The Evaluation and Treatment of Pancoast Tumors

Evaluation and treatment of Pancoast Tumors

Introduction

Several weeks ago a very close friend of mine contacted me with the news he had been diagnosed with lung cancer, with a prediction by his doctor not much could be done. Since we live on opposite sides of the (Atlantic) Ocean, all subsequent discussions were done by phone and without the benefit of interaction with the local physician, actual lab data, X rays, CT scans etc. Despite this, I was able to put together a fairly complete picture of his condition, the stage of disease, as well as treatment plans and prognosis of, as in this case, a particular form of lung cancer: a Pancoast Tumor. Whether or not surgery is possible in his case has a major impact on survival as the discussion below will demonstrate.

Background

Pancoast tumors represent a small percentage of the Lung cancer population (1-5%). They may arise from either left or right upper lobes and tend to invade "the parietal pleura, endothoracic fascia, subclavian vessels, brachial plexus, vertebral bodies, and first upper ribs". Their clinical features are influenced by their location and type of invasion of the thoracic inlet.

Before 1950 it was considered to be inoperable and uniformly fatal. Paulson and Shaw demonstrated in 1961 the possibility of successful resection and improved long term survival considerably by using a combination of radiation and surgical treatment: 5-year survival was 31% and for patients with no nodal involvement 44%. Since then, a combination of evolving surgical techniques and associated chemo-radiation therapy have improved long term survival in some published reports to over 50%, depending of course on how advanced the disease is at the time of first presentation.

Staging

The decision of which patients with a Pancoast tumor should undergo surgery or have a nonsurgical approach of chemo/radiation is often quite varied with cases that don’t fit into any “classic” treatment approach, and there is rarely one best strategy. However, the basis of any treatment involves the obvious observation that a more advanced case has a worse prognosis. To this effect, a cancer staging system has been developed.

Non Small Cell Lung Cancer (NSCLC) staging is a combination of three factors:

1) Tumor (T) stage — from 1 to 4, going from smallest and easiest to remove to hardest or largest to remove

2) Node (N) stage — from 0 to 3, going from none to further distances from the main tumor

3) Metastasis (M) stage — just a 0 or 1, to reflect whether there has been distant spread outside of the tumor’s lobe of origin:

The stage of disease is closely related to long-term survival:

By virtue of their location and chest wall involvement, Pancoast tumors are typically defined as at least T3 lesions. Invasion of the brachial plexus, mediastinum, or spine, elevates their classification to T4. Thus, by definition Pancoast tumors are at minimum stage IIB tumors at the time of presentation.

Treatment

  • Surgery
    • Lobectomy rather than wedge resection has been shown to improve survival.
    • Vascular and vertebral body involvement was once considered a contraindication to surgical intervention. However, as surgical technique and technology have evolved, these tumors may now undergo resection.
    • Extensive involvement of the brachial plexus remains a contraindication to resection; however, Horner’s syndrome is not a contraindication.
    • Metastasis to contralateral mediastinal lymph nodes is considered a contraindication for surgical resection.
  • Radiation therapy
    • External beam or brachytherapy generally used as multimodality therapy prior to surgery, which improves resectability, decreases tumor seeding at surgery, blocks lymphatic channels, and increases local control.
  • Chemotherapy
    • Historically utilized as palliative treatment in metastatic disease.
    • Current treatment now involves chemotherapy as induction therapy prior to definitive surgery or radiation therapy or with concurrent radiation therapy.
    • Concurrent chemotherapy and radiation therapy followed by surgery
    • Combined chemo and radiation prior to surgery has been shown to:
    • Increase the rate of complete resection (92% vs. average 66% with conventional therapy of radiation prior to surgery).
    • Decrease local recurrence rate (23% vs. 58%).
    • Increase 2 yr survival (55% vs. 42%).
    • Over 1/3rd of patients have complete pathologic responses, while an additional 30% have minimal microscopic disease upon resection.

Thus, preoperative chemoradiotherapy has become the standard of care for patients with Pancoast tumors.

What are the possible outcomes?

Various publications showed that

  • Induction Chemo/radiotherapy (CT/RT) can be administered with low morbidity, a higher complete resection rate, a high pathologic response rate, a reduced recurrence rate and improved survival
  • Long-term survival is possible at 5 years after surgery according to stage of disease: ranging from 46% for complete resections to 0% for lesions with advanced disease.

All reports have shown that long-term survival is dependent on a successful operation and removal of the tumor as the backbone of all combined treatments.

Successful surgery is dependent on a number of factors that include:

  1. Location and local invasion and involvement of nearby anatomical structures (also called "Staging")
  2. Completeness of the resection
  3. Condition of the patient.

Location

Pancoast tumors (or Superior sulcus tumors as they are sometimes called) may occur in three locations. Symptoms are related to the location:

  • Anterior, with the risk of invasion and obstruction of the major blood vessels to the arm
  • Middle, in which they may invade the brachial plexus (nerves) to the arm. These patients often present with pain that begins in the shoulder and then extends down to the back of the arm onto the small and ring fingers. This pain can be very intensive and often patients are first submitted to other therapists. With increasing pressure on the nerve roots, muscle atrophy of the hand and loss of the triceps reflex can occur. Because of these aspecific complaints, the time between onset of symptoms and diagnosis may take as long as 6 – 10 months.
  • Posterior, with risk of growth into the stellate ganglion or vertebral bodies of the cervical spine. Tumor invasion of the sympathetic nerves may cause the so-called Horner’s syndrome (ipsilateral ptosis, miosis, and anhydrosis):

Complete resection

A complete resection means successful removal of the entire tumor and that portion of the involved lung and may include the involved anatomical structures, resulting sometimes in different approaches (from the front or back), therefore demanding considerable skill and anatomical knowledge of the surgeon involved. However, in skilled hands, the results speak for themselves, with long-term survival results ranging from 56 to 84%:

Preoperative chemoradiotherapy followed by surgical resection for patients with superior sulcus tumours

Author No. of patients Complete resection (%) 4-year survival (%)
Martinez-Monge (1994) 18 76 56

Rusch (2001)

111 92 55, patients with CR 70 (2-year)
Wright (2002) 15 92 84
CR, complete resection.

Shahian and colleagues reported on 18 patients who were treated with preoperative radiotherapy. Fourteen of these patients also received postoperative radiotherapy because of N2 disease, positive resection margins, or both. Overall 5-year survival was 56%. As this series was reported by the service I was involved with as a resident in Thoracic Surgery, I participated a number of operations involving these patients, which shaped my practice later on in my career!

Despite these favorable reports, a high incidence of local recurrence is reported even in patients with so-called complete resections. Even in these patients, 66% of the cases had a local recurrence in a study by Ginsburg with most frequent sites of recurrence the spine, chest wall and lung.

However, treatment with combined preoperative chemo/radiation seems to lower this incidence of local recurrence to 23% (Rusch and associates).

Condition of the patient

No surgery can be completed successfully unless the patient is strong enough to undergo the procedure, especially one that is potentially as complicated as an operation for a Pancoast lung tumor. Therefore lung function needs to be adequate to loose potentially 30-50% of the involved lung, and the other major organs such as heart and general condition of the patient play an equally important factor in the decision making process.

“My Patient”

Since my friend is neither my patient, nor do I have direct access to the necessary data, there was a certain amount of guesswork involved in assessing his case. However, I believe I was able to reconstruct a fairly complete picture of his situation and help him with a treatment plan that I would like to share here.

This then is a discussion of his situation and my subsequent recommendations:

Present symptoms

None, other than some local numbness in his right axilla.  This tumor was found on a routine chest X ray. Describing his X ray to me, I diagnosed a Pancoast tumor, later confirmed by his doctor. A similar picture would look like this:

The CT scan did show only local disease, but a PET Scan later suggested potential node involvement adjacent to the bifurcation (split) between left and right major bronchi (the windpipes to both lungs).

Stage of disease

As only clinical staging is available at this point, and no direct invasion of major organ systems demonstrated with unknown lymph nodal disease, this lung cancer should be staged as a Stage IIB (T3N0M0) cancer. If this node proves positive, the stage would be adjusted to Stage IIIA (T3N1 or 2M0).

Overall Health

"My patient" is in excellent health with an equally excellent performance status and had recently returned from a ski vacation – he is an aggressive skier and goes “all-out” despite the fact that he is now in his early seventies.

Anatomic considerations

Where is the tumor and does it involve any structures outside the lung?

  • From the description he gave me, I learned the following: it is probably a fairly early tumor that has yet to invade a major organ system, with exception of the potentially positive node seen on PET Scan.
  • The area of the location of the tumor inside the chest is represented by the oval:

  • Other anatomic features to be considered are depicted in the following figures:

I deducted also the following, this tumor does not invade structures medially (the “Mediastinum”), nor major nerves or vascular structures, but from the axillary numbness I assume involvement of the T1-3 Dermatomes, well below the Brachial Plexus (the nerves to “my patients” right arm:



The brachial Plexus is not involved (yet), but a careful review of the CT Scans/MRA of the chest should elucidate that issue:

A resection of the first rib requires careful protection of the C8-T1 Rami & Trunks.

Therefore a resection would probably involve removal of that portion of the chest wall, including the 1st through 3rd ribs, easily tolerated and without major long-term adverse functional consequences.

There are a number of surgical options to approach this resection that are dependent on the location and may include

a)    A traditional posterior approach, as suggested by Paulson:

b)   An anterior “trap-door” exposure, usually requiring a 2nd incision to complete the lobectomy as popularized by Dartevelle and Grunenwald:

c)    Potentially possible in this case, an axillary approach, as used occasionally for treatment of Thoracic Outlet Syndrome, also requiring a second incision:

Risk Factors

Risk factors included heavy smoking, a very successful Coronary Artery Bypass operation (also on a previous recommendation from me), hypertension and a high cholesterol, all under medical control.

Since formal consultation that included an examination and review of all available medical data, my limited assessment therefore was still that he would easily tolerate a major operation and the loss of 30% (in his case) of his lung.

As a result, I strongly recommended that my friend follow my suggestions and find a surgeon, experienced in this type of surgery. My recommendations also included to consider an operation first, followed by chemo/radiation therapy, as opposed to preop CT/RT.

The question of a biopsy of the potential positive node should be addressed at the time of surgery,as preoperative assessment of this node and in this case, should be limited to patients with a poor performance status, who might not tolerate such a big operation.

The anticipated benefits should include:

  • Smooth recovery
  • Adequate Pulmonary reserve
  • An excellent postoperative functional result
  • A better than 50% long-term survival chance.

I hope this example of the application of the surgical and medical literature to a specific patient situation is of interest,

Dr T
http://www.cardiachealth.org/

References:

1: Shaw RR, Paulson DL, Kee JL. Treatment of the superior sulcus tumour by irradiation followed by resection. Ann Surg 1961;154: 29–40.

2: Dartevelle PG, Chapelier AR, Macchiarini P, Lenot B, Cerrina J, Ladurie FL, Parquin FJ, Lafont D: Anterior transcervical-thoracic approach for radical resection of lung tumors invading the thoracic inlet. J Thorac Cardiovasc Surg 1993, 105(6):1025-34.

3: Ginsberg RJ, Martini N, Zaman M, Armstrong JG, Bains MS, Burt ME, McCormack PM, Rusch VW, Harrison LB. Influence of surgical resection and brachytherapy in the management of superior sulcus tumour. Ann Thorac Surg 1994;57:1440–5

4: Grunenwald D, Spaggiari L: Transmanubrial osteomuscular sparing approach for apical chest tumors. Ann Thorac Surg 1997, 63:563-66.

5: Shahian DM, Neptune WB, Ellis FH. Pancoast tumours: improved survival with pre-operative and postoperative radiotherapy. Ann Thorac Surg 1987;43:32 – 8.

6: Martinez-Monge R, Herreros J, Aristu JJ, Aramendia JM, Azinovic I. Combined treatment in superior sulcus tumours. Am J Clin Oncol 1994;17:317 – 22.

7: Rusch VW, Giroux DJ, Kraut MJ, Crowley J, Hazuka M, Johnson D, Goldberg M, Detterbeck F, Shepherd F, Burkes R, Winton T, Deschamps C, Livingston R, Gandara D. Induction chemoradiation and surgical resection for non-small cell lung carcinomas of the superior sulcus: initial results of the Southwest oncology group trial 9416 (intergroup trial 0160). J Thorac Cardiovasc Surg 2001;121: 472 – 83.

8: Wright CD, Menard MT, Wain JC, Donahue DM, Grillo HC, Lynch TJ, Choi NC, Mathisen DJ. Induction chemoradiation compared with induction radiation for lung cancer involving the superior sulcus. Ann Thorac Surg 2002;73:1541 – 4.

9: C.C.M. Pitz et al. / European Journal of Cardio-thoracic Surgery 26 (2004) 202–208

10: Parissis and Young Journal of Cardiothoracic Surgery 2010, 5:102

11: L. Spaggiari et al. / Multimedia Manual of Cardiothoracic Surgery / doi:10.1510/mmcts.2005.001776

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