Low back pain as main symptom in Low-grade Appendiceal Mucinous Neoplasm (LAMN): A case report

ABSTRACT

Background

Low back pain is the leading cause of disability worldwide. It is also the main cause of the limitation of activities and absence from work in much of the world and a cause of great economic burden. The greatest percentage of low back pain is classified as nonspecific (i.e. not attributable to a defined pathology), while the others may concern specific pathologies of the lumbar region or suggest pathologies of non-musculoskeletal origin. Consequently, evaluating any signs and symptoms mimicking musculoskeletal conditions is crucial.

Case Description

This case report describes a 64-year-old female patient who first presented to the physiotherapist with two weeks of low back pain, complaining of a different clinical presentation than the previous episodes. The patient’s pain started spontaneously and was located in the lumbar region over a diffuse area. Symptoms were constant throughout the day and did not change with movement. Based on the examination findings, the physiotherapist decided to make an urgent referral to the patient’s General Practitioner.

Outcomes

Following ultrasound examination and Computed Tomography scan, an 8.5 cm mass was confirmed in the abdominal region. It was surgically removed, and a histological diagnosis of Low-grade Appendiceal Mucinous Neoplasm (LAMN) was made.

Conclusion

The physiotherapist’s evaluation and decision-making process was fundamental in the patient’s referral due to suspected pathology not within the scope of practice. This revealed a rare condition, which, according to the existing literature, is usually diagnosed in the event of collateral imaging findings or upon presentation of complex and/or emergency clinical pictures.

KEYWORDS:

• Specific back pain
• appendiceal mucinous neoplasm
• evaluation
• referral
• case report

Background

Low Back Pain (LBP) is the leading cause of disability worldwide, the main cause of limitation of activities and absence from work, and represents an economic burden (GBD 2015Disease and Injury Incidence and Prevalence Collaborators, 2016; Hartvigsen et al., 2018; Hoy, Brooks, Blyth, and Buchbinder, 2010; Maselli et al., 2020). The lifetime incidence of LBP is 58–84%^, whereas its prevalence in industrialized countries ranges from 12% to 35% and rises with increasing age, reaching a peak between 60 to 65 years (Loney and Stratford, 1999; Parsons, Ingram, Clarke-Cornwell, and Symmons, 2011). As a result, it must be considered an urgent global public health concern in today’s world. LBP is considered “a symptom” and not “a pathology” which may arise from many different causes, known and unknown (Bardin, King, and Maher, 2017). It’s not always possible to identify its specific cause; for this reason, most cases of LBP are defined as “non-specific” (Hartvigsen et al., 2018). This definition includes all cases without underlying specific serious spinal pathology, representing approximately 90–95% of cases (Henschke et al., 2009; Maher, Underwood, and Buchbinder, 2017; Vlaeyen et al., 2018). For the remaining 5–10% of cases of LBP, there is a specific underlying pathology such as a vertebral fracture, a tumor, cauda equina syndrome, infection, or disease of the pelvic or vascular organs (Machado, Rogan, and Maher, 2018; Maselli, Rossettini, Viceconti, and Testa, 2019). In such cases, it may prove effective to follow a pathoanatomic model-based approach aimed at discovering the origin of the symptoms (Finucane et al., 2020). It is strongly recommended that the evaluation of patients presenting directly for the first time with LBP should include screening to identify potential cases of serious pathology (Andreoletti et al., 2022; de Jager and Ahern, 2004; Maselli et al., 2022, 2022; Piano et al., 2017). Two systematic reviews on the screening for tumors and fractures showed considerable uncertainty surrounding the prevalence of these serious pathologies in patients with LBP, demonstrating a prevalence of cancer between 0.1% to 3.5% and a prevalence of vertebral fractures between 3% to 29% (Henschke, Maher, and Refshauge, 2007, 2008).

Mucinous tumor of the appendix is a rare pathology, with less than 0.5% prevalence (Italian Association of Oncology Medicine, 2023). Clinical presentation usually occurs in the sixth decade of life, more commonly among women, and can clinically mimic acute appendicitis. The incidental diagnosis is estimated at 43% of patients (Villa et al., 2021). It can manifest with systemic symptoms, abdominal pain, and palpable masses (Li, Zhou, Dong, and Yang, 2018; Pantiora et al., 2018). A single case in the literature noted abdominal pain and failure to improve with conservative treatment (Deyo and Diehl, 1988). Low-Grade Appendiceal Mucinous Neoplasm (LAMN) is a risk factor for Pseudomyxoma peritonei (PMP), which is a large collection of intra-abdominal mucus (Bevan, Mohamed, and Moran, 2010; Hegg et al., 2020; Koç et al., 2020). An early surgical approach reduces the risk of this complication (McDonald et al., 2012).

This case report aimed to describe the evaluative and decision-making process in the case of a patient with LAMN presenting directly to the physiotherapist with LBP.

Case description

History

This case report has been prepared following the CARE case report guidelines (Riley et al., 2017). A detailed medical history is shown in the timeline (Figure 1).

Figure 1. Timeline. Medical history timeline prior to the physiotherapy consultation.

Abbreviations: LBP = Low Back Pain; GP = General Practitioner; US = Ultrasound; CT = Computed Tomography; ECG = electrocardiogram; LAMN = Low-Grade Appendiceal Mucinous Neoplasm.

A 64-year-old female retired high school teacher consulted the physiotherapist for LBP. She chose to present directly to the physiotherapist because this same healthcare professional had already assisted her with conservative treatment for two previous musculoskeletal disorders. The patient had LBP for two weeks, and this presentation was different from her previous episodes of LBP. This was the main reason for her decision to contact the physiotherapist directly. In reviewing the patient’s past medical history, the patient presented with LBP at 16 while practicing competitive artistic gymnastics. At that time, she had given up practicing the aforementioned sport because she was worried about the fragility of her back, scared by the lumbar hernias diagnostic label. She described this as an emotionally distressing event and, even after many years, continued to be convinced of and worried about weakness in her lumbar region. She reported recurrent episodes of LBP throughout her life, which had resolved spontaneously. The patient noted 4–5/10 pain on the Numeric Pain Rating Scale (NPRS) (Farrar et al., 2001). The patient noted the pain occurred spontaneously, located in the lumbar region extending to the 12th rib to the middle gluteal region and the right flank (Figure 2). The patient could not point to the precise region, as it was a diffuse area. The pain had not radiated or referred to other areas, and the patient described it as: “tolerable and not particularly debilitating,” “not well-defined,” “a dull and deep pain” and “not particularly annoying but always there.” Alleviating and aggravating factors were investigated but not found to be present. In particular, pain symptoms were present constantly throughout the day, did not change when standing, lying down or moving, and were also present at night. The patient had not started any therapeutic strategy. During a detailed medical history, the patient reported an appendectomy at the age of 40 and gynecological management of uterine fibroids. She had been in menopause for over 10 years, did not have children and did not take any medication other than the sporadic use of non-steroidal anti-inflammatory drugs (NSAIDs) as needed. The patient also reported widespread weakness, difficulty gaining weight despite eating normally, regular bowel function, and did not report any symptoms during or after meals. The patient had been referred to her General Practitioner (GP) because of these sensations, who ordered blood tests that were negative. These tests did not reveal anything of relevance. Family medical history revealed a history of prostate cancer in her brother.

Figure 2. Body chart. The lower and lateral right side in back spine symptoms’ localization at the time of the first physiotherapy encounter.

The data collected up to that point and, in particular, the patient’s age, clinical presentation, symptom characteristics, widespread weakness and family history of cancer, led the physiotherapist to carry out a complete physical examination with a high level of concern toward discovering a pathology of non-musculoskeletal origin. Special tests were carried out in the area of interest, using topographical criteria as a guide, particularly in the right iliac fossa close to the scar. In the physical examination, upon observation and inspection, the patient presented with an extended abdomen with a scar in the right iliac fossa due to previous appendectomy surgery, as reported in the medical history. The abdomen was soft and non-tender upon superficial and deep palpation at McBurney’s point, with a negative Blumberg sign (Goodman, Heick, and Lazaro, 2018). Nevertheless, a key element did arise, namely the presence of a palpable mass of solid consistency in the right iliac fossa (Figure 3).

Figure 3. Patient’s abdomen at the first physiotherapy consultation. The solid circle indicates the McBurney’s point where the presence of a palpable mass of solid consistency did arise (dashed circle) in the right iliac fossa.

Physical therapy examination

To completely exclude the correlation between the patient’s current pain and one of the previous episodes of back pain, a musculoskeletal physical exam was executed. The patient was unable to recognize and reproduce any provocative movement. When testing active movements of the spine, it was impossible to reproduce the familiar symptom, which had been the reason for the consultation. Palpation of the lumbar muscles and passive provocation tests on the spinous processes provoked a pain of 4/10 NPRS: “different to the pain that had prompted her to contact the physiotherapist.”

Physical therapy diagnosis

Based on the previous appendectomy, the presence of a palpable mass in the abdomen, the inability to provoke the patient’s pain symptoms during the physical exam and the difference compared to previous episodes of pain, the patient’s back pain could not be traced back to the musculoskeletal system. Instead, her LBP was deemed a possible symptom of visceral origin (Gebhart and Bielefeldt, 2016). With a high level of concern based on all of these factors, the physiotherapist decided not to carry out any treatment and ordered the patient’s urgent referral to her General Practitioner (GP) with “suspected pathology outside his professional scope” (Goodman, Heick, and Lazaro, 2018). The patient was invited to complete the Italian version of the Medical Outcomes Study 36-Item Short-Form Health Survey (SF- 36) to assess the quality of life (Table 1) (Apolone and Mosconi, 1998).

Table 1. The Short Form Health Survey 36 (SF-36).*

SF-36 Questionnaire**
	Baseline	Follow-up
Physical component summary
Physical functioning	80	100
Role-physical	0	100
Bodily pain	45	100
General health	25	80
Mental component summary
Vitality	30	85
Role-emotional	0	100
Mental health	48	72
Social functioning	50	87.5

*(SF-36) is a self-administered questionnaire, completed by the patient, which aims to quantify health status and measure health-related quality of life.

**Range 0–100 (0 less quality of life, 100 better quality of life).

Outcomes

Medical diagnostic process

The GP consultation confirmed the diagnostic suspicion and on the recommendation of the GP, the patient initially underwent an abdominal ultrasound with a negative result. The patient had a pelvic ultrasound that revealed a 6 × 4 cm lesion (Figure 4(a)) and two lymph nodal formations (Figure 4(b)) of 16 mm and 9 mm in diameter. The recommendation of the physician was to have an abdominal CT with contrast, colonoscopy, and surgery.

Figure 4. (a) Ultrasound examination. The yellow arrow indicates a 6 × 4 cm lesion. (b) Ultrasound examination. Arrows indicate two lymph nodal formations of 16 mm (left) and 9 mm (right).

As instructed by the radiologist, the patient underwent a complete abdomen and chest CT scan (both with and without contrast medium – CM), which revealed a predominately hypodense formation,

retrocecal in the right iliac fossa, 8.5 × 5 cm on the axial plane, with fine solid sedimentations and parietal calcifications without significant impregnation after using the contrast medium (Figure 5). This was first assumed to be attributable to an appendiceal formation requiring surgical examination. Mesenteric and retroperitoneal adenopathy was not observed. Pelvic and inguinal adenopathy and free fluid in the abdomen were not shown.

Figure 5. CT scan before surgery. Arrows indicates the hypodense formation, retrocecal in the right iliac fossa, 8.5 × 5 cm on the axial plane, with fine solid sedimentations and parietal calcifications without significant impregnation after use of the contrast medium.

The subsequent colonoscopy did not show lesions of neoformative/infiltrative nature.

Surgical treatment

The medical team who took over the patient’s care opted for an emergency surgical treatment, scheduling the operating session 10 days after the CT scan. The surgeon operating diagnosed mucinous neoplasm of the appendix in reference to a previous appendectomy with severe adhesion syndrome and ordered a histological examination. The result of this exam defined an oval cystic formation measuring 8.5 × 5.5×4.2 cm histologically in line with the diagnosis of low-grade appendiceal mucinous neoplasm. Immediately post-surgery, the patient remained under observation for 4 days. During this time, an early mobilization approach was adopted where the patient was encouraged to sit upright and start walking again as early as the following morning (Hu, McArthur, and Yu, 2019; Svensson-Raskh et al., 2020). Upon discharge, the patient was given a post-colon resection diet to follow and information relating to self-treatment at home for the gradual recovery of functions and daily life activities (Americas Hernia Society Quality Collaborative, 2019). At the oncological evaluation, with the discharge diagnosis of low-grade appendiceal mucinous neoplasm, the patient presented as broadly asymptomatic with slight pain upon palpation of the scar area. In consideration of the histological examination, the oncologist suggested an upper and lower abdominal CT scan both with and without CM, follow-up tumor markers, namely CEA (Carcinoembryonic Antigen) and CA19–9 (Cancer Antigen 19–9), and an electrocardiogram.

Follow-up

At the three-month follow-up with the oncologist, the upper and lower abdominal CT scans did not show mesenteric and retroperitoneal adenopathy (Figure 6). Infiltrative processes indicating relapse were not observed at the site of the ileocolic anastomosis. Adenopathy of the pelvic lymph centers and free fluid in the abdomen were also not observed. Moreover, all required exams were negative.

Figure 6. CT scan at three months follow-up. No hypodense formation revealed and did not show mesenteric and retroperitoneal adenopathy.

In light of the results of the examinations carried out, the continuation follow-up was set with a recommendation of further follow-up at 4 months: it was also recommended that blood tests and tumor markers be taken, as well as complete abdominal ultrasound and chest X-ray. At her follow-up with the physiotherapist eight months post-surgery, the patient reported no longer experiencing LBP and having gradually and independently resumed her daily activities. The physiotherapist completed a physical examination of the abdomen and no swelling was reported (Figure 7). The patient completed an SF-36 again, which revealed improvements in all subscales (Table 1).

Figure 7. Patient’s abdomen at the physiotherapy follow-up at 8 months post-surgery.

Discussion

In most cases, LBP is considered a disorder without underlying specific serious pathology (Bardin, King, and Maher, 2017; Henschke et al., 2009; Maher, Underwood, and Buchbinder, 2017). The high incidence and prevalence of such a musculoskeletal condition are critical in managing patients presenting directly with lower back pain (Machado, Rogan, and Maher, 2018). The infrequency of serious pathology and the heterogeneity of the possible signs and symptoms require further investigation (Finucane et al., 2020; Maselli, Rossettini, Viceconti, and Testa, 2019).

In this case report, the evaluation and the decision-making process carried out by the physiotherapist were fundamental in his decision to refer the patient (Screening for Referral) due to suspected pathology not within his scope of competence (Hegg et al., 2020; Hu, McArthur, and Yu, 2019). This revealed a rare condition of neoplasia, usually diagnosed in the event of collateral imaging findings or upon presentation of complex and/or emergency clinical pictures (Li, Zhou, Dong, and Yang, 2018; Pantiora et al., 2018; Villa et al., 2021). The patient’s previous medical and rehabilitation history, given the concomitant presence of psychosocial factors related to LBP, as well as the musculoskeletal conditions in general, could have misled the clinician, leading him immediately toward a musculoskeletal condition (Vlaeyen et al., 2018). As a result, it was important for the physiotherapist to carry out an accurate evaluation, even if the patient has already been evaluated and assisted in the past. Differential diagnosis proceeds through the screening process, from patient’s history to systems review. While there is a lack of high-quality evidence that confers diagnostic accuracy of individual warning signs for serious pathologies (Finucane et al., 2020), to date, there are no better procedural algorithms. Therefore, the set of these alarm signals, including the age of the patient, the insidious onset, the symptoms that could not be modified by movement, the symptoms that were difficult to localize, the sensation of difference compared to previous painful experiences, the absence of attenuating and aggravating factors but, above all, the detection of a palpable abdominal mass, allowed the therapist to identify a high patient risk profile, with an important level of concern (Finucane et al., 2020). This way of proceeding allowed the therapist, through appropriate clinical reasoning, to make a decisive clinical decision, i.e., the rapid referral of the patient to the most appropriate treatment pathway effectively reducing the risk of further complications. Delays in diagnosis, can shift the patient’s prognosis unfavorably or result in unnecessary treatments. Careful screening and diagnosis can also assist in the discovery of unusual and rare presentations, providing knowledge useful in the daily clinical practice of healthcare workers (Bevan, Mohamed, and Moran, 2010; Finucane et al., 2020; Lopez et al., 2023; Maselli et al., 2022, 2023; Pennella et al., 2022). Efficient clinical practice requires, first and foremost, ensuring patient safety through an accurate screening process to determine if their condition falls outside the scope of physiotherapy practice (Ojha, Snyder, and Davenport, 2014). Physiotherapists should always consider non-musculoskeletal diagnoses when working through a differential diagnosis and be prepared to refer for specialty review when indicated (Finucane et al., 2020; Maselli et al., 2016). Therefore, it could be useful to implement procedures from medical semiotics in their physical examination (e.g., McBurney’s test). Combined with careful clinical reasoning, these strategies can lead to a suitable patient referral (Finucane et al., 2020; Maselli et al., 2016; Mourad et al., 2016). This practice should aim not to make a medical diagnosis but to identify signs and symptoms outside of the individual practitioner’s scope of practice (Goodman, Heick, and Lazaro, 2018). While it is crucial to continue to train clinicians in the acquisition of treatment skills (Rossettini et al., 2017) and the prevention of work-related musculoskeletal disorders (Rossettini et al., 2016), differential diagnosis also should be promoted and developed within the core curriculum of physiotherapists (Maselli et al., 2022).

Author contributions

Concept/idea/research design: M. Mannarini, G. Giannotta, M. Cioeta

Writing: M. Mannarini, F. Maselli, G. Giannotta, M. Cioeta, G. Giovannico

Data collection: M. Mannarini

Data analysis: M. Mannarini, F. Maselli, G. Giannotta, M. Cioeta, G. Giovannico

Project management: M. Mannarini, G. Giannotta, M. Cioeta, G. Giovannico

Consultation (including review of manuscript before submitting): M. Mannarini, F. Maselli, G. Giannotta, M. Cioeta, G. Giovannico

Ethics approval

Written informed consent was obtained from the patient for publication of this case report and any accompanying images.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The authors confirm that the data supporting the findings of this study are available within the article.

Additional information

Funding

The research activity of Matteo Cioeta and Gabriele Giannotta was funded by the Italian Ministry of Health (Ricerca Corrente).