Chronic Pain in the Lower Rib Cage – Suspected Intercostal Neurinoma
67-year-old male began to complain of chronic pain in the left lower rib cage. The pain is stitch, ever-present, dull and localized at the level of his left last rib, and became slightly worse in the last 2 years. Recent image findings: MRI - "Ovalish hypoechogenic solid formation, Ultra sound - "Suspected intercostal neurinoma at ribs 10, 11 and 12. The expert agrees with the diagnosis of intercostal neuroma in the region of the left lower rib cage, and recommends starting with diagnostic blocks followed by trying RF or cryo intercostal blocks as a long lasting therapeutic approach.
1. What could be the cause of the patient’s pain?
2. Are there any other tests he could carry out?
3. Is there a specific centre that the patient could contact?
4. What therapy could he try?
5. What therapy would you advise? Do you deem surgical excision of the neurinoma necessary as suggested by the pain therapy specialist consulted at Istituto Maugeri in Pavia?
6. If you agree with the surgical intervention, do you also share the belief that this procedure should be performed by a thoracic surgeon or is a different specialist surgeon preferable?
7. How would you rate a completely successful outcome of surgery? What percentage and what kind of negative outcome could you envision?
Diagnosis: chronic pain to be further determined
Case history and clinical report: 67 years-old male patient, in reasonably good health conditions. Ex-smoker (2002) of 20 cigarettes a day. In 2002 finding of dilated cardiomyopathy which was treated with Cardioaspirin and two drugs not better specified. In 2006, in consequence of abdominal pain, he carried out a Colonscopy that showed a mild, non-complicated, diffuse diverticulitis and the presence of two polyps that were removed during the examination; the first one at the level of the descending colon (histology: villoglandular adenoma with low grade dysplasia) and the second one at the rectal level (histology: hyperplastic polyp with eroded surface).
The reason for requesting a second opinion dates from 2005; the patient begins to complain of a stitch pain, fixed, localized at the level of his left last rib. Such pain does not change when breathing, but it sometimes changes with the posture and gets slightly worse after meals. It is an ever-present dull pain, but not so crippling. The patient begins to carry out a set of examinations.
July, 2006: Chest and Hemithorax X-ray: No current focal pleural lesions. Slight reinforcement of bronchovascular markings in the inferior hilar-perihilar region due to known bronchial problems. Mediastinum in situ and not enlarged. Medium volume hila. Heart within normal limits. Initial lengthening and opacification of the aortic arch. No evident current structural bone lesion foci or trauma of costal skeletal segments in left hemithorax under examination. In some X-rays there is a small round opaque area with distinct edges in the medial anterior arch of the sixth rib, possible indication of an area of compact bone or possibly an osteoma. However, also according to the clinical findings it requests a further radiological follow-up in the near future and, subject to clinical opinion, a possible diagnostic deepening by means of a scintigraphy.
Total body bone scintigraphy: “no increase in the osteoblast turnover involving the medial anterior length of the left sixth rib, which was the location of a round opaque area in an X-ray carried out on 07. 06.”
The X-ray carried out in January, 2007 does not show significant changes compared to previous picture.
February,2007: The results of the muscle and tendon echo–tomography of the left hemithorax are within normal limits. He also undergoes neurological examination given the suspicion that this pain might be of neuropathic origin but the neurologist, based on the objective examination, tends to exclude this possibility although he prescribes a therapy with Pregabalin (75 mg X2, which was never taken), a dorsal and thoracic MRI of the lower thorax and last vertebrae (D5-D12), anti-HSV and anti-HZV antibody dose.
Antivaricella IgG antibodies in serum 911.30MlU/ml (>195=positive); Antivaricella IgM antibodies in serum <0.9 (negative).
March, 2007 Chest MRI + Dorsal Spine MRI: No significant asymmetries of the rib cage. No observed expansions abnormalities of the left hemithorax in the painful area reported by the patient. No muscle abnormalities. Metamers in the dorsal spine region are correctly aligned in the sagittal plane and there are no bone lesions of current pathological significance. Presence of diffuse arthritic abnormalities that are more significant in the inferior dorsal side with marginal somatic border osteophytosis. At the discs level there are mild degenerative abnormalities mainly characterized by dehydration of the pulpy nuclei. No images to be related to herniated discs nor to significant protrusions. The intrinsic signal of the spinal marrow is maintained in both captures.
Chest CAT scan: The assessment of the mediastinum shows the presence of aortic and coronary calcifications as well as small reactive limph nodes in the paratracheal region. Gall bladder calculus is observed. The pulmonary parenchyma is preserved. No pleural or pericardial effusion. The skeletal assessment shows that calcium content has been maintained and diffuse medio-dorsal spondylosis features. Presence of diffuse chondral calcifications. A small sclerotic area is observed in the medial arch of the sixth rib. In addition, dysmorphism is observed in the third anterior rib and costochondral joint of the ninth rib likely due to the stabilized trauma results. At last, a slight linear calcification is observed in the soft tissues of the anterior muscle wall at the apex of the eleventh rib.
Anti-HSV1 antibodies present in serum (IGG); absence of HSV2; HZV (IGG) present.
In July, 2007 tests for faecal occult blood were positive in 2 out of 3 samples.
In the last two years the pain has become slightly worse. The patient has never taken pain medications and he can sleep at night.
Recent image findings
1. MRI (6. 2009) a finding of- "Ovalish hypoechogenic solid formation measuring 12x19mm in the left hemithorax."
2. Ultra sound performed over the painful area - "Suspected intercostal neurinoma at ribs 10, 11 and 12.
Chief complaint: Chronic pain in the left lower rib cage.
Both of the recent findings suggest the diagnosis of intercostal neuroma in the region of the left lower rib cage as a most reasonable diagnosis.
Following this working diagnosis I was asked to respond to several questions.
1. What therapy would you advise? Do you deem surgical excision of the neurinoma necessary as suggested by the pain therapy specialist consulted at Istituto Maugeri in Pavia?
Reply: The recent imaging findings have to be observed in light of the pain complaints. If the imaging findings were not followed by pain the question of the need for surgical resection should be discussed in a different manner and needle biopsy or observation followed by a repeat image study after some time would be reasonable approaches.
Intercostal neuralgia is typically followed by superficial sensory changes such as hypo or hyperalgesia and alodinia to light touch that were not reported in this case. The absence of these clinical findings does not exclude the diagnosis. I would recommend considering diagnostic intercostal blocks at the appropriate levels to confirm diagnosis. If intercostals blocks result in temporary analgesia a radio-frequency (R.F) or cryoanalgesia long lasting block may be considered as a long lasting therapeutic approach. If these more conservative forms of treatment do not give satisfactory analgesia I would consider surgical resection as the next stage.
Other more conservative forms of analgesic treatment could also be considered, such as local anaesthetic patches (Lidoderm or Synera) or systemic medications for neuropathic pain.
2. If you agree with the surgical intervention, do you also share the belief that this procedure should be performed by a thoracic surgeon or is a different specialist surgeon preferable?
Reply: The surgical resection should preferably be done by a minimally invasive endoscopic approach as opposed to an open thoracothomy. This will reduce soft tissue injury and will shorten recovery. Therefore, a thoracic surgeon experienced with this approach would be preferred. I would also recommend having a surgeon experienced with resection of neuromas involved in the surgery.
3. How would you rate a completely successful outcome of surgery? What percentage and what kind of negative outcome could you envision?
Reply: There is an ongoing debate as to the need for surgical resection of painful peripheral neuroma. The reason for the debate is that in some cases the resection will not improve the pain and more so, in some cases pain may be exacerbated following the procedure.
Due to the lack of randomised controlled studies comparing the different approaches it is impossible to give an accurate estimate of success.
In conclusion I would recommend starting with diagnostic blocks followed by trying RF or cryo intercostal blocks. If the diagnostic blocks suggest that the pain is of intercostal neural origin yet the pain is not adequately treated in the long term by these procedures, then I would consider neurectomy as the next step.
Suggested Reading: A recent relevant publication.
Neurectomy for treatment of intercostal neuralgia.
Williams EH, Williams CG, Rosson GD, Heitmiller RF, Dellon AL.
Ann Thorac Surg. 2008 May;85(5):1766-70.