blurred margin could actually be a spiculated margin with sharp demarcation or a poorly defined margin where the tumour cannot be discriminated from the normal parenchyma.
Despite the subjective variations in margin interpretation, an irregular margin is a useful marker of malignancy with high accuracy, specificity and positive predictive value of The sensitivity is once again low at Images from a patient with multifocal papillary thyroid carcinoma are shown here.
Both nodules show irregular spiculated outlines, are solid and hypoechoic with few microcalcifications. The nodule in b is taller than wide.
The centrifugal tendency in tumour growth does not necessarily occur at a uniform rate in all dimensions. Hence malignant nodules can be taller than they are wide Fig. Several imaging tools in oncology are based on assessment of the difference in vascular signatures between malignant and benign tumours.
The early descriptions on the patterns of vascularity in thyroid nodules Fig. Type III was considered highly suggestive of malignancy. Hence, the current generation of scanners tend to show some degree of internal vascularity in most of the solid thyroid nodules, dissipating the initial enthusiasm with Doppler interrogation of thyroid lesions. Despite extensive overlap in the colour Doppler appearance of benign and malignant thyroid nodules, a predominantly peripheral flow pattern is considered as a feature of a benign nodule, and a malignant nodule tends to have a predominantly central chaotic blood flow.
Patterns of vascularity in thyroid nodules. The nodule in a with markedly chaotic central and peripheral vascularity is suspicious for malignancy also note the internal microcalcification ; the peripheral vascularity in the isoechoic nodule in b is a feature of benignity. On greyscale imaging, the well-defined nodule in c with a hypoechoic halo and honeycomb appearance is almost certain to be a benign lesion.
However, at colour Doppler imaging d the nodule shows both central and peripheral vascularity. The greyscale and colour Doppler imaging features of this nodule are contradictory. At biopsy, it was a benign nodule. The texture of a nodule is a reflection of its internal architecture and contents. Nodules may be purely cystic Fig. Solid composition of a nodule is the US feature with highest sensitivity for malignancy However, it has a low positive predictive value in that a solid nodule has only a Doctors can perform tests and sometimes surgical biopsies to determine whether a breast lump is benign or malignant.
An individual may a develop a breast nodule in any part of her breast tissue. For example, one woman may develop one under the nipple while another may discover one in the breast tissue near her armpit. These lumps can be any size. A woman may notice a breast nodule that is the size of a pea or a lump that is larger than an egg. Interestingly, most people think of women when breast nodules and breast cancer are discussed. They can, however, affect men too. For this reason, a person of either gender should see a doctor right away upon discovering a breast-area lump.
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