Demographics and prediction accuracy of upper extremity tumors: A 10-year retrospective study



    Table of Contents ORIGINAL ARTICLE Year : 2022  |  Volume : 30  |  Issue : 1  |  Page : 11-16

Demographics and prediction accuracy of upper extremity tumors: A 10-year retrospective study

Galip Gencay Ustun1, Murat Kara1, Fethiye Damla Menku Ozdemir1, Hakan Uzun1, Özay Gököz2, Ali Emre Aksu1
1 Department of Plastic Reconstructive and Aesthetic Surgery, Hacettepe University, Ankara, Turkey
2 Department of Pathology, Faculty of Medicine, Hacettepe University, Ankara, Turkey

Date of Submission25-Jan-2021Date of Acceptance12-Sep-2021Date of Web Publication25-Dec-2021

Correspondence Address:
Dr. Ali Emre Aksu
Hacettepe Universitesi Hastaneleri, Plastik Cerrahi AD Sekreterligi, Ankara 06100
Turkey
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/tjps.tjps_7_21

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Background: Upper extremity tumors (UETs) and their treatment may impair hand functions. Successful prediction of the histopathological examination before surgery will speed up the treatment process. The aim of this study is to determine the frequency and prediction accuracy of tumors encountered in the upper extremity. Patients and Methods: Records of patients operated for UETs between January 2010 and December 2019 were reviewed. Patient gender, initial complaint, the anatomic region of the tumor, comorbidities predisposing to malignancy, method of biopsy, preliminary diagnosis and predicted malignancy status after initial examination, definitive histopathological diagnosis, and malignancy status were extracted retrospectively. Prediction accuracy rates were calculated for each tumor group. Chi-square analysis was used for comparative analysis of prediction accuracy rates between cutaneous pigmented versus soft-tissue lesions and patients with/without a predisposition to malignancy. Results: The study included 416 pathological specimens from 290 patients. The most common tumors of the upper extremity were lipoma (20%), ganglion cyst (10.1%), and epidermoid cyst (5.8%). After pathological evaluation, 23 specimens were diagnosed as malignant (5.5%) and 32 specimens as premalignant (7.7%). The prediction of malignancy status was accurate in 390 specimens (93.7%). Soft-tissue sarcomas (67.7%) and vascular lesions (58.1%) have the lowest accuracy rates among all tumors. Conclusion: Definitive diagnosis and malignity status can be predicted after the initial examination in the majority of the cases. However, imaging studies or incisional biopsies are needed for soft-tissue sarcomas, vascular tumors, or tumors of patients with a predisposing condition to malignancy.

Keywords: Pigmented lesion, prediction accuracy, sarcoma, tumor, upper extremity


How to cite this article:
Ustun GG, Kara M, Menku Ozdemir FD, Uzun H, Gököz &, Aksu AE. Demographics and prediction accuracy of upper extremity tumors: A 10-year retrospective study. Turk J Plast Surg 2022;30:11-6
How to cite this URL:
Ustun GG, Kara M, Menku Ozdemir FD, Uzun H, Gököz &, Aksu AE. Demographics and prediction accuracy of upper extremity tumors: A 10-year retrospective study. Turk J Plast Surg [serial online] 2022 [cited 2021 Dec 25];30:11-6. Available from: http://www.turkjplastsurg.org/text.asp?2022/30/1/11/333754   Introduction Top

The hand, described as “window to the brain” by Immanuel Kant,[1] is a highly functional unit of the human body. Upper extremity tumors (UETs) may worsen hand functions. Treatment of hand tumors may be complicated, as the hand contains bones, muscles, nerves, and vessels in close proximity.

UETs show a large degree of benign behavior. The most common benign tumors encountered during practice are warts, pigmented lesions, ganglion cysts, giant cell tumors of the tendon sheath, and vascular tumors.[2],[3],[4],[5] Warts can be treated using cryotherapy, electrocoagulation, laser therapy, and topical drug applications, so they are rarely encountered by the hand surgeon.[6] With other benign tumors, treatment is excision with clear surgical margins. Yet, 1%–2% of primary hand tumors are malignant and these tumors require broader margins and further work-up.[7]

There is a relative consensus on the most common malignant skin tumor of the upper extremity as squamous cell carcinoma (SCC).[8],[9] Frequencies of the sarcomas differ from each other in different case series, as these tumors are extremely rare. Undifferentiated pleomorphic sarcoma (formerly known as malignan fibrous histiocytoma), liposarcoma, and fibrosarcoma are the most common soft-tissue sarcomas diagnosed in the upper extremity.[10],[11]

Although malignant tumors are rarely seen in the upper extremity, the rate of malignancy is higher if the patient has certain conditions. Having inherited diseases such as neurofibromatosis type I (NF-I), Gorlin syndrome, familial atypical multiple mole melanoma, or xeroderma pigmentosum (XP) increases the risk for malignancy.[12] In addition, patients with another primary malignancy may also have a metastasis to the upper extremity.[13]

“Diagnostic accuracy” is a rather novel term, which refers to the accurate prediction of the histopathological diagnosis before tumor excision and histopathological examination. Accurate prediction speeds up the treatment process and strengthens the physician's hand during the planning of the treatment.[14]

Inadequate treatment of an existing malignant tumor is a feared complication. However, unnecessary overtreatment of a benign tumor is also a condition that should be avoided. “Diagnostic accuracy” concept, which was initially defined on cases of malignant melanoma, also started to be applied to malignant nonmelanomatous skin tumors.[15] Patient history and physical examination are tools that can give valuable insight to the physician for accurate prediction, and cost-effectiveness is a major advantage for their use. The most commonly known physical examination tool is Asymmetry–Border irregularity–Color variegation–Diameter–Elevation or Evolution (ABCDE) for malignant melanoma. In addition to these traditional tools, new devices or imaging techniques that claim to increase diagnostic accuracy are also being proposed, with developing technology. Tools such as dermoscopy, dermatoscopy, high-frequency ultrasound, positron emission tomography (PET), and electrical impedance have also been presented.[16] Each of these tools claims to predict histopathological diagnosis or, at least malignancy status, on a level. Lately, a computer software using artificial intelligence to learn and apply diagnostic criteria to skin tumors with substantial accuracy has also been presented.[17] However, acquisition and use of these instruments require financial resources and qualified personnel that the facility may be lacking.

To our knowledge, the prediction accuracy of UETs has not been studied before. Physical examination and history taking are basic skills of medicine. The aim of the present study is to analyze (1) the frequencies of UETs on a relatively large patient population, (2) the prediction accuracy of UETs with basic physical examination and history-taking tools, and (3) the factors affecting the prediction accuracy.

  Patients and Methods Top

Following the approval of the Local Ethics Committee (GO: 20/499), the records of patients who were operated for UETs between January 2010 and December 2019 were retrospectively reviewed. Patient gender, initial complaint, the anatomic region of the tumor, comorbidities predisposing to malignancy, method of biopsy, preliminary diagnosis and predicted malignancy status after initial examination, definitive histopathological diagnosis, and malignancy status were reviewed. Prediction accuracy rates were calculated for each tumor group.

The concept of preliminary diagnosis used in the study was determined as the preliminary diagnosis written in the patient file before any further examination (e.g., imaging studies or incisional biopsies) after the first patient interview. Each of the surgeons who made this assessment was a plastic surgeon with at least 5 years of clinical experience.

Criteria used for prediction of the diagnosis were as follows:

Duration of complaints (e.g., mass and pain)Location and size of the tumorPresence of pain, pulsation (or bruit), bleeding, paresthesia, or Tinel's signFixation to peripheral structures and presence of ill-defined bordersABCDE criteria (for pigmented lesions)History of malignancy or predisposition to malignancy.

Descriptive statistics are used for the interpretation of frequencies. Chi-square analysis was used for comparative analysis of prediction accuracy rates between pigmented/mass lesions and patients with/without a predisposition to malignancy.

Data were analyzed using IBM SPSS Statistics for Windows v. 20.0 (IBM Corp, Armonk, NY, USA). The level of statistical significance was set at P < 0.05.

  Results Top

The study included 416 histopathological specimens from 290 patients. Fifty-one percent (51%) of these patients were female (n = 148) and 49% were male (n = 142). The mean age of the patients was 39.59 ± 18.98 years, and the median age was 35.5 years. Thirteen of 290 patients (4.5%) had comorbidities predisposing to malignancy, such as NF-I and XP. Of 416 specimens, 281 (67.5%) presented with a pigmented lesion and 135 (32.5%) presented with a subcutaneous mass. Fifty-two percent of these tumors were taken from the right extremity (n = 215), whereas 48% of them were taken from the left (n = 201). The anatomical regions of the tumors are listed in [Table 1]. The most common location was the wrist/hand region (29.3%), followed by the arm (23.3%) and fingers (23.3%).

At initial evaluation, 77 of 416 UETs (18.5%) were predicted to be malignant/premalignant. Excisional biopsy was the method of treatment chosen in the majority of the patients (98.1%). The histopathological diagnosis of the study group is listed in [Table 2]. The most common tumors of the upper extremity were lipoma (20%), ganglion cyst (10.1%), and epidermoid cyst (5.8%). After pathological evaluation, 23 specimens were diagnosed as malignant (5.5%) and 32 specimens were diagnosed as premalignant (7.7%).

The prediction of malignancy status was accurate in 390 specimens (93.7%). Twenty-five specimens (6.6%) predicted as premalignant/malignant were reported as benign tumors, whereas one specimen predicted to be benign was found out to be malignant (malignant melanoma) (0.2%).

Prediction accuracy of the preliminary diagnosis was highest with ganglion cysts (100%), neuromas (100%), giant cell tumors of the tendon sheath (100%), and pyogenic granulomas (90.9%). Soft-tissue sarcomas (67.7%) and vascular lesions (arteriovenous malformations [AVMs] and hemangiomas, 58.1%) had the lowest prediction accuracy rates. Vascular lesions presented as subcutaneous masses could be predicted accurately in 38% of the cases.

Malignancy status of the pigmented lesions could be predicted with less accuracy than mass lesions [P < 0.001, [Table 3]]. There was a statistically significant difference between pigmented and mass lesions in terms of accurate prediction of the final diagnosis too (P < 0.001) [Table 4]. Specimens taken from patients who had comorbidities predisposing to malignancy were found to be predicted with less accuracy (P < 0.001).

Table 3: Comparison of prediction accuracy of malignity in patients who presented with subcutaneous masses and pigmented lesions

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Table 4: Comparison of prediction accuracy of patients who presented with subcutaneous masses and pigmented lesions

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  Discussion Top

Most of the daily practice of hand surgery is repair/reconstruction after posttraumatic injuries and congenital anomalies, but tumors of this region possess specific challenges. From shoulder to hand, subcutaneous adipose tissue decreases and anatomical structures converge. In the presence of a tumor, benign or malignant, this convergence facilitates damage to these structures. In addition, the probability of damage to adjacent structures (e.g., nerves) due to excision increases.

The most important variables for preserving function and protecting the surrounding structures during surgery are tumor size and malignancy.[18],[19],[20] For malignant tumors, in addition to the impact caused by invasion, the need for larger clear margins during excision also increases the possibility of functional loss after surgery. Fortunately, malignant tumors of the upper extremity are rarely seen. While the rate of malignant tumors is 6.7% in the study group, there were only three cases of soft-tissue sarcoma (0.7%). This rate, which is even <1%, has been reported to be similar in previous studies.[21],[22] Murray also emphasized the rarity of these tumors, as a hand surgeon would encounter an undiagnosed soft-tissue sarcoma once or twice throughout his/her life.[10] Even though pigmented malignant tumors are relatively more common, only two of the malignant tumors diagnosed in our patient series were observed to be Stage 3 (2/21, 9.5%) and none of the patients were Stage 4. The authors think patients have an advantage of early detection as the entire area from the arm level to the hand is in the patient's visual field. In contrast to general data, the most common tumor was malignant melanoma in the study group, albeit with a slight difference (followed by SCC). National data on this subject have not been published yet, and melanocyte-derived malignancies may be more common in the studied population. The relatively young population of the study group (median age = 35.5 years) may have led to lower detection of advanced age malignancies such as SCC. Remarkable data are that no patient was diagnosed with basal cell carcinoma (BCC) in the presented patient series. It can be hypothesized that cultural dressing habits prevent sun exposure, but it is clear that these data need to be verified by other studies.

When the most frequently diagnosed tumors in the study group are analyzed, it is seen that lipomas are the leading group. In the past, despite their frequent existence in the human body, it was assumed that lipomas are rarely seen in the upper extremity, especially in the hand.[23] However, subsequent studies have reported lipomas in many different localizations of the upper limb, including the subungual region and the Guyon's canal.[24],[25] Lipomas can rarely be symptomatic for reasons such as peripheral nerve compression, and are otherwise asymptomatic.[26] Lipomas in hand are rarely seen in the present study, as most were observed in the forearm and proximal to this level. Considering that the subcutaneous adipose tissue thickens proximally, these tumors are more likely to be diagnosed toward the shoulder region. Treatment is an excisional biopsy, but preservation of digital bundles, especially with lesion presenting in hand, may possess a challenge during excision.

Vascular lesions such as AVMs and hemangiomas may present as subcutaneous masses (41% in this patient series) rather than pigmented lesions, especially if they are located deep in tissue planes. Patient history and examination may help to differentiate hemangiomas from AVMs. However, without cutaneous manifestations, the onset of the lesion may not be fully clarified. Even with this information, because of the noninvoluting congenital hemangioma phenomenon, a definitive diagnosis can only be made after the histopathological examination. If presented as subcutaneous masses, the prediction accuracy of vascular tumors is found to be only 38.4% (5 of 13 cases), which is fairly low. Although pain is a common complaint in these patients, soft tissue sarcomas often present with the complaint of pain, too. Soft-tissue sarcomas also had a relatively low predictive accuracy (67.7%). The authors believe preoperative magnetic resonance imaging (MRI) can be recommended to patient's presenting with pain, a tumor settled deep in tissue planes, and have an inconclusive physical examination, according to our findings.

“Diagnostic accuracy” is a rather novel term. It is commonly used for pigmented lesions or skin cancers in the literature. Numerous tools have been offered to increase the prediction accuracy of skin cancers. The tool with the largest clinical use is dermoscopy, which allows the lesion to be examined under ×10–100 magnification. However, its use is limited to pigmented lesions. It has no use with subcutaneous masses. Despite widely used with pigmented lesions, consensus regarding diagnostic criteria for dermoscopy is lacking and it is not incorporated in plastic surgeon's daily practice yet. Tools such as fluorescence imaging, Doppler sonography, confocal microscopy, and spectroscopy are still used experimentally.[16] Computerized tomography (CT), PET-CT, and MRI have different uses in daily practice, and plastic surgeon has an advantage of familiarity to these devices. It has been shown that PET-CT has 95% sensitivity and 100% specificity in detecting head-and-neck nonmelanomatous skin cancers.[27] MRI has the advantage of giving detailed tumor localization and showing extent into healthy tissues. Detailed imaging gives access to information such as perineural invasion and an estimation of prognosis can be done.[28] It is clear that these imaging techniques are not sufficient to provide definitive diagnosis, although they seem to be beneficial. Our findings show that physical examination and history taking provide sufficient insight during the prediction of the majority of the UETs, and these patients may be treated with excisional biopsy after the initial examination without further work-up. However, vascular tumors without cutaneous manifestations and soft-tissue sarcomas are exceptional in this case. We recommend the use of MRI with deep subcutaneous masses of upper extremity, and patients presented with pain in upper extremity without a pattern of compression neuropathy. For suspected vascular lesions of the upper extremity, MR angiogram gives detailed information.

The most important advantage of the preliminary determination of the malignancy potential of the masses is that the patient can be informed more accurately before any work-up/operation. In addition, it will be possible to make an early appointment for the procedures for tumors with a high probability of malignancy and to start the treatment as soon as possible. Some masses show stereotypical manifestations which are useful in predicting the malignancy potential. Ganglion cysts involve periscaphoideal joints and they are accompanied by pain, while giant cell tumors of the tendon sheath present as painless botryoid-like masses distal to Metacarpophalangeal (MCP) joint. These stereotypical features played a role in the predictability of these tumors as 100%. Nevertheless, it becomes difficult to predict the case in masses that do not have skin manifestations, are deeply located, and only have insignificant findings such as dull pain or discomfort. Our recommendation is to start the diagnosis process quickly in such masses and to make an early surgery appointment.

Patients with XP have decreased ability to repair DNA damage caused by ultraviolet (UV) radiation. Repetitive DNA damage may cause skin cancers.[29] Risk is greater for BCC and SCCs (>10000 fold) than malignant melanoma (>2000 fold).[30] NF-I is an autosomal dominantly inherited disorder presenting with skinfold freckling, cafe-au-lait macules, and neurofibromas.[31] NF-I patients also have a predisposition to malignancy. The estimated lifetime cancer risk is 59.6% with patients with NF-I.[32] Therefore, close monitoring of the skin lesions and the subcutaneous masses is important for these patients. However, our analysis shows lesions taken from patients with a predisposition to malignancy had lower predictive accuracy rates than otherwise healthy patients (77% vs. 96%, P < 0.001). When the cases are evaluated on a case basis, it was seen that this difference was due to higher false-positive cases in the predisposed patient group, so overtreatment seems to be the issue. XP cases usually need repetitive excisions for refractory lesions on their face due to UV damage. Overtreatment may cause a need for skin grafting due to the inability to primary repair of the resulting defect. Likewise, wide excision of benign neurofibromas increases the risk for hematoma, as these are highly vascular tumors.[33] With dropping accuracy rates in patients with a predisposition to malignancy, we think incisional biopsies at the beginning of the process may help to shape definitive treatment.

  Conclusion Top

Our study shows definitive histopathological diagnosis and at least the malignity status of the majority of the UETs can be predicted with accuracy with physical examination and patient history. However, accuracy rates drop with vascular tumors without cutaneous manifestations, tumors from patients with predisposition to malignancy, and tumors localized to deep compartments suggesting soft-tissue sarcomas. We suggest the use of MR angiogram with suspected vascular tumors. This tool not only helps to diagnose, but also suggests whether it is safe to use sclerotherapy or surgery for treatment. With patients who have a predisposition to certain malignant conditions, we suggest starting treatment with incisional biopsies if the lesion is not eligible for excisional biopsy. Deep subcutaneous masses of the upper extremity need to be visualized using MRI, especially if the patient's history suggests a soft-tissue sarcoma.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

 

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  [Table 1], [Table 2], [Table 3], [Table 4]
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