Nasopharyngeal carcinoma CT: Difference between revisions
Homa Najafi (talk | contribs) No edit summary |
Homa Najafi (talk | contribs) |
||
| Line 16: | Line 16: | ||
==CT scan== | ==CT scan== | ||
[Location] CT scan may be helpful in the diagnosis of [disease name]. Findings on CT scan suggestive of/diagnostic of [disease name] include: | [Location] CT scan may be helpful in the diagnosis of [disease name]. Findings on CT scan suggestive of/diagnostic of [disease name] include: | ||
| Line 26: | Line 22: | ||
*[Finding 3] | *[Finding 3] | ||
CT and MR can be complementary in this regard: CT is superior for the study of bony structures and for the presence of cervical lymph nodes, while the MR provides a better assessment of the primary tumor location and of intracranial structures and retropharyngeal spaces. PET scan may assist in the accurate planning of radiotherapy treatment (RT). PET-CT scan can replace the traditional work-up for detection of distant metastatic disease Invasion of bone of the skull base can be imperceptible on computed tomography (CT) but denotes T3 stage. It is, thus, preferable that MR imaging be used for NPC staging.3,19,20 In the authors’ experience, the T1-weighted images in 3 planes, but particularly the coronal and sagittal plane, are excellent for evaluation of the normally hyperintense (fat signal) skull base marrow. When tumor abuts the skull base, loss of the fat signal indicates bone infiltration. Once this is determined, it is important to consider more extensive intracranial disease spread through the skull base foramina along cranial nerves or along the internal carotid artery. This disease spread is also best seen with MR imaging and designates T4 tumor. NPC may also spread laterally from the nasopharynx through the pharyngobasilar fascia or through the foramen of Morgagni to the parapharyngeal fat with or without skull base invasion. Parapharyngeal fat involvement, which is well seen on either CT or MR imaging owing to the fat’s low CT density and high T1 signal intensity on MR imaging, denotes T2 tumor. Further lateral spread through the superficial layer of the deep cervical fascia into the masticator space, however, upstages the tumor to T4 and is an independent prognostic factor for overall survival and local relapse-free survival.21 Because the masticator muscles are supplied by the mandibular division of the trigeminal nerve and are located inferior to the greater sphenoid wing, it is important to look for involvement of the foramen ovale for intracranial spread once masticator space involvement is determined. This involvement will not change tumor staging because intracranial spread is also T4, but it is important for radiation planning. | |||
All patients should be evaluated by a multidisciplinary team (consisting of surgeons, medical oncologists, and radiation oncologists). A chest x-ray and a CT scan of the chest (including the liver) should be performed to identify metastases. A CT/MRI examination should be done to assess local and locoregional disease. Extension into the parapharyngeal space, bone erosion, or intracranial involvement is seen only by CT/ MRI examination. Yu et al. [5] reported a 55% upstaging of T2 and a 56% upstaging of T3 patients when comparing staging done by CT scans versus plain x-rays. MRI is superior to CT in detecting infiltration along the pharyngobasilar fascia and retropharyngeal lymph nodes. CT scans are better to detect early bony invasion. CT and MRI have a low sensitivity (45% and 56% respectively) in evaluating residual disease after treatment; either could be used [6]. | |||
CT has long been used for staging NPC,especially for the detection of skull base tumor involvement with lytic or sclerotic lesions [6, 7], but it has now largely been replaced by MRI for primary and nodal staging. However, CT is still used for radiotherapy planning and, in some centers, is used together with PET using 18F-FDG. PET/CT has been shown to be of value in NPC staging, where the main advantage is for the detection of distant metastasis [8]. It is also used for monitoring patients after therapy and detecting NPC recurrence. | |||
NPC has a strong tendency for systemic metastases to the bone, chest, and/or liver, with up to 5% of patients having distant metastasis at presentation. M1 tumor staging determines stage IVC disease.7,27 Up to 30% of patients will have distant recurrence after radiation therapy.15,28 National Comprehensive Cancer Network (NCCN) practice guidelines recommend positron emission tomography– computed tomography (PET-CT) to evaluate for distant metastases when N2 or N3 disease is present. | |||
==Overview== | ==Overview== | ||
Revision as of 15:24, 6 March 2019
|
Nasopharyngeal carcinoma Microchapters |
|
Differentiating Nasopharyngeal carcinoma from other Diseases |
|---|
|
Diagnosis |
|
Treatment |
|
Case Studies |
|
Nasopharyngeal carcinoma CT On the Web |
|
American Roentgen Ray Society Images of Nasopharyngeal carcinoma CT |
|
Risk calculators and risk factors for Nasopharyngeal carcinoma CT |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Homa Najafi, M.D.[2]Faizan Sheraz, M.D. [3]
Overview
There are no CT scan findings associated with [disease name].
OR
[Location] CT scan may be helpful in the diagnosis of [disease name]. Findings on CT scan suggestive of/diagnostic of [disease name] include [finding 1], [finding 2], and [finding 3].
OR
There are no CT scan findings associated with [disease name]. However, a CT scan may be helpful in the diagnosis of complications of [disease name], which include [complication 1], [complication 2], and [complication 3].
CT scan
[Location] CT scan may be helpful in the diagnosis of [disease name]. Findings on CT scan suggestive of/diagnostic of [disease name] include:
- [Finding 1]
- [Finding 2]
- [Finding 3]
CT and MR can be complementary in this regard: CT is superior for the study of bony structures and for the presence of cervical lymph nodes, while the MR provides a better assessment of the primary tumor location and of intracranial structures and retropharyngeal spaces. PET scan may assist in the accurate planning of radiotherapy treatment (RT). PET-CT scan can replace the traditional work-up for detection of distant metastatic disease Invasion of bone of the skull base can be imperceptible on computed tomography (CT) but denotes T3 stage. It is, thus, preferable that MR imaging be used for NPC staging.3,19,20 In the authors’ experience, the T1-weighted images in 3 planes, but particularly the coronal and sagittal plane, are excellent for evaluation of the normally hyperintense (fat signal) skull base marrow. When tumor abuts the skull base, loss of the fat signal indicates bone infiltration. Once this is determined, it is important to consider more extensive intracranial disease spread through the skull base foramina along cranial nerves or along the internal carotid artery. This disease spread is also best seen with MR imaging and designates T4 tumor. NPC may also spread laterally from the nasopharynx through the pharyngobasilar fascia or through the foramen of Morgagni to the parapharyngeal fat with or without skull base invasion. Parapharyngeal fat involvement, which is well seen on either CT or MR imaging owing to the fat’s low CT density and high T1 signal intensity on MR imaging, denotes T2 tumor. Further lateral spread through the superficial layer of the deep cervical fascia into the masticator space, however, upstages the tumor to T4 and is an independent prognostic factor for overall survival and local relapse-free survival.21 Because the masticator muscles are supplied by the mandibular division of the trigeminal nerve and are located inferior to the greater sphenoid wing, it is important to look for involvement of the foramen ovale for intracranial spread once masticator space involvement is determined. This involvement will not change tumor staging because intracranial spread is also T4, but it is important for radiation planning.
All patients should be evaluated by a multidisciplinary team (consisting of surgeons, medical oncologists, and radiation oncologists). A chest x-ray and a CT scan of the chest (including the liver) should be performed to identify metastases. A CT/MRI examination should be done to assess local and locoregional disease. Extension into the parapharyngeal space, bone erosion, or intracranial involvement is seen only by CT/ MRI examination. Yu et al. [5] reported a 55% upstaging of T2 and a 56% upstaging of T3 patients when comparing staging done by CT scans versus plain x-rays. MRI is superior to CT in detecting infiltration along the pharyngobasilar fascia and retropharyngeal lymph nodes. CT scans are better to detect early bony invasion. CT and MRI have a low sensitivity (45% and 56% respectively) in evaluating residual disease after treatment; either could be used [6].
CT has long been used for staging NPC,especially for the detection of skull base tumor involvement with lytic or sclerotic lesions [6, 7], but it has now largely been replaced by MRI for primary and nodal staging. However, CT is still used for radiotherapy planning and, in some centers, is used together with PET using 18F-FDG. PET/CT has been shown to be of value in NPC staging, where the main advantage is for the detection of distant metastasis [8]. It is also used for monitoring patients after therapy and detecting NPC recurrence.
NPC has a strong tendency for systemic metastases to the bone, chest, and/or liver, with up to 5% of patients having distant metastasis at presentation. M1 tumor staging determines stage IVC disease.7,27 Up to 30% of patients will have distant recurrence after radiation therapy.15,28 National Comprehensive Cancer Network (NCCN) practice guidelines recommend positron emission tomography– computed tomography (PET-CT) to evaluate for distant metastases when N2 or N3 disease is present.
Overview
On the head and neck CT scan, nasopharyngeal carcinoma is characterized by presence of soft tissue masses most commonly centered at the lateral nasopharyngeal recess (fossa of Rosenmüller).
CT scan
On the head and neck CT scan, nasopharyngeal carcinoma is characterized by soft tissue masses most commonly centred at the lateral nasopharyngeal recess (fossa of Rosenmüller). Larger tumours may be seen extending into any direction, eroding:
- Base of skull
On CT scan, assessment of cervical lymph nodes is essential due to the high rate of nodal involvement at the time of diagnosis.[1]
CT has long been used for staging NPC,especially for the detection of skull base tumor involvement with lytic or sclerotic lesions [6, 7], but it has now largely been replaced by MRI for primary and nodal staging. However, CT is still used for radiotherapy planning and, in some centers, is used together with PET using 18F-FDG. PET/CT has been shown to be of value in NPC staging, where the main advantage is for the detection of distant metastasis [8]. It is also used for monitoring patients after therapy and detecting NPC recurrence.