Does staging computered tomography change management in thick malignant melanoma?

Patients with cutaneous head and neck melanoma, particularly elderly with more advanced primary tumors, seem to benefit from initial CT staging before considering a sentinel lymph node biopsy

Background: The role of CT scanning at the time of diagnosis for patients with primary cutaneous head and neck melanoma (cHNM) clinically asymptomatic for metastatic disease remains unclear.Aim: To determine the positive yield of initial CT scanning before considering sentinel lymph node biopsy (SLNB) staging.Materials and methods: A retrospective review was performed on 170 consecutive patients with cHNM referred to a tertiary head and neck academic center for SLNBs from 2014 through 2018.Results: Initial CTs identified occult melanoma metastases in 7.1% and other advanced malignancies in 4.7%. The overall CT yield for patients >65 years (n = 115) was 13.9%, and 5.5% for patients <65 (only occult melanoma metastases). The SLNB yield did not differ between older (11.5%) and younger patients (10.2%). Patients with more advanced primary tumors were upstaged more often by both staging procedures. Multivariate analysis indicated a true-positive CT finding as the strongest prognostic factor for OS (p<.001).Conclusions and significance: The CT yield was >11% and higher for older than for younger patients. The findings suggest that CT imaging may be considered before SLNB staging, potentially identifying metastatic melanoma disease as well as other occult malignancies, enabling especially older patients to bypass the SLNB procedure.

Ultrasound, CT, MRI, or PET-CT for staging and re-staging of adults with cutaneous melanoma

BACKGROUND

Melanoma is one of the most aggressive forms of skin cancer, with the potential to metastasise to other parts of the body via the lymphatic system and the bloodstream. Melanoma accounts for a small percentage of skin cancer cases but is responsible for the majority of skin cancer deaths. Various imaging tests can be used with the aim of detecting metastatic spread of disease following a primary diagnosis of melanoma (primary staging) or on clinical suspicion of disease recurrence (re-staging). Accurate staging is crucial to ensuring that patients are directed to the most appropriate and effective treatment at different points on the clinical pathway. Establishing the comparative accuracy of ultrasound, computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET)-CT imaging for detection of nodal or distant metastases, or both, is critical to understanding if, how, and where on the pathway these tests might be used.

OBJECTIVES

Primary objectivesWe estimated accuracy separately according to the point in the clinical pathway at which imaging tests were used. Our objectives were:• to determine the diagnostic accuracy of ultrasound or PET-CT for detection of nodal metastases before sentinel lymph node biopsy in adults with confirmed cutaneous invasive melanoma; and• to determine the diagnostic accuracy of ultrasound, CT, MRI, or PET-CT for whole body imaging in adults with cutaneous invasive melanoma:○ for detection of any metastasis in adults with a primary diagnosis of melanoma (i.e. primary staging at presentation); and○ for detection of any metastasis in adults undergoing staging of recurrence of melanoma (i.e. re-staging prompted by findings on routine follow-up).We undertook separate analyses according to whether accuracy data were reported per patient or per lesion.Secondary objectivesWe sought to determine the diagnostic accuracy of ultrasound, CT, MRI, or PET-CT for whole body imaging (detection of any metastasis) in mixed or not clearly described populations of adults with cutaneous invasive melanoma.For study participants undergoing primary staging or re-staging (for possible recurrence), and for mixed or unclear populations, our objectives were:• to determine the diagnostic accuracy of ultrasound, CT, MRI, or PET-CT for detection of nodal metastases;• to determine the diagnostic accuracy of ultrasound, CT, MRI, or PET-CT for detection of distant metastases; and• to determine the diagnostic accuracy of ultrasound, CT, MRI, or PET-CT for detection of distant metastases according to metastatic site.

SEARCH METHODS

We undertook a comprehensive search of the following databases from inception up to August 2016: Cochrane Central Register of Controlled Trials; MEDLINE; Embase; CINAHL; CPCI; Zetoc; Science Citation Index; US National Institutes of Health Ongoing Trials Register; NIHR Clinical Research Network Portfolio Database; and the World Health Organization International Clinical Trials Registry Platform. We studied reference lists as well as published systematic review articles.

SELECTION CRITERIA

We included studies of any design that evaluated ultrasound (with or without the use of fine needle aspiration cytology (FNAC)), CT, MRI, or PET-CT for staging of cutaneous melanoma in adults, compared with a reference standard of histological confirmation or imaging with clinical follow-up of at least three months' duration. We excluded studies reporting multiple applications of the same test in more than 10% of study participants.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted all data using a standardised data extraction and quality assessment form (based on the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2)). We estimated accuracy using the bivariate hierarchical method to produce summary sensitivities and specificities with 95% confidence and prediction regions. We undertook analysis of studies allowing direct and indirect comparison between tests. We examined heterogeneity between studies by visually inspecting the forest plots of sensitivity and specificity and summary receiver operating characteristic (ROC) plots. Numbers of identified studies were insufficient to allow formal investigation of potential sources of heterogeneity.

MAIN RESULTS

We included a total of 39 publications reporting on 5204 study participants; 34 studies reporting data per patient included 4980 study participants with 1265 cases of metastatic disease, and seven studies reporting data per lesion included 417 study participants with 1846 potentially metastatic lesions, 1061 of which were confirmed metastases. The risk of bias was low or unclear for all domains apart from participant flow. Concerns regarding applicability of the evidence were high or unclear for almost all domains. Participant selection from mixed or not clearly defined populations and poorly described application and interpretation of index tests were particularly problematic.The accuracy of imaging for detection of regional nodal metastases before sentinel lymph node biopsy (SLNB) was evaluated in 18 studies. In 11 studies (2614 participants; 542 cases), the summary sensitivity of ultrasound alone was 35.4% (95% confidence interval (CI) 17.0% to 59.4%) and specificity was 93.9% (95% CI 86.1% to 97.5%). Combining pre-SLNB ultrasound with FNAC revealed summary sensitivity of 18.0% (95% CI 3.58% to 56.5%) and specificity of 99.8% (95% CI 99.1% to 99.9%) (1164 participants; 259 cases). Four studies demonstrated lower sensitivity (10.2%, 95% CI 4.31% to 22.3%) and specificity (96.5%,95% CI 87.1% to 99.1%) for PET-CT before SLNB (170 participants, 49 cases). When these data are translated to a hypothetical cohort of 1000 people eligible for SLNB, 237 of whom have nodal metastases (median prevalence), the combination of ultrasound with FNAC potentially allows 43 people with nodal metastases to be triaged directly to adjuvant therapy rather than having SLNB first, at a cost of two people with false positive results (who are incorrectly managed). Those with a false negative ultrasound will be identified on subsequent SLNB.Limited test accuracy data were available for whole body imaging via PET-CT for primary staging or re-staging for disease recurrence, and none evaluated MRI. Twenty-four studies evaluated whole body imaging. Six of these studies explored primary staging following a confirmed diagnosis of melanoma (492 participants), three evaluated re-staging of disease following some clinical indication of recurrence (589 participants), and 15 included mixed or not clearly described population groups comprising participants at a number of different points on the clinical pathway and at varying stages of disease (1265 participants). Results for whole body imaging could not be translated to a hypothetical cohort of people due to paucity of data.Most of the studies (6/9) of primary disease or re-staging of disease considered PET-CT, two in comparison to CT alone, and three studies examined the use of ultrasound. No eligible evaluations of MRI in these groups were identified. All studies used histological reference standards combined with follow-up, and two included FNAC for some participants. Observed accuracy for detection of any metastases for PET-CT was higher for re-staging of disease (summary sensitivity from two studies: 92.6%, 95% CI 85.3% to 96.4%; specificity: 89.7%, 95% CI 78.8% to 95.3%; 153 participants; 95 cases) compared to primary staging (sensitivities from individual studies ranged from 30% to 47% and specificities from 73% to 88%), and was more sensitive than CT alone in both population groups, but participant numbers were very small.No conclusions can be drawn regarding routine imaging of the brain via MRI or CT.

AUTHORS' CONCLUSIONS

Review authors found a disappointing lack of evidence on the accuracy of imaging in people with a diagnosis of melanoma at different points on the clinical pathway. Studies were small and often reported data according to the number of lesions rather than the number of study participants. Imaging with ultrasound combined with FNAC before SLNB may identify around one-fifth of those with nodal disease, but confidence intervals are wide and further work is needed to establish cost-effectiveness. Much of the evidence for whole body imaging for primary staging or re-staging of disease is focused on PET-CT, and comparative data with CT or MRI are lacking. Future studies should go beyond diagnostic accuracy and consider the effects of different imaging tests on disease management. The increasing availability of adjuvant therapies for people with melanoma at high risk of disease spread at presentation will have a considerable impact on imaging services, yet evidence for the relative diagnostic accuracy of available tests is limited.

Benefits of initial CT staging before sentinel lymph node biopsy in patients with head and neck cutaneous melanoma

BACKGROUND

The value of CT at the time of diagnosis for patients with cutaneous head and neck melanoma clinically asymptomatic for metastatic disease is unclear.

METHODS

A retrospective medical chart review was performed on 198 consecutive patients identified with primary T1b-T4b head and neck melanoma clinically asymptomatic for metastatic disease referred for sentinel lymph node biopsy procedures between 2004 and 2014.

RESULTS

Initial CTs identified clinically occult melanoma metastases in 8.1% and advanced second primary tumors in 3.5% of patients. CT findings were false-negative in 1% and false-positive in 6% of patients. Overall survival (OS) for patients with true-positive CT findings was lower than for the other patients (P < .001).

CONCLUSION

CT imaging when staging patients with head and neck melanoma seems to identify more metastases than has been reported for melanoma at other sites. Preoperative CTs decreased the number of sentinel lymph node biopsy (SLNBs), thus avoiding the stress and cost of this surgical procedure in 12% of patients.

Melanoma patient imaging in the era of effective systemic therapies

Imaging plays a critical role in the current multi-disciplinary management of patients with melanoma. It is used for primary disease staging, surgical planning, and surveillance in high-risk patients, and for monitoring the effects of systemic or loco-regional therapies. Several different imaging modalities have been utilised in the past. Contemporary imaging practises vary geographically depending on clinical guidelines, physician preferences, availability and cost. Targeted therapies and immunotherapies have revolutionised the treatment of patients with metastatic melanoma over the last few years. With this have come new patterns of disease that were not observed after conventional therapies, and new criteria to assess therapeutic responses. In this article we review the role of imaging for patients with melanoma in the era of effective systemic therapies and discuss likely future developments.

Comparative accuracy of intravenous contrast-enhanced CT versus noncontrast CT plus intravenous contrast-enhanced CT in the detection and characterization of patients with hypervascular liver metastases: a critically appraised topic

RATIONAL AND OBJECTIVES

To evaluate whether addition of nonenhanced computed tomography (NECT) to intravenous contrast-enhanced (CE) abdominal CT improves detection or characterization of hypervascular liver masses. Patients were referred for initial staging or follow-up with known breast, melanoma, neuroendocrine, or thyroid cancer.

MATERIAL AND METHODS

The literature was searched using the patient, intervention, comparison, and outcome (PICO) method. Retrieved articles were critically appraised and assigned a level of evidence based on the Oxford University Centre for Evidence-based Medicine hierarchy of validity for diagnostic studies.

RESULTS

One thousand one hundred studies were reviewed; only 11 studies matched the PICO of our study and were appraised. Most of the appraised articles were published in the 1990s using older technology and contrast delivery. The retrieved diagnostic performance for characterization of liver metastases showed sensitivity/specificity of 97%/76% for NECT, 97%/75% for arterial CT, and 98%/76% for portal venous phase CT in patients with breast cancer; sensitivity of 96% (arterial and portal CT) versus 100% (NECT, arterial and portal CT) in patients with melanoma; and sensitivity of 43% (portal CT) versus 17% (NECT) in patients with neuroendocrine tumor. No primary study was found for performance of different CT protocols in patients with thyroid cancer. Available evidence showed radiologists reported more conspicuous liver masses on CECT compared to NECT in patients with breast or neuroendocrine cancer.

CONCLUSIONS

Based on existing evidence, NECT only adds a small incremental value to CECT for detection/characterization of hypervascular liver metastases. Addition of NECT increases patient's exposure to radiation and the number of images available for interpretation.